US regulators may allow the next generation of vaccines to pass their high bar for approval.
On Wednesday, an advisory committee to the US Food and Drug Administration recommended approval of the cervical cancer vaccine, Cervarix, which contains a new adjuvant-substances that give extra pep to vaccines.
If the agency follows through on the committee’s advice, Cervarix will be the first vaccine approved in the US with an adjuvant other than alum-an adjuvant based on aluminum salts used for more than 60 years. The agency is expected to issue a decision by the end of September.
But the big question is whether the US will consider using adjuvants in pandemic H1N1 flu vaccine, a decision that has serious potential to stretch a limited world-wide supply. A positive decision on Cervarix could change the way the agency perceives adjuvanted H1N1 pandemic flu vaccine, an option that does not seem to be its first-choice, as I report in a recent article on adjuvants in Nature Medicine.
Cervarix, made by Glaxo Smith Kline, has already been approved dozens of countries, as have other vaccines with next-generation adjuvants, including several vaccines for seasonal flu.
European regulators are poised to approve vaccines for pandemic H1N1 flu vaccine containing an oil-in-water adjuvant-the same adjuvant used in seasonal flu shots given safely to millions of people in Europe. But US regulators are widely perceived by public health researchers as much more cautious.
The agency, nonetheless, also gave the green light on Thursday to clinical trials of an adjuvanted hepatitis B vaccine, manufactured by the biotechnology company Dynavax. The FDA had put the trials on hold 18 months ago pending investigation into whether vaccination may have been linked to a rare autoimmune condition that had developed in a trial participant. Now the company can continue to test its vaccine in people with chronic kidney disease who do not respond well to the standard hepatitis B shot.
So, it’s been a good week for adjuvants at the US FDA. We will see what that means ultimately for pandemic flu shots.
Researchers at Novartis are still awaiting data on the degree to which adjuvants can cut down the dosage of pandemic H1N1 vaccine. Meanwhile, studies out Thursday in the New England Journal of Medicine suggest that one shot of vaccine may be sufficient. And this Friday the NIH will also discuss early results from its clinical trials. Stay tuned.