Merck's Zostavax not cost-effective for those in their 50s: Study

The CDC doesn't currently recommend Merck's ($MRK) shingles vaccine, Zostavax, for those between the ages of 50 and 60. And a new analysis of the vaccine's cost-effectiveness in that population suggests it should stay that way.

According to a study in the Annals of Internal Medicine, for every 1,000 people receiving Zostavax at age 50, just 25 shingles cases--and one case of persistent pain related to the disease--would be prevented, Reuters reports. Put another way, the vaccine costs more than $300,000 per quality-adjusted life-year; preventative treatments are typically considered cost-effective when they hit below the $100,000-per-QALY mark.

"Even though the vaccine is effective, it may not be cost effective," lead author Phuc Le of the Cleveland Clinic told the news service.

Right now, the CDC's Advisory Committee on Immunization Practices (ACIP)--whose green light is needed to secure widespread use and, often, insurance coverage--doesn't recommend the vaccine before age 60, despite an FDA approval indicating the vaccine is safe and effective for those in their 50s. The vaccine has demonstrated a 70% efficacy rate for those between the ages of 50 and 59, Dr. Eddy Bresnitz, Merck's executive director of medical affairs for adult vaccines, told Reuters in a statement.

"This may help explain why many private insurance plans include the vaccine on formulary, in spite of the absence of an ACIP recommendation among the 50-59 age cohort," he said.

As the new study's senior author, Michael Rothberg, pointed out, though, Zostavax protection lasts longer for those who receive the vaccine at age 60 or 70.

"If you get vaccinated when you're 50, you're pretty much unprotected by 60," he told Reuters.

Meanwhile, Merck may soon have some new competition to worry about from GlaxoSmithKline ($GSK). Earlier this year, a candidate from the British pharma giant posted 97.2% efficacy compared with placebo in more than 16,000 adults age 50 and older.

After approval, the shot "should be well positioned to capture market share from Zostavax," Cowen & Co. analysts wrote in April.

- get more from Reuters
- read the study abstract

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