Demand for monkeypox vaccine drives NIH to test ways to expand supply

aAs the monkeypox outbreak continues to grow, one thing seems very clear. Global demand for monkeypox vaccine is outstripping supply, and this trend is likely to continue for some time.

Scientists at the National Institutes of Health are preparing to explore possible workarounds. We are putting the finishing touches on the design of a clinical trial to evaluate the two methods.

They found that split doses, which use one-fifth the normal dose of vaccine per person, offer as much protection as the current regimen of two full vaccinations, 28 days apart. I am planning to test if It also tests whether a single dose is enough to prevent infection.

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The former approach would allow approximately five times more people to be vaccinated than the current licensed approach, and the latter would allow twice as many people to be vaccinated with the existing vaccine supply.

Answers from this study by late November or early December could greatly aid efforts to control this unprecedented monkeypox outbreak. So far this year, he has reported more than 25,000 confirmed cases in more than 80 countries, of which more than 6,600 cases have been detected in the United States.

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“The question people at NIH are asking is a very important question,” Myron “Mike” Levine, a vaccine expert who wasn’t involved in organizing the trial, told STAT. do you want? [Jynneos] Will we be able to vaccinate more people than we could with the currently permitted doses?

The current outbreak is the first outside of a country where the monkeypox virus is endemic to small forest animals, and was first detected in the UK in mid-May. We found four cases in other men who had sex with men who had never traveled to a country where the disease was endemic. It spreads to

Demand for the monkeypox vaccine has surged because the federal government has reported cases of monkeypox in states and territories where Gynneos, originally developed by Danish vaccine maker Bayern Nordic, was developed to combat smallpox. That’s when I started dosing. Vaccines are now available in the country to people who are contacts of known cases and to men who are at high risk due to presumed exposure.

The Food and Drug Administration and the Centers for Disease Control and Prevention have stressed that vaccines must be used as licensed, but have announced that the two-dose regimen will only be given in a few locations. First dose For now, we’re trying to offer some protection to more at-risk people. Others have said that some people who have come forward to be vaccinated will be given one dose, but only men who are considered at high risk will be given a second dose.

“There is no consistent message here.

Beigel, who described the study at a meeting hosted by the World Health Organization earlier this week to shape the research needed for a monkeypox vaccine, said in an interview that the three-arm trial plans to enroll 210 people. The study, which will be conducted at six to eight trial sites in the United States, is expected to begin later this month or early September, he said.

One-third of control subjects will receive two full doses of Jynneos separated by 28 days. The second group receives a full dose of vaccine. In the third group she also gets two doses 28 days apart. However, each of these doses is one-fifth of the full dose and the vaccine is administered intradermally instead of intramuscularly.

This study does not assess how protective different regimens are. Much larger clinical trials involving thousands of participants are needed to estimate vaccine efficacy. Instead, the goal is to study whether two dose-sparing approaches produced antibody levels equivalent to at least two dose regimens. Tolerance and reactogenicity are also compared.

It has long been known that intradermal vaccination, in which a small needle is inserted just below the top layer of skin, can activate a strong immune response even with low doses of vaccine. It’s a technology that’s not commonly used, so vaccinated people will need to be trained. And this approach could cause short-term discomfort for vaccinated people, Beigel said.

“subcutaneous [administration] It was actually more painful than intradermally, but it was more itchy and reddish intradermally,” he said. The vaccine supply could be expanded fivefold, but people would have to put up with more redness and itching. And is that a trade-off that people are willing to make?”

There are good reasons to believe that divided doses are effective. Vaccine manufacturers often make the mistake of going big instead of going small when conducting initial dose trials of new vaccines. Using a dose large enough to prove protection in the first round is more important than trying to figure out what the minimum effective dose is.

Consider the HPV vaccine. Initially he was licensed as a three-dose product, but now in some cases he is being dosed twice and earlier this year an expert panel advising him on vaccine policy to the WHO said: concluded to One dose was enough For girls and women under the age of 20.

said Levine, associate dean for global health, vaccinology and infectious diseases at the University of Maryland School of Medicine. .

Split dosing in outbreak settings has been used effectively in the past.a few years ago, a big yellow fever epidemic In Angola and the Democratic Republic of the Congo, where the global supply of yellow fever vaccine has been nearly exhausted, WHO has recommended a one-fifth dose.

Still, just because an approach has worked in some situations doesn’t mean it’s guaranteed to work in this one, warns Levine. It is one of the important aspects of pharmaceutical formulations.

Beigel is a little skeptical that a single dose approach will prove effective. Primate research A single dose of vaccine was shown to protect against a lethal dose of monkeypox virus.

The animals were completely unprotected, he said, noting that they developed several pox lesions.

“It seemed to keep the monkeys alive, but it didn’t prevent the disease — or at least it didn’t prevent the disease outright. [this is] I was completely reassured that one dose was enough,” said Beigel.