Lorcaserin Carcinogenicity Data Issue
FDA release advisory panel briefing document on Lorcaserin. It raised question regarding carcinogenicity data:
"A number of malignant tumor types developed in rats treated with lorcaserin for up to two years. An excess number of malignant mammary tumors developed in female rats treated with lorcaserin at doses within 7-fold of the proposed clinical dose of 10 mg BID. Male rats developed malignant mammary tumors when treated with lorcaserin at doses 17-fold higher than the proposed clinical dose. "
This is not entirely surprising to me. I raised this potential pre-clinical data issue after reading an article titled "Arena Pharmaceuticals: Locraserin and the Fallen Competitors: Analysis Part III" (http://www.gekkowire.com/?p=4186 comment by JQ on July 21, 2010).
I found suspension of ATHX-105 development for obesity due to pre-clinical toxicology data interesting since it was supposed to be selective to 5HT2c similar to Lorcaserin. I found the following from ATHX website http://bit.ly/aakDH8):
“In September 2008, we were notified by the FDA that our proposed phase II clinical trial was being placed on clinical hold, pending discussion with the FDA and resolution of several issues, some of which related to proposed trial design, and one of which related to a preclinical toxicology finding in rodents. While we were able to resolve each of the other issues regarding the clinical hold, we believe we will be unable to practically resolve the issue related to the toxicology finding in rodents, and as a result we have suspended further development of ATHX-105. The potential significance of the toxicology issue to humans remains unclear, but it appears to be a compound-specific effect that is not representative of the class of compounds we are developing. However, given that we would have to complete long-term toxicology studies in rodents and potentially other species in order to resolve the issue, and these studies may not be conclusive, we decided that further development of ATHX-105 may be too risky, expensive and time consuming, and therefore may not serve the best interests of our stockholders. Accordingly, we have withdrawn our IND application for ATHX-105, and suspended further development of this compound. ”
Posted on Sept. 14, 2010