Herpes Vaccines in Clinical Trials

For the first time, there is a promising vaccine to treat Herpes Simplex Virus type 2 (HSV-2), commonly known as genital herpes.

HSV-2 is an infection that infects 24 million in the United States, second in prevalence only to HPV among sexually transmitted viruses in the U.S.

The far more common type of herpes, which causes cold sores, is HSV-1.

Many people are infected with HSV-1 or HSV-2 without even knowing it, until they take a blood test.

A recent paper in the Journal of Infectious Disease provides insights for the clinical trial of Genocea's genital herpes vaccine candidate GEN-003.

The good news is that infected patients did respond to the herpes vaccine. The bad news is that the response was not impressive.

This Phase Ia/II trial summary results were:

• The vaccine was found to be safe
• The rate of viral shedding was reduced from 13.4% to 6.4%
• The rate of lesions in participants who got either the 30 µg or 100 µg dose was cut in half.

“These long-term durability data reinforce our conviction that GEN-003 could become the cornerstone treatment for patients with genital herpes,” Chip Clark, president and CEO of Genocea, said in the press release.

Genocea has completed its End of Phase 2 meeting with the FDA, and expects GEN-003 will be ready for phase 3 development by the end of 2017.

“From these data, GEN-003 would seem to have an uphill battle. Based on my experience, It is unlikely that the company (and future investors) will be satisfied with a vaccine that works about as well as Valtrex. Given the moderate degree of efficacy seen in infected patients, 003 seems unlikely to work well prophylactically,’ said the American Council on Science and Health.

There are other herpes vaccines in development. Infection with varicella zoster virus (VZV) causes two distinct clinical conditions.

Primary VZV infection causes varicella (chickenpox), a contagious rash illness that typically occurs among children. VZV can reactivate clinically decades after initial infection to cause herpes zoster (shingles), a painful cutaneous eruption that occurs most frequently among older adults.

GSK’s shingles vaccine candidate Shingrix (HZ/su) met its primary objective of inducing a strong immune response in older patients in a phase 3 revaccination trial.

Shingrix is being developed for the prevention of shingles, better known as herpes zoster, a painful, itchy rash condition caused by reactivation of latent chickenpox virus.

The vaccine candidate was shown to have yielded positive results in patients who were previously vaccinated with the currently available live-attenuated zoster vaccine (ZVL) for shingles prevention.

The Centers for Disease Control and Prevention (CDC) recommends a single dose of herpes zoster vaccine for people 60 years old or older, whether or not the person reported a prior episode of zoster. People with chronic medical conditions may be vaccinated unless a contraindication or precaution exists for their condition.

Zoster vaccine is a live virus vaccine. It can be administered concurrently with influenza and pneumococcal vaccines.

Vaccine discounts can be found here.