An ongoing dialogue on HIV/AIDS, infectious diseases,
September 17th, 2017
Subunit Zoster Vaccine Soon to Be Approved — Should Patients Wait for It?
For the last year or so, conversations with patients about getting the zoster vaccine have gone something like this:
Patient: So should I get the shingles vaccine? I saw an ad for it on TV.
Me: Well, yes … and no.
Patient (confused — he/she has never heard me say anything but an enthusiastic “Yes!” to vaccines): What does that mean?
Me: There’s a better shingles vaccine coming soon, likely within a year. So I’d wait.
Now it looks like that wait is almost over.
This past week, an FDA advisory panel voted unanimously that the investigational subunit zoster vaccine is safe and effective for adults older than 50. The materials the panel reviewed are here.
FDA approval should follow soon — potentially next month — along with the critical review and recommendations from the Advisory Committee on Immunization Practices (ACIP).
The expert advisory panel based their decision on two pivotal randomized trials, ZOE-50 and ZOE-70, which compared the vaccine (administered as two doses) to placebo in people aged 50 and older or 70 and older, respectively. The studies enrolled nearly 30,000 subjects.
Vaccine efficacy was 97% in the first study, 89% in the second. The incidence of post-herpetic neuralgia was also reduced.
Importantly, adverse events were more common in vaccine recipients, but most were of mild severity. There was no significant difference in the incidence of severe side effects, deaths, or autoimmune processes.
Though these studies were not a direct comparison with the currently available live-attenuated zoster vaccine (Zostavax), remember that the efficacy of that vaccine is only around 50%.
Plus, it has been around long enough that we now know its efficacy wanes substantially over time.
That Zostavax is a live-virus vaccine creates additional difficulties. There is understandable concern — and confusion — about giving it to people with defects in cell-mediated immunity, for whom it’s contraindicated, and their household contacts, for whom it isn’t.
Finally, there are the practical difficulties of storing it before administration. Even clinics that do lots of immunizations — ours, for example — don’t have the required stand-alone freezer for storage of this vaccine. Many patients currently need to go to a pharmacy to get it, which adds an additional required step.
So this inactivated zoster vaccine won’t be just a “me-too” approval, but a real advance in prevention of what can be a truly debilitating condition. With the caveat that we lack safety data in very large patient populations — that should come after licensing — I’m not surprised the advisory panel voted the way they did.
It was exciting enough that I felt inspired to relay the following:
Big news because
1) Highly effective
3) Not live attenuated
5) Shingles can be BAD
5) Have been telling my pts about it for months! https://t.co/4HJrK0wNAo
— Paul Sax (@PaulSaxMD) September 13, 2017
Which just goes to show that I can’t count.