GlaxoSmithKline plc's Shingrix vaccine for the prevention of shingles in adults aged 50 and over received marketing approval from Health Canada.
Shingrix contains Agenus Inc.'s proprietary immune adjuvant QS-21 Stimulon, an immune-potent adjuvant designed to help the body generate antibodies and T cells, which guard against infection with viruses, parasites and bacteria.
Shingles or herpes zoster is caused by reactivation of the varicella-zoster virus, the same virus that causes chickenpox. The risk for shingles increases after 50 years of age.
The approval in Canada, the first received worldwide, was based on a phase 3 trial where the vaccine demonstrated efficacy against shingles greater than 90%, independent of age, as well as sustained efficacy over the entire follow-up period of four years.
GSK's Shingrix is the first shingles vaccine to combine a nonlive antigen, unlike Merck & Co. Inc.'s Zostavax, which uses live attenuated virus of chickenpox, to trigger a targeted immune response and to generate a strong and sustained immune response.
Regulatory reviews of the vaccine are underway in the U.S., EU, Australia and Japan.
Previously, a U.S. Food and Drug Administration advisory panel recommended the approval of Shingrix in adults aged 50 and older. The panel was "very impressed" by efficacy data from clinical trials and said the vaccine represents an improvement over Zostavax.