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SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 10-K

[X] ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
ACT OF 1934 for the fiscal year ended: December 31, 1999
----------------

[ ] TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
EXCHANGE ACT OF 1934 for the transition period from __________to _________.

Commission File Number: 0-19290

COR THERAPEUTICS, INC.
(Exact name of Registrant as specified in its charter)

DELAWARE
(State or other jurisdiction of incorporation or organization)
94-3060271
(I.R.S. employer identification no.)
(650) 244-6800
(Registrant's telephone number, including area code)
256 EAST GRAND AVENUE, SOUTH SAN FRANCISCO, CALIFORNIA 94080
(Address of principal executive offices and zip code)

Securities registered pursuant to Section 12(b) of the Act: None

Securities registered pursuant to Section 12(g) of the Act: Common Stock, $.0001
Par Value Preferred Share Purchase Rights

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. Yes [X] No [ ]

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. [X]

As of March 1, 2000, the aggregate market value (based upon the closing sales
price of such stock as reported in The Nasdaq Stock Market(R) on such date) of
the voting stock held by non-affiliates of the Registrant was $2,006,187,000.
(Excludes 4,807,187 shares outstanding at March 1, 2000 of the Registrant's
Common Stock held by directors, executive officers and holders of more than 5%
of the Company's Common Stock. Exclusion of shares held by any person should not
be construed to indicate that such person possesses the power, direct or
indirect, to direct or cause the direction of the management or policies of the
Registrant, or that such person is controlled by or under common control with
the Registrant.)

As of March 1, 2000, the number of outstanding shares of the Registrants' Common
Stock was 26,285,267.

DOCUMENTS INCORPORATED BY REFERENCE:

Reference Document Form 10-K
- --------- -------- ---------

(1) Portions of the Registrant's definitive proxy statement Part III
with respect to the Registrant's 2000 Annual Meeting of
Stockholders, to be filed with the Securities and
Exchange Commission not later than 120 days after the
close of the Registrant's fiscal year.

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PART I

ITEM 1. BUSINESS

Except for the historical information contained in this Report, the following
discussion contains forward-looking statements that involve risks and
uncertainties. Our actual results could differ materially from those discussed
herein. Factors that could cause or contribute to such differences include, but
are not limited to, those discussed below and in the sections entitled
"Additional Risk Factors" and "Management's Discussion and Analysis of Financial
Condition and Results of Operations." INTEGRILIN(R) (eptifibatide) Injection,
COR Therapeutics(R), and COR(R) are registered trademarks of COR Therapeutics,
Inc.

GENERAL

COR Therapeutics, Inc. was incorporated in Delaware on February 4, 1988. COR
Therapeutics, Inc. is sometimes referred to in this Report as COR, COR
Therapeutics, we or us. We are dedicated to the discovery, development and
commercialization of novel pharmaceutical products to establish new standards of
care for the treatment and prevention of severe cardiovascular diseases. Our
complementary research and development programs seek to address critical needs
in cardiovascular diseases, including unstable angina, acute myocardial
infarction, venous thrombosis and restenosis. In addition to INTEGRILIN, we have
developed a portfolio of cardiovascular product candidates and programs by
combining our expertise with advanced drug discovery techniques.

INTEGRILIN is the first product that COR has taken from discovery to
commercialization. Approved by the U.S. Food and Drug Administration ("FDA") in
May 1998, INTEGRILIN is indicated for the treatment of patients with an acute
coronary syndrome and patients who undergo angioplasty procedures. The acute
coronary syndrome indication includes patients with unstable angina and
non-Q-wave myocardial infarction, whether they receive medical treatment or
undergo angioplasty.

Schering-Plough Ltd. and Schering Corporation are our worldwide partners for
INTEGRILIN. Sometimes we refer to Schering-Plough Ltd. and Schering Corporation
in this Report as Schering. COR and Schering co-promote INTEGRILIN in the United
States and share any profits or losses. Outside of the United States, Schering
markets INTEGRILIN as our exclusive licensee on a royalty-bearing basis.

With Schering, we have conducted or are conducting Phase II clinical trials of
INTEGRILIN with different fibrinolytics in the setting of acute myocardial
infarction. Along with Schering, we also sponsor additional clinical trials of
INTEGRILIN in a variety of clinical settings.

In addition to our commercial activities, we continue to pursue a wide array of
research and development programs. Our next potential product is an oral
glycoprotein IIb-IIIa inhibitor to prevent platelet aggregation. Sometimes we
refer to glycoprotein IIb-IIIa as GP IIb-IIIa in this Report. We are also
conducting preclinical research and development in several other cardiovascular
programs.

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STRATEGY

- - Maximize the Revenue Potential of INTEGRILIN(R) (eptifibatide) Injection. We
are focused on growing sales of INTEGRILIN, which is the only drug approved
for use in both acute coronary syndromes and angioplasty procedures. Our
goal is for INTEGRILIN to be standard therapy for acute cardiovascular
disease. Accordingly, we are educating the medical community to use
INTEGRILIN early in the treatment process. We are also pursuing approvals
for additional indications of the drug.

- - Focus on Cardiovascular Disease. We believe that by combining our clinical
expertise, extensive knowledge of the molecular and cellular biology of
cardiovascular disease and advanced drug discovery techniques, we can
continue to develop new therapeutics to address large, unmet market
opportunities for both chronic and acute cardiovascular diseases. Our
research and development efforts are focused on developing and
commercializing drugs that meet these needs. We focus our marketing and
sales efforts on health care providers that treat cardiovascular disease.

- - Continue to Build Relationships with Leading Physicians and Scientists. We
conduct clinical trials at premier academic and clinical centers under the
supervision of many of the world's leading cardiologists. We build strong
relationships with prominent scientists and clinical cardiologists by
sponsoring and conducting research and providing for increased exposure of
our product and product candidates in the medical community through clinical
and research publications and educational initiatives, including seminars
and conferences.

- - Maximize Value of Strategic Relationships. We develop relationships and
strategic collaborations with pharmaceutical and biotechnology companies.
Our goal is to work with companies who can enhance our scientific expertise
and technology, sales and marketing capabilities and financial position.

THERAPEUTIC OPPORTUNITIES IN CARDIOVASCULAR DISEASE

Despite decades of extensive research and development and significant advances
in its treatment, cardiovascular disease remains the leading cause of death in
the United States. Approximately one million people die each year from heart
attacks, strokes and related diseases. As the number of elderly people in the
population increases, the number of deaths attributable to these diseases
continues to climb. We focus our research and development efforts on agents that
have the potential to prevent and/or treat these diseases. Our complementary
research and development programs seek to address critical needs in
cardiovascular diseases, including unstable angina, acute myocardial infarction,
venous thrombosis and restenosis.

In arterial thrombosis, an aggregation of platelets (a thrombus, essentially a
plug) forms on the lining of an injured artery. The thrombus occludes the artery
and thereby impairs its ability to supply oxygen to the heart, brain and other
organs. In the heart, disorders from arterial thrombosis range from prolonged
episodes of severe chest pain (including unstable angina) to heart attack (acute
myocardial infarction) to sudden death. In the brain, disorders range from a
temporary reduction in oxygen supply (transient ischemic attacks) to stroke.
Each year, approximately six million people suffer from severe chest pain, one
million from heart attack and 600,000 from stroke.

In venous thrombosis, disorders are generally related to a thrombus breaking off
from the lining of an injured artery or vein. The thrombus may travel to the
lungs and cause a pulmonary embolism, a serious disorder in which blood supply
is blocked and lung tissue is killed. Each year, over 270,000 patients are
diagnosed with venous thrombosis. Approximately 50,000 patients die annually
from pulmonary embolisms.

In restenosis, an artery significantly re-narrows following an angioplasty
procedure, usually within six months. Approximately 500,000 patients undergo
angioplasties each year and up to 40% suffer from restenosis. New treatments or
devices such as stents help reduce restenosis in angioplasty. However, stenting
itself can be complicated by restenosis, particularly in smaller vessels.
Restenosis therefore remains a threat whether or not stents are used.

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INTEGRILIN(R) (EPTIFIBATIDE) INJECTION

INTEGRILIN is a small synthetic peptide that blocks the platelet receptor GP
IIb-IIIa to inhibit platelet aggregation. By blocking GP IIb-IIIa, INTEGRILIN
helps prevent thrombus formations from fully occluding coronary arteries, a
situation that can lead to heart attack or death in patients with acute coronary
syndromes or patients undergoing percutaneous coronary intervention.
Importantly, the effects of INTEGRILIN are specific to platelets, thereby
avoiding interference with other normal cardiovascular processes. Additionally,
certain effects of INTEGRILIN can be reversed once therapy with INTEGRILIN is
discontinued. Well over one million people in the United States annually are
candidates for INTEGRILIN therapy.

INTEGRILIN has the broadest range of indications among GP IIb-IIIa inhibitors
approved for marketing in the United States. INTEGRILIN can be administered at
the time of diagnosis in the emergency department to patients with acute
coronary syndromes regardless of whether they are medically managed or
ultimately undergo percutaneous coronary intervention on INTEGRILIN therapy.
INTEGRILIN can be administered to patients prior to (but not during) coronary
artery bypass grafting surgery. Additionally, INTEGRILIN can also be
administered at the time of percutaneous coronary intervention to patients who
undergo elective, emergency or urgent percutaneous coronary intervention.

Contraindications include, but are not limited to, a history of bleeding
diathesis or stroke, evidence of abnormal bleeding within the previous 30 days,
recent major surgery or concomitant use of another parenteral GP IIb-IIIa
inhibitor. Bleeding is the most common complication encountered during
INTEGRILIN therapy. The majority of excess major-bleeding events were localized
at the femoral artery access site. Oropharyngeal, genitourinary,
gastrointestinal and retroperitoneal bleeding were seen more commonly with
INTEGRILIN compared with placebo.

A competing product, abciximab, is used primarily in the catheterization
laboratory setting in patients undergoing percutaneous coronary intervention.
Another competing product, tirofiban, is used primarily in the setting of acute
coronary syndromes. See "Competition."

INTEGRILIN was studied in two randomized, double-blind, placebo-controlled Phase
III clinical trials: the PURSUIT trial and the IMPACT II trial. PURSUIT was the
largest clinical study ever conducted of patients with unstable angina and
non-Q-wave myocardial infarction and the largest study ever conducted with a GP
IIb-IIIa inhibitor. PURSUIT's results were published in August 1998 in The New
England Journal of Medicine.

The ESPRIT study of INTEGRILIN was a randomized, double-blind,
placebo-controlled trial, originally planned for 2,400 patients undergoing
non-urgent percutaneous coronary intervention involving placement of a stent. In
March 2000, we and Schering announced that INTEGRILIN significantly reduced the
combined incidence of death, heart attack, need for urgent repeat intervention,
or the need for thrombotic bail-out therapy from 10.5 percent with placebo to
6.6 percent (P = 0.0015) over the 48 hours following non-urgent balloon
angioplasty combined with intracoronary stenting. This was the primary endpoint
of the ESPRIT study. In February 2000, an independent Data Safety Monitoring
Committee determined that enrollment in the study should be stopped early in the
ESPRIT study after an interim analysis of 1,758 patients revealed a highly
statistically significant reduction in death or heart attack combined at 48
hours with INTEGRILIN relative to placebo. Additional results of the ESPRIT
study of INTEGRILIN were presented in March 2000 at the 49th Scientific Sessions
of the American College of Cardiology in Anaheim, California.

Our marketing strategy for INTEGRILIN is to encourage early use of INTEGRILIN in
patients with acute coronary syndromes and in patients undergoing percutaneous
coronary intervention. We believe that INTEGRILIN sales will continue to
increase as early usage becomes more common and as the number of hospitals
stocking INTEGRILIN increases.

With Schering, we have each established cardiovascular sales forces to educate
the medical community about GP IIb-IIIa therapy and to market the use of
INTEGRILIN in such therapy. We focus our selling efforts for INTEGRILIN on
clinical cardiologists, interventional cardiologists and emergency medicine
physicians. We also focus on hospital pharmacy directors, formulary committee
members, hospital administrators and nurses, all of whom might affect purchasing
decisions.

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With Schering, we are conducting or have conducted Phase II clinical trials of
INTEGRILIN(R) (eptifibatide) Injection with different fibrinolytics in the
setting of acute myocardial infarction. Along with Schering, we also sponsor
additional clinical trials of INTEGRILIN in a variety of clinical settings.

RESEARCH AND DEVELOPMENT PROGRAMS

Pipeline

The following table summarizes information about our primary research and
development programs. For further information, see the more detailed
descriptions of these programs elsewhere in this Report.

Potential Product/Program Indication Status
- --------------------------------------- -------------------------------- ------------------------

Oral GP IIb-IIIa Inhibitor (cromafiban) Acute coronary syndromes, stroke Phase II clinical trials
Factor Xa inhibitor Venous and arterial thrombosis, Preclinical
atrial fibrillation
Growth factor inhibitor Restenosis, cancer, Preclinical
fibroinflammatory disease
Platelet ADP receptor Acute coronary syndromes, Research
restenosis, stroke prevention
Myocardial signal transduction Congestive heart failure Research
Integrin signal transduction Thrombosis, inflammation, Research
atherosclerosis, tumor
metastasis
Non-cardiovascular programs Inflammatory and autoimmune Research
diseases, certain malignancies

Oral GP IIb-IIIa Inhibitor Product Candidate

Current therapies aimed at preventing arterial thrombosis either do not address
the underlying cause of thrombosis (namely, platelet aggregation) and/or are
severely limited in their ability to fight thrombosis. Agents such as beta
blockers, calcium antagonists, warfarin sodium and nitrates all inhibit platelet
aggregation, but through secondary processes and only under the careful
supervision of a monitoring physician. On the other hand, agents such as
aspirin, ticlopidine and clopidogrel do not require much supervision, but are
relatively weak inhibitors of platelet aggregation. Since the platelet receptor
GP IIb-IIIa acts as the final common pathway for platelet aggregation, we
believe that its inhibition offers the most effective means to prevent
thrombosis.

Oral GP IIb-IIIa inhibitors could represent a new class of drugs for patients
with a history of acute coronary syndromes or cerebrovascular accidents. Over
six million people in the United States have a history of heart attack, stroke
or transient ischemic attack. Oral GP IIb-IIIa inhibitors may prove useful in
helping to prevent these catastrophic events.

We have developed an oral GP IIb-IIIa inhibitor, called cromafiban, to prevent
platelet aggregation. Results to date of Phase I and initial Phase II studies
for cromafiban show that it has high affinity and specificity for GP IIb-IIIa.
Inhibition of platelet aggregation by cromafiban has been shown to be dose- and
concentration-dependent. Plasma concentrations have indicated a sufficiently
long elimination half-life to allow for once-daily dosing with a low
peak-to-trough ratio. No food interactions have been observed. Minor bleeding
has been the most prevalent complication encountered during cromafiban therapy
in clinical trials.

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Factor Xa Inhibitor Program

We have identified the factor Xa/prothrombinase complex as a target for small
molecule inhibitors. The factor Xa/prothrombinase complex catalyzes the
conversion of prothrombin to thrombin. We believe that the inhibition of this
conversion offers the possibility for a safer and potentially more efficacious
approach to arterial and venous thrombosis than is presently available with
agents that inhibit both thrombin generation and thrombin activity (e.g.,
heparin and low molecular weight heparin). Our scientists have discovered
multiple chemical classes of novel small molecule factor Xa inhibitors with high
potency and specificity that have been shown to block both arterial and venous
thrombosis in various animal models. We are currently conducting preclinical
studies of lead compounds that can be administered orally. We believe that the
development of inhibitors in this class may offer significant clinical
advantages over presently available agents such as heparin, low molecular weight
heparin or warfarin sodium.

