WASHINGTON — U.S. health officials on Tuesday authorized a plan to stretch the nation’s limited supply of monkeypox vaccine by giving people just one-fifth the usual dose, citing research suggesting that the reduced amount is about as effective. The so-called dose-sparing method calls for injecting Jynneos vaccine under the skin, rather than deeper tissues. This may help boost the immune system’s effectiveness. Recipients would still get two shots spaced four weeks apart. This unusual move is an admission that the U.S. lacks sufficient supplies to protect everyone from this rapidly-emerging virus.
That includes 1. 6 million to 1. 7 million Americans considered by federal officials to be at highest risk from the disease, primarily men with HIV or men who have a higher risk of contracting it. Vaccinating that group would require about three times more full doses than the roughly 1. 1 million that officials have made available.
The White House’s monkeypox response coordinator, Robert Fenton, said the plan would help the U.S. “stay ahead of the virus.”
“It’s safe, it’s effective, and it will significantly scale the volume of vaccine doses available for communities across the country,” Fenton told reporters.
The Biden administration declared monkeypox a public health emergency last week in an effort to slow the growing outbreak that has infected more than 8,900 Americans. Officials announced a separate determination Tuesday that allows the Food and Drug Administration to expedite its review of medical products or new uses for them, such as the dose-sparing technique for Jynneos.
The FDA authorized the new approach for adults 18 and older who are at high risk of monkeypox infection. The agency stated that younger people may also be vaccinated if they have been deemed to be at high risk. However, they must still receive the standard injection.
The announcement represents an about-face from last month, when the FDA and other agencies repeatedly stressed that two full vaccine doses were necessary for adequate protection.
But regulators now point to a 2015 study showing that vaccination with one fifth of the traditional dose generated a robust immune-system response comparable to that of the full dose. About 94% of people receiving the smaller dose had adequate levels of virus-fighting antibodies, compared with 98% of those receiving the full dose, according to the study funded by the National Institutes of Health. According to the agency, the NIH plans an additional test of this technique over the next few months.
Vaccine manufacturers often make their shots in order to offer more protection. It’s possible that even a lower dose of vaccine could prove as effective.
But some experts and advocates warned there is little data to support the policy and worried it could backfire if it reduces the vaccine’s effectiveness.
” We are concerned about the lack of data on the dose and the administration methods. It could give people false confidence in their protection,” David Harvey, National Coalition of STD Directors stated.
Smaller doses require an injection that only penetrates the top of the skin. This is in contrast to the deeper layers between skin and muscles. This is a more rare technique and may be difficult to master for health professionals. It’s also associated with more side effects such as redness, itchiness and swelling.
The shallower injection is thought to help stimulate the immune system because the skin contains numerous immunity cells that target outside invaders.
The Centers for Disease Control and Prevention stated that it would provide education materials and a wider awareness campaign for U.S. healthcare departments on this technique.
Rationing vaccine doses is common in Africa and other parts of the world with limited health resources. In recent years the World Health Organization has endorsed the approach to address outbreaks of yellow fever, polio and other diseases. This isn’t an unusual situation,” said Dr. William Moss, Johns Hopkins’ Vaccine Access Center. “It comes down to the public health decision-making: In the midst of an outbreak where you have insufficient supply, do you make this tradeoff?”
When the first COVID-19 vaccines became available in late 2020, the U.K. government prioritized giving a first dose to as many people as possible before providing second vaccinations. Both Canada and the United Kingdom have adopted single-dose vaccination strategies. This prioritizes people at highest risk of monkeypox. And health departments in several large U.S. cities adopted a similar strategy amid limited supplies, including New York, San Francisco and Washington.
U.S. officials have shipped more than 617,000 full vaccine doses to state and local health departments and plan to distribute another 380,000 in coming weeks. It’s recommended that this vaccine be given to people who are at risk of getting the disease. The Biden administration was criticised for failing to quickly mobilize millions of doses from its strategic national stockpile. Officials have ordered 5 million shots since July, but most aren’t expected to be delivered until 2023.
The U.S. government owns bulk vaccine ingredients equivalent to 16. 1 million doses under contracts with Danish manufacturer Bavarian Nordic. But the material needs to be sealed in vials, a process that’s expected to take months as the small company fields orders from other nations.
HHS responded to criticism last week about the pace and timing of the government’s vaccine decisions.
“We were thoughtful about how and when to use bulk vaccine because once you remove it from bulk, you lose years of shelf life,” a spokesperson said in an emailed statement.
The FDA approved Jynneos in 2019 as a vaccine to protect against smallpox/monkeypox. This was partly based on monkey studies. According to FDA labeling, animals who received two doses of vaccination had twice the chance to live than monkeypox-infected ones.
Additional human studies showed people who received Jynneos had an immune response similar to those who received an older smallpox vaccine. Jynneos was not tested on humans infected with monkeypox (or its related smallpox) which were eradicated many decades ago.
That’s typical of many of the vaccines and drugs in the national stockpile that treat rare or deadly pathogens like anthrax or the plague.
The U.S. government has spent more than $1 billion developing and stockpiling the freeze-dried vaccine, which replaced an earlier liquid version that had a shorter shelf life. Bavarian Nordic has a 10-year contract with the U.S. to supply the new vaccine.
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The US will increase monkeypox vaccine supplies with lower doses was first published on Associated Press .
