With the exception of CollaGenex Pharmaceuticals Inc.'s Periostat doxy-cycline for periodontal disease, matrix metalloproteinase inhibitors (MMPIs) have been disappointments. The latest setback came last week as Bayer Corp. halted all clinical development of its BAY 12-9566 MMPI. Nevertheless, other developers of MMPIs still say that their inhibitors will succeed where BAY 12-9566 has failed.

The Bayer compound, which was in Phase III testing to treat osteoarthritis and Phase II/III testing in various cancers, performed worse than placebo on time to progression and survival in an interim analysis of a small cell lung cancer trial that had enrolled 233 patients of a planned 700. Based on that outcome, Bayer discontinued development of the compound in all indications (see B10).