Growth Factor Inhibitor Program

Our growth factor inhibitor program is directed toward the discovery of protein
and small molecule inhibitors of certain growth factor receptors in the tyrosine
kinase family. These inhibitors have the potential to reduce restenosis
following coronary intervention. Certain cancers may also depend upon platelet
derived growth factor for growth. Therefore, growth factor receptor inhibition
may also have therapeutic potential in these cancers. We have been pursuing this
program in collaboration with Kyowa Hakko Kogyo Co., Ltd. In November 1999 the
research term of this collaboration expired in accordance with the terms of our
agreement with Kyowa Hakko. COR plans to continue this research program. See
"Collaboration Agreements -- Collaboration Agreement with Kyowa Hakko Kogyo Co.,
Ltd."

Platelet ADP Receptor Program

Our platelet ADP receptor program is directed toward the discovery of agents for
the treatment of arterial thrombosis as well as stroke. ADP receptors on the
surface of platelets play a key role in promoting platelet activation and
aggregation. We have identified competitive antagonists that we believe will be
better than presently available agents, such as ticlopidine and clopidogrel.

Myocardial Signal Transduction Program

Our myocardial signal transduction program is directed toward the discovery of
agents for the treatment and prevention of congestive heart failure. We focus
our efforts on particular molecular targets in a specific signaling pathway as a
site for intervention. This program may also have application in the treatment
of myocardial ischemia.

Integrin Signal Transduction Program

Our integrin signal transduction program is directed toward the discovery of
agents that are useful for the treatment or prevention of a wide variety of
disorders including thrombosis, inflammation, atherosclerosis and tumor
metastasis. Integrins play a key role in modulating not only cell migration and
shape but also growth and differentiation. We are conducting this effort in
collaboration with investigators at the Scripps Research Foundation.

Non-cardiovascular Research Applications

Our research has resulted in the identification of compounds with potential
non-cardiovascular applications. We believe certain of our growth factor
inhibitors may have applications in treating certain other disorders that
involve cell proliferation, such as cancer, angiogenesis and chronic renal
failure. We have identified other compounds with potential applications in the
areas of wound healing, tumor metastasis and osteoporosis. We intend to pursue
such opportunities and seek collaboration partners to develop and commercialize
any potential product opportunities where appropriate.

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DRUG DISCOVERY AND DEVELOPMENT CAPABILITIES

To achieve our drug discovery and development objectives, we have established
advanced capabilities in several key technology areas.

Cardiovascular Biology

Our scientists and advisors have contributed to certain key advances in the
scientific understanding of thrombosis, restenosis and heart failure. We have
applied their expertise in our choice of specific disease targets and in the
creation of our drug discovery strategies. Our major focus has been on
thrombosis, the process underlying the syndromes of acute myocardial infarction,
unstable angina and restenosis, as well as the process of vascular smooth muscle
cell proliferation following percutaneous coronary intervention or other
vascular interventional procedures. Our scientists have targeted several of the
potential mechanisms that regulate intravascular thrombosis or restenosis,
including the platelet, the coagulation factor cascade and the vascular wall.
Our approach has been to understand the pathophysiology of the disease process
itself and then to identify and characterize molecular targets for which a
potential product might have a positive therapeutic impact.

High-Throughput Screening

We have applied our biological expertise to develop a variety of novel assays
suitable for high-throughput screening. For each high-throughput screening
assay, we have also developed numerous secondary assays for confirming in vitro
activity and specificity. Our screening library consists of compounds either
developed internally or purchased from commercial or academic groups. We use
computer-based algorithms to model molecular diversity in order to maximize the
overall diversity of our compound library. We are currently conducting
high-throughput screening using multiple proprietary assays against our
molecular targets.

Medicinal Chemistry

We have established capabilities to synthesize small organic molecules. These
capabilities use both structure-based design principles and traditional analog
synthetic approaches applied to small molecules discovered through the screening
of organic molecules in our proprietary assays. We also have a combinatorial
chemistry program. Using structure-based design approaches, we believe we have
developed particular expertise in developing small molecule organic compounds
that mimic the activity of peptide leads. This capability enables us to more
effectively generate compounds with appropriate pharmaceutical properties, such
as oral bioavailability and a prolonged half-life.

Functional Genomics

Our functional genomics program is directed toward the discovery and validation
of novel targets in vascular diseases. These efforts include genomic approaches
aimed at identifying novel genes expressed in platelets and cells of the
vascular wall that are playing critical roles in the pathogenesis of
cardiovascular disease. These efforts are being carried out in collaboration
with outside researchers.

Animal Model Studies

We have established an important internal capability in the development of
animal models. We use a variety of animal models that are relevant in predicting
responses to our disease targets in humans, including proprietary models
developed internally. In addition, we work closely with outside consultants and
laboratories in other areas, such as the development of knock-out and transgenic
models and the evaluation of compounds in primate models. Using internal and
external capabilities, we can rapidly evaluate compounds with therapeutic
potential in multiple complementary models.

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Product Development Capabilities

We have established product development capabilities in analytical development,
drug metabolism and pharmacokinetics, which allow us to evaluate the
pharmaceutical properties of compounds with therapeutic potential. We also have
established formulation development capabilities in collaboration with outside
consultants and contract manufacturers. Our capabilities extend to
pharmacokinetic analysis for ongoing clinical trials for INTEGRILIN(R)
(eptifibatide) Injection and other products and product candidates.

RESEARCH AND DEVELOPMENT EXPENSES

In 1999, 1998 and 1997, our research and development expenses were $36,563,000,
$39,915,000, and $47,831,000 respectively. For further information about our
research and development expenses, see "Management's Discussion and Analysis of
Financial Condition and Results of Operations."

MARKETING AND SALES STRATEGY

Our overall marketing strategy is to market any products for which we obtain
approval either directly or through co-promotion arrangements or other licensing
arrangements with pharmaceutical or biotechnology companies. We target products
under development toward both the acute care and the chronic care markets. We
intend to retain selected North American and international marketing rights for
products, where appropriate.

We have not developed a specific commercialization plan with respect to our
potential products. Implementation will depend in large part on the market
potential of any product candidates, as well as on our financial resources. We
may establish co-promotion, corporate partner or other arrangements for the
marketing and sale of certain products and in certain geographic markets. We may
not be successful in establishing such arrangements and/or these arrangements
may not result in the successful marketing and sales of any of our products or
product candidates.

Sales of INTEGRILIN and potential products may depend heavily upon the
availability of reimbursement from third-party payers, such as government and
private insurance plans. We meet with administrators of these plans to discuss
the potential medical benefits and cost-effectiveness of our products. We
believe this approach may assist in obtaining reimbursement authorization for
our products from these third-party payers. See "Additional Risk Factors."

COMPETITION

Due to the incidence and severity of cardiovascular diseases, the market for
therapeutic products that address such diseases is large, and competition is
intense and expected to increase. Our most significant competitors are major
pharmaceutical companies and established biotechnology companies, which have
significant resources and expertise in research and development, manufacturing,
testing, obtaining regulatory approvals and marketing. Emerging pharmaceutical
and biotechnology companies may also prove to be significant competitors,
particularly through collaboration arrangements with large pharmaceutical
companies. Many of these competitors have cardiovascular products approved or in
development and operate large, well-funded cardiovascular research and
development programs. Furthermore, academic institutions, governmental agencies
and other public and private research organizations conduct research, seek
patent protection and establish collaboration arrangements for product and
clinical development and marketing in the cardiovascular disease field and other
areas being targeted by us. In addition, these companies and institutions
compete with us in recruiting and retaining highly qualified scientific, sales,
and management personnel.

We are aware of products in research or development by our competitors that
address all of the diseases and disorders being targeted by us. Any of these
products may compete with potential products being developed by us, depending
upon the pharmacological characteristics of each product. Competition is based
primarily on product

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efficacy, safety, timing and scope of regulatory approvals, availability of
supply, marketing and sales capability, reimbursement coverage, price and patent
position.

In particular, some of our competitors have programs specifically designed to
develop both parenteral and oral GP IIb-IIIa inhibitors. Two other parenteral GP
IIb-IIIa inhibitors have received regulatory approval in the United States and
Europe and are currently being marketed and sold: abciximab, which is being
developed by Johnson & Johnson and marketed by Johnson & Johnson and Eli Lilly &
Co.; and tirofiban, which is being developed and marketed by Merck & Co., Inc.
Pharmaceutical companies are also developing orally available GP IIb-IIIa
inhibitors with agents at various stages of development. We believe these orally
administered compounds are not likely to represent direct competition for
parenteral products because they are being designed for chronic therapies, are
expected to be dosed to have a lesser anti-platelet effect than parenteral
products and are designed to have a long biological half-life. Competitors might
succeed in developing products or technologies that are more effective than
those being developed by us. These products or technologies might render our
technology obsolete or noncompetitive.

Any product which we succeed in developing and for which we gain regulatory
approval must then compete for market acceptance and market share. For certain
of our potential products, important competitive factors will be the pricing and
timing of market introduction of competitive products. Accordingly, important
competitive factors will be the relative speed with which companies can develop
products, complete the clinical testing and approval processes and supply
commercial quantities of the product to the market. With respect to clinical
testing, competition may also delay progress by limiting the number of clinical
investigators and patients available to test our potential products.

COLLABORATION AGREEMENTS

We evaluate, on an ongoing basis, potential collaborations where such
relationships may complement and expand our research, development, sales or
marketing capabilities. We are currently engaged in a number of collaborations
with other companies, consultants, universities and medical centers.

Collaboration Agreement with Schering-Plough Ltd. and Schering Corporation

In April 1995, we entered into a collaboration agreement with Schering to
jointly develop and commercialize INTEGRILIN(R) (eptifibatide) Injection on a
worldwide basis. In December 1998 and November 1999, we amended our agreement
with Schering. The November 1999 amendment extended the period in which Schering
has exclusive rights to market INTEGRILIN in Europe, added a period of marketing
exclusivity for Schering in Canada, and increased the royalty opportunities
payable to us during the period of Schering's exclusivity. Under this agreement,
decisions regarding the ongoing development and marketing of INTEGRILIN are
generally subject to the oversight of a joint steering committee with equal
membership from Schering and ourselves, although certain development decisions
are allocated specifically to us and in those markets where Schering has
exclusive marketing rights, Schering has decision-making authority with respect
to marketing issues.

With Schering, we co-promote INTEGRILIN in the United States and share any
profits or losses. Schering is responsible for the distribution of the final
product from manufacturers to wholesalers. Outside of the United States,
Schering markets INTEGRILIN as our exclusive licensee on a royalty-bearing
basis. We have the right in the future to co-promote the product in Europe and
Canada and share any profits or losses. In the United States, the exact
profit-sharing ratio between the companies depends on the amount of sales effort
contributed by each company. Schering participates in and shares the costs of
continuing development of INTEGRILIN. Under the terms of the agreement, both
Schering and we have certain rights to terminate for breach.

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We recognized the following revenues under our agreements with Schering in 1999,
1998 and 1997 (in thousands):

1999 1998 1997
------- ------- -------

Copromotion revenue $34,132 $ 3,933 $ --
Milestone revenue 12,000 32,000 8,000
Development and other contract revenue 10,526 5,730 11,290
------- ------- -------
$56,658 $41,663 $19,290
======= ======= =======

Schering has agreed to pay additional milestones to us if specified development
milestones are achieved. If Schering were to breach or terminate its agreement
with us, fail to pay its share of collaborative costs, or otherwise fail to
conduct its collaborative activities in a timely manner, we would be required to
devote substantial additional resources to the continued development and
promotion of INTEGRILIN(R) (eptifibatide) Injection or seek to obtain
capabilities or funding through alternative sources, which would result in a
significant delay of these activities.

Collaboration Agreement with Kyowa Hakko Kogyo Co., Ltd.

In November 1992, we entered into a collaboration agreement with Kyowa Hakko
Kogyo Co., Ltd. focused on the discovery and development of small molecule
pharmaceuticals, primarily for the prevention of restenosis following
angioplasty. The research term of our collaboration expired in November 1999 in
accordance with the terms of that agreement. COR plans to continue this research
program. We and Kyowa Hakko both have specific development and marketing rights
for any products resulting from the collaboration. In addition, under the terms
of the agreement, Kyowa Hakko has certain rights to supply bulk material for the
manufacture of any products resulting from the collaboration, and we have agreed
to purchase our requirements for such material from Kyowa Hakko.

MANUFACTURING AND PROCESS DEVELOPMENT

We have no manufacturing facilities for either the commercial production of bulk
active drug substances or the manufacture of final dosage forms. We are
dependent on contract manufacturers or collaboration partners for the commercial
production of INTEGRILIN and the production of any potential products or
compounds for preclinical research and clinical trial purposes, and we expect to
be dependent on such manufacturers or collaboration partners for the foreseeable
future. We have conducted manufacturing testing programs required to obtain FDA
and other regulatory approvals for the manufacture of drug substances and drug
products. However, we have no experience manufacturing pharmaceutical or other
commercial products.

We believe our contracted supply of INTEGRILIN is sufficient to meet current
market demand. We work with our vendors on capacity forecasts to assure that
there is an adequate supply of the drug, including raw materials, in the future.
We have established supply arrangements with two suppliers for the bulk product.
We have established long-term supply arrangements with another two suppliers for
the filling and final packaging of INTEGRILIN. Our manufacturing plans include
the addition of capacity with our existing suppliers however, we may need
expanded capacity to meet additional market demand. If this were to occur, we
may not be able to expand capacity in a timely manner or at all.

Our dependence upon third parties for the manufacture of our potential products
may adversely affect our profit margins, if any, and our ability to develop and
manufacture products on a timely and competitive basis. In connection with the
commercialization of our existing and potential products, our strategy is to
establish multiple third-party manufacturing sources on commercially reasonable
terms. We may not be able to establish such sources on commercially reasonable
terms. Even if such sources are established, they may not continue to be
available to us on commercially reasonable terms. In the event that we are
unable to obtain contract manufacturing or obtain such manufacturing on
commercially acceptable terms, we may not be able to commercialize our products
as planned.

We believe that material that has been produced by contract manufacturers has
been done in conformity with applicable regulatory requirements. We have
established a quality assurance/control program to ensure that our compounds are
manufactured in accordance with Current Good Manufacturing Practices, the
requirements of the California State Food and Drug Administration and other
applicable regulations. Any contract manufacturers that we may use must adhere
to Current Good Manufacturing Practices. The FDA or other regulatory agencies
may not

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approve the processes or the facilities that may be used for the manufacture of
any of our potential products. In addition, if the facilities cannot pass
regular post-approval FDA inspections, manufacturing and distribution may be
disrupted, recalls of distributed products may be necessary and other sanctions
could be applied, which would have a material adverse affect on our business,
financial condition and results of operations. See "Government Regulation."

We believe that all of our existing compounds can be produced using established
manufacturing methods, including cell culture, fermentation or traditional
pharmaceutical synthesis. The manufacture of our compounds is based in part on
technology that we believe to be proprietary. Contract manufacturers may utilize
their own technology, our technology or that of third parties. Successful
technology transfer is needed to ensure success with potential secondary
suppliers. Such manufacturers may not abide by the limitations or
confidentiality restrictions in licenses with us. In addition, any such
manufacturer may develop process technology related to the manufacture of our
compounds that such supplier owns either independently or jointly with us. This
would increase our reliance on such manufacturer or require us to obtain a
license from such manufacturer in order to have our products manufactured. Any
such license may not be available on terms acceptable to us, if at all.

