ImmunoCellular Therapeutics ($IMUC) put out the word Wednesday afternoon that its dendritic cell-based vaccine for brain cancer flunked the key overall survival test in Phase II, news that swiftly wiped out more than half of the small biotech's market cap as shares instantly cratered.
The LA-based company started out with the good news, noting that ICT-107--its lead drug which had produced positive results in a small Phase I--cleared the hurdle for progression-free survival among patients with glioblastoma. But an effort to keep the focus on PFS didn't stand a chance once the company's release acknowledged that the improvement in overall survival, still the gold standard in cancer and the primary endpoint of the study, didn't measure up to a significant response.
The news is likely to count against everyone working in dendritic cell-based vaccines, particularly when it comes to spurring an immunotherapeutic response against brain cancer, which has proven to be a hard target in R&D. Cancer vaccines--unlike the checkpoint programs in the clinic--in general have had a hard time in the clinic.
On the plus side, the biotech noted that they had gathered OS data on 67 patient deaths out of the 124 patients in the study, with 103 events available for the PFS results. "In the matured data from the open label, phase I trial, the company observed a consistent benefit in both PFS and OS compared with historical controls, and on this basis thinks that it is possible that the primary OS benefit could be clarified as the phase II data mature," the company said in a release.
"The progression-free survival data look promising in this study," offered Harvard Medical School's Patrick Wen. "To my knowledge, this is the first time a placebo-controlled immunotherapy trial in glioblastoma has demonstrated a statistically significant improvement in a clinically relevant measure, such as progression-free survival. We await additional data to evaluate the effect on overall survival."
ImmunoCellular's CSO, John Yu, meanwhile, said he was "pleased" by the results and the company would consider possible next steps, including a Phase III.
- here's the press release