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                                                             EXHIBIT 99.1

Contact:  Gwenetta B. Como
          Director, Investor Relations
          and Corporate Communications
          619/455-9800 x1184
          gwen_como@corvas.com

                                       
                        CORVAS ANNOUNCES TERMINATION OF
                  ORAL THROMBIN PROGRAM WITH SCHERING-PLOUGH
                                       
CORVAS AND SCHERING-PLOUGH'S TWO OTHER PROGRAMS, ORAL FACTOR XA INHIBITORS AND
                    HEPATITIS C INHIBITORS, REMAIN ON TRACK
                                       
SAN DIEGO, CA, August 14, 1998 - Corvas International Inc. (Nasdaq: CVAS) today
announced that after reviewing the results from a Phase I clinical trial,
Corvas and Schering-Plough Corporation (NYSE: SGP) have agreed to terminate
their oral thrombin inhibitors research and development collaboration. Corvas
and Schering-Plough have two additional programs in place, Factor Xa inhibitors
and Hepatitis C inhibitors, that are not affected by this decision.

Commenting on the news, Randall E. Woods, President and Chief Executive Officer
of Corvas, said, "The oral thrombin inhibitor was just one of several Corvas
drugs currently in clinical trials. While today's news is disappointing, Corvas
is pleased to continue our strong relationship with Schering-Plough with two
other programs and we remain excited about our other drugs in the clinic
including our proprietary anti-coagulant NAPc2 scheduled to enter Phase II
later this year and NIF (neutrophil inhibitory factor) being developed by
Pfizer Inc. for ischemic stroke."

George P. Vlasuk, Ph.D., Executive Vice-President of Research and Development
at Corvas stated, "Corvas remains committed to the full complement of programs
that constitute a broad-based R & D pipeline, including Factor Xa and Hepatitis
C inhibitors, novel vascular targeting strategies and several other research
programs focusing on protease inhibition."

To date, Corvas has received $17 million in equity and milestone payments from
Schering-Plough  and funding for the thrombin program through completion of the
R & D phase. Beginning in 1997, Schering-Plough assumed full financial and
developmental responsibility for the pre-clinical and clinical phases of the
program. Corvas continues to receive R & D funding from Schering-Plough for the
Factor Xa and Hepatitis C collaborations.

Corvas International, Inc. is a biopharmaceutical company engaged in the design
and development of a new generation of therapeutic agents in the fields of
blood clot formation (thrombosis), inflammation, cancer and other diseases.
Corvas has a strategic alliance with Pfizer Inc. to develop neutrophil
inhibitory factor (NIF) as a possible stroke therapy, and alliances with
Schering-Plough to develop an orally available Factor Xa inhibitor and an
inhibitor of a key protease associated with hepatitis C virus replication.
Corvas also holds an option to acquire Vascular Genomics, Inc. allowing it to
apply proteomics-and genomics-based technology to the human vasculature.

This press release may contain forward-looking statements within the meaning of
the Private Securities Litigation Reform Act of 1995. Actual results could vary
materially from those described in this press release as a result of a number
of factors. Meaningful factors that may affect these expected results include
the possibility that collaboration agreements may not be renewed or be
terminated with or without any product success, as well as risk factors listed
from time to time in the Company's SEC filings, including, but not limited to,
its 1997 Annual Report on Form 10-K and subsequent 10-Qs.

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