For our product candidates in development, we expect that we will need to
improve or modify our existing process technologies and manufacturing
capabilities. We cannot quantify the time or expense that may ultimately be
required to improve or modify our existing process technologies, but it is
possible that such time or expense could be substantial. Moreover, we may not be
able to implement any of these improvements or modifications successfully.

PATENTS, PROPRIETARY RIGHTS AND LICENSES

Patents

Our policy is to file patent applications to protect technology, inventions and
improvements that are important to the development of our business. We also rely
upon trade secrets, know-how, continuing technological innovations and licensing
opportunities to develop and maintain our competitive position. We plan to
prosecute and defend our patent applications aggressively, including any patents
that may issue, as well as our proprietary technology.

Our success will depend in part on our ability to obtain and maintain patent
protection for our product, INTEGRILIN(R) (eptifibatide) Injection, and our
product candidates in development, both in the United States and in other
countries. We have patents or have filed applications for patents covering many
of our product candidates, processes, various aspects of our platelet
aggregation inhibitor, growth factor receptor and venous thrombosis programs, as
well as other programs. Many of the patents or applications include composition
of matter claims relating to a number of our compounds. Also, we have
exclusively licensed a number of related patent applications with respect to
certain of our product candidates. The patent positions of pharmaceutical and
biotechnology firms, including ourselves, are often uncertain and involve
complex legal and factual questions. In addition, the coverage claimed in a
patent application can be significantly reduced before the patent is issued.
Consequently, we do not know whether any of our applications will result in the
issuance of patents or whether any of our issued patents will provide
significant proprietary protection or will be circumvented or invalidated. Since
patent applications in the United States are maintained in secrecy until patents
issue and since publication of discoveries in the scientific or patent
literature often lags behind actual discoveries, we cannot be certain that we
were the first creator of inventions covered by our pending patent applications
or that we were the first to file patent applications for such inventions.
Moreover, we may need to participate in interference proceedings declared by the
U.S. Patent and Trademark Office or, with respect to foreign patents and patent
applications, other proceedings to determine priority of invention, which could
result in substantial cost to us, even if the eventual outcome is favorable to
us.

The development of therapeutic products for cardiovascular applications is
intensely competitive. A number of pharmaceutical companies, biotechnology
companies, universities and research institutions have filed patent applications
or received patents in this field. Some of these applications are competitive
with our applications or conflict in certain respects with claims made under
applications that cover one or more of our programs. Such conflict could result
in a significant reduction of the coverage of our patents, if issued, which
could materially adversely affect our prospects. In addition, if patents are
issued to other companies that contain competitive or

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conflicting claims and such claims are ultimately determined to be valid, we may
not be able to obtain licenses to these patents at a reasonable cost or develop
or obtain alternative technology.

In October 1997, a patent opposition was filed in Europe by another company
against the claims of a patent granted to us in Europe covering broad, generic
claims for INTEGRILIN(R) (eptifibatide) Injection, as well as numerous related
compounds that are not part of our core technology. The opposition asserts that
all claims of the patent are unpatentable. We intend to continue to vigorously
defend our patent. However, this patent opposition may result in an unfavorable
outcome.

Trade Secrets

We rely upon trade secret protection for our confidential and proprietary
information. Other parties may independently develop substantially equivalent
proprietary information and techniques, otherwise gain access to our trade
secrets or disclose our trade secrets or such substantially equivalent
technology. In addition, we may not be able to meaningfully protect our trade
secrets.

Licensed Technology

We have obtained licenses from certain universities, companies and research
institutions to technologies, processes and compounds that we believe may be
important to the development of our products. These agreements require us to pay
license maintenance fees and, upon commercial introduction of certain products,
to pay royalties. These include exclusive license agreements with the Regents of
the University of California that may be cancelled or converted to non-exclusive
licenses if specified milestones are not achieved. These licenses may not
provide effective protection against our competitors.

Confidentiality Agreements

We require our employees, consultants, outside scientific collaborators,
sponsored researchers and other advisors to execute confidentiality agreements
upon the commencement of employment or consulting relationships with us. These
agreements provide that all confidential information developed or made known to
the individual during the course of the individual's relationship with us is to
be kept confidential and not disclosed to third parties except in specific
circumstances. In the case of employees, the agreements provide that all
inventions conceived by the individual while in our employment shall be our
exclusive property. These agreements may not provide meaningful protection or
adequate remedies for our trade secrets in the event of unauthorized use or
disclosure of such information.

GOVERNMENT REGULATION

The production and marketing of INTEGRILIN and our ongoing research and
development of product candidates and other activities are subject to extensive
regulation by numerous government authorities in the United States and other
countries. The U.S. Food, Drug and Cosmetic Act and other federal statutes and
regulations govern or influence the development, testing, manufacture, labeling,
storage, approval, advertising, promotion, sale and distribution of drug
products. Satisfaction of such regulatory requirements typically takes several
years or more depending upon the type, complexity and novelty of the product and
requires the expenditure of substantial resources. For our currently marketed
product, INTEGRILIN, and for potential products in development, failure to
comply with applicable regulatory requirements after obtaining regulatory
approval can, among other things, result in the suspension of regulatory
approval, warning letters, recall of product, suspension of production and/or
distribution and possible civil and criminal sanctions.

The FDA's policies may change and additional governmental regulations may be
promulgated which could prevent or delay regulatory approval of our potential
products. We are unable to predict the likelihood of adverse governmental
regulation that might arise from future legislation or administrative action,
either in the United States or abroad. Furthermore, we may encounter problems in
clinical trials that will cause us or the FDA to delay or suspend clinical
trials. We may not be granted approval for potential products. Additionally, we
may not have sufficient resources to carry potential products through the
regulatory approval process.

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Clinical Testing

Our potential products must undergo rigorous preclinical testing and clinical
trials and an extensive regulatory approval process implemented by the FDA under
the U.S. Food, Drug and Cosmetic Act. Preclinical studies must be conducted in
compliance with Good Laboratory Practices regulations. Clinical testing must
meet requirements for Institutional Review Board oversight and informed consent,
as well as FDA prior review, oversight and Good Clinical Practice regulations.
Generally, clinical trials involve three phases and are subject to detailed
protocols, which must be reviewed by the FDA. The FDA or we may suspend clinical
trials at any time if either believes that the subjects participating in such
trials are being exposed to unacceptable health risks.

Data obtained from preclinical testing and clinical trials are susceptible to
varying interpretations that could delay, limit or prevent regulatory approvals.
We may not obtain regulatory approval for any of our potential products. If the
FDA grants regulatory approval, such approval will be limited to those specific
segments of the population for which the product is effective, as demonstrated
through clinical trials. Approval may entail ongoing requirements for
post-marketing studies. Product candidates developed by us alone or in
conjunction with others may not be proven to be safe and efficacious in clinical
trials or may not meet all of the applicable regulatory requirements needed to
receive or maintain marketing approval.

Other Regulation

Among the conditions for FDA approval of a pharmaceutical product is the
requirement that the manufacturer's quality control and manufacturing procedures
(either our own or a third-party manufacturer's) conform to Current Good
Manufacturing Practices, which must be followed at all times. In complying with
Current Good Manufacturing Practices regulations, pharmaceutical manufacturers
must expend resources and time to ensure compliance with specifications and
production, record keeping, quality control, reporting and other requirements.
See also "Manufacturing and Process Development."

Outside the United States, our ability to market a product is contingent upon
receiving marketing authorization from the appropriate regulatory authorities.
The requirements governing the conduct of clinical trials, marketing
authorization, pricing and reimbursement vary widely from country to country. At
present, foreign marketing authorizations are applied for at a national level,
although within the European Union, centralized procedures are available to
companies wishing to market a product in more than one European Union member
state. If the regulatory authorities are satisfied that adequate evidence of
safety, quality and efficacy has been presented, a marketing authorization will
be granted. This foreign regulatory approval process includes all of the risks
and potential delays associated with FDA approval set forth above.

We must also comply with other applicable federal, state and local laws and
regulations, such as the Occupational Safety and Health Act, the Environmental
Protection Act, the Nuclear Energy and Radiation Control Act, the Toxic
Substances Control Act, national restrictions on technology transfer,
regulations for the protection of human subjects in clinical studies and for
animal welfare in preclinical studies and import, export and customs regulation.
From time to time Congressional Committees and federal agencies have indicated
an interest in implementing further regulation of biotechnology and its
applications.

INSURANCE

We have significant and unpredictable risks of product liability claims in the
event that the use of our technology or products is alleged to have resulted in
adverse effects. Such risks will exist even with respect to any products that
receive regulatory approval for commercial sale. Our insurance coverage for
these risks may not be sufficient to satisfy any liability that may arise.
Additionally, adequate insurance coverage may not be available in the future at
an acceptable cost, if at all. A product liability claim may adversely affect
our business, financial condition, and results of operations.

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EMPLOYEES

As of March 1, 2000, we had 320 full-time employees, of whom 151 were in
research and development, 121 were in sales and marketing, and 48 were in
general and administrative functions. Our sales force is located throughout the
United States. All other employees are located at our facility in South San
Francisco, California.

None of our employees is represented by a collective bargaining agreement. We
consider our employee relations to be good. Our policy is to enter into
confidentiality agreements with our employees and consultants. See "Patents,
Propriety Rights and Licenses - Confidentiality Agreements".

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ADDITIONAL RISK FACTORS

Stockholders, potential investors in shares of our stock and holders of our
convertible subordinated notes should carefully consider the following risk
factors, in addition to other information in this Report. We are identifying
these risk factors as important factors that could cause our actual results to
differ materially from those contained in any written or oral forward-looking
statements made by or on behalf of COR. We are relying upon the safe-harbor for
forward-looking statements and any such statements made by or on behalf of COR
are qualified by reference to the following cautionary statements, as well as to
those set forth elsewhere in this Report.

FUTURE REVENUES FROM INTEGRILIN(R) (EPTIFIBATIDE) INJECTION MAY BE LESS THAN
EXPECTED.

Our prospects are highly dependent upon increasing the sales of our only
commercial product, INTEGRILIN. Our revenues to date have consisted largely of
contract revenue from development and milestone payments and co-promotion
revenue from product sales by Schering of INTEGRILIN. If sales of INTEGRILIN
fail to increase, it would have a material adverse effect on our business,
financial condition, and results of operations.

A number of factors may affect the rate and breadth of market acceptance of
INTEGRILIN, including:

- The perception by physicians and other members of the health care
community on the safety and efficacy of INTEGRILIN

- Acceptance of INTEGRILIN outside the United States

- Our dependence upon Schering's commitment to market and sell
INTEGRILIN

- The price of INTEGRILIN relative to other drugs or competing
treatment modalities

- The availability of third-party reimbursement

- The effectiveness of our sales and marketing efforts with
Schering-Plough

- The need to increase usage of INTEGRILIN throughout the treatment
process

- Side effects or unfavorable publicity concerning INTEGRILIN or other
drugs in its class

WE HAVE A HISTORY OF OPERATING LOSSES AND ARE UNCERTAIN OF FUTURE PROFITABILITY.

Historically, our expenses have exceeded revenues. We incur significant expenses
in developing, training, maintaining, and managing our sales organization. The
cost of maintaining our sales force may exceed INTEGRILIN product revenues, and
our direct marketing and sales efforts may not be successful. We had an
accumulated deficit as of December 31, 1999, of approximately $215,000,000.
These losses may increase as we expand our commercialization and research and
development activities, and such losses may fluctuate significantly from quarter
to quarter. We may not sustain or increase our contract revenues derived from
product sales or achieve profitable operations.

WE MAY NOT BE ABLE TO COMPETE EFFECTIVELY IN THE CARDIOVASCULAR DISEASE MARKET.

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pharmaceutical and biotechnology companies may also prove to be significant
competitors, particularly through collaboration arrangements with large
pharmaceutical companies. Many of these competitors have cardiovascular products
approved or in development, and operate large, well-funded cardiovascular
research and development programs. We must also compete with academic
institutions, governmental agencies, and other public and private research
organizations that conduct research in the cardiovascular field, seek patent
protection for their discoveries and establish collaboration arrangements for
product and clinical development and marketing.

IF OUR COLLABORATION RELATIONSHIPS ARE NOT SUCCESSFUL, WE MAY NOT BE ABLE TO
EFFECTIVELY DEVELOP AND MARKET OUR PRODUCTS.

We are currently engaged in a number of strategic collaborations with other
companies, consultants, universities and medical centers. Our main collaboration
agreement is with Schering for the sale, marketing and additional development of
INTEGRILIN(R) (eptifibatide) Injection.

Our collaborative relationships may not be successful or lead to the development
or commercialization of any particular product or product opportunity in the
ongoing development and marketing of INTEGRILIN. Although under our current
agreements we work exclusively with our collaborators within a defined field for
a defined period, a collaborator or collaborators may terminate its or their
agreement with us or separately pursue alternative products, therapeutic
approaches, or technologies as a means of developing treatments for the diseases
targeted by us or a collaboration. For these and other reasons, even if a
collaborator continues its contributions to the arrangement with us, it may
nevertheless determine not to actively pursue the development or
commercialization of any resulting products. In that event, our ability to
pursue potential products could be severely limited.

We evaluate, on an ongoing basis, potential collaborations where relationships
may complement and expand our research, development, sales, or marketing
capabilities. We anticipate that in the future we may need to enter into a new
collaborative relationship to jointly develop and market cromafiban and other
potential products. Any arrangements may limit our flexibility in pursuing
alternatives for the commercialization of our products. We may not be able to
establish any additional collaboration agreements. If established, such
arrangements may not be successful.

OUR BUSINESS MAY BE HARMED IF OUR THIRD-PARTY MANUFACTURERS ARE NOT ABLE TO
PROVIDE US WITH ADEQUATE SUPPLIES OF OUR PRODUCTS.

We currently have no manufacturing facilities and, accordingly, rely on third
parties for clinical and commercial production of INTEGRILIN and for clinical
production of product candidates. If the third-party manufacturers or suppliers
were to cease production or otherwise fail to supply us or we were unable to
contract on acceptable terms for manufacturing services with others, our ability
to produce INTEGRILIN and to conduct preclinical testing and clinical trials of
product candidates, would be adversely affected. This could potentially result
in product supply and distribution shortages of INTEGRILIN and delay of
regulatory approval and new development of product candidates. These results
could materially impair our competitive position and could have a material
adverse effect on our business, financial condition and results of operations.

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OUR REVENUE MAY BE AFFECTED NEGATIVELY BY REIMBURSEMENT LEVELS AND PRICING
LIMITATIONS.

In both domestic and foreign markets, sales of our products may be affected by
the availability of reimbursement from third-party payors, including government
health administration authorities, managed care providers, private health
insurers and other organizations. In addition, third-party payors may challenge
the price and cost effectiveness of our products. In many major markets outside
of the United States, pricing approval is required before sales can commence.
Significant uncertainty exists as to the reimbursement status of approved health
care products.

We may not be able to obtain or maintain our desired price for our products. Our
products may not be considered cost effective. Also, adequate third-party
reimbursement may not be available to enable us to maintain price levels
sufficient to realize an appropriate return on our investment in product
development. Legislation and regulations affecting the pricing of
pharmaceuticals may change. If adequate coverage and reimbursement levels are
not provided by the government and third-party payors for our products, the
market acceptance of these products would be adversely affected, which would
have a material adverse effect on our business, financial condition and results
of operations.

WE MAY BE UNABLE TO OBTAIN REGULATORY APPROVAL FOR OUR POTENTIAL PRODUCTS.

