The Food and Drug Administration is considering splitting doses of the Jynneos vaccine into fifths to increase supply amid the expanding monkeypox outbreak, FDA Commissioner Robert Califf said this week.

Driving the news: Under the "dose-sparing" approach, health care providers could use one vial of the vaccine to administer up to five doses without an impact on safety or efficacy, Califf said.

• As the Department of Health and Human Services works with Jynneos' manufacturer to increase the availability of the vaccine, Califf said "dose-sparing" could provide a potential solution in the interim.

Between the lines: The new approach would require a different method of administration, or injection into the skin, Califf said at a briefing on Thursday.

• The Jynneos vaccine currently is administered with a subcutaneous injection, which goes into the fat layer underneath the skin.
• The new "dose-sparing" approach would require intradermal administration, which goes into the dermis. The dermis lies just underneath the top layer of skin known as the epidermis.
• Califf noted that there are some advantages to this approach, such as an improved immune response to the vaccine.

What he's saying: "It's important to note that the overall safety and efficacy profile will not be sacrificed with this approach," Califf said. "Please know we've been exploring all scientifically feasible options, and we believe this could be a promising approach."

• "It's important to note that we will not be sacrificing the high-quality regulatory standards that Americans have come to expect," he added.