Amid Zostavax Concerns, Demand for Newer Shingles Vaccine Shingrix Soars

As a growing number of doctors move away from Zostavax, due to concerns about side effects of the shingles vaccine, GlaxoSmithKline indicates that it plans to spend $100 million to boost the production of Shingrix, as demand for the newer shingles vaccine skyrockets.

The drug manufacturer issued a press release last week, announcing it is making a massive investment into a Hamilton, Montana facility to increase production of Shingrix. The decision comes after company officials announced in December that Shingrix vaccine shortages may occur throughout 2019.

Shingrix (recombinant zoster vaccine; RZV) was the second vaccine approved for prevention of shingles among adults, which involves two doses for inoculation. When it was introduced, Zostavax (varicella zoster vaccine; VZV) was the only shingles vaccine on the market, which is manufactured by Merck and involvces a single dose. However, unlike Zostavax, Shingrix does not involve the use of a live virus, which has been linked to reports of problems among patients who received Zostavax.

Merck now faces hundreds of Zostavax lawsuits brought by individuals nationwide who experienced severe shingles outbreaks or auto-immune disorders after receiving their version of the shingles vaccine, involving allegations that the live virus was “under-attenuated” and not sufficiently weakened to avoid the risk of reactivating the dormant virus in many individuals.

Amid rising Zostavax concerns, CDC researchers have indicated that the Shingrix success rate is above 90%, which is in line with most vaccines, leading doctors to conclude Shingrix is safer.

In November 2018, a study published in The BMJ, which found that Shingrix is 85% more effective at preventing shingles than Zostavax, further accelerating the move away from Zostavax by many doctors.

“For more than a decade, our Hamilton facility has supported GSK’s adjuvant system development program,” Jack Bailey, President, US Pharmaceuticals, GSK, said in the press release. “By expanding the adjuvant system production capabilities in Hamilton, we will continue to deliver long-term and sustainable supply for key vaccines, including SHINGRIX.”

The relative safety of Shingrix compared to Zostavax is likely to be a main focus of the litigation filed against Merck, which also includes allegations that the drug maker knew about the safer alternative design, but placed desire for profits before consumer safety.