We must obtain regulatory approval for the commercial sale of any our potential
products or to promote INTEGRILIN(R) (eptifibatide) Injection for expanded
indications. We must demonstrate through preclinical testing and clinical trials
and, to the FDA's satisfaction, that each product is safe and effective for use
in indications for which approval is requested. The results from preclinical
testing and early clinical trials may not be predictive of results obtained in
large clinical trials. Companies in the pharmaceutical and biotechnology
industries, including us, have suffered significant setbacks in various stages
of clinical trials, even in advanced clinical trials after promising results had
been obtained in earlier trials.

The development of safe and effective products is highly uncertain and subject
to numerous risks. Product candidates that may appear to be promising in
development may not reach the market for a number of reasons. Product candidates
may:

- be found ineffective or cause harmful side effects during clinical
trials

- take longer to progress through clinical trials than had been
anticipated

- fail to receive necessary regulatory approvals

- prove impracticable to manufacture in commercial quantities at
reasonable cost and with acceptable quality

- fail to achieve market acceptance

Completion of research, preclinical testing and clinical trials may take many
years and the length of time varies substantially with the type, complexity,
novelty and intended use of the product. Delays or rejections may be encountered
based upon many factors. Our current development programs may not be
successfully completed. Our regulatory applications to conduct clinical trials
may not be allowed to proceed by the FDA or other regulatory authorities, or
clinical trials may not commence as planned.

In addition, due to the substantial demand for clinical trial sites in the
cardiovascular area, we may have difficulty obtaining sufficient patient
populations or clinician support to conduct our clinical trials as planned and
may have to expend substantial additional funds to obtain access to resources or
delay or modify our plans significantly.

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IF WE ARE UNABLE TO PROTECT OUR PATENTS AND PROPRIETARY RIGHTS, WE MAY NOT BE
ABLE TO COMPETE SUCCESSFULLY.

We rely on patent and trade secret protection for significant new technologies,
products and processes because of the long development time, uncertainty and
high cost associated with bringing a new product to the marketplace. The
enforceability of patents issued to companies in this industry can be highly
uncertain and involve complex legal and technical questions for which the legal
principles are largely unresolved. Our success will depend in part on our
ability to obtain and enforce patent protection for our technology both in the
United States and other countries. While we are seeking and/or maintaining
patents for INTEGRILIN(R) (eptifibatide) Injection and our product candidates,
patents may not issue and issued patents may afford limited or no protection.
Additionally, we may not be successful in enforcing our patents and avoiding
infringement of patents granted to others.

We may be required to obtain licenses to patents or other proprietary rights
from third parties. Licenses required under any patents or proprietary rights
may not be made available on terms acceptable to us, if at all. If we do not
obtain required licenses, we may encounter delays in product development while
attempting to redesign products or methods or we could find the development,
manufacture or sale of such products requiring licenses to be foreclosed.
Further, we could incur substantial costs in defending any patent litigation
brought against us or in asserting our patent rights, including those rights
licensed to us by others. See "Legal Proceedings."

OUR COMMON STOCK PRICE IS VOLATILE AND AN INVESTMENT IN OUR STOCK COULD SUFFER A
DECLINE IN VALUE.

The market prices for securities of pharmaceutical and biotechnology companies,
including our common stock, have historically been volatile. The market has from
time to time experienced significant price and volume fluctuations that are
unrelated to the operating performance of particular companies. The following
are some of the factors that may have a significant effect on the market price
of our common stock:

- fluctuations in our operating results

- announcements of technological innovations or new therapeutic
products by us or our competitors

- announcements regarding collaborative agreements

- governmental regulation

- our clinical trial results

- developments in patent or other proprietary rights

- public concern as to the safety of drugs developed by us or others

- comments and expectations of results made by securities analysts

- general market conditions

In particular, the realization of any of the risks described in this Report
could have a significant and adverse impact on the market price of our common
stock.

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SUBSTANTIAL LEVERAGE MAY ADVERSELY AFFECT OUR CASH FLOW AND ABILITY TO MEET OUR
DEBT SERVICE OBLIGATIONS

In February 2000, we increased our outstanding debt by completing a private
placement of $300,000,000 5.0% Convertible Subordinated Notes due March 1, 2007
(the Notes). As a result, our principal and interest payment obligations
increased substantially. The Notes are unsecured and subordinated in right of
payment to all of our existing and future senior debt and may be convertible
under certain conditions. We expect from time to time to enter into additional
financing arrangements to finance capital expenditures and as future needs
arise.

If a change of control were to occur, holders of the Notes have the right to
require us to redeem all or a portion of the holder's Notes. Although the
Indenture governing the Notes allows us, subject to certain conditions, to pay
the redemption price in shares of our common stock, if a change of control were
to occur, we may not have sufficient funds to pay the redemption price for all
of the Notes tendered by the holders.

Our substantial leverage could have significant negative consequences,
including:

- causing us to be unable to generate cash sufficient to pay the
principal or interest on our debt when due

- increasing our vulnerability to general adverse economic and industry
conditions

- limiting our ability to obtain additional financing

- requiring the dedication of a substantial portion of our expected
cash flow from operations to service our indebtedness, thereby
reducing the amount of our expected cash flow available for other
purposes, including capital expenditures

- limiting our flexibility in planning for, or reacting to, changes in
our business and the industry in which we compete

- placing us at a possible competitive disadvantage to less leveraged
competitors

WE MAY REQUIRE ADDITIONAL FUNDS, WHICH MAY BE DIFFICULT TO OBTAIN IN ORDER TO
CONTINUE OUR BUSINESS AS PLANNED.

We require substantial funds to market INTEGRILIN(R) (eptifibatide) Injection
and conduct the costly and time-consuming research, preclinical testing and
clinical trials necessary to develop and optimize our technology and potential
products, to establish manufacturing, marketing and sales capabilities for
product candidates and to bring any such products to market. Our future capital
requirements will depend on many factors, including:

- product commercialization activities

- continued scientific progress in the research and development of our
technology and drug programs

- our ability to establish and maintain collaboration arrangements

- progress with preclinical testing and clinical trials

- the time and costs involved in obtaining regulatory approvals

- the costs involved in preparing, filing, prosecuting, maintaining and
enforcing patent claims or trade secrets

We may seek ongoing funding through collaboration arrangements and public or
private financings, including equity and debt financings. Additional funding may
not be available on favorable terms, if at all. In that event, we may need to
delay or curtail our research and development activities to a significant
extent.

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IF WE DO NOT ATTRACT AND RETAIN KEY EMPLOYEES AND CONSULTANTS, OUR BUSINESS
COULD BE IMPAIRED.

We are highly dependent on the principal members of our scientific and
management staff. In addition, we rely on consultants to assist us in
formulating our research and development strategy. Attracting and retaining
qualified personnel and consultants are critical to our success. We face
competition for qualified individuals from numerous pharmaceutical and
biotechnology companies, universities and other research institutions. If we are
not able to attract and retain these individuals, our business could be
impaired.

WE MAY BE SUBJECT TO PRODUCT LIABILITY CLAIMS AND OUR INSURANCE COVERAGE MAY NOT
BE ADEQUATE TO COVER THESE CLAIMS.

The testing, marketing and sale of human pharmaceutical products expose us to
significant and unpredictable risks of product liability claims in the event
that the use of our technology or products is alleged to have resulted in
adverse effects. These risks will exist even with respect to any products that
receive regulatory approval for commercial sale. Although we have obtained
liability insurance for our products, there can be no assurance that it will be
sufficient to satisfy any liability that may arise. There also can be no
assurance that adequate insurance coverage will be available in the future at an
acceptable cost, if at all, or that a product liability claim would not
adversely affect our business, financial condition or results of operations.

ACCIDENTS RESULTING FROM THE USE OF HAZARDOUS MATERIALS IN OUR BUSINESS MAY
RESULT IN LIABILITY.

Our research and development involves the controlled use of hazardous materials,
chemicals, and various radioactive substances. Although we believe that our
safety procedures for handling and disposing of such materials comply with the
standards prescribed by state and federal regulations, the risk of accidental
contamination or injury from these materials cannot be completely eliminated. In
the event of such an accident, we could be held liable for any damages that
result and any such liability could exceed our resources and have a material
adverse effect on our business, financial condition and results of operations.

ANTI-TAKEOVER EFFECTS OF DELAWARE LAW AND CERTAIN CHARTER PROVISIONS

Our Board of Directors has the authority to issue up to 5,000,000 shares of
Preferred Stock and to determine the price, rights, preferences and privileges
of those shares without any further vote or action by our stockholders. The
rights of the holders of Common Stock will be subject to and may be adversely
affected by, the rights of the holders of any Preferred Stock that may be issued
in the future. While we have no present intention to issue shares of Preferred
Stock, such issuance, while providing desirable flexibility in connection with
possible acquisitions and other corporate purposes, could have the effect of
making it more difficult for a third party to acquire a majority of our
outstanding voting stock.

In addition, we are subject to the anti-takeover provisions of Section 203 of
the Delaware General Corporation Law, which prohibits us from engaging in a
"business combination" with an "interested stockholder" for a period of three
years after the date of the transaction in which the person became an interested
stockholder, unless the business combination is approved in a prescribed manner.
The application of Section 203 could have the effect of delaying or preventing a
change in our control.

In January 1995, our Board of Directors adopted a Preferred Share Purchase
Rights Plan, commonly referred to as a "poison pill." In addition, our Restated
Certificate of Incorporation (the "Restated Certificate") does not permit
cumulative voting. The Restated Certificate also includes a "Fair Price
Provision" that requires the approval of the holders of at least 66 2/3% of our
voting stock as a condition to a merger or certain other business transactions
with or proposed by, a holder of 15% or more of our voting stock, except where
disinterested Board or stockholder approval is obtained or certain minimum price
criteria and other procedural requirements are met. These provisions and other
provisions of the Restated Certificate, our Company bylaws and Delaware
corporate law, may have the effect of deterring hostile takeovers or delaying or
preventing changes in control or management of COR, including transactions in
which stockholders might otherwise receive a premium for their shares over then
current market prices.

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RISKS RELATED TO THE YEAR 2000 ISSUE

We use and rely on a wide variety of information technologies, computer systems
and scientific equipment containing computer-related components. Some of our
older computer software programs and equipment may use two digit fields rather
than four digit fields to define the applicable year (i.e., "98" in the computer
code refers to the year "1998"). As a result, time-sensitive functions of those
software programs and equipment may misinterpret dates after January 1, 2000 to
refer to the twentieth century rather than to the twenty-first century (i.e.,
"02" could be interpreted as "1902" rather than "2002"). This condition is
commonly referred to as the Year 2000 Issue.

We have not experienced any operational problems related to the Year 2000 Issue.
However, we will continue to monitor key computer systems and equipment in the
event that Year 2000 Issues may arise in the future. The total cost of systems
assessments and modifications related to the Year 2000 Issue has not been
material to date, and will be funded in the future, if necessary, through
working capital.

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OUR EXECUTIVE OFFICERS

The names of our executive officers as of March 1, 2000 and certain information
about them are set forth below.

Name Age Position
- ---------------------- --- ---------------------------------------------------------------

Vaughn M. Kailian 55 President, Chief Executive Officer and Director

Patrick A. Broderick 41 Senior Vice President, General Counsel and Corporate Secretary

Charles J. Homcy, M.D. 51 Executive Vice President, Research and Development and Director

Mark D. Perrin 43 Executive Vice President, Commercial Operations

Lee M. Rauch 46 Senior Vice President, Corporate Development

Vaughn M. Kailian has served as President, Chief Executive Officer and as a
Director since March 1990. From 1967 to 1990, Mr. Kailian was employed by Marion
Merrell Dow, Inc., a pharmaceutical company and its predecessor companies, in
various general management, product development, marketing and sales positions.
Mr. Kailian served as Corporate Vice President of Global Commercial Development,
Marion Merrell Dow, Inc.; President and General Manager, Merrell Dow USA; Vice
President, Marketing and Sales, Merrell Dow USA; and Vice President, Marketing
and Sales of Merrell Dow, Europe, Africa and the Middle East. Mr. Kailian holds
a B.A. from Tufts University. Mr. Kailian also serves as a director of Amylin
Pharmaceuticals and Axys Pharmaceutical Inc.

Patrick A. Broderick has served as Senior Vice President, General Counsel and
Corporate Secretary since January 1999. From 1993 until he joined COR, Mr.
Broderick held various legal positions with McKesson HBOC, Inc., last serving as
Senior Counsel. In this capacity, Mr. Broderick was the legal counsel for drug
manufacturers' services for McKesson HBOC, Inc. From 1994 to 1999, Mr. Broderick
was also counsel to various subsidiaries of McKesson HBOC, Inc., including
Healthcare Delivery Systems, Inc., McKesson Bioservices Corporation and J.
Knipper and Company, Inc. From 1988 to 1992, Mr. Broderick practiced general
corporate law with Morrison & Foerster, prior to which he practiced business
litigation with McCutchen, Doyle, Brown & Enersen. Mr. Broderick received his
B.A. from Harvard College and his J.D. from Yale Law School.

Charles J. Homcy, M.D. has served as our Executive Vice President, Research and
Development since March 1995 and as a Director since January 1998. Since 1997,
Dr. Homcy has been Clinical Professor of Medicine, University of California at
San Francisco Medical School and Attending Physician at the San Francisco VA
Hospital. From 1994 until he joined COR, Dr. Homcy was President of the Medical
Research Division of American Cyanamid Company-Lederle Laboratories, a
pharmaceutical company (now a division of Wyeth-Ayerst Laboratories.) From 1990
until 1994, Dr. Homcy was Executive Director of the Cardiovascular and Central
Nervous System Research Section at Lederle Laboratories, a pharmaceutical
company. From 1991 to 1995, Dr. Homcy also served as an attending physician at
The Presbyterian Hospital, College of Physicians and Surgeons, at Columbia
University in New York. From 1979 to 1990, he was an attending physician at
Massachusetts General Hospital and an Associate Professor of Medicine at Harvard
Medical School. Dr. Homcy received his B.A. and his M.D. degrees from the Johns
Hopkins University in Baltimore.

Mark D. Perrin has served as our Executive Vice President, Commercial Operations
since November 1995. From 1992 until he joined COR, Mr. Perrin was Vice
President, Marketing and Sales, of Burroughs Wellcome Company, a pharmaceutical
company. From 1979 to 1992, Mr. Perrin held various sales and marketing
positions at American Cyanamid Company-Lederle Laboratories, a pharmaceutical
company (now a division of Wyeth-Ayerst Laboratories), last serving as Vice
President and General Manager of Lederle Pharmaceuticals. Mr. Perrin received
his B.S. from Fordham University and his Masters of Management from Northwestern
University.

Lee M. Rauch has served as our Senior Vice President, Corporate Development
since January 1999. From 1997 to 1999, Ms. Rauch worked for the Mitchell Madison
Group where she was a Partner in the Healthcare Practice with leadership
responsibility for the Pharma/Supply sector. From 1995 to 1997, Ms. Rauch headed
Healthcare Strategies, a consulting practice serving clients in biotechnology,
healthcare information and medical devices. From 1989 to 1995, Ms. Rauch held a
variety of corporate positions at Syntex Corporation, including Vice President
of Strategic Marketing, Vice President of New Product Planning, Director of
Therapy Area Planning for cardiovascular and central nervous system disease
areas and Director of Business Development. Prior to 1989, Ms. Rauch worked

21
23

for various companies including McKinsey & Co., Inc., Rohm and Haas Company and
American Cyanamid. Ms. Rauch received her B.A. from Arizona State University and
her M.B.A from the University of Chicago.

ITEM 2. PROPERTIES

We lease and occupy facilities consisting of approximately 126,000 square feet
of laboratory and office space in South San Francisco, California. Our lease
expires in November 2004. We may require additional laboratory and office space
as we expand our operations. We believe that additional space will be available
on commercially acceptable terms. We currently have no production facilities.

