By Randall Osborne

BioCryst Pharmaceuticals Inc. has given up on the topical cream formulation of BCX-34 for cutaneous T cell lymphoma and psoriasis after Phase III trials brought results that are not statistically significant.

The company's stock (NASDAQ:BCRX) plummeted, closing Friday at $6.25, down $3.25, a 34 percent drop.

Charles Bugg, BioCryst chairman and CEO, said the Birmingham, Ala.-based company is focused on an oral formulation of the drug. "We're pretty upbeat about it," he said. "Obviously the market is focusing heavily on [the topical formulation], but it's not the heart and soul of where we're going long-range."

Preliminary data from the lymphoma Phase III trial found a response rate of 28 percent in treated patients, hardly encouraging when compared with the placebo group's response rate of 24 percent. "We were aiming to get on the market next year [with the lymphoma application]," Bugg said.

Results from the psoriasis Phase III study showed a 14 percent greater improvement in mean lesion scores in the treated group over the placebo group, but the difference is not statistically significant.

BCX-34 is a small molecule that inhibits purine nucleoside phosphorylase, a human enzyme believed to be involved in the proliferation of T cells.

In Denmark, a Phase II clinical trial continues of BCX-34 topical ointment that delivers 15 to 20 times more of the drug than the failed topical cream.

Phase I/II trials are ongoing in the U.S. for an oral formulation for lymphoma and psoriasis. A Phase II control trial of oral BCX-34 for psoriasis and a Phase II/III trial for lymphoma are expected next year, Bugg said.

"That's been our major push," he said, adding that the topical cream was easier to move into Phase III. "You can get there quicker if you don't go into the bloodstream. We've had the oral program going as fast as it can go, and we don't believe the failure says anything at all about the potential of the oral drug."

Other Drugs Have Fallen Short Against Psoriasis

BioCryst joins many other drug companies that have tried to beat psoriasis, a chronic, recurrent disease characterized by inflammation and itching of welted, scaly skin. The mechanisms of autoimmune diseases such as psoriasis have proven more than challenging — especially when scientists seek to go beyond relieving symptoms and achieve a cure. (See BioWorld Financial Watch, Feb. 24, 1997, p. 1.)

The company also is conducting a Phase I feasibility study of an oral BCX-34 formulation for patients infected with HIV. "We're in dose-escalation trials," Bugg said. Early next year, BioCryst plans to begin Phase II/III trials for HIV.

BCX-34's promise against HIV represents a tricky approach to the killer disease. BCX-34 may function by taking away from the AIDS virus the activated CD4 T cells it infects and uses to replicate. When the drug is withdrawn, the important T cells return to pre-treatment levels. (See BioWorld Today, April 30, 1997, p. 1.)

BioCryst, founded in 1986, has $28 million cash. With a burn rate of about $1 million per month, "We have over two years' cash without going into any corporate partnering deals," Bugg said.

The company expects to collaborate on development of another product line: drugs that target neuraminidase, an enzyme required for the influenza virus to spread in the body. At the end of the second quarter of 1997, BioCryst recorded revenues of $1.427 million, with a net loss of $2.08 million.

BioCryst's prospects with topical BCX-34 against lymphoma and psoriasis seemed good two years after Phase II trials, but the company's fortunes dipped when an error was discovered in data analysis in the first part of the study. Data from the second part, however, which involved the same lymphoma patients, were enough to push the trials forward. *