Filed by Vertex Pharmaceuticals Incorporated
                       Pursuant to Rule 425 under the Securities Act of 1933
                       Subject Company:  Aurora Biosciences Corporation
                       Commission File Number:  000-22669

The following communications contain forward-looking statements within the
meaning of the Safe Harbor Provisions of the Private Securities Litigation
Reform Act of 1995 about Vertex Pharmaceuticals Incorporated, Aurora
Biosciences Corporation, and the proposed merger. While management of Aurora
and Vertex make their best efforts to be accurate in making forward-looking
statements, any such statements are subject to risks and uncertainties that
could cause actual results to vary materially. The forward-looking statements
herein address the following subjects: the expected benefits that could be
realized by the combined company, including the combined company's ability to
(i) significantly enhance Vertex's drug discovery, technology and research
capabilities, and the development of Vertex's product pipeline and ability to
apply these enhancements to additional gene families, (ii) create a
comprehensive, scalable platform for systematically accelerating drug
candidate output in target-rich gene families, (iii) accelerate the creation
of a broad intellectual property estate, (iv) accelerate target selection,
lead generation, lead optimization, drug candidate selection, and the
establishment of clinical proof-of-concept data and the therapeutic profile
of development stage drug candidates using Aurora's technologies and
personnel, (v) extend Vertex's position in gene family-based drug discovery,
(vi) continue to derive revenues from existing and new corporate
collaborations, (vii) immediately and systematically boost research output in
multiple gene families, creating near and long-term value for shareholders,
(viii) maintain existing, and develop new, strategic collaborations, (ix)
realize enhanced product, business development and commercial opportunities,
(x) create the premier fully-integrated next generation pharmaceutical
company, (xi) approximately double Vertex's annual revenues, (xii) add
additional value-added products and services to Aurora's products and
services through Vertex's technologies and provide more R&D support to
Aurora's relationships, and (xiii) have cell-based assays that target more
than 350 targets in 2001.

Additional forward-looking statements relate to the expected closing date of
the merger, value of the Vertex consideration and the aggregate number of
Vertex shares that the Aurora stockholders will receive on the closing date,
the effect the transaction, excluding merger-related expenses, is expected to
have on Vertex's previously announced net operating results projections for
2001, and the expectation that Aurora's first-quarter financial results will
be consistent with previous guidance, the expectation that Aurora will
continue to conduct its business as planned once the merger is completed,
including expanding Aurora's UHTSS system business, the anticipation that
Aurora's customers will view the merger as positive in that the combined
company will be able to continue its commitments to existing contracts, and,
perhaps extend the relationships further, the expectation of recording one
time charges associated with the transaction in 2001, which should be in
excess of $10 million, the belief that the merger achieves an excellent
strategic fit with Vertex that will fully capture the potential of Vertex's
technology platform and tap the product creation potential of the human
genome, the aggregate revenue projections for the two companies, and Aurora's
and Vertex's commitment to achieving their existing milestones for 2001.
Vertex and Aurora disclaim any intention or obligation to update or revise
any forward-looking statements, whether as a result of new information,
future events or otherwise.

The following factors, among others, could cause actual results to differ
materially from those described in the forward-looking statements: costs related
to the merger, failure of Vertex's or Aurora's stockholders to approve the
merger, Vertex's or Aurora's inability to satisfy the conditions of the merger,
the risk that Vertex's and Aurora's businesses will not be integrated
successfully, the termination of existing Aurora pharmaceutical and
biotechnology collaborations, the combined company's inability to further
identify, develop and achieve commercial success for new products and
technologies, the possibility of delays in the research and development
necessary to select drug development candidates and delays in clinical trials,
the risk that clinical trials may not result in marketable products, the risk
that the combined company may be unable to successfully finance and secure
regulatory approval of and market its drug candidates, risks associated with
Aurora's new and uncertain technology, dependence upon pharmaceutical and
biotechnology collaborations, the development of competing systems, the combined
company's ability to protect its proprietary technologies, patent-infringement
claims, risks of new, changing and competitive technologies and regulations in
the U.S. and internationally.



THE FOLLOWING IS THE PRESS RELEASE DISSEMINATED BY VERTEX AND AURORA ON APRIL
30, 2001 AND FILED ON APRIL 30, 2001 ON A FORM 8-K WITH THE SEC.



FOR IMMEDIATE RELEASE

              VERTEX PHARMACEUTICALS TO ACQUIRE AURORA BIOSCIENCES
  -- VERTEX TO INTEGRATE AURORA'S CORE STRENGTHS IN CELL ASSAY DEVELOPMENT AND
ULTRA HIGH THROUGHPUT SCREENING TO ACCELERATE DRUG DISCOVERY IN GENE FAMILIES --

APRIL 30, 2001, SAN DIEGO, CA AND CAMBRIDGE, MA -- Vertex Pharmaceuticals
Incorporated (Nasdaq:VRTX) and Aurora Biosciences Corporation (Nasdaq: ABSC)
announced today that they have signed a definitive agreement whereby Vertex will
acquire Aurora in a stock-for-stock transaction. The fully-diluted equity value
of the transaction is approximately $592 million. The agreement will unite
Aurora's industry-leading assay development, screening and cell biology
capabilities with Vertex's integrated drug discovery expertise, creating a
comprehensive, scalable platform for systematically accelerating drug candidate
output in target-rich gene families. The combination of Vertex's and Aurora's
technology and expertise is expected to:

     o    increase the flow of novel drug candidates into development,

     o    accelerate the creation of a broad intellectual property estate, and

     o    provide enhanced opportunities for major drug discovery, development
          and commercial alliances.

Under the terms of the agreement, which have been approved by the Boards of
Directors of both Vertex and Aurora, each share of Aurora will convert into
shares of newly issued Vertex common stock at a fixed ratio of 0.62 shares of
Vertex common stock for each share of Aurora common stock. Based on the closing
price of Vertex stock of $39.25 on April 27, 2001, the fixed exchange ratio
implies a price of $24.34 per Aurora share, a 44 percent premium to the closing
price of $16.85 on April 27, 2001. Vertex will be obligated to issue a total of
approximately 14.0 million shares of common stock in exchange for Aurora's
outstanding common stock, and Aurora options will be equitably converted to
Vertex options. The transaction will be structured as a tax-free share exchange
and is intended to be accounted for as a pooling-of-interests. Directors and
officers of both companies have agreed to vote their shares in favor of the
merger. The merger is subject to approval by both Vertex's and Aurora's
shareholders, regulatory approval and other closing conditions, and is expected
to close in the third quarter of 2001. The transaction, excluding merger-related
expenses, is not expected to materially affect Vertex's previously announced net
operating results projections for 2001. As of December 31, 2000, Aurora had
approximately $100 million in net cash.


                                   -- more --


Page 2


After the merger, Aurora will operate as a wholly-owned subsidiary of Vertex
Pharmaceuticals and will continue to carry the Aurora name. Aurora will continue
to pursue its strategy of collaborating with new and existing partners in all
capacities. Harry Stylli, Ph.D., Aurora's Senior Vice President of Commercial
Development, will be president of the Aurora subsidiary.

"Aurora has developed a compelling suite of technologies that has the potential
to accelerate target selection, lead generation and optimization, drug candidate
selection and establishment of clinical proof-of-concept across multiple gene
families," said Joshua Boger, Ph.D., Vertex's Chairman and CEO. "By integrating
Aurora's capabilities within Vertex's chemogenomics platform, we believe we will
be able to rapidly expand research into major new gene families, as well as
enhance our existing multi-target research programs in the kinase and caspase
gene families. In addition, we believe that Aurora's proteomics and assay
development expertise are broadly applicable in our clinical programs, and will
enable us to more rapidly establish the therapeutic profile of our
development-stage drug candidates."

"This merger fulfills a near term goal that we have emphasized over the past six
months in our public communications and guidance to the financial community,
which is to extend our leadership position in gene family-based drug discovery
through internal expansion and complementary acquisitions," added Dr. Boger.

"Our core strengths in assay development and ultra high throughput screening are
an excellent strategic fit with Vertex's chemogenomics platform," said Stuart
J.M. Collinson, Ph.D., Aurora's Chairman, CEO and President, who will join
Vertex's Board of Directors when the merger closes. "The agreement with Vertex
significantly accelerates our comprehensive drug discovery initiatives and
creates new and enhanced partnership opportunities in the years ahead. Together
with Vertex, we believe that we can immediately and systematically boost our
collective research output in multiple gene families, creating near and
long-term value for shareholders."

VERTEX AND AURORA:  DRUG DISCOVERY ADVANTAGES IN MULTIPLE MAJOR GENE FAMILIES
The combined company will have one drug on the market, the HIV protease
inhibitor Agenerase(R), and 12 drug candidates in clinical development targeting
the treatment of viral diseases, cancer, autoimmune and inflammatory diseases,
and neurological diseases. The combined company's integrated technology platform
will be supported by more than 25 collaborative and licensing agreements with
research institutions and major pharmaceutical companies, including American
Home Products, Aventis, Bristol-Myers Squibb, GlaxoSmithKline, Eli Lilly,
Johnson & Johnson, Merck, Novartis, Pfizer, Pharmacia and Roche.


                                   -- more --


Page 3


Vertex has extensive efforts underway to discover and develop small molecule
inhibitors for specific targets in the kinase and caspase gene families, and the
merger is expected to significantly enhance Vertex's drug discovery capabilities
in these and other major gene families and target classes. The merger enables
Vertex to integrate Aurora's industry-leading capabilities in the development of
cell-based assays and screening instrumentation for use in drug discovery
directed at ion channels, g-protein coupled receptors (GPCRs), kinases,
proteases and phosphatases, and for use in target validation in a wide range of
gene families. Vertex's ongoing drug discovery efforts will also benefit from
Aurora's predictive pharmacology and proteomics technologies, which use
high-throughput assessments of toxicology and metabolic markers to establish
therapeutic proof-of-concept and safety of drug candidates in early clinical
testing. Aurora's recent acquisition of PanVera, a specialty supplier of high
quality recombinant proteins, provides a further, valuable asset in drug
discovery.