ITEM 3. LEGAL PROCEEDINGS

ITEM 4. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

Not applicable.

22
24

PART II

ITEM 5. MARKET FOR REGISTRANT'S COMMON EQUITY AND RELATED STOCKHOLDER MATTERS

Our common stock trades on The Nasdaq Stock Market(R) under the symbol "CORR."
The following table sets forth, for the calendar periods indicated, the high and
low sale prices per share of our common stock on The Nasdaq Stock Market(R).
These prices represent quotations among dealers without adjustments for retail
markups, markdowns or commissions.

1999 High Low 1998 High Low
- -------------- ------ ------ -------------- ------ ------

First Quarter $14.88 $ 8.13 First Quarter $24.88 $ 8.63
Second Quarter $15.88 $ 8.75 Second Quarter $22.75 $12.13
Third Quarter $27.50 $14.13 Third Quarter $16.00 $ 6.81
Fourth Quarter $30.63 $16.88 Fourth Quarter $14.13 $ 6.69

As of March 1, 2000 there were approximately 474 holders of record of COR common
stock. On March 1, 2000, the last reported sale price on The Nasdaq Stock
Market(R) for our common stock was $93.41 per share.

DIVIDEND POLICY

We have not paid any dividends since our inception and do not intend to pay any
dividends on our common stock in the foreseeable future.

RECENT SALES OF CONVERTIBLE DEBT SECURITIES

In February 2000 we completed a private placement of $300,000,000 5.0%
Convertible Subordinated Notes due March 1, 2007 to qualified institutional
investors, underwritten by Goldman, Sachs & Co., Chase Securities Inc., CIBC
World Markets Corp., FleetBoston Robertson Stephens Inc. and Warburg Dillon Read
LLC. The offering price of the Notes was 100% of the principal amount of the
Notes. We incurred issuance costs related to this offering of approximately
$11,000,000 (including aggregate underwriting discounts and commissions) which
we expect to amortize to interest expense over the life of the Notes.

The Notes were offered and sold in the United States to qualified institutional
buyers in reliance on Rule 144A of the Securities Act of 1933, as amended. The
Notes and common stock issuable upon conversation of the Notes are not
transferable except in accordance with certain restrictions. The Notes may not
be offered or sold in the United States absent registration under the Securities
Act of 1933, as amended, and applicable state securities laws or available
exemptions from the registration requirements.

The holders of the Notes may convert the Notes into shares of our common stock
at a conversion rate of 14.8028 shares per $1,000 principal amount of Notes,
which is equivalent to a conversion price of $67.56 per share. The conversion
rate is subject to adjustment in certain events. The Notes are convertible at
any time before the close of business on the maturity date, March 1, 2007,
unless we have previously redeemed or repurchased the Notes. Holders of notes
called for redemption or repurchase will be entitled to convert them up to and
including, but not after, the business day immediately preceding the date fixed
for redemption or repurchase, as the case may be.

We intend to use the proceeds from the Notes for marketing and selling
activities related to INTEGRILIN(R) (eptifibatide) Injection, research and
development activities and general corporate purposes. Pending such uses, the
proceeds from the Notes will be invested in highly liquid and high quality debt
securities in accordance with our investment policy.

23
25

ITEM 6. SELECTED FINANCIAL DATA

The selected financial data set forth below should be read in conjunction with
"Management's Discussion and Analysis of Financial Condition and Results of
Operations" and the Financial Statements and Notes thereto included elsewhere in
this Report. The statement of operations data for the years ended December 31,
1999, 1998 and 1997 and the balance sheet data at December 31, 1999 and 1998,
are derived from the audited financial statements of COR included elsewhere in
this Report. The statement of operations data for the years ended December 31,
1996 and 1995 and the balance sheet data as of December 31, 1997, 1996 and 1995,
are derived from audited financial statements not included herein. We have not
declared or paid cash dividends on our common stock since inception and do not
intend to pay any cash dividends in the foreseeable future.

Year Ended December 31,
------------------------------------------------------------
1999 1998(i) 1997 1996 1995
-------- -------- -------- -------- --------
STATEMENT OF OPERATIONS DATA: (in thousands, except per share data)

Contract Revenues:
Copromotion revenue $ 34,132 $ 3,933 $ -- $ -- $ --
Milestone revenue 12,000 32,000 8,000 9,000 6,000
Development and other contract revenue 10,526 6,030 14,190 9,755 25,850
-------- -------- -------- -------- --------
Total contract revenues 56,658 41,963 22,190 18,755 31,850
-------- -------- -------- -------- --------
Expenses:
Cost of copromotion revenue 22,471 11,803 -- -- --
Research and development 36,563 39,915 47,831 50,791 37,392
Marketing, general and administrative 26,018 21,474 10,067 7,303 6,029
-------- -------- -------- -------- --------
Total expenses 85,052 73,192 57,898 58,094 43,421
-------- -------- -------- -------- --------
Loss from operations (28,394) (31,229) (35,708) (39,339) (11,571)
Interest income, net 2,324 3,615 2,216 2,793 4,040
-------- -------- -------- -------- --------
Net loss $(26,070) $(27,614) $(33,492) $(36,546) $ (7,531)
======== ======== ======== ======== ========
Basic and diluted net loss per share $ (1.05) $ (1.14) $ (1.60) $ (1.86) $ (0.39)
======== ======== ======== ======== ========
Shares used in computing
basic and diluted net loss per 24,822 24,141 20,952 19,636 19,360

(i) INTEGRILIN(R) (eptifibatide) Injection was launched with Schering in June
1998 in the United States.

December 31,
-----------------------------------------------------------------
1999 1998 1997 1996 1995
--------- --------- --------- --------- ---------
BALANCE SHEET DATA: (in thousands)

Cash, cash equivalents and short-term investments $ 45,753 $ 75,205 $ 82,569 $ 53,134 $ 84,834
Total assets 87,897 103,093 95,385 71,245 100,906
Long-term obligations 2,925 3,261 2,817 3,365 4,574
Total liabilities 51,141 48,497 16,987 20,803 18,669
Accumulated deficit (215,234) (189,164) (161,550) (128,058) (91,512)
Total stockholders' equity 36,756 54,596 78,398 50,442 82,237

24
26

ITEM 7. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
OF OPERATIONS

In addition to the historical data contained herein, the following discussion
contains forward-looking statements that involve risks and uncertainties. Our
actual results could differ materially from those anticipated in these
forward-looking statements as a result of certain factors, including those set
forth elsewhere in this Report.

OVERVIEW

We are dedicated to the discovery, development and commercialization of novel
pharmaceutical products to establish new standards of care for the treatment and
prevention of severe cardiovascular diseases. We have incurred a cumulative net
loss of $215,234,000 through December 31, 1999. We have funded our operations
primarily through public equity financings and proceeds from collaboration
research and development agreements.

INTEGRILIN(R) (eptifibatide) Injection is the first product that we have taken
from discovery to commercialization. Approved by the FDA in May 1998, INTEGRILIN
is indicated for the treatment of patients with an acute coronary syndrome and
patients who undergo angioplasty procedures. The acute coronary syndrome
indication includes patients with unstable angina and non-Q-wave myocardial
infarction, whether they receive medical treatment or undergo angioplasty.
Launched in June 1998 in the United States in conjunction with Schering,
INTEGRILIN is the only drug in its class that is approved by the FDA for use in
both acute coronary syndromes and in angioplasty. Along with Schering we
co-promote the drug in the United States and share any profits or losses.

In July 1999 Schering announced that the European Union's Commission of the
European Communities had granted marketing authorization to INTEGRILIN for the
prevention of early myocardial infarction in patients with acute coronary
syndromes, including those who are managed medically and/or those who undergo
angioplasty. In connection with this approval, Schering paid to us a $12,000,000
milestone. Schering markets INTEGRILIN in Europe as our exclusive licensee on a
royalty-bearing basis. INTEGRILIN has also received regulatory approval in a
number of countries outside the European Union and the United States and is
marketed in those countries by Schering as our exclusive licensee on a
royalty-bearing basis.

Total sales of INTEGRILIN, as reported to us by Schering, were $63,700,000 for
the twelve months ended December 31, 1999 and were $12,200,000 from launch in
June 1998 through December 31, 1998. Product sales reported by Schering for the
twelve months ended December 31, 1999 or for the period from launch in June 1998
to December 31, 1998 are not necessarily indicative of product sales for any
future period.

With Schering, we are conducting or have conducted Phase II clinical trials of
INTEGRILIN with different fibrinolytics in the setting of acute myocardial
infarction. Both of our companies also sponsor additional clinical trials of
INTEGRILIN in a variety of clinical settings.

In addition to our commercial activities, we continue to pursue a wide array of
research and development programs. Our next potential product, cromafiban, has
the potential to help prevent a wide variety of diseases, including acute
myocardial infarction, unstable angina, thrombotic stroke and peripheral
arterial occlusive disease. Cromafiban is an oral GP IIb-IIIa inhibitor that
prevents platelet aggregation. In addition to having a high affinity and
specificity for GP IIb-IIIa, cromafiban's plasma concentrations have indicated a
sufficiently long elimination half-life to allow

25
27

for once-daily dosing with a low peak-to-trough ratio. No food interactions have
been observed. Minor bleeding was the most prevalent complication encountered
during cromafiban therapy in clinical trials conducted to date. We are also
conducting preclinical research and development in several other cardiovascular
programs.

RESULTS OF OPERATIONS

Fiscal Years Ended December 31, 1999, 1998 and 1997

Total contract revenues, which include copromotion, milestone, and development
and other contract revenue, were $56,658,000 in 1999 compared to $41,963,000 in
1998 and $22,190,000 in 1997. Copromotion revenue related to the sales of
INTEGRILIN(R) (eptifibatide) Injection by Schering was $34,132,000 in 1999
compared to $3,933,000 from launch in June 1998 through December 31, 1998 and $0
in 1997. Milestone revenue in 1999 consists of $12,000,000 from Schering related
to the marketing authorization granted to INTEGRILIN in the European Union for
certain indications. Milestone revenue in 1998 consists of $24,000,000 from
Schering in connection with regulatory approval of INTEGRILIN in the United
States and $8,000,000 from Schering in connection with the application for
regulatory approval of INTEGRILIN in the European Union. Milestone revenue in
1997 consists of $8,000,000 from Schering in connection with the completion of
PURSUIT, a large Phase III clinical trial for INTEGRILIN. Development and other
contract revenue was $10,526,000 in 1999 compared to $6,030,000 in 1998 and
$14,190,000 in 1997. Development and other contract revenue varies due to
fluctuations in development activities. We expect total contract revenues to
continue to fluctuate in the future.

Cost of copromotion revenue was $22,471,000 in 1999 compared to $11,803,000 from
June 1998 through December 31, 1998 and $0 in 1997, consistent with our joint
commercial launch of INTEGRILIN with Schering in the United States in June 1998
and increased sales of INTEGRILIN in 1999. Cost of copromotion revenue includes
certain manufacturing-related and marketing expenses incurred in connection with
the collaboration with Schering.

Research and development expenses were $36,563,000 in 1999 compared to
$39,915,000 in 1998 and $47,831,000 in 1997. The decrease in 1999 compared to
1998 and the decrease in 1998 compared to 1997 were due in part to the timing of
clinical trial activities, offset in part by increases in headcount and other
research, development and clinical activities associated with other potential
products. We expect research and development expenses to increase over the next
several years, although the timing of certain of these expenses may depend on
the timing and phase of, and indications pursued in, additional clinical trials
of INTEGRILIN and other product candidates in development.

Marketing, general and administrative expenses were $26,018,000 in 1999 compared
to $21,474,000 in 1998 and $10,067,000 in 1997. The increase in 1999 compared to
1998 and the increase in 1998 compared to 1997 were primarily due to the
addition of marketing and sales personnel for the commercialization of
INTEGRILIN, as well as increased staffing and administrative expenses associated
with general corporate activities. We expect marketing, general and
administrative costs to continue to increase over the next several years.

Interest income (net) was $2,324,000 in 1999 compared to $3,615,000 in 1998 and
$2,216,000 in 1997. The decrease in 1999 compared to 1998 and the increase in
1998 compared to 1997 were primarily due to changes in cash and investment
balances and the amount of debt obligations.

We incurred a net loss of $26,070,000 in 1999 and, accordingly, no provision for
federal or state income taxes was recorded. At December 31, 1999, we had federal
net operating tax loss carryforwards of approximately $174,100,000. Our ability
to use our net operating loss carryforwards may be subject to an annual
limitation in future periods. We believe, however, that this limitation will not
have a material impact on our future operating results.

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28

LIQUIDITY AND CAPITAL RESOURCES

We had available cash, cash equivalents and short-term investments of
$45,753,000 at December 31, 1999. We invest cash in excess of our immediate
requirements according to our investment policy. The primary objective of our
investment activities is to preserve principal while at the same time maximizing
yields without significantly increasing risk. From inception, we have funded our
operations primarily through public equity financings and proceeds from
collaboration agreements, including proceeds related to the sales of
INTEGRILIN(R) (eptifibatide) Injection by Schering. Additional funding has come
from private equity financings, grant revenues, interest income and property and
equipment financings.

Our cash used in operating activities and additions to capital equipment were
$35,569,000 in 1999 compared to $10,429,000 in 1998 and $30,968,000 in 1997. The
increase in 1999 compared to 1998 and the decrease in 1998 compared to 1997 were
primarily due to the timing of activities related to our agreement with
Schering, including milestone revenues received from Schering, and increased
expenses. Our cash requirements for operating activities and additions to
capital equipment may increase in future periods. The timing of these cash
requirements may vary from period to period depending on the timing and phase
of, and indications pursued in, additional clinical trials of INTEGRILIN and
clinical trials of product candidates in development. Cash provided by financing
activities was $6,416,000 in 1999, $2,895,000 in 1998 and $60,443,000 in 1997.
These amounts result primarily from the issuance of Common Stock, including a
public equity financing in 1997, and the net effect of property and equipment
financings.

In February 2000 we issued in a private placement $300,000,000 5.0% Convertible
Subordinated Notes. The Notes mature on March 1, 2007, are unsecured and may be
convertible under certain conditions. The Notes are subordinated in right of
payment to all of our existing and future senior debt (as defined in the
Indenture governing the Notes) and do not restrict us from incurring additional
senior debt.

We expect our cash requirements will increase due to costs related to
continuation and expansion of research and development, including clinical
trials and increased marketing, sales, general and administrative activities. We
anticipate that our existing capital resources and interest earned thereon will
enable us to maintain our current level of operations for the next several
years. However, our capital requirements may change depending on numerous
factors, including the progress of our research and development programs, the
scope and results of preclinical and clinical studies and the number and nature
of the indications we pursue in clinical studies. Our capital requirements may
also change due to the timing of regulatory approvals, technological advances,
determinations as to the commercial potential of our future products and the
status of competitive products. Our capital requirements may also change because
of other unanticipated circumstances. In addition, expenditures may depend on
the establishment and maintenance of collaboration relationships with other
companies, the availability of financing and other factors. We may need to raise
substantial additional funds in the future. Such funds may not be available on
favorable terms, if at all. If such funds are unavailable, we may need to delay
or curtail our research and development activities to a significant extent.

Our business is subject to significant risks including, but not limited to, the
successful sales, distribution and manufacture of INTEGRILIN, the success of our
research and development activities, the length and expense of obtaining
regulatory approval and the results of clinical trials. Other significant risks
include uncertainty related to the availability of future funding, uncertainty
related to third-party reimbursement for our product and/or potential products,
and uncertainty related to our collaborative relationships. In addition, our
product candidates may be difficult to manufacture on a large scale,
uneconomical to market or precluded from commercialization by proprietary rights
of other parties. Additional expenses, delays and lost opportunities that may
arise out of these and other risks could have a material adverse effect on our
business, financial condition and results of operations.

