Imunon Phase IB Ovarian Cancer Study Shows Strong Progression-Free Survival Treatment Effect Using A Synthetic Control Arm

Imunon is a mid-sized biopharmaceutical company that develops next-generation chemotherapy and immunotherapy agents for liver and ovarian cancers. One of their most promising therapies is GEN-1 – a cell transfection agent entraining persistent, local secretion of the interleukin-12 protein to stimulate the body’s immune system to kill cancer cells.

Imunon needed to assess the efficacy of their new compound. Although GEN-1 showed impressive progression-free survival (PFS) among stage III/IV ovarian cancer patients treated neoadjuvantly in the Phase Ib dose-escalating OVATION I study, the study was single-arm. That is, it did not have a control arm to compare against the PFS estimate. Imunon could not estimate the comparative efficacy in GEN-1 with their trial data alone, leaving them unsure whether to continue drug development.

It is not uncommon for early phase trials to move forward without a control arm. In the traditional drug development paradigm, investigators often identify compelling agents through single-arm Phase II trials and study them against a standard of care control arm in larger subsequent Phase III trials.