The FDA approved GlaxoSmithKline’s new shingles vaccine on Friday. The vaccine, Shingrix, is said to be more effective than the only other shingles vaccine on the market, Merck’s Zostavax.
Shingrix is the second shingles vaccine to come to market, but it is poised to dominate the space. In Phase 3 trials of 38,000 patients, Shingrix demonstrated 90% efficacy in preventing shingles across all age groups—compared with Zostavax’s 50%. Shingrix will cost $280 for the required two shots, while Merck’s one shot costs $223. Most insurance plans will cover shingles vaccination.
Shingrix is a non-live recombinant subunit vaccine. It has been genetically engineered and contains an effectiveness-boosting ingredient. GSK studies showed that, once administered, it retained 90% of its effectiveness for four years, and follow-up studies indicated that effectiveness could last years beyond that.
Zostavax is made with a live weakened virus, meaning that it cannot be used in immune-compromised patients. One study found that it is no longer effective after eight years.
In addition to preventing shingles, both drugs reduce the risk of postherpetic neuralgia, a form of chronic nerve pain and the most common complication related to shingles. However, Shingrix reduces the risk of nerve pain by nearly 90%, while Zostavax only reduces it by 67%.
According to Thomson Reuters data, annual sales for Shingrix are expected to reach $1.36 billion by 2023. In 2016, Zostavax sales were $685 million.
Shingrix, like Zostavax, is approved in adults age 50 and over. More than 99% of Americans over 50 are infected with the varicella zoster virus, which causes shingles and chicken pox, and one in three will develop shingles in their lifetime. In adults 85 and older, the risk increases to one in two.