Based on the companies' combined drug discovery advantages in gene families,
Vertex and Aurora foresee enhanced business development and commercial
opportunities. This expectation is based on enhanced productivity in discovery
and development, leading to an increased output in proprietary new small
molecule drug candidates. Existing and new corporate collaborations will
continue to be important sources of revenue for the combined company.

First-quarter financial results for Aurora are expected to be consistent with
previous guidance. Further information regarding Aurora's first-quarter results
will be disclosed on May 3, 2001.

Vertex was advised by Merrill Lynch and Aurora was advised by Goldman Sachs.

ABOUT AURORA
Aurora Biosciences(R) is a drug discovery company that uses proprietary advances
in biology, chemistry and automation to accelerate the discovery of new
medicines. Aurora's core technologies include a broad portfolio of proprietary
fluorescence assay technologies and screening platforms designed to provide an
integrated solution for drug discovery. Aurora's fluorescence assay technologies
include GeneBLAzer-TM-, GenomeScreen-TM-, PhosphoryLIGHT-TM- and Vivid-TM-
technologies, as well as a broad collection of fluorescent proteins.

                                   -- more --


Page 4


Aurora's screening platforms include an ultra high throughput screening system,
the UHTSS(R) Platform, Aurora's automated master compound store, the AMCS, and
an ion channel technology screening platform, which includes Aurora's
proprietary voltage sensor probes and a voltage ion probe reader, the VIPR-TM-
subsystem. Aurora also provides assay development and screening services as part
of its drug discovery collaborations. Aurora's Big Biology-TM- initiative is an
internal drug discovery program focused on the identification of promising
preclinical candidates within all major classes of gene targets. Aurora's
technologies and drug discovery capabilities have been commercially validated by
over 20 major life sciences companies and research organizations, including
American Home Products, Bristol-Myers Squibb, Ceres, Cystic Fibrosis Foundation,
Eli Lilly, Families of SMA, GlaxoSmithKline, Genentech, Johnson & Johnson,
Merck, NV Organon Laboratories, Pfizer, Pharmacia and Roche.

ABOUT VERTEX
Vertex Pharmaceuticals Incorporated is a global biotechnology company. Vertex
seeks to discover, develop, and commercialize major pharmaceutical products
independently and with partners. Chemogenomics, Vertex's proprietary,
systematic, genomics-based platform, is designed to accelerate the discovery of
new drugs and to expand intellectual property coverage of drug candidate
compounds and classes of related compounds. This approach, which targets gene
families, has formed the basis for several commercial collaborations that retain
rights to downstream revenue for Vertex. Vertex's first approved product is
Agenerase(R) (amprenavir), an HIV protease inhibitor, which Vertex co-promotes
with GlaxoSmithKline. Vertex has 12 drug candidates in development to treat
viral diseases, inflammation, cancer, autoimmune diseases and neurological
disorders.

Safe Harbor Statement
This press release contains forward-looking statements about Vertex, Aurora, and
the proposed merger. While management of Aurora and Vertex make their best
efforts to be accurate in making forward-looking statements, any such statements
are subject to risks and uncertainties that could cause actual results to vary
materially. The forward-looking statements in this release address the following
subjects: the expected benefits that could be realized by the combined company,
including the combined company's ability to (i) significantly enhance Vertex's
drug discovery and research capabilities, (ii) create a comprehensive, scalable
platform for systematically accelerating drug candidate output in target-rich
gene families, (iii) accelerate the creation of a broad intellectual property
estate, (iv) accelerate target selection, lead generation, lead optimization,
and drug candidate selection using Aurora's technologies, (v) extend Vertex's
position in gene family-based drug discovery, (vi) continue to derive revenues
from existing and new corporate collaborations, (vii) immediately and
systematically boost research output in multiple gene families, creating near
and long-term value for shareholders, (viii) maintain existing, and develop new,
strategic collaborations, and (ix) realize enhanced business development and
commercial opportunities.


                                   -- more --


Page 5


Additional forward-looking statements relate to the expected closing date of the
merger, value of the Vertex consideration that the Aurora stockholders will
receive on the closing date, the effect the transaction, excluding
merger-related expenses, is expected to have on Vertex's previously announced
net operating results projections for 2001, and the expectation that Aurora's
first-quarter financial results will be consistent with previous guidance.
Vertex disclaims any intention or obligation to update or revise any
forward-looking statements, whether as a result of new information, future
events or otherwise.

The following factors, among others, could cause actual results to differ
materially from those described in the forward-looking statements: costs related
to the merger, failure of Vertex's or Aurora's stockholders to approve the
merger, Vertex's or Aurora's inability to satisfy the conditions of the merger,
the risk that Vertex's and Aurora's businesses will not be integrated
successfully, the termination of existing Aurora pharmaceutical and
biotechnology collaborations, the combined company's inability to further
identify, develop and achieve commercial success for new products and
technologies, the possibility of delays in the research and development
necessary to select drug development candidates and delays in clinical trials,
the risk that clinical trials may not result in marketable products, the risk
that the combined company may be unable to successfully finance and secure
regulatory approval of and market its drug candidates, risks associated with
Aurora's new and uncertain technology, dependence upon pharmaceutical and
biotechnology collaborations, the development of competing systems, the combined
company's ability to protect its proprietary technologies, patent-infringement
claims, risks of new, changing and competitive technologies and regulations in
the U.S. and internationally.

Investors and security holders are advised to read the joint proxy
statement/prospectus regarding the proposed merger when it becomes available,
because it will contain important information. Such joint proxy
statement/prospectus will be filed with the Securities and Exchange Commission
by Vertex and Aurora. Investors and security holders may obtain a free copy of
the joint proxy statement/prospectus (when available) and other documents filed
by Vertex and Aurora at the Securities and Exchange Commission's web site at
www.sec.gov. The joint proxy statement/prospectus and such other documents may
also be obtained from Vertex by directing such request to Vertex
Pharmaceuticals, 130 Waverly Street, Cambridge, MA 02139, Attn: Investor
Relations, tel: (617) 577-6000; e-mail: InvestorInfo@vpharm.com. The joint proxy
statement/prospectus and such other documents may also be obtained from Aurora
by directing such request to Aurora Biosciences, 11010 Torreyana Road, San
Diego, CA 92121, Attn: Investor Relations, tel: 858-404-6600; e-mail:
ir@aurorabio.com.

Aurora and its executive officers and directors may be deemed to be participants
in the solicitation of proxies from stockholders of Aurora with respect to the
transactions contemplated by the merger agreement. Information regarding such
officers and directors is included in Aurora's Proxy Statement for its 2001
Annual Meeting of Stockholders filed with the Securities and Exchange Commission
on April 18, 2001. This document is available free of charge at the Securities
and Exchange Commission's web site at http://www.sec.gov and from Aurora and
Vertex.


                                   -- more --


Page 6


Agenerase(R) is a trademark of the GlaxoSmithKline group of companies.
Aurora Biosciences(R), Big Biology-TM-, GeneBLAzer-TM- GenomeScreen-TM-
PhosphoryLIGHT-TM- UHTSS-TM-, VIPR-TM- and Vivid-TM- are trademarks of Aurora
Biosciences Corporation.

Vertex's press releases are available at www.vrtx.com, or by fax-on-demand at
(800) 758-5804-- Code: 938395.

CONFERENCE CALL AND WEBCAST
Vertex and Aurora will host a conference call on April 30, 2001 at 9:00 a.m. ET
to review the merits of the transaction. The call-in numbers are as follows:
U.S./Canada: 800-374-0296; International: 706-634-2394. A replay of the call
will be available at 11:00 a.m. ET. The call-in numbers for the replay are as
follows: U.S./Canada: 800-642-1687; International: 706-645-9291. The replay
conference ID is 958173. The conference call will also be broadcast via the
Internet at www.vrtx.com in the investor center.

VERTEX CONTACTS:
Lynne H. Brum, Vice President, Corporate Communications and Market Development,
(617) 577-6614, or
Michael Partridge, Associate Director, Corporate Communications, (617) 577-6108,
or Katie Burns, Manager, Investor Relations, (617) 577-6656, or Renee Connolly,
Assistant Vice President, Noonan/Russo Communications, (212) 696-4455 ext. 227

AURORA CONTACT:
Doug Farrell, Senior Director, Investor Relations and Corporate Communications
Telephone:  (858) 404-6767
Fax:  (858) 404-6714
Email:  ir@aurorabio.com


                                      # # #



                           **************************

Investors and security holders are advised to read the joint proxy
statement/prospectus regarding the proposed merger when it becomes available,
because it will contain important information. Such joint proxy
statement/prospectus will be filed with the Securities and Exchange Commission
by Vertex and Aurora. Investors and security holders may obtain a free copy of
the joint proxy statement/prospectus (when available) and other documents filed
by Vertex and Aurora at the Securities and Exchange Commission's web site at
www.sec.gov. The joint proxy statement/prospectus and such other documents may
also be obtained from Vertex by directing such request to Vertex
Pharmaceuticals, 130 Waverly Street, Cambridge, MA 02139, Attn: Investor
Relations, tel: (617) 577-6000; e-mail: InvestorInfo@vpharm.com. The joint proxy
statement/prospectus and such other documents may also be obtained from Aurora
by directing such request to Aurora Biosciences, 11010 Torreyana Road, San
Diego, CA 92121, Attn: Investor Relations, tel: 858-404-6600; e-mail:
ir@aurorabio.com.

                           **************************

THE FOLLOWING IS THE SCRIPT OF A TELEPHONE CONFERENCE WITH ANALYSTS AND OTHERS
HELD ON APRIL 30, 2001.