27
29

YEAR 2000 COMPLIANCE

ITEM 7A. FINANCIAL MARKET RISKS

We are exposed to interest rate risk on our investments of excess cash. The
primary objective of our investment activities is to preserve principal while at
the same time maximizing yields without significantly increasing risk. To
achieve this objective, we invest in highly liquid and high quality debt
securities. To minimize the exposure due to adverse shifts in interest rates, we
invest in short-term securities with maturities of less than three years. If a
10% change in interest rates were to have occurred on December 31, 1999, such a
change would not have had a material effect on the fair value of our investment
portfolio as of that date. Due to the nature of our short-term investments, we
have concluded that we do not have a material financial market risk exposure.

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30

ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

REPORT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS

Board of Directors and Stockholders
COR Therapeutics, Inc.

We have audited the accompanying balance sheets of COR Therapeutics, Inc. as of
December 31, 1999 and 1998 and the related statements of operations,
stockholders' equity and cash flows for each of the three years in the period
ended December 31, 1999. These financial statements are the responsibility of
the Company's management. Our responsibility is to express an opinion on these
financial statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of COR Therapeutics, Inc. at
December 31, 1999 and 1998 and the results of its operations and its cash flows
for each of the three years in the period ended December 31, 1999, in conformity
with accounting principles generally accepted in the United States.

/s/ ERNST & YOUNG LLP

Palo Alto, California
January 20, 2000

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31

COR THERAPEUTICS, INC.

BALANCE SHEETS
(in thousands, except per share data)

December 31,
-----------------------
1999 1998
--------- ---------

ASSETS

Current assets:
Cash and cash equivalents $ 12,780 $ 10,532
Short-term investments 32,973 64,673
Contract receivables 5,751 2,398
Prepaid copromotion expenses 30,747 19,236
Other current assets 791 817
--------- ---------
Total current assets 83,042 97,656

Property and equipment, net 4,855 5,437
--------- ---------
$ 87,897 $ 103,093
========= =========

LIABILITIES AND STOCKHOLDERS' EQUITY

Current liabilities:
Accounts payable $ 11,020 $ 6,268
Accrued compensation 4,525 4,516
Accrued development costs 1,768 4,005
Accrued copromotion costs 1,291 3,405
Deferred revenue 27,480 23,494
Other accrued liabilities 511 1,545
Capital lease obligations--current portion 1,621 2,003
--------- ---------
Total current liabilities 48,216 45,236
Capital lease obligations--noncurrent portion 2,925 3,261
Commitments and contingencies
Stockholders' equity:
Preferred stock, $.001 per share par value; 5,000 shares authorized -- --
Common stock, $.0001 per share par value; 40,000 shares
authorized; 25,249 and 24,431 shares issued and outstanding
at December 31, 1999 and December 31, 1998, respectively 3 2
Additional paid-in capital 252,163 244,937
Deferred compensation (176) (1,179)
Accumulated deficit (215,234) (189,164)
--------- ---------
Total stockholders' equity 36,756 54,596
--------- ---------
$ 87,897 $ 103,093
========= =========

See accompanying notes.

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32

COR THERAPEUTICS, INC.

STATEMENTS OF OPERATIONS
(in thousands, except per share amounts)

Year Ended
December 31,
----------------------------------
1999 1998 1997
-------- -------- --------

Contract revenues:
Copromotion revenue $ 34,132 $ 3,933 $ --
Milestone revenue 12,000 32,000 8,000
Development and other contract revenue 10,526 6,030 14,190
-------- -------- --------
Total contract revenues 56,658 41,963 22,190
-------- -------- --------

Expenses:
Cost of copromotion revenue 22,471 11,803 --
Research and development 36,563 39,915 47,831
Marketing, general and administrative 26,018 21,474 10,067
-------- -------- --------
Total expenses 85,052 73,192 57,898
-------- -------- --------

Loss from operations (28,394) (31,229) (35,708)

Interest income 2,953 4,342 2,840
Interest expense (629) (727) (624)
-------- -------- --------

Net loss $(26,070) $(27,614) $(33,492)
======== ======== ========

Basic and diluted net loss per share $ (1.05) $ (1.14) $ (1.60)
======== ======== ========

Shares used in computing basic and diluted net loss per share 24,822 24,141 20,952
======== ======== ========

See accompanying notes.

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33

COR THERAPEUTICS, INC.

STATEMENTS OF STOCKHOLDERS' EQUITY
For the years ended December 31, 1999, 1998 and 1997
(in thousands)

Common Stock Additional Total
------------------ Paid-in Deferred Accumulated Stockholders'
Shares Par Value Capital Compensation Deficit Equity
------ --------- ---------- ------------ ----------- -------------

Balances at December 31, 1996 20,010 $2 $ 178,747 $ (249) $(128,058) $ 50,442
Issuance of common stock in a public offering
net of issuance costs of $4,459 3,335 - 58,906 -- -- 58,906
Issuance of common stock upon exercise
of stock options and pursuant to the
Employee Stock Purchase Plan 394 - 2,334 -- -- 2,334
Deferred compensation related to stock awards,
net of cancellations and amortization 28 - 439 (191) -- 248
Unrealized losses on available-for-sale
short-term investments -- - (40) -- -- (40)
Net loss -- - -- -- (33,492) (33,492)
------ -- --------- ------- --------- --------
Balances at December 31, 1997 23,767 2 240,386 (440) (161,550) 78,398
Issuance of common stock upon exercise
of stock options and pursuant to the
Employee Stock Purchase Plan 519 - 3,020 -- -- 3,020
Deferred compensation related to stock awards,
net of cancellations and amortization 145 - 1,361 (739) -- 622
Unrealized gains on available-for-sale
short-term investments -- - 170 -- -- 170
Net loss -- - -- -- (27,614) (27,614)
------ -- --------- ------- --------- --------
Balances at December 31, 1998 24,431 2 244,937 (1,179) (189,164) 54,596
Issuance of common stock upon exercise
of stock options and pursuant to the
Employee Stock Purchase Plan 823 1 7,133 -- -- 7,134
Deferred compensation related to stock awards,
net of cancellations and amortization
and other non-cash compensation (5) - 392 1,003 -- 1,395
Unrealized losses on available-for-sale
short-term investments -- - (299) -- -- (299)
Net loss -- - -- -- (26,070) (26,070)
------ -- --------- ------- --------- --------
Balances at December 31, 1999 25,249 $3 $ 252,163 $ (176) $(215,234) $ 36,756
====== == ========= ======= ========= ========

See accompanying notes.

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34

COR THERAPEUTICS, INC.

STATEMENTS OF CASH FLOWS
Increase (decrease) in cash and cash equivalents
(in thousands)

Year Ended
December 31,
-----------------------------------
1999 1998 1997
-------- --------- --------

Cash flows provided by (used in) operating activities:
Net loss $(26,070) $ (27,614) $(33,492)
Adjustments to reconcile net loss to net cash
used in operating activities:
Depreciation and amortization 2,120 3,358 3,545
Amortization of deferred compensation
and other non-cash compensation 1,395 622 248
Changes in assets and liabilities:
Contract receivables (3,353) (1,976) 7,222
Prepaid copromotion expenses (11,511) (12,814) (4,346)
Other current assets 26 (253) 780
Accounts payable 4,752 3,822 1,048
Accrued compensation 9 2,006 1,015
Accrued development costs (2,237) 850 (4,675)
Accrued copromotion costs (2,114) 2,149 1,256
Deferred revenue 3,986 22,608 (2,014)
Other accrued liabilities (1,034) 200 351
-------- --------- --------
Total adjustments (7,961) 20,572 4,430
-------- --------- --------
Net cash used in operating activities (34,031) (7,042) (29,062)
-------- --------- --------
Cash flows provided by (used in) investing activities:
Purchases of short-term investments (26,610) (104,124) (68,965)
Sales of short-term investments 46,067 21,551 51,584
Maturities of short-term investments 11,944 78,430 7,500
Additions to property and equipment (1,538) (3,387) (1,906)
-------- --------- --------
Net cash provided by (used in) investing activities 29,863 (7,530) (11,787)
-------- --------- --------
Cash flows provided by (used in) financing activities:
Proceeds from capital lease obligations 1,418 2,684 1,944
Repayment of capital lease obligations (2,136) (2,809) (2,741)
Issuance of common stock 7,134 3,020 61,240
-------- --------- --------
Net cash provided by financing activities 6,416 2,895 60,443
-------- --------- --------
Net increase (decrease) in cash and cash equivalents 2,248 (11,677) 19,594
Cash and cash equivalents at the beginning of the year 10,532 22,209 2,615
-------- --------- --------
Cash and cash equivalents at the end of the year $ 12,780 $ 10,532 $ 22,209
======== ========= ========

Supplemental schedule of non-cash financing activities:
Cash paid during the period for interest $ 629 $ 727 $ 624
======== ========= ========

See accompanying notes.

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35

NOTES TO FINANCIAL STATEMENTS

1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

COR Therapeutics, Inc. ("COR" or the "Company") was incorporated in Delaware on
February 4, 1988. COR is dedicated to the discovery, development and
commercialization of novel pharmaceutical products to establish new standards of
care for the treatment and prevention of severe cardiovascular diseases.
INTEGRILIN(R) (eptifibatide) Injection is the first product that COR has taken
from discovery to commercialization. Approved by the U.S. FDA in May 1998,
INTEGRILIN is indicated for the treatment of patients with an acute coronary
syndrome and patients who undergo angioplasty procedures.

Cash, investments and credit risk

The Company considers all highly liquid investments with an original maturity of
three months or less from the date of purchase to be cash equivalents. The
Company is exposed to interest rate risk on the investments of its excess cash.
The primary objective of the Company's investment activities is to preserve
principal while at the same time maximizing yields without significantly
increasing risk. To achieve this objective, the Company invests in highly liquid
and high quality debt securities. To minimize the exposure due to adverse shifts
in interest rates, the Company invests in short-term securities with maturities
of less than three years.

Securities available-for-sale

Management determines the appropriate classification of debt securities at the
time of purchase and re-evaluates such designation as of each balance sheet
date. Debt securities have been classified as available-for-sale.
Available-for-sale securities are carried at fair value, with the unrealized
gains and losses reported in a separate component of stockholders' equity. The
amortized cost of debt securities in this category is adjusted for amortization
of premiums and accretion of discounts to maturity. Such amortization is
included in interest income. Realized gains and losses and declines in value
judged to be other than temporary on available-for-sale securities are included
in interest income. The cost of securities sold is based on the specific
identification method. Interest and dividends on securities classified as
available-for-sale are included in interest income.

Property and equipment

Property and equipment is stated at cost and depreciated over the estimated
useful lives of the assets, generally three to four years, using the
straight-line method. Assets under capitalized leases are amortized over the
shorter of the lease term or life of the asset. Property and equipment consists
of the following (in thousands):

December 31,
---------------------
1999 1998
-------- --------

Machinery and equipment $ 14,169 $ 14,935
Office furniture and fixtures 1,061 974
Leasehold improvements 10,212 10,204
-------- --------
25,442 26,113
Less accumulated depreciation and amortization (20,587) (20,676)
-------- --------
Property and equipment, net $ 4,855 $ 5,437
======== ========

Contract revenues

Contract revenues include copromotion revenue, milestone revenue, and
development and other contract revenue. Milestone revenue and development and
other contract revenue is recorded as earned based on the performance
requirements of the contract, while related costs are expensed as incurred.
Other contract revenue includes recognition of reimbursement to COR by
Schering-Plough Ltd. and Schering Corporation (collectively, "Schering")

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36

of certain manufacturing-related expenses for materials used outside copromotion
territories when the reimbursement is realizable and earned. Copromotion revenue
is generally recognized at the time of shipment of the related product by
Schering to wholesalers and is recorded net of allowances, if any, that
management believes are sufficient to cover future requirements.

Copromotion revenue includes the Company's share of profits, as defined in the
agreement with Schering, from the sales of INTEGRILIN(R) (eptifibatide)
Injection by Schering, as well as the reimbursement from Schering of the
Company's costs of copromotion revenue, which includes certain
manufacturing-related and marketing expenses. Certain manufacturing-related
expenses are deferred until the time of shipment of related product by Schering
to its customers inside and outside copromotion territories. Deferred revenue
includes payments from Schering received prior to the period in which the
related contract revenues are earned. To the extent that costs of copromotion
revenue from prior periods have not been reimbursed to the Company, Schering
will make reimbursements from future sales of INTEGRILIN, if any.

Prepaid copromotion expenses

Prepaid copromotion expenses represent materials on-hand, valued at cost, and
deposits associated with manufacturing-related copromotion expenses. Prepaid
copromotion expenses consist of the following (in thousands):

December 31,
---------------------
1999 1998
------- -------

Deposits and prepayments $ 5,626 $10,637
Bulk materials 13,169 6,900
Finished goods 11,952 1,699
------- -------
$30,747 $19,236
======= =======

Concentration

The Company and Schering copromote one product, INTEGRILIN, in the United
States. The Company has established long-term supply arrangements with two
suppliers for the bulk product and with another two suppliers for the filling
and final packaging of INTEGRILIN.

Net loss per share

In accordance with Financial Accounting Standards Board Statement of Financial
Accounting Standards No. 128, "Earnings Per Share" ("SFAS No. 128"), basic and
diluted net loss per share has been computed using the weighted average number
of shares of Common Stock outstanding during the period. Had the Company been in
a net income position, diluted earnings per share would have included the shares
used in the computation of basic net income per share as well as the impact of
outstanding options to purchase an additional 1,385,000, 1,016,000 and 1,220,000
shares for the years ended December 31, 1999, 1998 and 1997 respectively. The
impact of such outstanding stock options has been excluded because they are
anti-dilutive for all periods presented.

Advertising and promotion costs

Advertising and promotion costs are expensed in the period they are incurred.
Advertising and promotion costs totaled $10,702,000 in 1999, $9,634,000 in 1998,
and $2,127,000 in 1997.

Use of estimates

The preparation of financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the amounts reported in the financial statements and accompanying notes.
Actual results could differ from those estimates.

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37

Accounting for stock-based compensation

The Company has elected to follow Accounting Principles Board Opinion No. 25,
"Accounting for Stock Issued to Employees" ("APB 25") and related
Interpretations in accounting for its employee stock options because, as
discussed in Note 5 below, the alternative fair value accounting provided for
under Statement of Financial Accounting Standards No. 123, "Accounting for
Stock-Based Compensation" ("SFAS No. 123"), requires the use of option valuation
models that were not developed for use in valuing employee stock options. Under
APB 25, because the exercise price of the Company's employee stock options
equals the market price of the underlying stock on the date of grant, no
compensation expense is recognized.

Reclassification

The Company has reclassified certain prior year balances to conform to current
year presentation.

Comprehensive loss

In 1998, the Company adopted Statement of Financial Accounting Standards No.
130, "Reporting Comprehensive Income" ("SFAS No. 130"). SFAS No. 130 requires
unrealized gains and losses on the Company's available-for-sale securities to be
included in other comprehensive income. In 1999, 1998 and 1997 unrealized gains
or losses were not material and total comprehensive loss closely approximated
net loss in each fiscal year.

Segment information

The Company applies Statement of Financial Accounting Standards No. 131,
"Disclosures about Segments of an Enterprise and Related Information" ("SFAS No.
131"). SFAS No. 131 establishes standards for the way that public business
enterprises report information about operating segments in annual financial
statements and requires that those enterprises report selected information about
operating segments in interim financial reports. SFAS No. 131 also establishes
standards for related disclosures about products and services, geographic areas
and major customers.

