“It’s a completely different approach,” said Thomas Heineman, head of Glaxo’s global vaccine development division. “The new adjuvant was developed by (Glaxo) and has been used in trials of vaccines for malaria, hepatitis B, and tuberculosis.”
The international study of the shingles immunization, published last month in the New England Journal of Medicine, gave two doses of either the Glaxo vaccine or a placebo to 15,400 people age 50 and over. Only six vaccine recipients in the entire group developed shingles over the three-year follow-up, compared to 210 in the placebo group, making the vaccine about 97 percent effective. Moreover, age did not diminish the potency; among people 70 and older, the vaccine was 98 percent effective.
With any adjuvant, there is a hypothetical risk of overstimulating the immune system, but Heineman said “that is not something we’ve seen.” Though the vaccine group reported more temporary injection-site reactions and body-wide complaints than those who got the placebo, the numbers of serious side effects, autoimmune disease, and deaths were similar in both groups.
Glaxo has not said when it hopes to file government approval of the vaccine. The company is completing studies of the vaccine in people age 70 and older and in immune-compromised patients, for whom the current vaccine is not safe. A U.S. Food and Drug Administration review can take six months or more.
One question Glaxo “has no formal plans at this point” to explore, Heineman said, is whether people who have had Zostavax could also get the Glaxo vaccine.