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EXHIBIT 99.21
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Contact:          Jerry B. Hook, Ph.D.
                  President & Chief Executive Officer
                  Sparta Pharmaceuticals, Inc.
                  (215) 442-1700, Ext. 205

FOR IMMEDIATE RELEASE


  Sparta Pharmaceuticals, Inc. Announces Patent Approval From The United States
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                           Patent and Trademark Office
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         Horsham, PA, October 17, 1997, Sparta Pharmaceuticals, Inc. (NASDAQ:
SPTA, SPTAU, SPTAW, SPTAZ AND SPTAL) announced that the United States Patent and
Trademark Office has granted United States Patent #5,674,708 submitted by Dr.
Harvey Rubin and colleagues of The University of Pennsylvania (Penn). The patent
is entitled, "[alpha]-1- Antichymotrypsin Analogues Having Elastase Inhibitory
Activity". This is the seventh United States patent to be granted through
Sparta's collaboration with Penn.

Through a Sparta-funded grant, Dr. Rubin, who is a scientific advisor to the
Company, has created a new class of recombinant modified human proteins that are
specific serine protease inhibitors. The lead compound of this series, LEX 032,
functions to inhibit acute, life-threatening inflammation. Sparta believes this
product may have utility in acute pulmonary inflammation and reperfusion injury
such as thrombo-embolic stroke. The Company was recently awarded a Phase II SBIR
grant to support more detailed investigations with this compound in stroke.

According to Dr. Jerry B. Hook, Sparta's President and Chief Executive Officer,
"The issuance of this patent further strengthens our portfolio of compounds in
this promising area of therapeutics."

The Company believes this recombinant serine protease inhibitor program has the
potential to be successful in treating serious conditions where uncontrolled
inflammatory responses may have fatal consequences including cardiovascular
disorders, stroke, lung inflammation and pancreatitis. The Company has an
exclusive license to over sixty compounds covered in the seven U.S. patents
issued to Penn; international patents are pending.

This press release contains certain forward-looking statements within the
meaning of the "safe harbor" provisions of the Private Securities Litigation
Reform Act of 1995. Such statements are made based on management's current
expectations and beliefs, and actual results may vary from those currently
anticipated based upon a number of factors, including uncertainties inherent in
the drug development process, including clinical trials. The Company undertakes
no obligation to release publicly any revisions which may be made to reflect
events or circumstances after the date hereof.

Sparta is a development stage pharmaceutical company engaged in the business of
acquiring rights to, and developing for commercialization, technologies and
drugs for the treatment of a number of life threatening diseases including
cancer, cardiovascular disorders and inflammation. The Company has focused on
acquiring compounds that have been previously tested in humans and



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animals and technologies that may improve the delivery or targeting of
previously tested, and in some cases marketed, anticancer agents. Sparta's
foundation in cancer chemotherapy has been augmented by the addition of new
technology in the rapidly expanding field of serine protease inhibitors. Serine
protease inhibitors have wide applications in diverse fields such as
inflammation, reperfusion injury and stroke.

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