The Company's business activities include the discovery, development and
commercialization of novel cardiovascular pharmaceutical products and have been
organized into one operating segment. All of the Company's operating assets are
located in the United States. All of the Company's revenues are derived from
within the United States, except for royalty revenue earned on sales of
INTEGRILIN(R) (eptifibatide) Injection by Schering outside of the United States.

Recent accounting pronouncements

In June 1998, the Financial Accounting Standards Board issued Statement of
Financial Accounting Standards No. 133, "Accounting for Derivative Instruments
and Hedging Activities" ("SFAS No. 133"). SFAS No. 133 requires the Company to
recognize all derivatives on the balance sheet at fair value. Derivatives that
are not hedges must be adjusted to fair value through net income. SFAS No. 133
is effective for the Company's year ending December 31, 2001. COR does not
currently hold any derivatives and does not anticipate holding any derivatives
in the future. Accordingly, the Company does not expect this pronouncement to
materially impact results of future operations.

In December 1999, the Securities and Exchange Commission issued Staff Accounting
Bulletin No. 101, "Revenue Recognition in Financial Statements" ("SAB 101"). SAB
101 summarizes certain areas of the Staff's views in applying generally accepted
accounting principles to revenue in financial statements and specifically
addresses revenue recognition for non-refundable up-front fees received in
connection with collaboration agreements. The Company is currently evaluating
the impact of SAB 101 on its revenue recognition policy related to up-front fees
received from Schering.

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COLLABORATION AGREEMENTS

Collaboration agreement with Schering-Plough Ltd. and Schering Corporation

In April 1995, the Company entered into a collaboration agreement with Schering
to jointly develop and commercialize INTEGRILIN(R) (eptifibatide) Injection on a
worldwide basis. During the past three years, the Company has recognized
contract revenues under the agreement as follows (in thousands):

1999 1998 1997
------- ------- -------

Milestone revenue in 1999 consists of $12,000,000 from Schering related to the
marketing authorization granted to INTEGRILIN in the European Union (EU) for
certain indications. Milestone revenue in 1998 includes $24,000,000 from
Schering in connection with regulatory approval of INTEGRILIN in the United
States and $8,000,000 from Schering in connection with the application for
regulatory approval of INTEGRILIN in the EU. Milestone revenue in 1997 includes
$8,000,000 from Schering in connection with the completion of PURSUIT, a large
Phase III clinical trial for INTEGRILIN.

The Company and Schering co-promote the drug in the United States and share any
profits or losses. Schering is responsible for the distribution of the final
product from manufacturers to wholesalers. Outside of the United States,
Schering markets INTEGRILIN as our exclusive licensee on a royalty-bearing
basis. The Company has the right in the future to co-promote the product in
Europe and Canada and share any profits or losses. In the United States, the
exact profit-sharing ratio between the companies depends on the amount of sales
effort contributed by each company. Schering is primarily responsible for
regulatory filings outside the United States and Canada. Schering participates
in and shares the costs of continuing development of INTEGRILIN. Under the terms
of the agreement, both parties have certain rights to terminate for breach. In
December 1998 and November 1999, the Company amended its agreement with
Schering. The November 1999 amendment extended the period during which Schering
has exclusive rights to market INTEGRILIN in Europe, added a period of marketing
exclusivity for Schering in Canada, and increased the royalty opportunities
payable to us during the period of Schering's exclusivity.

Collaboration agreement with Kyowa Hakko Kogyo Co., Ltd.

In November 1992, we entered into a collaboration agreement with Kyowa Hakko
Kogyo Co., Ltd. focused on the discovery and development of small molecule
pharmaceuticals, primarily for the prevention of restenosis following
angioplasty. The research term of our collaboration expired in November 1999 in
accordance with the terms of that agreement. COR plans to continue this research
program. COR and Kyowa Hakko both have specific development and marketing rights
for any products resulting from the collaboration. In addition, under the terms
of the agreement, Kyowa Hakko has certain rights to supply bulk material for the
manufacture of any products resulting from the collaboration, and we have agreed
to purchase our requirements for such material from Kyowa Hakko.

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39

FINANCIAL INSTRUMENTS

The following methods and assumptions were used by the Company in estimating its
fair value disclosures for financial instruments:

Cash and cash equivalents: The carrying amount of cash and cash equivalents
reported on the balance sheet approximates its fair value.

Short-term investments: Short-term investments consist of marketable debt
securities and are classified as available-for-sale. These investments are
carried at fair value and any unrealized gains and losses are reported in a
separate component of stockholders' equity. The fair values are based upon
quoted market prices.

At December 31, 1999, short-term investments were as follows (in thousands):

Amortized Unrealized Unrealized Estimated
Cost Gains Losses Fair Value
--------- ---------- ---------- ----------

U. S. government securities $15,995 $ -- $ (53) $15,942
Corporate debt obligations 17,084 2 (55) 17,031
------- ----- -------- -------
$33,079 $ 2 $ (108) $32,973
======= ===== ======== =======

During the year ended December 31, 1999, the Company sold short-term investments
with a fair value of $46,067,000, resulting in gross realized gains of $50,000
and gross realized losses of $15,000.

The amortized cost and estimated fair value of short-term investments at
December 31, 1999, classified by contractual maturity, were as follows (in
thousands):

Amortized Estimated
Cost Fair Value
-------- ----------

Due in one year or less $30,559 $30,481
Due after one year and in less than
three years 2,520 2,492
------- -------
$33,079 $32,973
======= =======

At December 31, 1998, short-term investments were as follows (in thousands):

Amortized Unrealized Unrealized Estimated
Cost Gains Losses Fair Value
--------- ---------- ---------- ----------

U. S. government securities $22,793 $ 116 $ (1) $22,908
Corporate debt obligations 41,683 89 (7) 41,765
------- ----- -------- -------
$64,476 $ 205 $ (8) $64,673
======= ===== ======== =======

During the years ended December 31, 1998 and 1997, the Company sold short-term
investments with a fair value of $21,551,000 and $51,584,000, resulting in gross
realized gains of $44,000 and $38,000 and gross realized losses of $22,000 and
$86,000, respectively.

Long and short-term debt: The carrying amounts of the Company's borrowings under
its secured debt agreements approximate their fair values. The fair values are
estimated using a discounted cash flow analysis based on the Company's current
incremental borrowing rates for similar types of borrowing arrangements.

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40

LEASE OBLIGATIONS

The Company leases office and laboratory facilities and equipment. Rent expense
for operating leases was approximately $2,965,000 in 1999, $2,521,000 in 1998,
and $1,656,000 in 1997. Future minimum lease payments under non-cancelable
leases are as follows (in thousands):

Capital Operating
Leases Leases
------- ---------

2000 $ 1,953 $ 2,501
2001 1,470 2,323
2002 1,327 2,416
2003 438 2,512
2004 -- 2,164
------- -------
Total minimum lease payments 5,188 $11,916
=======
Less amount representing interest (642)
-------
Present value of future lease payments 4,546
Less current portion (1,621)
-------
Noncurrent portion of capital lease obligations $ 2,925
=======

The aggregate and net values of property and equipment under capital lease are
as follows (in thousands):

December 31,
-------------------
1999 1998
------- -------

Aggregate value of assets under capital lease $ 7,671 $ 9,475
Accumulated amortization (4,484) (5,535)
------- -------
Net value of assets under capital lease $ 3,187 $ 3,940
======= =======

5. STOCKHOLDERS' EQUITY

Stock option plans

In 1988, the Company adopted the 1988 Employee Stock Option Plan and the 1988
Consultant Stock Option Plan (collectively, the "1988 Plans"). Under these
plans, the Company granted both incentive and non-qualified stock options to
employees and consultants. The exercise prices were set at no less than the fair
market value of the Company's stock on the date of grant and the options became
exercisable based upon the individual terms of the grant.

In 1991, the Company terminated the 1988 Plans and adopted the 1991 Equity
Incentive Plan. Under this plan, the Company has granted (and continues to
grant) stock options and stock awards to employees and consultants. The exercise
prices are set at no less than the fair market value of the Company's stock on
the date of grant. The options generally vest over a period of 60 months and are
exercisable to the extent that they are vested.

In 1994, the Company adopted the 1994 Non-Employee Directors' Stock Option Plan.
Under this plan, as amended, the Company grants non-qualified options to Board
members who are neither employees nor consultants to the Company. The exercise
prices are set at no less than the fair market value of the Company's stock on
the date of grant and the options become exercisable based upon the individual
terms of the grant.

In 1998, the Company adopted the 1998 Non-Officer Equity Incentive Plan. Under
this plan, the Company may grant non-qualified stock options and stock awards to
employees who are not officers of the Company. The exercise prices are set at no
less than the fair market value of the Company's stock on the date of grant and
the options become exercisable based upon the individual terms of the grant.

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41

During the past three years, options under these plans were vested and
exercisable as follows:

December 31,
-------------------------------------------
1999 1998 1997
----------- ----------- -----------

Exercisable Shares
1988 Employee Stock Option Plan 194,452 309,270 499,156
1988 Consultant Stock Option Plan 20,000 59,167 72,167
1991 Equity Incentive Plan 2,458,322 2,193,974 1,766,526
1994 Non-Employee Directors' Stock Option Plan 155,000 84,166 83,749
1998 Non-Officer Equity Incentive Plan 110,771 37,635 --
----------- ----------- -----------
2,938,545 2,684,212 2,421,598
=========== =========== ===========
Aggregate Exercise Price
1988 Employee Stock Option Plan $ 273,000 $ 338,000 $ 410,000
1988 Consultant Stock Option Plan 12,000 24,000 28,000
1991 Equity Incentive Plan 30,042,000 26,926,000 21,767,000
1994 Non-Employee Directors' Stock Option Plan 1,876,000 1,209,000 1,238,000
1998 Non-Officer Equity Incentive Plan 1,510,000 545,000 --
----------- ----------- -----------
$33,713,000 $29,042,000 $23,443,000
=========== =========== ===========

During the past three years, activity under these plans was as follows:

Options Outstanding
--------------------------
Weighted
Shares Average
Available Number of Exercise
for Grant Shares Price
---------- ---------- --------

Balance at December 31, 1996 1,171,050 3,888,635 $ 9.45
Stock awards, net of forfeitures (28,296) -- --
Additional shares authorized 600,000 -- --
Options granted (1,046,750) 1,046,750 13.24
Options forfeited 217,932 (217,932) 11.34
Options exercised -- (304,922) 5.23
---------- ----------
Balance at December 31, 1997 913,936 4,412,531 10.64
Stock awards, net of forfeitures (161,941) -- --
Additional shares authorized 450,000 -- --
Options granted (731,750) 731,750 13.56
Options forfeited 223,596 (223,596) 13.04
Options exercised -- (320,579) 4.39
---------- ----------
Balance at December 31, 1998 693,841 4,600,106 11.40
Stock awards, net of forfeitures 6,101 -- --
Additional shares authorized 400,000 -- --
Options granted (802,600) 802,600 12.56
Options forfeited 216,566 (216,566) 13.27
Options exercised -- (641,121) 8.34
---------- ----------
Balance at December 31, 1999 513,908 4,545,019 11.95
========== ==========

The Company provided deferred compensation related to stock awards of $100,000,
$1,397,000, and $439,000 and reversed deferred compensation related to stock
award forfeitures of $131,000, $36,000 and $0 in 1999, 1998 and 1997
respectively. The Company amortized deferred compensation expense of $972,000 in
1999, $622,000 in 1998, and $248,000 in 1997. In connection with the extension
of the term of the option agreement of certain optionees, the Company recorded
$423,000 of non-cash compensation expense in 1999.

40
42

The weighted-average grant-date fair value of options granted was $10.45 in
1999, $10.51 in 1998, and $9.84 in 1997.

The following table summarizes information about stock options outstanding at
December 31, 1999:

Weighted
Average Weighted
Number of Remaining Average Number of Weighted
Range of Options Contractual Exercise Options Average
Exercise Prices Outstanding Life (years) Price Exercisable Exercise Price
- ---------------- ----------- ------------ --------- ----------- --------------

$ 0.30 - $ 8.88 560,097 4.56 $ 5.82 505,720 $ 5.53
$ 9.06 - $11.19 1,411,097 7.18 10.35 688,828 10.42
$11.38 - $12.50 967,826 4.78 12.23 885,346 12.22
$12.75 - $15.31 925,699 5.97 13.75 546,679 14.12
$15.38 - $21.06 680,300 7.61 17.44 311,972 16.68
--------------- --------- ---------
$ 0.30 - $21.06 4,545,019 6.16 11.95 2,938,545 11.47
=============== ========= =========

Stock purchase plan

In 1991, the Company adopted the 1991 Employee Stock Purchase Plan. Under this
plan, full-time employees may contribute up to 15% of their compensation to
purchase Common Stock at 85% of its fair market value on specified dates. As of
December 31, 1999, 365,422 shares remain authorized for issuance under the stock
purchase plan.
During the past three years, the Company has issued Common Stock under the stock
purchase plan as follows:

Shares Range
For the year ended Issued of Prices
------------------ ------- --------------

December 31, 1999 181,867 $8.55 - $12.33
December 31, 1998 182,428 $6.22 - $17.56
December 31, 1997 88,383 $7.28 - $ 9.03

Pro forma information

The Company has elected to follow APB 25 and related Interpretations in
accounting for employee stock options (see Note 1, "Summary of significant
accounting policies"). Under APB 25, the Company does not recognize any
compensation expense related to the grants of stock options because the exercise
price of the Company's stock options is equal to the fair market value of the
Company's stock on the date of grant.

Pro forma information regarding net loss and net loss per share is required by
SFAS No. 123. The Company has used the fair value method described in SFAS No.
123 to determine this pro forma information for all employee stock options
granted after December 31, 1994. The fair value method was also applied to
shares acquired through the Company's stock purchase plan which, for the
purposes of this disclosure, the Company has treated as employee stock options.
The fair value of the Company's employee stock options was estimated at the date
of grant and/or purchase using the Black-Scholes option-pricing model.

During the past three years, the Company has used the following weighted average
assumptions in the Black-Scholes model:

1999 1998 1997
----- ----- -----

Risk-free interest rate 5.44% 5.23% 6.21%
Dividends None None None
Volatility 0.77 0.77 0.69
Expected life 5 yrs 5 yrs 5 yrs

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43

The Black-Scholes model was developed to estimate the fair value of traded
options. Traded options, however, have no vesting restrictions and are fully
transferable. Additionally, the model requires the input of highly subjective
assumptions. Because the Company's employee stock options have characteristics
significantly different from traded options and because slight changes in the
input assumptions can materially affect the fair value estimate, the Company
does not believe that the Black-Scholes model provides a reliable measure of the
fair value of the Company's employee stock options. Additionally, the effects of
applying SFAS No. 123 for the recognition of compensation expense and provision
of pro forma disclosures in 1999, 1998 and 1997 are not likely to be
representative of the effects on reported and pro forma net income in future
years because options vest over several years and additional awards may be made
in subsequent years.

Per SFAS No. 123, the Company has amortized the expense of the estimated fair
value over an option's vesting period. During the past three years, the
Company's pro forma expense has been as follows (in thousands except for the net
loss per share information):

For the Year Ended December 31,
----------------------------------
1999 1998 1997
-------- -------- --------

Net loss (as reported) $(26,070) $(27,614) $(33,492)
Basic and diluted net loss per share (as reported) $ (1.05) $ (1.14) $ (1.60)
Pro forma net loss $(33,887) $(35,223) $(39,677)
Pro forma basic and diluted net loss per share $ (1.37) $ (1.46) $ (1.89)

Common shares reserved for future issuance

At December 31, 1999, 5,424,349 shares of Common Stock were reserved for future
issuance under the stock option and stock purchase plans.

