Following San Francisco Department of Public Health integrating PrEP “on-demand” as a guideline in February, New York City has also signed on board. The method of taking preventative HIV medication specifically around sexual encounters, also called PrEP 2-1-1, is still not approved by the Food and Drug Administration or the Center of Disease Control.
“We wanted to say that this is evidence based and safe — and providers don't have to guess if they don't know,” Dr Demetre, the deputy commissioner for Division of Disease Control at the New York City Department of Health and Mental Hygiene told The Body about the new guidelines. “We want to make sure they have guidance to do this right.”
While many users of PrEP take the medication daily in order to prevent seroconversion, this data-backed “event-driven” method provides an alternative. Having been tested in multiple studies, PrEP “on demand” requires adherents to take two doses of the medication 2 - 24 hours before sex, and then one pill 24 hours after that dose, and one 24 hours after that. For those who continue to have sex while taking the medicine, they should continue take PrEP daily until they’ve taken it for 48 hours after their last encounter. This system is only effective for anal and oral sex between men.
The particular method drew some criticism in March when a patient using the method seroconverted in Australia. He was the seventh reported case of seroconversion while on PrEP, but was the first reported to happen while utilizing “on demand.” Some speculated that this pointed to the ineffectiveness of intermittently taking the medication but in the interim results of the Prevenir study, “on-demand” was proven to be as effective as daily PrEP.
“Right now, the US guideline says daily PrEP is the way to go but the reality is, for some people, daily PrEP isn’t an option whether because they don’t want to take a pill a day or they want to minimize exposure to the drug, Demetre told us at the time of the criticism. “From the scientific perspective, [on demand is] 100% feasible. 100% data supported.” According to the NYC Department of Health, taking two PrEP pills brings medicine levels in the colorectal tissues up to “target levels” 98% of the time within 24 hours.
While taking PrEP as a part of a daily regimen is still advised, “on demand” may be a better fit for some New Yorkers for a variety of reasons. It provides a less expensive alternative as the medication would be refilled less — patients are still encouraged to go in for checkups every three months. It also can provide a preferred option for those who have medical concerns with daily PrEP.
Still, PrEP “on demand” is not for everyone as it requires adherents to know they are going to have sex, hours before. PrEP, in all forms, should be used with a condom to prevent other STIs.
All PrEP users should consult their providers on which regimen is best for them.