Biotech Values

[rancherho]

Wall & Doc:
1. Dr. Petrylak used data from both 9901 and 9902a. In 9902a 56.1% of ITT patients received a subsequent taxane (38.6% docetaxel) vs. 40.5% subsequent taxane (34.4% docetaxel) of crossover patients. http://www.fda.gov/ohrms/dockets/ac/07/briefing/2007-4291B1_03a.htm
2. The GVAX Ph2 clinical trial in HRPC clearly demonstrated the importance of a higher cell dosing for improved efficacy. Table 7 Analysis and Cell Dose of the Provenge FDA Statistical Briefing Materials for the AC meeting shows that while the Total Nucleated Cell Count (TNC) of all the processed immune cells in Provenge was statistically significant for increased survival (p=0.018), it was not statistically significant for increased survival for either CD54 upregulation (post/preprocessing) (p=0.395) or CD54 cell count (p=0.098). CD54 was the chosen as the marker for the approximate 20% of a patient’s cells that are dendritic antigen presenting cells matured as a result of processing. The TNC data indicates both that other immune cells, including, for example, B cells related to antibodies,may play an important role in the efficacy of Provenge, and that the total number of all nucleated immune cells, are important for increased survival.
3. The control arms in both the 9901 and 9902a Provenge trials were given the opportunity to crossover to 8015F upon progression; approximately 70% did. One third of a control patient’s immune cells supplied as a leukapherisis product were returned for infusion without processing to maintain blinding. The other two thirds were frozen and then thawed for processing the three Provenge 8015F doses for control patients receiving crossover treatment. Thus, the crossover patients would have received one third fewer total nucleated cells even in the somewhat unlikely event that the processing of frozen and thawed immune cells was as effective as processing fresh cells.
4. Thus, the benefit of docetaxel after lower dose Provenge given to crossover patients as compared to the higher dosing of its ITT patients is strikingly similar to the comparative effects of docetaxel after low dose and high dose GVAX. Clinical data for both Provenge and GVAX strongly support the conclusion, however, that the synergistic efficacy of each immunotherapy and docetaxel is substantially better that that of docetaxel alone, and docetaxel is the present standard of care in both asymptomatic and asymptomatic AIPC/HRPC.