BioWorld International Correspondent

LONDON - British Biotech plc agreed to collaborate on its anti-infectives program with privately held GeneSoft Inc. for an initial payment of US$4 million, with a further $1 million and an equity stake in GeneSoft to come in October, when the lead candidate BB-83689 enters Phase I.

Elliot Goldstein, CEO of British Biotech, said the deal achieved the key objectives of expanding the company's antibiotics program while sharing costs and commercialization rights.

"GeneSoft is an ideal partner for the program," he said. "It specializes in antibiotic drug discovery and development and brings a wealth of clinical and scientific expertise in this field."

The deal covers the development and commercialization of BB-83698 - a peptide deformylase (PDF) inhibitor - for the treatment of pneumonia, the lead optimization and clinical development of further oral PDF inhibitors discovered by British Biotech, and the attempt to discover further drugs against other bacteria, using British Biotech metalloenzyme targets.

BB-83698 would be the first of a new class of antibiotics to reach the clinic. The partners will share development costs and would split profits equally. The PDF inhibitor collaboration, to run for three years initially, will involve Oxford-based British Biotech maintaining its contribution to the program at current levels while GeneSoft, of South San Francisco, adds resources equivalent to 170 percent of British Biotech's.

Bacteria produce a number of metalloenzymes, several of which are believed to be essential to survival, and PDF is a recognized target for antibiotics. The PDF enzyme is essential for bacterial growth, and the gene-encoding PDF is present in all bacterial genomes sequenced to date. In preclinical studies, British Biotech's PDF inhibitors have shown they are suitable for treating respiratory tract infections and have a high potency against antibiotic-resistant pathogens. As part of the UK government's biodefense initiative, government scientists are investigating the use of certain British Biotech metalloenzyme inhibitors against anthrax and botulism.

In another announcement, British Biotech said treatment began in a second Phase I trial of BB-10901 in small-cell lung cancer. The drug, being developed in collaboration with ImmunoGen Inc., of Cambridge, Mass., is a conjugate of the humanized monoclonal antibody hu901, which binds to the CD56 antigen found on the surface of certain tumor cells, with the cytotoxic DM1.