Press Release

Neon Therapeutics and Apexigen Announce Immuno-Oncology Clinical Trial Collaboration  

  • Phase 1b Study of Neon Therapeutics’ Personalized Neoantigen Cancer Vaccine with Apexigen’s CD40 Agonist for Metastatic Melanoma 

Cambridge, Mass. and San Carlos, Calif. – July 25, 2017 – Neon Therapeutics, Inc. an immuno-oncology company developing neoantigen-based therapeutic vaccines and T cell therapies to treat cancer, and Apexigen, Inc., a clinical-stage biopharmaceutical company focused on discovering and developing antibody-based therapeutics for the treatment of cancer, today announced an immuno-oncology clinical trial collaboration. Under this agreement, the companies plan to evaluate Neon Therapeutics’ proprietary personalized neoantigen vaccine, NEO-PV-01, in combination with and Apexigen’s CD40 agonist antibody, APX005M, for the treatment of patients with metastatic melanoma.

Neon Therapeutics’ lead program, NEO-PV-01, is a fully personalized neoantigen vaccine based on DNA mutations from patients’ individual tumors. Apexigen’s APX005M is a novel, humanized monoclonal CD40 agonist antibody that stimulates the anti-tumor immune response in the tumor microenvironment through activation of antigen-presenting cells of the immune system.

The companies will collaborate initially in a Phase 1b clinical trial sponsored by Neon Therapeutics that will evaluate the safety, tolerability and preliminary efficacy of NEO-PV-01 in combination with APX005M, as well as other immuno-oncology agents, in patients with metastatic melanoma.  Additionally, the trial will assess neoantigen-specific immune responses in peripheral blood and tumor tissue, as well as other markers of immune response.

“This clinical combination builds upon robust preclinical evidence suggesting potential synergy between a CD40 agonist and a neoantigen-based cancer vaccine,” said Richard Gaynor, M.D., president of Research and Development of Neon Therapeutics.  “We are excited to be working with Apexigen to combine these novel technologies in a clinical study.”

“In a prior Phase 1 clinical trial, APX005M has demonstrated immune stimulation in patients with solid tumors,” said Ovid Trifan, M.D., Ph.D., chief medical officer of Apexigen.  “We are excited to explore the combination of NEO-PV-01 and APX005M, because the scientific rationale indicates promise for this new combination approach to generate anti-tumor efficacy for patients with solid tumors.” 

About Neon Therapeutics, Inc.

Neon Therapeutics is an immuno-oncology company focused on developing novel therapeutics leveraging neoantigen biology to treat cancer.  A neoantigen-based product engine allows Neon to develop multiple treatment modalities, including next-generation vaccines and T cell therapies targeting both personalized and shared neoantigens.  Neon’s lead program is a personalized neoantigen vaccine that builds upon years of research and development at the Broad Institute of MIT and Harvard and Dana-Farber Cancer Institute, and is in multiple clinical trials.  For more information, please visit

About Apexigen, Inc.

Apexigen is a clinical-stage biopharmaceutical company discovering and developing a new generation of antibody therapeutics for oncology, with an emphasis on new immuno-oncology agents that could harness the patient’s immune system to combat and eradicate cancer. APX005M and the Company’s additional preclinical programs were discovered using APXiMAB™, Apexigen’s proprietary product discovery platform. This platform has enabled the Company and its collaboration partners to discover and develop high-quality therapeutic antibodies against a variety of molecular targets, including targets that are difficult to drug with conventional antibody technologies. Seven product candidates discovered using APXiMAB™ are currently in clinical development, either internally by Apexigen or by its partners. For more information, please visit


Neon Therapeutics, Inc.
Paul Goldsmith
Ten Bridge Communications, Inc.

Apexigen, Inc. 
Mark Nevins
Vice President, Business Development