               SCRIPT FOR VERTEX/AURORA BIOSCIENCESCONFERENCE CALL



                             MONDAY, APRIL 30, 2001
                             9:00 A.M. EASTERN TIME


                 LYNNE BRUM, STUART COLLINSON, AND JOSHUA BOGER


INTRODUCTION - OPERATOR

GOOD AFTERNOON! MY NAME IS __________ AND I WILL BE YOUR CONFERENCE FACILITATOR
TODAY. AT THIS TIME I WOULD LIKE TO WELCOME EVERYONE TO THE VERTEX
PHARMACEUTICALS AND AURORA BIOSCIENCES' CONFERENCE CALL. ALL LINES HAVE BEEN
PLACED ON MUTE TO PREVENT ANY BACKGROUND NOISE. AFTER VERTEX'S (LEADERS NAME)
REMARKS, THERE WILL BE A QUESTION AND ANSWER PERIOD. IF YOU WOULD LIKE TO ASK
QUESTIONS DURING THAT TIME, PRESS NUMBER ONE ON YOUR KEYPAD. QUESTIONS WILL BE
TAKEN IN THE ORDER THAT THEY ARE RECEIVED. IF YOU WOULD LIKE TO WITHDRAW YOUR
QUESTION, PRESS THE POUND KEY.

LYNNE (LEADER'S NAME), ARE YOU READY TO BEGIN? THANK YOU! YOU MAY NOW
BEGIN YOUR CONFERENCE.


Page 1


VERTEX/AURORA BIOSCIENCES CONFERENCE CALL - LYNNE BRUM

o    Thank you everyone for joining us today. This is Lynne Brum, Vice
     President, Corporate Communications and Market Development, of Vertex.
     Joining me on the conference call today are:
     --   Dr. Stuart Collinson, Chairman, President and CEO of Aurora
          Biosciences (Good morning)
     --   and Dr. Joshua Boger, Chairman and CEO of Vertex Pharmaceuticals (Good
          morning)

o    As we get started, I must remind you that information discussed on this
     conference call may consist of forward looking statements, and as such, are
     subject to the risks and uncertainties discussed in detail in the reports
     filed by Vertex and Aurora with the Securities and Exchange Commission.

o    At this time, the announcement regarding Vertex Pharmaceuticals'
     acquisition of Aurora has been faxed out and e-mailed. In addition, the
     release is posted on both companies' web sites and on various places on the
     Web including Yahoo and PR Newswire.

OVERVIEW OF CALL


Page 2


o    You also can listen to the conference call and view a powerpoint
     presentation on the Vertex web site at www.vrtx.com or on the Aurora site
     at www.aurorabio.com. Once on the Vertex site, select Investor Center, then
     Conference Calls. In addition, a replay of the conference call will be
     available via telephone for three days and via the Internet for
     approximately two weeks.

o    I will begin today's conference call by reviewing the terms of the deal as
     well as the impact of the transaction on our financial guidance going
     forward. I will then review the key drivers of this transaction, from the
     perspective of Vertex drug discovery and development goals in gene
     families. I will also briefly review Vertex's approach to evaluating
     technology licensing and merger and acquisition opportunities, and the
     strategic fit between Aurora and Vertex.

o    I will then turn the call over to Dr. Stuart Collinson, CEO of Aurora, who
     will describe Aurora's technology and discuss the transaction from the
     perspective of Aurora's objectives for integration.

o    Dr. Joshua Boger will then discuss the strategic near-term and long-term
     importance of the transaction to Vertex

o    Then we will open up the call to your questions


Page 3


DEAL TERMS

o    I will begin today's call by reviewing the terms of the transaction:

o    As discussed in today's press release, Vertex will acquire Aurora in a
     stock-for-stock transaction that values Aurora at $592 million.

o    Each share of Aurora will convert into 0.62 shares of newly issued Vertex
     common stock. Based on Friday's closing prices, the fixed exchange ratio
     implies a per share price of $24.34 per share of Aurora common stock, a
     44.4 percent premium to the closing price of $16.85 on April 27, 2001.

o    In connection with the merger agreement, Vertex expects to issue
     approximately 14 million shares of common stock in exchange for Aurora's
     common stock. The transaction will be structured as a tax-free share
     exchange and is intended to be accounted for as a pooling of interests.

o    The terms of the agreement have been approved by the Boards of Directors of
     both Vertex and Aurora. The Directors and Officers of both companies have
     also agreed to vote their shares in favor of the merger.


Page 4


o    The merged company will be named Vertex Pharmaceuticals Incorporated.
     Aurora will operate as a wholly-owned subsidiary of Vertex, and will retain
     the Aurora name. Vertex will seek to maintain and enhance Aurora's existing
     relationships with corporate partners, disease foundations and research
     institutions.

o    The merger is subject to approval by Vertex and Aurora shareholders, and
     also subject to Hart-Scott-Rodino clearance and other conditions.

o    The deal is expected to close in the third quarter of 2001.

GUIDANCE/OVERVIEW OF TRANSACTION

o    In terms of the impact of this transaction on our financial guidance...

     o   On Vertex's first quarter conference call on April 24, we gave guidance
         for a net loss for the full year of 2001 in the range of $60-$65
         million dollars. The transaction, excluding merger-related expenses, is
         not expected to materially affect these previously announced net
         operating results projections.

RATIONALE FOR TRANSACTION


Page 5


o    I will now describe the strategic rationale of the transaction...

o    Today's agreement between Vertex and Aurora brings together two companies
     with outstanding and highly complementary technology platforms, and
     fulfills several key criteria in accordance with Vertex's strategic
     objectives in 2001.

OVERVIEW OF TRANSACTION

o    Many of you are familiar with Vertex's industry-leading efforts to discover
     small molecule drugs targeting caspase and kinase gene families. Our
     efforts in these two enzyme families are collectively supported by more
     than $1 billion in committed payments from partners, and have the potential
     to produce major treatments for heart disease, stroke, cancer, rheumatoid
     arthritis, and many other serious diseases.

o    A key goal for Vertex is--through internal growth, technology licensing,
     and acquisition--to enhance our leadership position in these families, as
     well as expand rapidly our research into additional gene families where we
     believe there is substantial therapeutic opportunity and where we can
     effectively apply our technology expertise.

o    The agreement to acquire Aurora represents a step toward fulfillment of
     this goal. As will be discussed by both Dr. Collinson and Dr. Boger, Aurora
     brings unique technological and organizational assets to bear on several of
     the most important and


Page 6


     target-rich areas of the genome. The merger will provide Vertex with
     substantial expertise in important new gene families such as GPCRs and ion
     channels, families which collectively account for the targets for half of
     the top 100 marketed drugs.

o    On a pro forma basis, the combined company will be strong financially with
     approximately $800 million in cash, and will have approximately 800
     employees. The acquisition of Aurora will contribute to our revenue growth,
     and the aggregate revenue projections for the two companies in 2001 are
     approximately $180 million. The acquisition will also enhance our
     intellectual property estate, and accelerate our drug discovery and early
     development capabilities.

HAND OFF

o    It is now my pleasure to introduce Dr. Stuart Collinson, Chief Executive
     Officer and Chairman of the Board of Aurora Biosciences.

FULFILLMENT OF AURORA'S STRATEGIC OBJECTIVES - DR. STUART COLLINSON

o    Thank you, Lynne.  It is a pleasure to be here.

o    We at Aurora are THRILLED to be joining forces with Vertex. Simply stated,
     this merger combines Aurora's biology capabilities with Vertex's
     chemogenomics platform to create a drug discovery powerhouse. Each company
     brings to the merger:


Page 7


     o    a long history of successful partnerships with leading pharmaceutical
          companies;
     o    a strong intellectual property position;
     o    a track record of outstanding achievement by creative and
          highly-respected people; and
     o    a strong balance sheet

As I discuss the merger from Aurora's perspective, I will touch upon these
points in some detail.

FULFILLMENT OF AURORA'S STRATEGIC OBJECTIVES

o    Today's announcement represents a major milestone in Aurora's corporate
     history, and a rapid fulfillment of our objective to enhance the discovery
     capabilities of our technology base. Through this merger agreement, Aurora
     joins forces with a world class organization with a well-developed
     discovery and clinical development infrastructure. We gain the opportunity
     to immediately and dramatically apply our core strengths in ultra high
     throughput screening and custom assay development to do the following:

     o    accelerate design and discovery of multiple lead chemical classes of
          compounds in a number of major target-rich gene families


Page 8


     o    optimize the safety, pharmacokinetics and pharmacodynamics of lead
          drug candidates, and
     o    establish proof-of-concept for drug candidates in early clinical
          development

STRENGTH OF COMBINED COMPANY


o    I'd like to provide a brief background on Aurora to put in context how the
     proposed merger represents an achievement of our strategic business
     objectives, and how we anticipate that the proposed merger will take
     Aurora's capabilities to a new level.

o    Aurora was founded in 1995 to accelerate and enhance the discovery of new
     medicines using proprietary fluorescence assays which have been
     miniaturized and automated using proprietary microfluidics and robotics.

o    The subsequent development of Aurora's ultra high-throughput screening
     platform, together with a wide range of innovations in cell-based assay
     development and new fluorescent assay technologies, enabled the company to
     become a recognized industry leader in cell biology, and a research and
     development partner of choice to the pharmaceutical industry in the period
     1996-2000. In that period we signed more than 25 agreements with Merck,
     Bristol-Myers Squibb, Pfizer, the Cystic Fibrosis Foundation and other
     leading organizations. Our revenue base grew from $2 million in 1996 to $64
     million in 2000 (excluding PanVera), and Wall Street consensus projections
     are for $90 million in revenues (including PanVera) in 2001.


Page 9


o    In the early days of Aurora, the revenue strongly reflected the development
     of the ultra high-throughput screening platform technology. Today, the
     majority of the business comes from drug discovery collaborations, which
     draw on Aurora's integrated biology, instrumentation, and intellectual
     property licensing.

FULFILLMENT

o    Early in 2001, Aurora articulated a strategic objective of further
     advancing our business model and building an internal drug discovery
     capability around our strengths in ultra high-throughput screening and
     cell-based and biochemical assay development. By expanding our capabilities
     into the drug discovery arena, our goal is to capture a greater portion of
     the downstream value created by our technology platform.

o    The agreement announced today represents an early and dramatic fulfillment
     of this strategic objective. The integration of our technology base with
     Vertex's chemogenomics platform creates a company with proven drug
     discovery capabilities and unique assets and advantages in multi-target
     gene families.

