– Top-line viral shedding data expected in mid-2016 –
– Six month clinical efficacy data against potential Phase 3 endpoints expected in 2H 2016 –

CAMBRIDGE, MA, USA I January 29, 2016 I Genocea Biosciences, Inc. (GNCA), a biopharmaceutical company developing T cell-directed vaccines and immunotherapies, today announced the commencement of the dosing phase in a Phase 2b clinical trial for GEN-003 for the treatment of genital herpes. Patient screening for the trial, which was initiated in December 2015, is complete. The Company expects to report top-line viral shedding data from the immediate post-dosing observation period in mid-2016 and clinical efficacy data against potential Phase 3 study endpoints at six months after dosing in the second half of 2016.

“This is the first study testing potential Phase 3 endpoints with an improved formulation of GEN-003 manufactured with commercially-scalable processes,” said Seth Hetherington MD, chief medical officer of Genocea. “This placebo-controlled data, combined with the positive clinical and virologic efficacy and safety data from our first two clinical trials, will be the foundation for our end of Phase 2 meeting with the FDA, planned for the fourth quarter of 2016.”

The Phase 2b study will enroll approximately 135 subjects from nine institutions in the United States. Subjects will be randomized to one of two dose levels of GEN-003 or placebo, and receive three injections at 21-day intervals. Viral shedding rate reductions will be measured to demonstrate the activity of the new formulation. The study will also compare GEN-003 efficacy to placebo for the clinical endpoints of: the proportion of patients who are lesion free at six and 12 months after dosing; the time to first lesion recurrence after dosing; and, the impact on percentage of days with genital herpes lesions at six and 12 months after dosing. All subjects will be followed for 12 months after the last dose.

Genocea is currently conducting a Phase 2 dose optimization study with an anticipated 12-month data read out later in the first quarter of 2016. In October, the Company announced positive results from a planned interim analysis of data collected six months after dosing. At its best performing dose of 60 µg per protein / 75 µg of Matrix-M2TM adjuvant, GEN-003 demonstrated a statistically significant 58 percent reduction from baseline in the viral shedding rate (p<0.0001), the primary endpoint of the study. In a planned secondary analysis, the proportion of patients receiving GEN-003 who were lesion-free at six months after dosing ranged from approximately 30 to 50 percent, similar to results reported in clinical trials with oral antiviral therapies. In addition, the time to first recurrence after completion of dosing showed a range of 152 days to greater than 180 days among dose groups.  In a further secondary analysis measuring the impact on genital lesion rates, GEN-003 demonstrated sustained and statistically significant reductions from baseline in five of six dose groups ranging from 43 to 69 percent. The Phase 2 study continued to show that GEN-003 is safe and well tolerated by patients, with no serious adverse events related to the vaccine.

About GEN-003
Inducing a T cell response against genital herpes is critical to treating the clinical symptoms of disease and controlling transmission of the infection. GEN-003 is a first-in-class T-cell directed immunotherapy designed to elicit both a T cell and B cell (antibody) immune response. The immunotherapy was designed using Genocea’s ATLAS™ platform, which profiles the comprehensive spectrum of actual T cell responses mounted by humans in response to disease, to identify antigen targets that drive T cell response. GEN-003 includes the antigens ICP4 and gD2 along with Matrix-M2TM adjuvant, which Genocea licensed from Novavax, Inc. For more information about GEN-003, please visit http://www.genocea.com/platform-pipeline/pipeline/gen003-for-genital-herpes/.

About Genital Herpes
Genital herpes affects more than 400 million people worldwide and causes recurrent, painful genital lesions. It can be transmitted to sexual partners, even when the disease is asymptomatic. Current genital herpes therapies only partially control clinical symptoms and viral shedding, a process which drives disease transmission. Incomplete control of genital lesions and transmission risk, expense and the perceived inconvenience of taking a daily medication are hurdles for long-term disease management. Immunity through T cells is believed to be particularly critical to the control and possible prevention of genital herpes infections.

About Genocea Biosciences, Inc.
Genocea is harnessing the power of T cell immunity to develop life-changing vaccines and immunotherapies. T cells are increasingly recognized as a critical element of protective immune responses to a wide range of diseases, but traditional discovery methods have proven unable to identify the targets of such protective immunity. Using ATLAS, its proprietary technology platform, Genocea identifies these targets to potentially enable the rapid development of medicines to address critical patient needs. Genocea’s pipeline of novel clinical stage T cell-enabled product candidates includes GEN-003 for genital herpes, GEN-004 for the prevention of infection by all serotypes of pneumococcus (development suspended), and earlier-stage programs in chlamydia, genital herpes prophylaxis, malaria and cancer immunotherapy. For more information, please visit the company’s website at www.genocea.com.

SOURCE: Genocea