Hoping to expand monkeypox vaccine supply, US paves the way for new route of administration
After making it clear that the US’ current monkeypox vaccine supply is insufficient, the FDA on Tuesday authorized a new route of administration that should increase the number of available doses by five-fold.
Regulators cleared Bavarian Nordic’s Jynneos vaccine for intradermal injection in adults older than 18. Unlike subcutaneous injection — the current method by which vaccine is delivered under the skin — an intradermal jab goes directly into the skin. It’s believed that this method requires less vaccine, since the dermis is rich in dendritic cells which specialize in taking up foreign antigens and presenting them to the immune system, according to Daniel Kuritzkes, chief of infectious diseases at Brigham and Women’s Hospital in Boston.
“In recent weeks the monkeypox virus has continued to spread at a rate that has made it clear our current vaccine supply will not meet the current demand,” FDA commissioner Robert Califf said in a news release.
The news comes as the New York Times reports that about 20 million doses of the vaccine have expired in the US national stockpile.
The downside to intradermal injection? It’s more difficult to perform correctly, William Schaffner, a professor in Vanderbilt University’s infectious diseases division, told Endpoints News on Tuesday.
As Schaffner put it, intradermal injection is “a bit of an art form.” It was most commonly used for tuberculosis skin tests; however, he noted that it’s likely the average nurse now may have never given an intradermal inoculation, or only had brief exposure. It’s much easier to stick a needle through the skin for a subcutaneous injection.
“That’s easy. I can show you how to do that in five minutes,” Schaffner said.
But getting it into the skin correctly takes technique. If it isn’t done properly, vaccine can either leak out or make its way through the skin, where it may be less effective given the lower dose, he said.
“The reason this isn’t employed more is that it’s not easy,” he added.
The White House National Monkeypox Outbreak Response team will oversee the rollout of this new strategy and coordinate with the CDC, FDA, HHS and local officials, according to a fact sheet put out on Tuesday. Providers currently have all the supplies they need, according to the White House, and the Biden administration added that it’s launching a “robust effort to train health care workers and providers.”
The 400,000 vials of Jynneos vaccine in the national stockpile should expand to 2 million doses using intradermal injection.
In addition, the FDA authorized the Jynneos vaccine for individuals under 18 years old who are at high-risk for monkeypox infection, though adolescents must receive subcutaneous injection.
To date, HHS has made 1.1 million doses of the Jynneos vaccine available for order and has shipped more than 620,000 doses. Plus, the Administration for Strategic Preparedness and Response announced that it will procure an additional 5.5 million vials, which translates to more than 25 million doses via intradermal injection.
Last week, officials said an additional 150,000 vials will arrive two months ahead of schedule in September.
While Jynneos remains the only vaccine in the US specifically approved for monkeypox, HHS has also cleared states and jurisdictions to order the smallpox vaccine ACAM2000. However, the agency previously noted that ACAM2000 isn’t recommended for everyone “due to significant side effects.”