Genocea Biosciences closed a $35 million Series B round of venture financing. Proceeds will help move its lead program, a therapeutic vaccine for herpes simplex virus type 2 (HSV-2) infections, into clinical development. The funds will also advance the company’s research pipeline, which includes prophylactic vaccine programs addressing Chlamydia trachomatis, Streptococcus pneumoniae, HSV-2, and Plasmodium falciparum.
These programs were developed on Genocea’s platform for the discovery of T-cell antigens. The firm believes that its approach addresses several key challenges to antigen discovery, including: identification of promising antigens from the thousands of possible candidates for each pathogen and selection of antigens with potential to provide protection across diverse populations.
At the core of Genocea’s antigen-discovery technology is a high-throughput screening process that mimics the natural mammalian immune response to protein antigens, including antigen processing and presentation by antigen-presenting cells (APCs); CD4+ and CD8+ T-cell recognition of APC-displayed peptides; and immune activation.
The company says that it screens all of a pathogen’s proteins against T cells obtained from human donors with diverse HLA types who have either generated a potentially protective or ineffective immune response after exposure to a target pathogen. As part of its discovery approach the company creates a library of each pathogen’s complete proteome.
Genocea reports that its discovery process allows the 2,000–3,000 proteins produced by a pathogen to be winnowed down to a set of 100–200 protein antigens that correlate with natural immunity. A subset of proteins from that group is selected for in vivo testing based on recognition across multiple HLA supertypes and other criteria. The goal is to identify two to five antigens for formulation and development into a vaccine candidate that will be protective across diverse ethnic populations.
Commenting on the closure of the company’s Series B financing, CBO of Genocea Chip Clark says, “We believe this substantial funding round validates the promise of our proprietary discovery platform and underscores the significant unmet medical need for new vaccines in our target diseases.”
New investors Johnson & Johnson (J&J), MP Healthcare Venture Management, and Skyline Ventures joined existing investors Auriga Partners, Cycad Group, Lux Capital Management, Morningside Ventures, Polaris Venture Partners, and SR One.