CAMBRIDGE, U.K. — Chiroscience Group plc last week announced that its second-generation matrix metalloproteinase (MMP) inhibitor for cancer has entered Phase I trials. The company says that D2163 is more selective than first-generation MMP inhibitors, such as British Biotech's marimastat, which currently is in Phase III trials.

D2163 displayed "encouraging activity" in preclinical models of cancer without exhibiting activity associated with joint pain, the main side effect noted in clinical trials of marimastat.

Andy Richards, director of business development, told BioWorld International this was potentially a very significant development for Chiroscience. "The oncology market is fragmented. MMP inhibitors provide one of the few mechanisms that should produce drugs which address all solid tumors. Rather than being cytotoxic they suppress tumor growth and spread, and therefore have broad utility. They can be used over a longer period than chemotherapy, and thus represent a large market potential."

If Phase I is successful, Phase II is planned to commence late in 1998. Richards said it already has been decided what sort of patients will be in the trial, but declined to give details.

Unlike British Biotech, which is going at it alone on development of marimastat, Chiroscience plans to find a partner. "At some stage we will form a partnership with a major oncology player," said Richards. "It is difficult to say when. If we find a partner who has complementary views to us on clinical development, and we agree how to take it forward, we would do a deal earlier."

Richards does not believe the fate of D2163 is dependent on marimastat achieving registration. "They [British Biotech] have proved already that MMP inhibitors have an effect on a wide range of tumors."

While he acknowledged that Chiroscience has learned much from British Biotech's work on marimastat, he said, "We won't piggyback on this — our development program will be different."

Chiroscience, based in Cambridge, has another MMP inhibitor, D1927, developed in parallel with D2163, which should also begin Phase I this quarter.