Universal Pneumococcus Vaccine Candidate, GEN-004, shows positive results in Phase 1 study

Genocea Biosciences, Inc., a clinical-stage biopharmaceutical company developing T cell-enabled vaccines and immunotherapies, announced yesterday positive top-line results from a Phase 1 study of GEN-004, an investigational vaccine candidate designed to prevent infections from all serotypes of pneumococcus (Streptococcus pneumoniae), a major cause of infectious disease-related death globally. The Phase 1 study met its safety, tolerability and immunogenicity goals, including measurable increases in the blood of T helper 17 (TH17) cells, a rare cell type that provides immunity at epithelial and mucosal surfaces. Based on these data, the Company plans to advance GEN-004 into a Phase 2a trial in the third quarter of 2014.

Scanning Electron Micrograph of Streptococcus pneumoniae/CDC

“GEN-004 represents a novel approach to prevent colonization by all serotypes of pneumococcus in the nasopharynx and thereby potentially preventing serious pneumococcal infections,” said Richard Malley, MD, Division of Infectious Diseases, Boston Children’s Hospital. “These findings represent the first step toward potentially demonstrating proof-of-concept which could be shown in the upcoming Phase 2a trial.”

GEN-004 is the Company’s second clinical-stage program to emerge from its ATLAS™ platform, and is a universal vaccine candidate designed to induce a TH17 T cell response to reduce the colonization of all pneumococcal serotypes in the nasopharynx. In published preclinical studies, performed in collaboration with Boston Children’s Hospital, GEN-004 conferred significant protection against pneumococcal colonization. Colonization of the nasopharynx by pneumococcus is the first and necessary step prior to the development of serious and even life-threatening infections. Available vaccines protect by inducing B cell, or antibody, immune responses directed towards a minority of the more than 90 known serotypes of pneumococcus. Serotypes not included in the available vaccines are increasingly responsible for causing pneumococcal disease.

The Phase 1 study was a randomized, double-blind, dose-escalation, placebo-controlled clinical trial that enrolled 90 healthy adult volunteers. Serum IgG titers increased in a dose-dependent manner to each of the antigens included in GEN-004 and measurable increases in peripheral T_H17 responses were seen among subjects receiving the highest dose (100µg) with adjuvant. There were no serious adverse events related to the vaccine. Genocea intends to present the complete results of this trial at a major medical conference in 2014.