LONDON - SR Pharma plc released positive final results from a 28-patient trial of SRL172, its immune system potentiator, in the treatment of small-cell lung cancer.

Treatment with SRL172 in addition to standard chemotherapy resulted in a 49 percent survival benefit compared to chemotherapy alone. Survival was 12.9 months compared to 8.6 months, and the survival benefit was independent of the extent of the disease or the type of chemotherapy administered.

This second Phase II trial of SRL172 in lung cancer also provided further evidence that the compound, derived from a soil microorganism, is well tolerated and has a good safety profile.

The company, based in London, obtained positive results in an earlier Phase II study in non-small-cell lung cancer. Recruitment to a 400 patient European Phase III trial was completed last September. David Kennard, chief operating officer, said, "These latest results are very promising and further endorse our decision to proceed with the Phase III trial." If the results are positive the company expects to make a regulatory filing in the first quarter of 2001, with product marketing commencing early in 2002.

SR Pharma has decided to retain marketing rights in the UK. It said it is "actively assessing" its position in other European countries and is in discussion with a number of potential partners. The company had #10.5 million (US$16.8 million) cash at the end of 1999, which it said was sufficient to complete the clinical program in lung cancer and commence marketing, while continuing development in other indications. Third-party manufacturing capability is in place.

The Cancer Centre at the Royal Marsden Hospital in Kent, where the trials were carried out, now is running a 600-patient randomized small-cell lung cancer Phase II trial at its own expense to confirm its findings. Mary O'Brien, principle investigator, said findings to date "indicate that treatment with SRL172 improves the survival prospects for patients in a clinically meaningful way."

A 60-patient Phase II trial in renal cancer, to assess the impact of SRL172 monotherapy on disease progression, also has completed recruitment with results expected early in 2001.

SRL172 also is in Phase II in allergic asthma, and has been licensed to the Sakai Chemical Industry Co., of Tokyo, for the treatment of allergic disorders in Japan. The company is looking for a partner to develop and commercialize the product in allergic asthma in the U.S. and Europe.