Long term study confirms efficacy of ISA Pharmaceuticals' T-cell activating immunotherapy in combination with checkpoint inhibitor

- Data published in the Journal of ImmunoTherapy of Cancer confirms efficacy of combination treatment (anti-PD1 + ISA101b)

- Deep and durable responses have a profound positive effect on patient prognosis with patients disease-free for more than 44 months

- Improved tumour infiltration by immune cells predicted response to therapy

OEGSTGEEST, Netherlands, March 1, 2022 /PRNewswire/ -- ISA Pharmaceuticals B.V., a clinical stage biotech company developing immunotherapies to treat cancers and infectious diseases, today announces the publication of extension data from a key study using lead product ISA101b in the Journal of ImmunoTherapy of Cancer, ISA101 and nivolumab for HPV-16+ cancer: updated clinical efficacy and immune correlates of response, Guimaraes Sousa, Michael Curran, Bonnie Glisson et al. in collaboration with the MD Anderson Cancer Center in Houston, Texas.

The initial study by Massarelli et al. was published in 2018*. It investigated ISA101b in combination with anti-PD1 checkpoint inhibitor nivolumab (OPDIVO®) in head-and-neck cancer. In this open-label study, 22 patients with recurrent/metastatic Human Papilloma Virus type 16-positive (HPV16+) OroPharyngeal Cancer (OPC) were treated. The Objective Response Rate (ORR) in this difficult to treat patient population was 36%, with a median Overall Survival (mOS) of 17.,5 months.

Two patients in the first study displayed a Complete Response to treatment. This follow-up study shows they survived disease-free for more than 44 months.

Prof. Dr. Cornelis Melief, Chief Scientific Officer of ISA Pharmaceuticals, said: "We are delighted to see the results of this key study published as we continue to develop an exciting pipeline of cancer vaccines. Our work shows that a combination of ISA101b and anti-PD-1 remains a promising treatment vastly improving patient prognosis and long-term responses."

ISA's product portfolio consists of multiple synthetic long peptide (SLP) therapeutics for cancer and infectious diseases. The SLP approach is designed to unleash a durable and broad T cell immune response to specific diseases. It enables a patient's own immune system to attack and destroy tumour cells or viruses for significant clinical benefit. 101b is based on this technology and is currently being studied in HPV16+ cancers in combination with Libtayo® (cemiplimab) in three phase 2 clinical trials under a strategic collaboration with Regeneron. Libtayo is an anti-PD-1 antibody that is being jointly developed by Regeneron and Sanofi.

*Massarelli et al, JAMA Oncology 2018

About ISA101b

ISA101b immunotherapy targets human papillomavirus type 16 (HPV16) positive cancers. It induces strong and specific immune responses to the HPV16 virus, and (re-)establishes a powerful and targeted T-cell immune response against infected and/or cancerous cells and tissues. ISA101b is using ISA's proprietary Synthetic Long Peptide (SLP®) technology. ISA101b is in late-stage clinical trials for HPV16-induced cancer in a collaboration with US pharmaceutical company Regeneron.

About ISA Pharmaceuticals

ISA Pharmaceuticals is an immunotherapy company developing treatments for various cancers and infectious diseases. ISA Pharma has best-in-class technology to stimulate and activate the human immune system, specifically T cells, to fight diseased or infected cells. Its lead asset ISA101b is a clinical-stage asset for human papillomavirus type 16 (HPV16)-induced cancer. Other assets are in preclinical stage development and include immunotherapies to treat patients that suffer from chronic hepatitis B infections, cancers that over-express PRAME, cancers caused by other HPV types than HPV16, or SARS-CoV2 infections. For more information, please visit www.isa-pharma.com.