STRATEGIC FIT; NEAR AND LONG-TERM SHAREHOLDER VALUE

o    We believe this merger achieves an excellent strategic fit that will fully
     capture the potential of our technology platform:


Page 10


     o    Vertex has a proven track record in drug discovery, with one marketed
          drug and 12 drug candidates in development
     o    Vertex has a demonstrated ability to solve difficult drug discovery
          problems, and succeed in highly competitive areas of small molecule
          drug discovery.
     o    Most importantly, Vertex has accomplished its success in drug
          discovery by being masterful integrators of technology, as well as
          inventors of proprietary technology. This aspect of Vertex in
          particular indicates to us that the integration of our technologies
          with theirs will have powerful results. The combined company will have
          more than 400 United States patents issued or pending, including
          proprietary technologies and chemical classes of compounds that cover
          drug candidates. The combined capabilities of the merged company
          should accelerate the capture of intellectual property in all aspects
          of drug discovery.

o    For Aurora shareholders, this agreement provides both near and long-term
     value creation potential. The share price premium agreed to as part of the
     merger represents one small component of this potential. The ability to be
     part of Vertex Pharmaceuticals provides Aurora shareholders with an
     opportunity to achieve long-term returns as well.

o    As Joshua will discuss, we believe that Aurora's technologies will have an
     immediate and highly positive impact on Vertex's efforts in the kinase and
     caspase gene families,


Page 11


     and on other programs from the discovery stage right through to early
     clinical development. Additionally, Aurora's expertise in GPCRs and ion
     channels will enable the combined company to rapidly ramp up drug discovery
     efforts in these areas of major medical opportunity. We believe that the
     acceleration of drug discovery in gene families will significantly enhance
     the combined company's product and business development opportunities.

SUMMARY

o    Both companies have a strong track record as successful collaborators. This
     agreement is designed to preserve and enhance existing relationships, and
     we will continue to supply and support innovative assays and
     instrumentation to current and new clients in the pharmaceutical and
     biotech industries. Aurora has maintained the highest degree of integrity
     with respect to managing partners who are also competitors, and we will
     continue to maintain this standard as a subsidiary of Vertex.

o    At the same time, the merger provides a framework for new, broad-based
     partnerships based on Aurora and Vertex's drug discovery capabilities in
     gene families.

o    Since 1995, we have successfully transformed Aurora from a leading
     technology provider into an integrated drug discovery company. The merger
     reflects the growth


Page 12


     of our business and capabilities, and the potential we can achieve as part
     of the Vertex R&D organization.

o    I will now turn the call over to Joshua Boger.

DRIVERS OF THE TRANSACTION - DR. JOSHUA BOGER

o    Thank you, Stuart.

o    We at Vertex are tremendously excited about today's merger agreement, which
     provides Vertex immediate and substantial drug discovery presence in new
     gene families, and enhances our overall drug design and development
     capabilities. Together with Aurora, we expect to tap the product creation
     potential of the human genome as never before.

o    I'll reiterate what Stuart said about the strengths of the combined
     company. The merger of Aurora and Vertex brings together two companies
     with:
     o    an established track record as successful collaborators based on
          unique drug discovery capabilities;
     o    broad intellectual property portfolios based on proprietary expertise
          and drug candidates;
     o    highly talented people at the top of their fields; and
     o    a strong financial position and a tradition of prudent financial
          management


Page 13


o    I'll discuss these points in some detail as I discuss the merger agreement
     in the context of Vertex's drug discovery and business objectives.

FULFILLMENT OF GOALS

o    This merger fulfills two major milestones that we have emphasized
     increasingly in our external communications in recent months, which are:

     1.   To acquire complementary technologies that we can integrate into our
          platform to accelerate drug design in gene families
     2.   to extend our leadership position in gene family-based drug discovery
          by expanding into additional gene families

EVALUATION OF OPPORTUNITIES

o    INTERNALLY, we have accomplished a significant scale-up of our research
     efforts in gene families, and most notably in the kinase gene family, which
     has an estimated 500 targets. With research support from Novartis, we are
     on schedule with our hiring plan, and we are simultaneously tackling
     multiple kinase targets spanning a broad base of therapeutic areas. We are
     on track to select 1-2 novel kinase inhibitors for preclinical development
     this year.


Page 14


o    EXTERNALLY, Vertex management has exhaustively reviewed dozens of merger
     and acquisition opportunities over the course of 18 months; we set a very
     high threshhold in terms of the quality of the people, the quality of the
     science, and potential for near- and long-term contribution to Vertex's
     drug discovery, development, and commercial goals.

o    In particular, a major focus has been on technology opportunities that will
     enhance our leadership position in the kinase and caspase gene families, or
     that will enable us to rapidly ramp up our research efforts in additional
     gene families that are rich in targets and therapeutic opportunity.

o    At the same time, we sought opportunities that would have a minimal effect
     on our projected operating results going forward.

o    The agreement to acquire Aurora represents a highly successful conclusion
     to this search and evaluation process. We believe Aurora fulfills every one
     of our major acquisition criteria, and represents an excellent strategic
     fit for Vertex. In particular, the acquisition of Aurora will significantly
     broaden our talent pool, contribute to our revenue growth, increase our
     cash position, enhance our intellectual property estate, and accelerate our
     drug discovery capabilities.

AURORA BENEFITS


Page 15


o    Aurora is the right opportunity for Vertex and it comes at the right time.
     Let me explain why:

     o    Vertex is in a unique position to successfully translate genomic
          discoveries into clinically and commercially important drugs. We have
          oriented our research approach to capture the small molecule product
          opportunity of major, target-rich areas of the genome, using a
          strategy of parallel drug design.

     o    Vertex's approach, which we have termed chemogenomics, is designed to
          accelerate drug discovery and capture large amounts of product-based
          intellectual property around highly promising targets.

     o    Our approach has drawn the support of major pharmaceutical companies,
          for example Novartis, who have announced some very dramatic financial
          commitments.

OUTPUT FROM CHEMOGENOMICS

     o    Most importantly, we are demonstrating that chemogenomics WORKS. We
          are seeing the first drug candidates taking shape from this approach,
          and our intellectual property capture is increasing. We expect to
          advance 5 or more new


Page 16


          drug candidates into development in 2001, including novel kinase
          inhibitors and novel caspase inhibitors, representing the first output
          from our extensive efforts underway in these gene families.

     o    Our challenge now is expand into additional gene families as rapidly
          as possible and with minimal financial risk, to use Vertex's
          capabilities to fully realize the potential of its chemogenomics
          platform to create medically and commercially important small molecule
          drugs.

     o    The integration of Aurora's technology and expertise enables us to
          achieve this expansion, and also has major benefits to our existing
          discovery and development efforts in kinases and caspases, which I'll
          now explain in some detail.

AURORA BENEFITS

o    Aurora is recognized throughout the industry as a leader in cell-based
     assay development, ultra high-throughput screening and instrumentation, as
     evidenced by its impressive roster of corporate partners and strong revenue
     line.

o    Aurora has developed unique and proprietary capabilities in several major
     gene families, and let me just touch upon two of them: g-protein coupled
     receptors and ion channels.


Page 17


o    These gene families are both proven in terms of druggable targets, and also
     represent target-rich areas which may allow the treatment of a wide variety
     of serious diseases. More than half of the top 100 marketed drugs target
     proteins in one of these two gene families.

o    Some examples of Aurora's assets and capabilities in these gene families
     include:

     1.   the rapid development of cell-based assays for screening of compounds
          targeting g-protein coupled receptors and ion channels. As of year-end
          2000, Aurora had assays up and running that target more than 150
          different targets, with the goal of adding 200 more in 2001;
     2.   proprietary assays that measure differential g-protein receptor
          activity, which can be key to elucidating gene function; and
     3.   a patented technology platform that measures--with precision and
          accuracy unequaled anywhere in the industry--the activity of drug
          candidates directed at ion channels.

o    Integrated with Vertex's strengths in medicinal chemistry, combinatorial
     and computational chemistry, and information technologies, we believe
     Aurora's capabilities will enable us to efficiently build towards a
     comprehensive leadership position in drug discovery in these families. We
     expect Aurora's technologies will


Page 18


     increase and accelerate our ability to discover and file patents on drug
     candidates in these families in the near term.

o    GPCRs and ion channels are two particularly striking examples of the
     scalability of the combined company's technology platform. Aurora's
     proprietary technology base, however, is quite broad, and applicable to a
     variety of gene family opportunities, including for example proteases and
     phosphatases, two other areas where Vertex also has existing complementary
     scalable capabilities.

o    The acquisition of Aurora will provide enhanced product and business
     development opportunities going forward, and will enable Vertex to more
     rapidly leverage its drug discovery strengths with broad-based
     collaborations in gene families. A key near- and long-term impact of the
     Aurora acquisition will be new multi-target gene family partnerships. These
     partnerships will be a key catalyst enabling Vertex to fulfill the full
     product creation potential of its chemogenomics platform in additional gene
     families.

o    Aurora's technological capabilities also bring immediate benefits to
     Vertex's existing efforts in the kinase and caspase gene families. In
     particular, we believe that Aurora's technologies will help us to meet or
     exceed our drug discovery and development goals in Vertex's collaboration
     with Novartis. To be specific, we believe that:


Page 19


     1.   Aurora's target validation technologies, including its proprietary
          GenomeScreen Technology, will facilitate target selection in kinases
          and assist with elucidating the function of novel kinases;
     2.   Aurora's ultra high throughout screening platform will accelerate the
          design and optimization of lead classes of kinase inhibitors by
          providing cell activity information which can be fed into our
          proprietary computational chemistry algorithms;
     3.   Aurora's predictive pharmacology technologies, including its novel and
          proprietary high throughput cell-based assay approaches, will help to
          determine the toxicology and pharmacodynamic profile of lead compounds
          in advance of clinical testing;
     4.   Aurora's emerging proteomic technologies, which provide highly
          sensitive assessments of changes in protein activity in cell and
          tissue samples, combined with our own proteomics efforts will help us
          to obtain strong clinical proof-of concept information in the earliest
          stages of clinical development

o    I'd like to emphasize that kinases represent one particularly strong
     application of Aurora's technologies, but we believe these technologies
     will have an impact across our pipeline. Given the high degree of
     technological complementarity between the two companies, our goal will be
     to propagate Aurora's capabilities as fully as possible across Vertex
     discovery and development programs.

