How can we vaccinate people against monkeypox faster? dose-saving

Demand for Jynneos’ monkeypox vaccine far outstrips supply. The cases are increasing rapidly. Last week there were more than 25,000 cases worldwide, with the US accounting for 25% of all cases.

As I have already written Medicines for monkey pox, The Jynneos vaccine is manufactured by Bavarian Nordic and is FDA approved. They have a ten-year deal with BARDA worth $539 million to supply freeze-dried vaccines. Unfortunately, there were only enough cans for ~1100 people in the national supply. The 20 million doses we had at one time had expired and were not being replaced. There have been a number of delays in converting to a longer shelf life freeze dried product and the Danish facility has been awaiting update and FDA inspection. 1.4 million cans sat in Denmark. They are now scheduled for delivery.

In the meantime, patients are up the proverbial stream, and the FDA, WHO, and others are looking for alternatives.

The Jynneos vaccine is given as two subcutaneous injections, one month apart. Because of the shortage, some New York, California, the UK and Canada aren’t holding back their supplies — they’re not saving up enough for the second dose. Instead, they choose to vaccinate as many at-risk individuals as possible with their available supply. They hope that more will come in time for the second dose, or that delaying the administration of the second dose will not put people at risk. There is some data from Jynneos that suggests that this strategy will still be effective.

A longer delay between doses gives memory cells more time and a better chance to respond. explained Yale immunologist Akiko Iwasaki Nature that a later booster vaccination is sometimes more effective: “Immunologically speaking, it can even help to delay a little.” Others fear that a longer dosing interval could promote resistance, at least in the case of Covid.

There is another promising approach called dose-sparing or dose-splitting. With HHS only providing 786,000 doses of Jynneos to date, this will be critical. Rather than administering one dose subcutaneously into the fat under the skin, each dose could be divided into five doses administered intradermally or into the skin.

There is data to support this, with an ‘equivalent immune response’ being found between the two different forms of administration of Jynneos.

Intradermal injections of vaccines are not new. They have been used with BCG tuberculosis vaccine, hepatitis B vaccine, yellow fever, rabies and others for decades. The WHO had recommended it for Covid.

There are minor problems with intradermal injections – they require some skill to administer properly. Most healthcare workers have some experience with the technique, having learned how to use TB testing. There is also likely to be more itching and irritation at the injection site. The WHO just held a meeting to prioritize future monkeypox vaccine research. NIAID’s John Beigel addressed the dose-sparing approach. A proposed study is under development.

Concluding on the dose-saving approach, FDA Commissioner Robert Califf said: “We have a very good feeling about the intradermal approach and will probably make a final decision on it in the next few days, in a short amount of time, but for now things are looking good .” Then they would need a “564 statement” for emergency approval, since that route of administration has not yet been approved. Hopefully this will happen quickly, more people will be immunized and those infected can be better tested by accessing Sigas Tecoviramat (TPOXX). So far, the response to the monkeypox pandemic has been abysmal and made a lie about “pandemic preparedness.”