pidilizumab (CT-011)

The unprecedented structural data on Pidilizumab's interactions provided novel evidence that its legitimate target is the DLL1 protein and offered structural insight on how these molecules interact, shedding light on the pathways that could be affected by the use of this essential immunobiological. Communicated by Ramaswamy H. Sarma.

In April 2016, my colleague Dr Zev Wainberg presented Phase I safety and efficacy data at AACR (abstract CT011) with PARP inhibitor talazoparib in combination with alkylating agent temozolomide in cancer patients without gBRCA1/2+, demonstrating this to be a promising combination. We evaluated the molecular mechanisms underlying cancer cell lethality with talazoparib plus temozolomide in melanoma, small cell lung, ovarian, and colorectal cancer cell lines and mouse xenografts. Taking into consideration both the molecular data demonstrating efficacy of talazoparib plus temozolomide therapy in BRCA1/2 wild-type cell lines and mouse xenografts and the Phase I trial data showing safety and efficacy with this combination, PARP inhibitors likely have utility beyond treatment of gBRCA1/2+ patients. Use of the alkylating agent might be particularly important, as it is recognized during S-phase and trapping of PARP on the DNA could result in collapse of a stalled replication fork into a DNA double-strand break.