• Study designed to investigate the efficacy and safety of ISA101b added to checkpoint inhibitor therapy in Human Papilloma Virus type 16 (HPV16) induced oropharyngeal cancer (OPC).
• Trial is part of an extensive clinical development program for ISA101b in a collaboration with Regeneron.
• Top line interim results anticipated in third quarter of 2023.

Oegstgeest, 30 November 2022 – ISA Pharmaceuticals B.V., a clinical stage biotech company developing immunotherapies to treat cancers and infectious diseases, is delighted to announce that it has completed enrolment in its Phase 2 clinical trial named OpcemISA.

The OpcemISA trial has enrolled 194 patients and is a large randomized, double blind, placebo-controlled Phase 2 clinical trial. The trial will evaluate the efficacy and safety of the addition of ISA101b to checkpoint inhibitor therapy in patients with metastatic/advanced 1^st and 2^nd line HPV16 positive OPC. Primary endpoints will demonstrate overall response rate (ORR) and safety. Secondary endpoints include duration of response (DOR) and overall survival (OS). This trial is part of an extensive clinical development program of ISA101b in collaboration with US biotechnology company Regeneron.

“This large proof of concept trial of ISA101b has the potential to demonstrate for the first time that the combination of an HPV16-directed therapeutic vaccine with checkpoint inhibitor immunotherapy improves the short-term outcome and longer-term survival of difficult to treat head and neck cancer patients. The completion of enrolment is a major milestone for ISA Pharmaceuticals as it continues development of its SLP technology platform. We look forward to presenting top line interim data from this trial in the third quarter of next year.” said Dr. Leon Hooftman, Chief Medical Officer of ISA Pharmaceuticals.

Head-and-neck cancer can be a severe and life-threatening disease. HPV16 is a major cause of head-and-neck cancer. Recurrent and metastatic HPV16 positive OPC is a form of head-and-neck cancer with a high unmet medical need. In September 2021 ISA101b was granted Fast Track designation by the U.S. Food and Drug Administration (FDA) for the treatment of recurrent and metastatic HPV16 positive oropharyngeal cancer (OPC).

Details of the OpcemISA trial can be found at clinicaltrials.gov, identifier NCT036698718.

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