AURORA BENEFITS; SHORT AND LONG-TERM IMPACT


Page 20


o    Aurora has a strong track record of scientific excellence and creativity,
     and strong management. Our goal is to continue to cultivate Aurora's
     position at the forefront of innovation in cell biology, high-throughput
     screening, and functional genomics while maximizing the capabilities of the
     combined organization.

o    Following the merger, Aurora will operate as a wholly-owned subsidiary of
     Vertex, and will retain the Aurora name. Stuart Collinson, CEO of Aurora,
     will join Vertex's Board of Directors following the close of the merger.
     Harry Stylli, Ph.D, Aurora's Senior Vice President of Commercial
     Development, will be President of the Aurora subsidiary.

SHORT AND LONG-TERM IMPACT

o    In summary, the merger with Aurora will have short-, medium- and long-term
     benefits to Vertex.

o    The merger will immediately Vertex's expand research into new gene
     families, while minimizing financial risk. The Aurora acquisition will
     facilitate Vertex's involvement in several multi-target collaborations
     focused on gene families. Each of these partnerships will have a large team
     of scientists dedicated to it, generating drug


Page 21


     candidates and intellectual property that will enable Vertex to establish a
     leadership position in the fields we enter.

o    In addition, integration of Aurora's technologies will enable us to
     increase the productivity of our existing research and development
     programs.

o    We are already seeing a significant ramp-up in our productivity as a result
     of our gene-family efforts. We believe that progress in our current
     clinical pipeline, together with the ramp-up of our gene family efforts,
     will enable Vertex to achieve its long-term goal to be at the level where
     we - along with our partners - can bring 10 drug candidates into
     preclinical development each year, a rate of output that will support the
     progression of 2-3 drug candidates to the NDA stage every year. This is a
     level of productivity that is comparable in aspiration to that of today's
     largest multinational pharmaceutical companies.

VERTEX LONG-RANGE VISION

o    The drivers for Vertex in the near term are:

     1)   To be the best in the industry at drug discovery;
     2)   To grow organically and by acquisition to further define and enhance
     our competitive advantage;
     3)   To bring important drugs to the market independently and with
     partners, and


Page 22


     4)   To advance our business without sacrificing the path to profitability.

     The Aurora organization shares this vision with us. Our goal is to do all
     of these while keeping intact the entrepreneurial spirit of our
     organization.

o    We look forward to pursuing our vision together with Aurora in the years
     ahead.

I'll now turn the call back to Lynne.

Q&A- LYNNE BRUM

We will now open the call to your questions

Q&A PERIOD

IF YOU WOULD LIKE TO ASK QUESTIONS DURING THIS TIME, PRESS NUMBER ONE ON YOUR
KEYPAD. QUESTIONS WILL BE TAKEN IN THE ORDER THAT THEY ARE RECEIVED. IF YOU
WOULD LIKE TO WITHDRAW YOUR QUESTION, PRESS THE POUND KEY.


Page 23



                           **************************

Investors and security holders are advised to read the joint proxy
statement/prospectus regarding the proposed merger when it becomes available,
because it will contain important information. Such joint proxy
statement/prospectus will be filed with the Securities and Exchange Commission
by Vertex and Aurora. Investors and security holders may obtain a free copy of
the joint proxy statement/prospectus (when available) and other documents filed
by Vertex and Aurora at the Securities and Exchange Commission's web site at
www.sec.gov. The joint proxy statement/prospectus and such other documents may
also be obtained from Vertex by directing such request to Vertex
Pharmaceuticals, 130 Waverly Street, Cambridge, MA 02139, Attn: Investor
Relations, tel: (617) 577-6000; e-mail: InvestorInfo@vpharm.com. The joint proxy
statement/prospectus and such other documents may also be obtained from Aurora
by directing such request to Aurora Biosciences, 11010 Torreyana Road, San
Diego, CA 92121, Attn: Investor Relations, tel: 858-404-6600; e-mail:
ir@aurorabio.com.

                           **************************

THE FOLLOWING IS THE TEXT OF SLIDES FROM A SLIDE SHOW PRESENTED TO ANALYSTS AND
OTHERS ON APRIL 30, 2001.



                    [VERTEX LOGO] [AURORA BIOSCIENCES LOGO]



                Uniquely Positioned to Accelerate Drug Discovery



                                   APRIL 2001


Safe Harbor Statement

      Various remarks that we may make about future expectations, plans and
    prospects for Vertex and Aurora constitute forward-looking statements for
       purposes of the safe harbor provisions under The Private Securities
    Litigation Reform Act of 1995. Actual results may differ materially from
   those indicated by these forward-looking statements as a result of various
      important factors, including those discussed in each of Vertex's and
    Aurora's Form 10-K for the fiscal year ended December 31, 2000, which are
                              on file with the SEC.



Transaction Summary

SUMMARY OF PROPOSED TERMS


Companies                          Vertex Pharmaceuticals and
                                   Aurora Biosciences
- --------------------------------------------------------------------------------
Transaction Value                  $592 million
- --------------------------------------------------------------------------------
Structure/ Intended                Tax-free stock-for-stock merger/
Accounting Treatment               Pooling-of-interests
- --------------------------------------------------------------------------------
Name of Merged Entity              Vertex Pharmaceuticals
- --------------------------------------------------------------------------------
Exchange Ratio                     0.62 Vertex shares for each Aurora share
- --------------------------------------------------------------------------------
Ownership of                       Vertex 81.5%, Aurora 18.5%; proforma
combined entity                    fully diluted
- --------------------------------------------------------------------------------
Shareholder Approval               Required for both companies
- --------------------------------------------------------------------------------



Strategic Rationale

        The agreement unites Aurora's industry-leading assay development,
    screening, and cell biology capabilities that drive their target-focused
         drug discovery efforts, with Vertex's integrated drug discovery
    expertise, creating a comprehensive, scalable platform for systematically
         accelerating drug candidate output in target-rich gene families



Outstanding Product Creation Capability

AURORA                                                  VERTEX

Cell biology                                            Drug discovery
Screening                                               Chemogenomics
Ultra high-throughput systems                           Drug development
Target families                                         Broad pipeline
Cellular markers for clinical
proof-of-concept                                        Commercialization
                                                        Financial strength
Partners                                                Partners


                   COMPETETIVE ADVANTAGE: PRODUCT DEVELOPMENT



Immediate Benefits

     o    Accelerate drug discovery

     o    Entry to additional target rich gene families

     o    Decrease attrition rate in drug development

     o    Expand base of commercial partnerships

     o    Expand organization without increasing burn



Aurora Targets, Screens and Therapeutic Areas

Ion Channels             25 Targets, 10 screens
                         Cardiovascular, CNS, pain, cystic fibrosis

Receptors                100 Targets, 20 screens
                         CNS, inflammation, pain, antimicrobial

Enzymes                  100 Targets, 30 screens
                         Cancer, inflammation, neurodegenerative

Gene Expression          15 Targets, 8 screens
                         Cancer, immune, metabolism



Expand Chemogenomics Into Multiple Target Classes


   [GRAPHIC - GROUPING OF MULTIPLE TARGET CLASSES FOR EXPANDED CHEMOGENOMICS]



