HSV-2 therapeutic vaccine reduces viral shedding, genital lesions

WASHINGTON — The therapeutic vaccine candidate GEN-003 significantly reduced genital lesions and viral shedding in patients with genital herpes simplex virus-2, according to phase 2 data presented at the American Academy of Dermatology annual meeting.

The efficacy of the vaccine was evaluated in 310 adults with symptomatic genital herpes simplex virus-2 (HSV-2), according to presenter Zeena Nawas, MD, from the Center for Clinical Studies in Houston. Participants were randomly assigned to a vaccine containing 30 µg or 60 µg each of gD and ICP4 protein antigens with 25 µg Matrix M-2 (MM), 50 µg MM, or 75 µg MM, or placebo.

At 6 months, the GEN-003 vaccine demonstrated reductions in HSV-2 viral shedding in all vaccine groups that received 60 µg HSV-2 antigens vs. baseline. The highest reduction was observed in the vaccine group also assigned 75 µg MM (58%; P < .0001).

The only reductions in viral shedding among patients who received 30 µg antigens were in those who also received 50 µg MM (50%; P < .0001). All groups had fewer genital lesions compared with baseline except for patients assigned 30 µg/25 µg MM. Reductions in lesions ranged from 43% to 69% (P <.0001).

Nawas and Stephen K. Tyring, MD, medical director from the Center for Clinical Studies, concluded that the vaccine had “significant antiviral activity persisting 6 months post dosing with an acceptable safety profile.”

Reference:

Nawas Z, et al. F053. Late-Breaking Research: Clinical Trials. Presented at: American Academy of Dermatology Annual Meeting; March 4-8, 2016; Washington, D.C.

Disclosure: Nawas reports no relevant financial disclosures. Tyring reports receiving institutional funding from Agenus Inc., AiCuris GmbH & Co., Genocea Biosciences, Merck & Co., Inc., Nycomed Amersham and Vical Incorporated.