The Combination of ISA101b and Libtayo® Shows Promising Results in Patients Whose Head and Neck Cancer Progressed on Anti-PD1 Therapy

ISA Pharmaceuticals B.V., a clinical-stage biotechnology company developing immunotherapies to treat cancers and serious infectious diseases, presented the first clinical data of the combination of ISA101b (peltopepimut-S) and Regeneron’s anti-PD-1 Libtayo® (cemiplimab) at the ASCO annual meeting in Chicago.

Early data were presented regarding 26 patients with recurrent and/or metastatic Human Papilloma Virus type 16 (HPV16) positive oropharyngeal cancer (OPC, a form of head and neck cancer) who progressed on pembrolizumab or nivolumab, and were followed for at least 6 months. This population included patients that have never responded to prior anti-PD1 therapy. Patients were treated until disease progression, toxicity, treatment withdrawal or up to 24 months. Recruitment in this study is ongoing. Further information can be found on clinicaltrials.gov (NCT04398524).

The combination of ISA101b and cemiplimab in these patients resulted in an overall response rate (ORR) of 15.4%, as per investigator assessment. Long-term (≥6 months) disease stabilization was achieved in 26.9% of all patients. The combination of cemiplimab and ISA101b was generally well tolerated with a safety profile resembling that of anti-PD-1 monotherapy. There were two grade 3 adverse events related to ISA101b. Grade 4-5 events related to study treatment did not occur. Re-ignition of an anti-tumor effect of anti-PD-1 therapy after failure of checkpoint inhibition by the addition of a therapeutic vaccine is a unique feature.

Dr. Anthony Kong, Principal Investigator and Medical Oncologist at King’s College in London, said: “The initial results of this study are promising, given the high unmet medical need in this difficult-to-treat patient population.”

Leon Hooftman, Chief Medical Officer of ISA Pharmaceuticals, said: “The most impressive element of this data-set of anti-PD1 therapy-resistant head and neck cancer patients is the 6 months’ Disease Control Rate’ (DCR): it appears that the targeted therapeutic cancer vaccine ISA101b together with an anti-PD1 antibody can have a real stabilizing effect in a fair proportion of these sick patients.”