Shaman Reports Positive Study Results for Virend; Plant-derived herpes treatment shows promise in Phase II trial.

Shaman Pharmaceuticals Inc. (NASDAQ:SHMN) today announced that Virend, its plant-derived anti-viral drug, was shown to be efficacious in healing herpes lesions in a Phase II clinical trial.

Results from the randomized, double-blinded, placebo-controlled study showed that 38 percent of patients receiving Virend had lesions that healed completely vs. 14 percent in the placebo-controlled group. The study involved 45 patients with AIDS and recurring genital herpes.

"We are thrilled by these results," said Shaman President and Chief Executive Officer, Lisa A. Conte. "This study clearly supports Virend's efficacy and spurs us to move forward. Based on these results, Shaman has begun planning a pivotal Phase III study in patients with genital herpes," she said.

Virend, which is a topical formulation of the compound SP-303, is derived from a plant that for generations has been used in South America to treat herpes lesions, as well as a host of other medical conditions. Genital herpes affects more than 30 million people worldwide, with 500,000 new cases diagnosed each year.

Currently, oral Aciclovir is the only approved treatment for recurrent herpes lesions. In 1994, Aciclovir's sales were estimated to be in excess of $1.4 billion.

The trial was designed to assess Virend's effectiveness in healing the lesions of patients with recurrent genital herpes and acquired immunodeficiency syndrome. Participants had similar medical histories and self-administered their treatment topically -- either Virend (24 patients) or placebo (21 patients) -- three times a day for 21 days. Compliance was judged to be excellent, treatments appeared to be well tolerated, and no clinically significant side-effects were noted.

"These patients were very ill and treatment with Virend healed the lesions of many of these patients," said Richard Whitely, M.D., Professor of Pediatrics, Microbiology and Medicine at the University of Alabama and a leading herpes expert. "Many individuals with recurrent herpes lesions desire topical formulations of therapy rather than continuously taking oral antiviral medications."

At the close of the study, all patients were given the option to receive Virend for an additional 21 days. Seventeen patients elected further treatment, including eight from the placebo group. Of these 17 patients, eight were completely healed, further supporting the efficacy of Virend.

G. Kirk Raab, Chairman of Shaman's Board of Directors, said, "These dramatic results will bring greater visibility to our successful ethnobotanical approach to drug discovery."

Shaman Pharmaceuticals is applying an integrated approach to discover new chemical entities from tropical plants with a history of medicinal use. Shaman relies on ethnomedical investigation and sophisticated screening models, which result in a more efficient drug discovery process. Shaman's diabetes program, which embodies this approach, has resulted in the discovery of multiple new chemical entities and forms the basis for a collaborative relationship with Ono Pharmaceuticals Inc.

In addition to Virend, Shaman has two other products in development: Provir, an oral treatment for secretory diarrhea, currently in Phase II trials; and Nikkomycin-Z, an oral anti-fungal for the treatment of endemic mycosis, which is in late pre-clinical development. -0-

Note to Editors: Virend(TM) and Provir(TM) are trademarks of Shaman Pharmaceuticals Inc.

CONTACT: Shaman Pharmaceuticals Inc.

Kurt E. Amundson, 415/952-7070, ext. 464

Julie Wood, 415/952-7070, ext. 481