Preferred stock and anti-takeover provisions

In January 1995, the Company's Board of Directors adopted a Preferred Share
Purchase Rights Plan, commonly referred to as a "poison pill." The Company's
Certificate of Incorporation requires the approval of at least 66 2/3% of the
voting stock for certain transactions with or proposed by a holder of 15% or
more of the Company's voting stock. Pursuant to the Company's Certificate of
Incorporation, the Company's Board of Directors has the authority, without
further action of the stockholders, to issue up to 5,000,000 shares of preferred
stock in one or more series and to determine the price, rights, preferences and
privileges of those shares. The rights of holders of common stock will be
subject to the rights of the holders of any preferred stock that may be issued
in the future.

6. INCOME TAXES

At December 31, 1999, the Company had net operating loss carryforwards and
research and development tax credit carryforwards as follows (in thousands):

U.S. Federal California
------------ ----------

Net operating loss carryforwards $174,100 $20,800
Research and development tax credit carryforwards $ 4,800 $ 3,300

The federal net operating loss and research and development tax credit
carryforwards, if not utilized to offset taxable income in future periods,
expire between the years 2003 and 2019. The State of California net operating
loss carryforwards, if not utilized to offset taxable income in future periods,
expire between the years 2001 and 2004.

42
44

Because of the "change of ownership" provisions of the Tax Reform Act of 1986,
the Company's net operating loss and research and development tax credit
carryforwards may be subject to an annual limitation regarding utilization
against taxable income in future periods.

Significant components of the Company's deferred tax assets and liabilities for
federal and state income taxes at December 31, 1999 and 1998 were as follows (in
thousands):

December 31,
---------------------
1999 1998
-------- --------

Net operating loss carryforwards $ 60,400 $ 61,700
Capitalized research and development 8,400 9,500
Research and development credits 7,200 5,300
Deferred revenue 10,900 --
Other, net 6,800 5,300
-------- --------
Net deferred tax assets 93,700 81,800
Valuation allowance for deferred tax assets (93,700) (81,800)
-------- --------
$ -- $ --
======== ========

Because of the Company's lack of earnings history, the net deferred tax assets
have been fully offset by a valuation allowance. The valuation allowance
increased by $13,000,000 and $10,900,000 during the years ended December 31,
1998 and 1997, respectively.

7. CONTINGENCIES

In October 1997, a patent opposition was filed in Europe by another company
against the claims of a patent granted to the Company in Europe covering broad,
generic claims for INTEGRILIN(R) (eptifibatide) Injection, as well as numerous
related compounds that are not part of the Company's core technology. The
opposition asserts that all claims of the patent are unpatentable. The Company
intends to continue to vigorously defend its patent. However, this patent
opposition may result in an unfavorable outcome.

8. SUBSEQUENT EVENTS (UNAUDITED)

In January 2000, the Company authorized 1,300,000 additional common shares for
issuance under the Company's stock option plans, 900,000 of which are subject to
shareholder approval.

In February 2000 the Company completed a private placement of $300,000,000 5.0%
convertible subordinated notes due March 1, 2007 (the Notes). The Notes are
unsecured and subordinated in right of payment to all of our existing and future
senior debt and may be convertible under certain conditions. Interest on the
Notes is payable semi-annually on March 1 and September 1 of each year,
commencing September 1, 2000. The Notes may be converted by the note holders
into shares of COR common stock at a conversion rate of 14.8028 shares per
$1,000 principal amount of notes, which is equivalent to a conversion price of
$67.56 per share. The conversion rate is subject to adjustment in certain
events. The Company may redeem the Notes on or after March 1, 2003 and prior to
maturity, at a premium. The Company incurred issuance costs related to this
offering of approximately $11,000,000 (including aggregate underwriting
discounts and commissions) which we expect to amortize to interest expense over
the life of the Notes.

ITEM 9. CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
FINANCIAL DISCLOSURE

Not applicable.

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45

PART III

ITEM 10. DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT

IDENTIFICATION OF DIRECTORS

The information required by this Item concerning the Company's directors is
incorporated by reference from the sections captioned "Proposal 1: Election of
Directors" contained in the Company's Definitive Proxy Statement related to the
Annual Meeting of Stockholders to be held May 23, 2000, to be filed by the
Company with the Securities and Exchange Commission (the "Proxy Statement").

IDENTIFICATION OF EXECUTIVE OFFICERS

The information required by this Item concerning the Company's executive
officers is set forth in PART I, Item I of this Report.

SECTION 16(a) BENEFICIAL OWNERSHIP REPORTING COMPLIANCE

The information required by this Item is incorporated by reference from the
section captioned "Section 16(a) Beneficial Ownership Reporting Compliance"
contained in the Proxy Statement.

ITEM 11. EXECUTIVE COMPENSATION

The information required by this Item is incorporated by reference from the
section captioned "Executive Compensation" contained in the Proxy Statement.

ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

The information required by this Item is incorporated by reference from the
section captioned "Security Ownership of Certain Beneficial Owners and
Management" contained in the Proxy Statement.

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

The information required by this Item is incorporated by reference from the
sections captioned "Certain Transactions" and "Executive Compensation" contained
in the Proxy Statement.

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46

PART IV

ITEM 14. EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(A) 1. INDEX TO FINANCIAL STATEMENTS

Page in
Form 10-K
---------

Report of Ernst & Young LLP, Independent Auditors 29
Balance Sheets at December 31, 1999 and 1998 30
Statements of Operations for the years ended December 31, 1999, 1998 and 1997 31
Statements of Stockholders' Equity for the years ended December 31, 1999, 1998 and 1997 32
Statements of Cash Flows for the years ended December 31, 1999, 1998 and 1997 33
Notes to Financial Statements 34

2. All schedules are omitted because they are not applicable or not
required or because the required information is included in the
financial statements or notes thereto.

3. EXHIBITS

Number Exhibit
--------- --------------------------------------------------------

3.1(9) Restated Certificate of Incorporation of the Registrant.

3.2(2) By-laws of the Registrant.

4.1 Reference is made to Exhibits 3.1 and 3.2.

4.2(8) Registrant's Preferred Share Purchase Rights Agreement
between the Registrant and Chemical Trust Company of
California, dated as of January 23, 1995.

*10.1(2) Form of Indemnification Agreement between the Registrant
and its directors, executive officers and officers.

*10.2(2) Registrant's 1988 Employee Stock Option Plan and related
agreements.

*10.3(2) Registrant's 1988 Consultant Stock Option Plan and
related agreements.

++10.4(2) Research, Option and License Agreement between the
Registrant and Eli Lilly and Company, dated May 1, 1991.

10.5(2) Lease Agreement between the Registrant and NC Land
Associates Limited Partnership, dated September 23,
1988, as amended August 30, 1989 and Lease Rider, dated
September 23, 1988.

*10.6(1) Forms of option agreements used under the Registrant's
1991 Equity Incentive Plan.

*10.7(3) Form of offering document used under the Registrant's
1991 Employee Stock Purchase Plan.

++10.8(4) Collaboration Research Agreement between the Registrant
and Kyowa Hakko Kogyo, Co., Ltd., dated November 30,
1992.

++10.9(5) Collaboration Agreement between Eli Lilly and Company
and the Registrant, dated May 28, 1993.

++10.10(6) Collaboration Agreement between Ortho Pharmaceutical
Corporation and the Registrant, dated December 21, 1993.

*10.11(10) Registrant's 1994 Non-employee Directors' Stock Option
Plan, as amended.

*10.12(10) Registrant's 1991 Stock Purchase Plan, as amended.

*10.13(10) Registrant's 1991 Equity Incentive Plan, as amended.

++10.14(10) Amendment No. 1 to Collaboration Research Agreement
between the Registrant and Kyowa Hakko Kogyo Co., Ltd.,
dated May 9, 1994.

++10.15(8) Collaboration Agreement between Schering-Plough Ltd.,
Schering Corporation and the Registrant, dated April 10,
1995.

45
47

Number Exhibit
--------- --------------------------------------------------------

++10.16(10) Amendment No. 2 to Collaboration Research Agreement
between the Registrant and Kyowa Hakko Kogyo Co., Ltd.,
dated July 13, 1995.

++10.17(10) Amendment No. 3 to Collaboration Research Agreement
between the Registrant and Kyowa Hakko Kogyo Co., Ltd.,
dated August 1, 1995.

++10.18(9) Amendment No. 4 to Collaboration Research Agreement
between the Registrant and Kyowa Hakko Kogyo, Co., Ltd.,
dated November 10, 1995.

++10.19(10) Amendment No. 1 to Collaboration Research Agreement
between Ortho Pharmaceutical Corporation and the
Registrant, dated September 27, 1996.

++10.20(10) Amendment No. 1 to Collaboration Research Agreement
between Eli Lilly and Company and the Registrant, dated
November, 1996.

++10.21(10) Amendment No. 5 to Collaboration Research Agreement
between the Registrant and Kyowa Hakko Kogyo Co., Ltd.,
dated December 17, 1996.

*10.22(10) Description of Registrant's 1996 Incentive Pay Plan.

++10.23(11) Long Term Supply Agreement between Registrant and
Solvay, Societe Anonyme, dated September 28, 1995.

++10.24(11) Amendment No. 1 to the Long Term Supply Agreement
between Registrant and Solvay, Societe Anonyme, as
amended, dated April 1, 1997.

++10.25(11) License and Supply Agreement between the Registrant and
Solvay, Societe Anonyme, dated July 27, 1994.

++10.26(11) First Amendment to the License and Supply Agreement
between Registrant and Solvay, Societe Anonyme, as
amended, dated March 13, 1995.

++10.27(11) Second Amendment to the License and Supply Agreement
between Registrant and Solvay, Societe Anonyme, as
amended, dated June 1, 1995.

++10.28(11) Third Amendment to the License and Supply Agreement
between Registrant and Solvay, Societe Anonyme, as
amended, dated September 5, 1995.

++10.29(11) Letter Amendment to the License and Supply Agreement
between Registrant and Solvay, Societe Anonyme, as
amended, dated June 6, 1996.

++10.30(11) Fourth Amendment to the License and Supply Agreement
between Registrant and Solvay, Societe Anonyme, as
amended, dated April 1, 1997.

*10.31(12) 1998 Non-Officer Equity Incentive Plan.

*10.32(12) Form of Option Agreements used for the 1998 Non-Officer
Equity Incentive Plan.

++10.33(12) Amendment to Collaboration Agreement, dated December 23,
1998, between Schering-Plough Ltd. and Schering
Corporation and the Registrant.

*10.34(13) Key Employee Change in Control Severance Plan

+10.35 Second Amendment to Collaboration Agreement, dated
November 5, 1999, between Schering-Plough Ltd. and
Schering Corporation and the Registrant.

23.1 Consent of Ernst & Young LLP, Independent Auditors.

24.1 Power of Attorney, Reference is made to the signature
page.

27.1 Financial Data Schedule.

46
48

- --------------------------------------------------------------------------------

* Indicates management contracts or compensatory plans or
arrangements filed pursuant to Item 601(b)(10) of Regulation
S-K.

+ Confidential treatment requested.

++ Confidential treatment granted.

(1) Filed as an exhibit to the Registrant's Registration Statement
on Form S-8 (Reg. No. 33-42912) and incorporated herein by
reference.

(2) Filed as an exhibit to the Registrant's Registration Statement
on Form S-1 (Reg. No. 33-40627) or amendments thereto and
incorporated herein by reference.

(3) Filed as an exhibit to the Registrant's Registration Statement
on Form S-1 (Reg. No. 33-43181) or amendments thereto and
incorporated herein by reference.

(4) Filed as an exhibit to the Registrant's Annual Report on Form
10-K for the period ended December 31, 1992 and incorporated by
reference herein.

(5) Filed as an exhibit to the Registrant's Quarterly Report on Form
10-Q for the period ended June 30, 1993 and incorporated by
reference herein.

(6) Filed as an exhibit to the Registrant's Annual Report on Form
10-K for the period ended December 31, 1993 and incorporated by
reference herein.

(7) Filed as an exhibit to the Registrant's Annual Report on Form
10-K for the period ended December 31, 1994 and incorporated by
reference herein.

(8) Filed as an exhibit to the Registrant's Quarterly Report on Form
10-Q for the period ended June 30, 1995 and incorporated by
reference herein.

(9) Filed as an exhibit to the Registrant's Annual Report on Form
10-K for the period ended December 31, 1995 and incorporated by
reference herein.

(10) Filed as an exhibit to the Registrant's Annual Report on Form
10-K for the period ended December 31, 1996 and incorporated by
reference herein.

(11) Filed as an exhibit to the Registrant's Quarterly Report on Form
10-Q for the period ended September 30, 1998 and incorporated by
reference herein.

(12) Filed as an exhibit to the Registrant's Annual Report on Form
10-K for the period ended December 31, 1998 and incorporated by
reference herein.

(13) Filed as an exhibit to the Registrant's Quarterly Report on Form
10-Q for the period ended September 30, 1999 and incorporated by
reference herein.

(B) REPORTS ON FORM 8-K

There were no reports on Form 8-K filed for the quarter ended December
31, 1999.

47
49

SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Act of
1934, the Registrant has duly caused this Report to be signed on its behalf by
the undersigned, thereunto duly authorized, in the City of South San Francisco,
County of San Mateo, State of California, on the 24th day of March, 2000.

COR THERAPEUTICS, INC.

By /s/ PETER S. RODDY
-----------------------------------
Peter S. Roddy
Vice President, Finance
(Principal Accounting Officer)

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears
below constitutes and appoints Peter S. Roddy and Vaughn M. Kailian, and each of
them, as his true and lawful attorneys-in-fact and agents, with full power of
substitution for him, and in his name in any and all capacities, to sign any and
all amendments to this Report, and to file the same, with exhibits thereto and
other documents in connection therewith, with the Securities and Exchange
Commission, granting unto said attorneys-in-fact and agents, and each of them,
full power and authority to do and perform each and every act and thing
requisite and necessary to be done therewith, as fully to all intents and
purposes as he might or could do in person, hereby ratifying and confirming all
that said attorneys-in-fact and agents, and any of them or his substitute or
substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Exchange Act of 1934, this Report
has been signed below by the following persons on behalf of the Registrant and
in the capacities and on the dates indicated:

Signature Title Date
- ------------------------------------- ---------------------------------------------- --------------

/s/ VAUGHN M. KAILIAN President, Chief Executive Officer and March 24, 2000
- ------------------------------------- Director (Principal Executive and
Vaughn M. Kailian Financial Off Officer)
Officer)

/s/ CHARLES J. HOMCY Executive Vice President, Research and March 24, 2000
- ------------------------------------- Development and Director
Charles J. Homcy

/s/ PETER S. RODDY Vice President, Finance (Principal Accounting March 24, 2000
- ------------------------------------- Officer)
Peter S. Roddy

/s/ SHAUN R. COUGHLIN Director March 24, 2000
- -------------------------------------
Shaun R. Coughlin

/s/ JAMES T. DOLUISIO Director March 24, 2000
- -------------------------------------
James T. Doluisio

/s/ JERRY T. JACKSON Director March 24, 2000
- -------------------------------------
Jerry T. Jackson

/s/ ERNEST MARIO Director March 24, 2000
- -------------------------------------
Ernest Mario

/s/ ROBERT R. MOMSEN Director March 24, 2000
- -------------------------------------
Robert R. Momsen

/s/ LLOYD HOLLINGSWORTH SMITH, JR. Director March 24, 2000
- -------------------------------------
Lloyd Hollingsworth Smith, Jr.

EXHIBIT INDEX