Target Classes of Marketed Drugs*

Vertex Alone

Enzymes Ion Channels GPCRS Other** East 36 6 50 8
Vertex with Aurora
Enzymes Ion Channels GPCRS Other** East 36 6 50 8
*Based on top 100 marketed drugs **vaccines, imaging agents, and coagulation factors Vertex Facts at a Glance Headquarters: Cambridge, MA IPO: 1991 CEO: Joshua Boger, Ph.D., CEO AND CHAIRMAN Employees: 475 full-time (March 2001) Business: Discovery, development and commercialization of small molecule pharmaceuticals 2000 Revenue: $78 million 2000 Net Loss: $40 million 2000 Loss/share: $0.73 Cash Position: $685 million (Q1 `01) Key Competencies/Value Drivers Vertex Capabilities o Chemogenomics platform driving parallel drug discovery in gene families o Marketed product - Agenerase(R) for HIV o Broad product pipeline of 12 product candidates o 5 or more new product candidates anticipated in 2001 o Significant collaborations with superior financial and downstream terms--(eg. Novartis, Serono, Aventis) o Strong financial position with >$685 million o Experienced management team Four Therapeutic Areas; 12 Drug Candidates
Product Indication Dev. Stage Partners Infectious Disease Agenerase(R) HIV Market GSK/Kissei VX-175 HIV Phase III GSK merimempodib (VX-497) HCV Phase II Cancer Incel(TM) MDR Phase II VX-853 MDR Phase I/II Inflammation & Autoimmune VX-745 Rheum. arthritis (RA) Phase II Kissei Disease VX-850 & VX-702 Inflammation, cardio Preclinical Kissei pralnacasan (VX-740) RA, OA, cardio Phase II Aventis VX-765 Inflammation, cardio Preclinical VX-148 Autoimmune,antiviral Phase I VX-944 Autoimmune,antiviral Preclinical Neurological Disease timcodar Diabetic neuropathy Phase II Schering AG
Aurora Facts at a Glance Headquarters: San Diego, CA IPO: 1997 CEO: Stuart J.M. Collinson, Ph.D, CEO, PRESIDENT AND CHAIRMAN Employees: 350 full-time (March 2001) Business: Technologies, products and services to accelerate the discovery of new medicines 2000 Revenue: $64 million 2000 Net Income: $5.7 million 2000 EPS: $0.20 Cash Position: $106 million (YE `00) Aurora Business Focus [AURORA LOGO]
Discovery Biology Discovery Solutions Discovery Systems o Assay data-driven o Solutions for o Invent, develop, approach drug discovery manufacture and integrate - Miniaturized - Genome Screen/ instrumentation functional assays GeneBLAzer and software applicable to all systems for drug major target classes - Voltage / Ion discovery Probe Reader - Cell-based and (VIPR) o Systems include biochemical formats - UHTSS - PhosphoryLIGHT - Automated Master - Rapid assay Compound Store development - Fluorescent - Voltage Ion Probe Proteins (GFPs) Reader - Applicability to orphan targets - Protein purification - Proteomics
Key Competencies/Value Drivers Aurora Capabilities o Drug discovery solutions based on proprietary genomic, assay and automated system technologies o Internal target-centric drug discovery programs can accelerate small molecule therapeutic programs focused on GPCRs and Ion channels o Industry leader in custom assay development, ultra high-throughput screening o Broadly enabling technology with initiatives in multiple gene families o Compound profiling of ADME/Tox properties o Experienced scientific team Key Competencies/Value Drivers Merger Benefits o Broad product development and partnering opportunities, with enhanced technology and discovery strengths - Pipeline - 25+ partners, broad based revenue stream - Formidable IP in certain gene families - Technology suitable for all major classes of druggable targets o Vertex can extend Aurora's assets further down value chain immediately o Vertex can expand and enhance gene family efforts immediately BUSINESS GOAL: MORE SCALE, MORE DRUG CANDIDATES, MORE COLLABORATIONS AND MORE VALUE, WITHOUT ADDITIONAL BURN RATE World Class Partners- Vertex [GRAPHIC - COMPANY LOGOS OF VERTEX PARTNERS] World Class Partners- Aurora [GRAPHIC - COMPANY LOGOS OF AURORA PARTNERS] World Class Partners- Vertex and Aurora [GRAPHIC - COMPANY LOGOS OF VERTEX AND AURORA PARTNERS] Commitment to Drug Discovery o Vertex's goal: Expand into additional target-rich gene families using existing technology base and through acquisition and integration of key value-added technologies, resources and assets o By 2005, achieve productivity level of 10 NCEs into development per year, creating opportunity for 2-3 NDAs in 2005-2010 The Post-Genomic NCE Machine Industry Leading Drug Discovery o Vertex: Chemogenomics, structure-based drug design, multi-target gene family drug discovery o Aurora: Ultra-high-throughput screening, assay development Complementary Strategy o Vertex and Aurora: Combine scalable approaches to accelerate drug discovery to maximize product creation based on gene families: Big Biology + Chemogenomics Technological Fit o Vertex: Gains access to leading biology capabilities in relevant gene families o Aurora: Gains immediate fulfillment of downstream goals of Big Biology initiative Common Goals o Vertex and Aurora: Leader in drug discovery and development: Creating the Post-Genomic NCE Machine Vertex Inside and Out [GRAPHIC - VERTEX PRODUCTS AND PRODUCT PARTNERS] [VERTEX LOGO] [AURORA BIOSCIENCES LOGO] Uniquely Positioned to Accelerate Drug Discovery APRIL 2001 ************************** Investors and security holders are advised to read the joint proxy statement/prospectus regarding the proposed merger when it becomes available, because it will contain important information. Such joint proxy statement/prospectus will be filed with the Securities and Exchange Commission by Vertex and Aurora. Investors and security holders may obtain a free copy of the joint proxy statement/prospectus (when available) and other documents filed by Vertex and Aurora at the Securities and Exchange Commission's web site at www.sec.gov. The joint proxy statement/prospectus and such other documents may also be obtained from Vertex by directing such request to Vertex Pharmaceuticals, 130 Waverly Street, Cambridge, MA 02139, Attn: Investor Relations, tel: (617) 577-6000; e-mail: InvestorInfo@vpharm.com. The joint proxy statement/prospectus and such other documents may also be obtained from Aurora by directing such request to Aurora Biosciences, 11010 Torreyana Road, San Diego, CA 92121, Attn: Investor Relations, tel: 858-404-6600; e-mail: ir@aurorabio.com. ************************** THE FOLLOWING IS THE TEXT OF QUESTIONS AND ANSWERS DISCUSSED ON A TELEPHONE CONFERENCE WITH ANALYSTS AND OTHERS HELD ON APRIL 30, 2001. VERTEX PHARMACEUTICALS INCORPORATED - -------------------------------------------------------------------------------- Q & A Vertex Acquisition of Aurora - -------------------------------------------------------------------------------- 1. Key Messages - -------------------------------------------------------------------------------- o Rationale of the deal: o Leading cell based biology + leading chemistry/proven discovery = next generation pharmaceutical company/novel new medicines o Powerful IP o Great people / know how o Strong balance sheets o Leading collaborations o Vertex will acquire Aurora in a stock-for-stock transaction. The fully-diluted equity value of the deal is approximately $592 million. Each share of Aurora will convert into shares of newly issued Vertex common stock at a fixed ratio of 0.62 shares of Vertex stock for each share of Aurora stock. Based on the closing price of Vertex stock of $39.25 on April 27, 2001, the fixed exchange ratio implies a price of $24.34 per Aurora share, a 44 percent premium to the closing price of $16.85 on April 27, 2001. Vertex expects to issue a total of approximately 14.0 million shares of common stock in exchange for Aurora's outstanding common stock, and Aurora options will be equitably converted to Vertex options. As of December 31, 2000, Aurora had approximately $100 million in net cash. On a pro forma (fully -diluted) basis, Aurora's shareholders will own approximately 18.5% of Vertex. o The merger fulfills one of Vertex's near-term goals, which is to acquire complementary products, capabilities and technologies that will enhance our drug discovery capabilities. The achievement of this goal, in turn, will position us to achieve another corporate goal, that of applying our chemogenomics platform to additional multi-target gene families. o The agreement will unite Aurora's industry-leading assay development, screening and cell biology capabilities with Vertex's integrated drug discovery expertise, creating a comprehensive, scalable platform for systematically accelerating drug candidate output in target-rich gene families. o The combination of Vertex's and Aurora's technology and expertise is expected to increase the flow of drug candidates into development, accelerate the creation of a broad intellectual property estate, and provide enhanced opportunities for major drug discovery, development and commercial alliances. o Aurora's suite of technologies has the potential to accelerate target selection, lead generation and optimization, drug candidate selection, and the establishment of clinical proof-of-concept across multiple gene families. By integrating Aurora's capabilities within Vertex's chemogenomics platform, we believe we will be able to rapidly expand research into major new gene families. 1 o In addition, Aurora's proteomics and assay development expertise are broadly applicable to our clinical programs, and will enable us to more rapidly establish the therapeutic profile of our development-stage drug candidates. o The combined company's integrated technology platform will be supported by more than 25 collaborative and licensing agreements with research institutions and major pharmaceutical companies. Existing and new corporate collaborations will continue to be important sources of revenue for the combined company. o In short, we get more scale, more drug targets, more collaborations, and more value to shareholders, without adding to our burn rate and without significantly diluting our ownership position. - -------------------------------------------------------------------------------- 2. Positioning of Merger Benefits and of the Combined Company - -------------------------------------------------------------------------------- Q: WHAT IS THE STRATEGY BEHIND THE PROPOSED MERGER? A: We believe this merger will create the premier fully-integrated drug discovery and development company in the industry. The agreement unites Aurora's industry-leading cell biology capabilities with Vertex's integrated drug discovery expertise, creating a comprehensive, scalable platform for systematically accelerating drug candidate output in target-rich gene families. The combined company will have a marketed drug, a powerful near-term product pipeline, over 25 collaborative and licensing agreements and a drug discovery enterprise uniquely positioned to rapidly exploit the drug discovery opportunities created by the genomic revolution. In addition, the acquisition of Aurora will add approximately $100 million to Vertex's cash balance and is expected to approximately double Vertex's annual revenue generation. Q: WHY IS THIS AN IMPORTANT DEAL FOR VERTEX? A: We are at the one-year anniversary of our deal with Novartis. Through this experience, we are generating demonstrable proof that chemogenomics accelerates drug discovery and increases intellectual property in gene families. With this transaction, we will enhance our drug discovery capabilities into other gene families such as GPCRs, ion channels and proteases that are of critical interest to us and to future partners. This is one of the main drivers for this transaction. Q: WHY IS VERTEX DOING THIS DEAL NOW? A: