BioCryst Reports Favorable Results Of Phase II Open-Label CTCL Trial; Initiates Phase III Clinical Trial with Lead Compound.

BIRMINGHAM, Ala.--(BUSINESS WIRE)--September 27, 1995--BioCryst Pharmaceuticals, Inc. (Nasdaq: BCRX) today announced that results from a completed six-month open-label trial of its lead compound, BCX-34, showed evidence of efficacy for the topical treatment of cutaneous T-cell lymphoma (CTCL). The Company also announced the initiation of a multi-center Phase III clinical trial with a topical formulation of BCX- 34 for the treatment of CTCL.

The results of the open-label trial demonstrated favorable results in 18 (75 percent) of 24 patients with Stage I/IIA disease. Almost one-third (seven patients) had complete remissions, two additional patients were clinically clear of disease and nine patients showed partial remissions. The remaining six patients showed little or no improvement or got worse. The trial was performed at the University of Alabama at Birmingham (UAB) and Washington University in St. Louis. Based on these results, the Company has extended the open-label trial for another six months with 13 remaining patients. Interim results for this trial were presented in May at the annual meeting of the Society for Investigative Dermatology by W. Mitchell Sams, M.D., principal investigator and Chairman of Dermatology at UAB. The results of this open-label trial are not necessarily predictive of the outcomes of future trials for this indication.

"Over the course of the trial, the treatment demonstrated continued improvement of epidermal cancer lesions as well as a favorable long-term safety profile," said William J. Cook, M.D., Ph.D., Senior Vice President of Research & Development and Medical Director at BioCryst. "Of the nine patients who showed clinical clearance, four patients were clear by the second month of therapy, two more by the fourth month and three more by the sixth month. In addition, several patients who experienced clearance early on with the treatment have remained disease-free for more than five months now. The extension of the open-label study will give us useful safety and treatment data for BCX-34 over a consecutive 12-month period."

The recently-initiated Phase III double-blind, randomized, placebo-controlled trial will have two parallel patient groups, one receiving drug and the other receiving placebo. The trial will treat early-stage CTCL patients for six months with a one percent drug concentration while evaluating the primary clinical endpoints of complete and partial remissions. The trial will be administered by a contract research organization and will enroll 90 patients at eight U.S. centers, including Duke University, New York University, Northwestern University and UAB.

"Advancing our lead drug candidate into a pivotal trial for CTCL is a major step forward in our clinical program targeting T-cell cancers," said Charles E. Bugg, Ph.D., President and CEO of BioCryst. "Should we receive positive results from this trial, we will discuss with the FDA the possibility of preparing a New Drug Application requesting marketing clearance to treat CTCL."

CTCL is a form of cancer characterized by thick, scaly lesions on the skin which progress to ulcers and tumors of the lymph nodes and internal organs. CTCL affects an estimated 5,000-10,000 U.S. patients and the mean survival time after systemic progression of the disease is four years. Currently available therapies are either ineffective or have undesirable side effects.

In addition to CTCL, BioCryst is planning to conduct an expanded Phase II efficacy trial with topical BCX-34 for the treatment of psoriasis. The Company also plans to begin clinical trials with an oral formulation of BCX-34 to treat CTCL and T-cell leukemia. These diseases and others, such as rheumatoid arthritis and multiple sclerosis, are associated with an abnormal proliferation of T-cells. BCX- 34 is a potent small-molecule inhibitor of purine nucleoside phosphorylase (PNP), a human enzyme that plays a central role in the proliferation of T-cells. BCX-34 was granted Orphan Drug Status in October 1993 for CTCL, and qualifies for accelerated review as a new drug to treat serious and life-threatening illnesses.

Founded in 1986, BioCryst Pharmaceuticals, Inc. designs and develops novel small-molecule pharmaceuticals using structure-based drug design, an approach to drug discovery that integrates advanced biology, biophysics and medicinal chemistry. BioCryst is currently applying this approach to develop drug treatments for autoimmune and cardiovascular disorders and infectious diseases.

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