The PR released by the company today, regarding tomorrow's poster presentation at SITC, deserves comment due to obvious deficiencies in the data of this marginal preclinical study. It is assumed that these experiments have been repeated and the scientists are presenting their "best results".
1. The K1735-C3H syngeneic mouse model has been studied extensively for possible immune intervention as therapy. Melanoma is a somewhat promising malignancy for immunotherapy and both preclinical and clinical trials have taken place in this model for a couple of decades.
2. The preclinical model as presented in this poster is flawed, as quickly observed for the data of the control group (receiving the C44 control antibody). Injection of the indicated dose of tumor cells subcutaneously resulted in such heterogeneous growth in the group of mice, it was impossible to determine effects of any agent. 2 mice had (desired) logarithmic, rapid growth of tumor; 3 mice had slow growth of tumor, so it must be surmised that the remaining mice (bottom of graph with measurable "bumps") had virtually no progressive tumor growth. Hence, the model, as used in this experiment does not work.
3. Treatment of mice with the anti-PS antibody, Ch1N11, resulted in no effect whatsoever in tumor growth (so much for that fantasy of anti-PS), and actually resulted in somewhat more favorable tumor growth (at least 9 mice has discernible progressive growth of tumor).
4. Treatment of mice with the much-studied CTLA-4 antibody resulted in little tumor growth in 10 mice, whereas 2 mice had progressive tumor growth. But, keep in mind, the model doesn't give uniform tumor growth to begin with...
5. The combination therapy showed no progressive tumor growth in all 12 mice (2 mice different than the use of CTL-4 alone).
6. In light of the absolute no effect of the anti-PS Ch1N11 upon tumor growth, it is difficult to believe that the combination therapy actually resulted in beneficial combination effects...which always brings up the fallacy of studies from PPHM, the lack of statistical verification of any result.
7. The histology studies lack any conviction due to complete lack of information regarding exactly what tumor did they dissect for examination; the progressive tumor, the tumor that grew poorly, or the tumor that showed necrotic features.
The statements regarding a favorable basis for clinical intervention are flawed. A poster session for one hour is 59 minutes too long. |