We believe that even with a 44.4% premium over Aurora's closing share price of $16.85, Aurora is a compelling value. We also note that on a combined company basis, Vertex current shareholders will own approximately 81.5% of the combined company. Moreover, we are well-positioned to scale chemogenomics to additional target families, on which Aurora has done extensive work. 2 Q: WHY ARE YOU BUYING AURORA RATHER THAN COLLABORATING WITH THEM? A: In an acquisition, we will have access to the full talent pool at Aurora. We'll be able to apply their technologies in a way that hasn't been done before. We expect that Aurora will be a free-standing business that will continue to work with pharmaceutical companies and other life sciences companies, but elements of their business also will be rapidly integrated into our technology platform. In addition, Aurora's technologies can help us immediately across several programs. We believe there is tremendous value in integrating their technologies, not just adding them. Q: DOES THIS TRANSACTION HAVE THE POTENTIAL TO SHIFT YOUR BUSINESS FOCUS INTO BEING A TECHNOLOGY/INSTRUMENTS SERVICES COMPANY? A: Vertex has a clear product discovery and commercialization business model and believes the addition of Aurora will benefit this model. The combined company has an industry leading product pipeline and will continue to grow and advance the development of this pipeline. Vertex anticipates that the combined company will be capable of dramatically accelerating the creation and, perhaps the expansion, of high value, broad-based third party R&D collaborations that focus on specific gene families and other target clusters, while continuing to build, even accelerate, as previous guidance has indicated, a significant proprietary product pipeline. Aurora's UHTSS platform business will continue to be an important element of the Aurora subsidiary's business. Q: DOESN'T VERTEX ALREADY HAVE EXISTING CAPABILITIES AND EXPERTISE IN ASSAY DEVELOPMENT AND SCREENING? WHY DOES IT NEED AURORA? A: Yes, Vertex has expertise in assay development and screening. We have agreed to acquire Aurora because we saw the opportunity to add extremely complementary technology to our platform that will significantly enhance our drug discovery capabilities and enable us achieve our goal of having the capability of generating 2-3 NDA's on an annualized basis starting in the 2005-2010 timeframe. Q: DOES VERTEX PLAN TO REMAIN AS A PLAYER IN THE INSTRUMENTATION INDUSTRY? A: Vertex expects that Aurora will continue to conduct its business as planned once the merger is completed. This business has been an important and valuable component of Aurora's integrated product and services offerings to its customers. Q: ARE THERE ANY PLANS TO SPIN OUT PIECES OF THE BUSINESS? A: There are no definitive plans to spin out pieces of the business at this time. Q: WHAT WILL THE NEW COMPANY BE CALLED? A: The combined company will be called Vertex Pharmaceuticals, Inc. Aurora will be a wholly owned subsidiary of Vertex Pharmaceuticals, operating under the name Aurora. 3 Q: CAN YOU PROVIDE SOME BACKGROUND ON AURORA? A: Aurora is a leader in cell assay technology. Aurora was founded in 1995 and is located in San Diego, CA. The company has approximately 350 full-time employees. In addition to its proprietary fluorescent cell assay technology, the company has a leadership position in ultra high throughput screening, and has established biological expertise and intellectual property in a variety of gene families and other target areas, which the company has leveraged into over 25 partnerships with leading life science entities. Q: HOW WILL AURORA BE INTEGRATED, LEGALLY AND OPERATIONALLY, AND HOW DOES THIS EFFECT EXISTING CUSTOMERS? A: Aurora will be merged into Vertex as a wholly-owned subsidiary and will continue to operate under the Aurora name. Operationally, we will continue to offer to Aurora's existing and future partners all of Aurora's product and service offerings, but anticipate that Vertex's drug discovery and development capabilities could provide additional value-added products and services. Q: WON'T VERTEX BE VIEWED AS A COMPETITOR TO AURORA'S CUSTOMERS IN THE AREAS OF DRUG DISCOVERY SERVICES? A: Just as we have proven to our existing partners that we can become integral to their drug discovery efforts while maintaining the IP and R&D efforts distinct from collaborative efforts without compromising the relationship's integrity, we believe that we can do the same with Aurora's relationships, and, perhaps provide even more R&D support. Vertex will respect the confidentiality of existing Aurora customers. Q: HOW DO YOU THINK AURORA'S CUSTOMERS WILL REACT TO THE ACQUISITION? A: Aurora has an excellent track record of customer satisfaction and retention, as exhibited by the strengthening of its relationships over time through renewals and service extensions with leading pharmaceutical and biotechnology companies. We anticipate that Aurora's customers will view the merger as a positive in that the combined company will be able to continue its commitments to the existing contracts, and, perhaps extend the relationship further depending on their particular needs. Q: CAN YOU DESCRIBE THE BUSINESS MODEL OF THE COMBINED COMPANY? A: Vertex's business model is a high value model. We anticipate that the combined company will be capable of dramatically accelerating the creation and, perhaps the expansion, of high value, broad-based third party R&D collaborations that focus on specific gene families and other target clusters, while continuing to build, even accelerate, as previous guidance has indicated, a significant proprietary product pipeline. The combined company has an industry leading product pipeline and will continue to grow and advance the development of this pipeline. 4 Q: WHY DID YOU OPT TO ACQUIRE TECHNOLOGY RATHER THAN PRODUCT CANDIDATES? A: We have agreed to acquire Aurora because we saw the opportunity to add extremely complementary technology to our platform that will accelerate drug discovery and enable us to achieve our goal of having the capability of generating 2-3 NDA's on an annualized basis starting in the 2005-2010 timeframe. These NDAs will come through our partners' pipelines as well as through our own pipeline. With 12 product candidates in our pipeline and another 5 or more preclinical candidates anticipated this year, our product development engine has generated a pipeline capable of providing product candidates to the pharmaceutical industry now and into the future. Our objective is to develop cost-effectively the best and most productive drug discovery engine in the industry, which will position Vertex to execute its business strategy of bringing drugs to the market independently and with partners. We won't rule out acquiring a late-stage or marketed product that is complementary to our pipeline. We will continue to evaluate product acquisition opportunities, but remain conservative in our views toward shareholder dilution. Q: WHAT ARE YOUR GOALS FOR THE NEW COMPANY IN 2001? A: We cannot comment on the combined goals of the new company at this time. However, Vertex and Aurora are committed to achieving their existing milestones for 2001. These milestones are: VERTEX: o Expand chemogenomics into at least one additional gene family, o Name 5 or more new preclinical drug candidates, o Sign additional corporate alliances, o Acquire complementary capabilities, products and technologies, and o Continue to build our intellectual property estate. PRODUCT DEVELOPMENT MILESTONES o VX-175: complete phase III studies to support NDA filing in 2002 o VX-497: initiate HCV pivotal studies o VX-745: complete phase II RA study o VX-740: complete phase II RA study o Timcodar: complete phase II study o VX-148: complete phase I study AURORA: o Accelerate Aurora's target-focused drug discovery initiative (Big Biology(TM)). o Initiate and expand collaborative drug discovery programs. o Integrate new technologies and capabilities such as medicinal chemistry, NMR and X-ray crystallography. Q: WILL THE NEW COMPANY BE PROFITABLE IN 2001? A: Near-term profitability is not the driver of this deal. We remain committed to reaching profitability based on the commercialization of new products. As Vertex scanned the universe of platform technology companies with valuable assets that could be leveraged thoroughly into Vertex's chemogenomics capabilities, Aurora became particularly appealing. We do not anticipate our 2001 operating loss, before transaction-related costs, to materially increase as a result of this transaction. 5 Q: CAN YOU PROVIDE FINANCIAL GUIDANCE FOR 2001? A: On our first-quarter conference call on April 24, we stated that we expected our net loss for the full year of 2001 to be in the range of $60-$65 million. We do not expect the transaction, excluding merger-related expenses, to materially affect our projection for net operating loss in 2001. We cannot provide any further financial guidance at this time. Q: WHAT WILL THE PIPELINE OF THE COMBINED COMPANY LOOK LIKE? A: The combined company will have one product on the market and twelve products in clinical trials. The company's therapeutic targets include viral diseases, cancer, inflammatory and autoimmune diseases, and neurodegenerative diseases. With Aurora, Vertex will be positioned better to achieve our goal of having the capability of generating 2-3 NDA's on an annualized basis starting in the 2005-2010 timeframe. Generating this type of output means that Vertex would have to generate annualized input of approximately 3 phase IIIs, 6 phase IIs, 7 phase Is and 10 preclinical product candidates. Specifically, Vertex will be able to rapidly expand its focus in a much broader array of gene families and other target areas, such as GPCRs and ion channels, to discover new NCEs to feed the pipeline. Q: OVER WHAT TIMEFRAME WILL THIS MERGER ADD TO VERTEX'S PIPELINE? A: The most proximal benchmark in product creation relates to our Novartis kinase initiative. We believe that this transaction will accelerate the generation of proof-of-concept data in kinases, which should improve the speed to IND and knowledge behind our Novartis deliverables. In addition, we believe this transaction will accelerate our entry into new gene families and will also contribute to the formation of new corporate collaborations. Q: HOW MANY EMPLOYEES WILL THE NEW COMPANY HAVE? A: As of March 2001, Vertex had approximately 475 employees and Aurora had approximately 350 employees. So the combined company will have approximately 825 employees. Q: WHERE WILL THE NEW COMPANY BE HEADQUARTERED? A: The combined company's headquarters will be in Cambridge, MA. The company also will have offices in the U.K., San Diego, CA and Madison, WI. Q: WHAT IS THE COMBINED SQUARE FOOTAGE OF ALL THE VERTEX AND AURORA FACILITIES? A: The combined company has a total of just under 800,000 square feet of space. (This includes square footage for sites not built yet, i.e. Kendall Square.) 