Agenus Commences Phase 1 Trial with Neoantigen Cancer Vaccine AutoSynVax™

LEXINGTON, Mass., April 5, 2017

The open-label trial will test the ASV vaccine in combination with QS-21 Stimulon^® adjuvant in patients with advanced cancer. The trial is intended to pave the way for further evaluation of combinations of ASV with Agenus' checkpoint antibodies targeting CTLA-4 and PD-1.

"AutoSynVax is one of three vaccine platforms proprietary to Agenus that have the potential to expand cancer patient populations that benefit from immunotherapy," said Dr. John Castle, Ph.D., Senior Director Computational Biology and Genomics at Agenus. "Our innovative algorithms, clinically validated HSP-based antigenic peptide delivery system, QS-21 Stimulon, and a portfolio of checkpoint antibodies place us in a uniquely advantageous position to potentially treat patients with advanced malignancies." Dr. Castle is the lead author of pioneering research¹ that demonstrated feasibility of identifying neoantigen immunogens that evoke anti-tumor immunity.

This week at AACR Agenus scientists presented evidence that ASV mediates tumor control and lasting immune memory in murine models of cancer. Additional data indicated that ASV cooperates with a surrogate CTLA-4 targeted antibody to bolster anti-tumor immunity in a mouse model of melanoma.

ASV is a personalized cancer vaccine platform that involves identification of tumor neoantigens unique to each patient using genomic sequencing. Each tumor mutational signature is interrogated using advanced bioinformatics algorithms derived from mass spectrometry profiling and structural biology modeling to catalogue and rank the tumor antigens that arise from these mutations. Neoantigens computationally predicted to be most immunogenic are incorporated into the so-called vaccine 'blueprint', synthesized, complexed with heat shock proteins (HSPs) and administered in conjunction with QS-21 Stimulon, Agenus' proprietary adjuvant. The HSP-peptide complexes accompanied by QS-21 Stimulon are designed to be efficient activators of T cells specific to the tumor neoepitopes and can elicit tumor control. Their activity is expected to be further enhanced by combinations with checkpoint modulators, such as our clinical-stage CTLA-4 (AGEN1884) and PD-1 (AGEN2034) antagonists, as confirmed by the preclinical data presented at AACR. The ASV platform could be applicable to a broad range of tumors.

Additional information about the trial can be found here.