Immunization Strategy With Intra-tumoral Injections of Pexa-Vec With Ipilimumab in Metastatic / Advanced Solid Tumors.

Summary

The success of anti-CTLA4 therapy has inaugurated a paradigm shift in oncology where drugs target the immune system rather than cancer cells in order to stimulate the anti-tumor immune response. In situ immunization is a strategy where immunomodulatory products such as pathogens are injected into one tumor site in order to trigger a systemic anti-tumor immune response. Of importance, pre-clinical rationale has demonstrated that combination of anti-CTLA4 therapy together with intra-tumoral (IT) oncolytic virus can overcome primary resistance to systemic anti-CTLA4 therapy. Pexastimogene Devacirepvec (Pexa-Vec) is one of the new vaccinia oncolytic viruses genetically modified to express GM-CSF. This new and innovative oncolytic virotherapy should therefore synergize with anti-CTLA4 therapy via virus-induced tumor cell death \& tumor-antigen release, GM-CSF-induced recruitment/maturation/activation of antigen presenting cells, and anti-CTLA4-induced Treg blockade/depletion. Intra-tumoral delivery of immunostimulating agents should, therefore, provide lower toxicity of mAb targeting immune checkpoints. Of note, IT injections of GM-CSF-encoding oncolytic viruses have already been shown to induce immune-mediated tumor responses on local (injected) and distant (not injected) tumor sites. In solid injectable refractory/relapsing metastatic tumors, we make the hypothesis that the addition of Pexa-Vec to IT ipilimumab (anti-CTLA4 Ab) will overcome primary/secondary resistance to standard therapy and/or immunotherapy with a better in situ tumor antigen specific T-cell priming. Our proposal is to conduct a 2-part Phase I clinical trial in order to define the feasibility, the safety and the anti-tumor effects of intra-tumoral injections of ipilimumab in combination with the oncolytic virus Pexa-Vec. Dose escalation step will define the MTD and RP2D of that in situ immunization strategy. Expansion part will assess the anti-tumor effect of the combination.

Timeline

Start

2017-01-03

Primary completion

2022-04-13

Completion

2022-06-06

Drugs

Indications