6 - -------------------------------------------------------------------------------- 3. Background on Aurora/Technology - -------------------------------------------------------------------------------- Q: I THOUGHT MOST OF AURORA'S EMPLOYEES WERE ENGINEERS, IS THAT TRUE? A: Less than half of Aurora's employees are engineers. The skills of the engineers could substantially impact several areas of our integrated drug discovery approach, specifically bioinformatics, computer modeling and high throughput screening. We were very attracted to this complementary scale up. The rest of the company's employees are primarily biology-based. To give you some background, Aurora was founded in 1995 to accelerate and enhance the discovery of new drugs using proprietary fluorescence assays, as well as compound screening technologies that integrated advances in robotics, instrumentation and miniaturization. Aurora's technology platform initially became the basis for a number of service and instrumentation agreements with a variety of pharmaceutical companies and research institutions. The subsequent development of Aurora's ultra high-throughput screening platform, together with a wide range of innovations in cell-based assay development and new fluorescent assay technologies, enabled the company to become an industry leader in cell biology and a research and development partner of choice to the pharmaceutical industry in the period 1996-2000. Q: DOES AURORA HAVE ANY DRUG DISCOVERY PROGRAMS OF THEIR OWN? A: Yes. Aurora has discovery programs in ion channels, GPCRs, enzymes and other classes of targets. Q: AURORA'S UHTSS SYSTEMS BUSINESS DOES NOT SEEM CORE TO VERTEX'S STATED OBJECTIVES. WHAT IS VERTEX'S PLAN WITH THIS BUSINESS? A: The systems business has been an integral component of Aurora's packaged systems, services and biology offering. The UHTSS systems business is the industry gold standard for assay screening and analysis. It has an encouraging business outlook and an ability to be further adapted to take advantage of a changing marketplace. Aurora management is committed to continue to build this business and plans to expand this business by offering second generation solutions. Vertex anticipates leveraging Aurora's hardware and software expertise to benefit existing protein science, bioinformatics and computer modeling techniques already in place. Since the company's founding, its focus has moved decisively toward discovery biology solutions rather than systems. Q: WHAT ARE CELL-BASED ASSAYS? HOW DO THEY SPEED THE DRUG DISCOVERY PROCESS? A: Cell based assays refer to technologies which use either normal or engineered cells to a) monitor a natural or engineered biological function; b) determine the effect of a drug or other molecule on such function; or c)help determine whether certain proteins are important targets of therapeutic intervention. 7 Q: MOLECULAR DEVICES ANNOUNCED A REVENUE SHORTFALL LAST WEEK. IS AURORA AT RISK FOR THE SAME TYPE OF REVENUE SHORTFALL? A: No. Aurora's primary business is the miniaturization of human biology. This is a different business model than that of Molecular Devices. Molecular Devices primary business is in plate readers, which are tools for the high throughput screening process. Molecular Devices attributes its revenue shortfall to a delay in orders for its lab equipment. The company blamed this delay on economic uncertainty, and first-quarter pressure from some of its customers. - -------------------------------------------------------------------------------- 4. Transaction Terms - -------------------------------------------------------------------------------- Q: WHAT ARE THE TERMS OF THE TRANSACTION? o Vertex will acquire Aurora in a stock-for-stock transaction. The fully-diluted equity value of the deal is approximately $592 million. Each share of Aurora will convert into shares of newly issued Vertex common stock at a fixed ratio of 0.62 shares of Vertex stock for each share of Aurora stock. Based on the closing price of Vertex stock of $39.25 on April 27, 2001, the fixed exchange ratio implies a price of $24.34 per Aurora share, a 44 percent premium to the closing price of $16.85 on April 27, 2001. Vertex expects to issue a total of approximately 14.0 million shares of common stock in exchange for Aurora's outstanding common stock, and Aurora options will be equitably converted to Vertex options. As of December 31, 2000, Aurora had approximately $100 million in net cash. On a pro forma (fully -diluted) basis, Aurora's shareholders will own approximately 18.5% of Vertex. Q: WHAT IS THE TOTAL VALUE OF THE TRANSACTION? A: The fully-diluted equity value is approximately $592 million Q: WHEN IS THE ACQUISITION EXPECTED TO BE COMPLETED? A: The acquisition is expected to be completed in the third quarter of 2001. Q: WHAT REGULATORY APPROVALS ARE NECESSARY TO COMPLETE THE TRANSACTION? A: The merger is subject to approval by both Vertex and Aurora shareholders and is subject to Hart-Scott-Rodino Antitrust Act approval and other closing conditions. Q: WHAT WILL BE THE ACCOUNTING TREATMENT OF THE TRANSACTION? A: We intend to account for the transaction as a pooling-of-interests. Q: WILL THERE BE A ONE-TIME CHARGE FOR ACQUISITION-RELATED COSTS? HOW MUCH? A: We anticipate recording one time charges associated with the transaction in 2001 that are customary for transactions of this magnitude, which should be in excess of $10 million. Q: HAVE BOTH COMPANIES COMPLETED DUE DILIGENCE? A: Yes. 8 Q: IS THERE A COLLAR ON THE TRANSACTION? A: There is no collar. This is a fixed exchange ratio transaction. Q: UNDER WHAT CIRCUMSTANCES CAN A PARTY TERMINATE? A: The merger agreement has customary deal protection measures which are quite technical in nature. Details of the merger agreement will be included in the Form 8-K that we expect to file with the SEC in the next few days. Q: IS THERE A BREAKUP FEE? A: Both parties are fully-committed to this transaction as is reflected in the breakup fee, which is $20 million. Additional details regarding the break-up fee will be made available in the Form 8-K that we expect to file in the next few days. Q: IS THE TRANSACTION DILUTIVE/ACCRETIVE? A: We anticipate this transaction will be accretive. We do not expect the transaction, excluding merger-related expenses, to materially affect our projection for net operating loss in 2001. We cannot provide any further financial guidance at this time. Q: HOW MANY SHARES OF VERTEX ARE CURRENTLY OUTSTANDING? A: Vertex has approximately 60,293,702 shares outstanding and approximately 11,480,085 options outstanding. Q: HOW MANY SHARES OF AURORA ARE CURRENTLY OUTSTANDING? A: Aurora has approximately 22,545,807 shares outstanding and approximately 4,690,942 options outstanding. Q: HOW MANY SHARES WILL VERTEX ISSUE IN CONNECTION WITH THE TRANSACTION? A: Vertex will issue approximately 14.0 million shares in connection with the transaction and Aurora options will be equitably converted into Vertex options. Q: WHO ARE THE COMPANIES' INVESTMENT BANKERS? A: Merrill Lynch is working with Vertex and Goldman Sachs is working with Aurora. Q: WHO ARE THE LEGAL ADVISORS FOR THE TRANSACTION? A: Mintz Levin is working with Vertex. Cooley Godward is working with Aurora. Q: WILL THE ACQUIRED COMPANY BE A WHOLLY OWNED SUBSIDIARY? A: Yes. Q: WILL THE ACQUIRED COMPANY OPERATE UNDER ITS OWN NAME? A: Yes. 9 Q: WHEN WILL YOU FILE A REGISTRATION STATEMENT? A: Vertex will file a registration statement in 3-4 weeks. Q: WHEN WILL THE COMPANIES MAIL THEIR PROXIES? A: We expect that proxies will be mailed in 6-10 weeks. Q: WHEN WILL THE SHAREHOLDER MEETING BE HELD? A: We expect that the shareholder meeting will be scheduled for late July 2001. Q: HAVE SENIOR EXECUTIVES AND BOARD OF DIRECTORS AT BOTH COMPANIES AGREED TO VOTE THEIR SHARES IN FAVOR OF THE DEAL? A: Yes. Q: WHO ARE THE ANALYSTS COVERING EACH OF THE COMPANIES? A: Vertex: o JP Morgan H&Q David Molowa o CS First Boston Meirav Chovav o Merrill Lynch Eric Hecht o Needham & Co. Carolyn Pratt o Prudential Vector Sec. Charles Duncan o Robertson Stephens Mike King o SG Cowen Bill Tanner Aurora: o Deutsche Banc Alex. Brown Jim Patricelli o JP Morgan Robert Olan o Robertson Stephens Mike King o Thomas Weisel Partners Scott Greenstone o UBS Warburg Jeannie Lorenz - -------------------------------------------------------------------------------- 5. Management Information - -------------------------------------------------------------------------------- Q: WHO WILL BE CEO, PRESIDENT, OTHER KEY EXECUTIVES? A: Joshua Boger will remain Chairman and CEO of Vertex Pharmaceuticals. Vicki Sato, Ph.D., will remain President of Vertex. Stuart Collinson, Aurora's Chairman, CEO and President, will serve on the transition team and will be a member of Vertex's Board of Directors. There will be no other changes to Vertex's Board of Directors. Harry Stylli, Ph.D., Aurora's Senior Vice President of Commercial Development, will become President of the Aurora subsidiary. 10 Q: ARE THERE ANY ADDITIONS/CHANGES TO MANAGEMENT THAT HAVE BEEN DETERMINED AT THIS TIME? A: We cannot comment on the roles of specific individuals until the transaction is completed. Q: WILL MANAGEMENT OF THE ACQUIRED COMPANY REMAIN FOLLOWING COMPLETION OF THE TRANSACTION? A: Aurora has a talented and experienced management team. It is our intention to retain this team. Q: HAVE THEY SIGNED EMPLOYMENT AGREEMENTS? A: Yes. - -------------------------------------------------------------------------------- 6. Employee Relations - -------------------------------------------------------------------------------- Q: WILL THERE BE ANY LAYOFFS? A: We do not envision any layoffs as a result of this transaction. Q: WILL ANYONE BE ASKED TO RELOCATE? A: No. We value San Diego and Madison as excellent recruiting beachheads. - -------------------------------------------------------------------------------- 7. General Information/Conference Call/Roadshow - -------------------------------------------------------------------------------- GENERAL INFORMATION: Q: WHAT ARE THE COMPANIES' TICKER SYMBOLS? A: Both companies are listed on NASDAQ. Vertex is VRTX. Aurora is ABSC. Q: HOW CAN I OBTAIN MORE INFO ON EITHER COMPANY? A: A good place to start is by visiting the companies' web sites. The address of Vertex is www.vrtx.com. The address of Aurora is www.aurorabio.com. Q: WHEN IS THE CONFERENCE CALL AND HOW DO I ACCESS IT? A: The companies will hold a joint conference call on April 30, 2001 at 9:00am ET. The call-in numbers are as follows: o US/Canada at 800-374-0296, and o International at 706-634-2394 o The call will also be webcast on Vertex's web site WWW.VRTX.COM. Q: WILL THERE BE A REPLAY OF THE CONFERENCE CALL? A: Yes. The replay will begin at 11:00 am ET. The call-in numbers for the replay are as follows: o US/Canada: 800-642-1687; o International: 706-645-9291. o The replay conference ID is 958173. Q: ARE EITHER OF THE COMPANIES DOING A POST-ANNOUNCEMENT ROAD SHOW? WHEN? WHERE? A: Yes, the companies are planning roadshows. You can contact the investor relations department at each company to find out about the schedule. 11 ************************** Investors and security holders are advised to read the joint proxy statement/prospectus regarding the proposed merger when it becomes available, because it will contain important information. Such joint proxy statement/prospectus will be filed with the Securities and Exchange Commission by Vertex and Aurora. Investors and security holders may obtain a free copy of the joint proxy statement/prospectus (when available) and other documents filed by Vertex and Aurora at the Securities and Exchange Commission's web site at www.sec.gov. The joint proxy statement/prospectus and such other documents may also be obtained from Vertex by directing such request to Vertex Pharmaceuticals, 130 Waverly Street, Cambridge, MA 02139, Attn: Investor Relations, tel: (617) 577-6000; e-mail: InvestorInfo@vpharm.com. The joint proxy statement/prospectus and such other documents may also be obtained from Aurora by directing such request to Aurora Biosciences, 11010 Torreyana Road, San Diego, CA 92121, Attn: Investor Relations, tel: 858-404-6600; e-mail: ir@aurorabio.com. **************************