Genta (GNTA, $7, down 27%) shares declined to a new 52-week low this week as the firm announced a filing delay for the regulatory approval of Genasense, an experimental antisense drug being tested in multiple cancer indications. At the recommendation of co-developer Aventis (AVE, $67, down 7%), patient numbers for a Phase III melanoma clinical trial will be expanded from 450 to 750. This action will delay the regulatory filing by several months to at least the middle of 2003. Patient counts in additional clinical trials for multiple myeloma and chronic lymphocytic leukemia may also be increased, causing delays in those studies as well.
While increasing the number of patients in a clinical study will produce results with greater statistical significance, it makes for speculation that differences between treated and untreated groups are not yet significant. The current melanoma study is not blinded (meaning administrators know which patients receive drug plus chemotherapy or simply chemotherapy) and this is the second time that patient numbers are increased in this study. However, the companies maintain that the larger study size is simply a conservative approach to increase the drug's chances of being approved.
Genasense is designed to inhibit expression of the Bcl-2 protein, which is overexpressed in many cancer cell types and functions to prolong cell survival. Aventis recently formulated an agreement with Genta to co-develop and co-market Genasense. For the rights to this drug, Aventis may pay up to $480 million as developmental milestones are met. With $165 million cash, or approximately $2.50 per share, Genta will be able to fund its Phase III studies, but the current investing environment is simply punishing companies with any disappointing drug development problems -- especially studies on a firm's leading drug candidate.
from Bull Market Biotech.... |
