PrEP or pre-exposure prophylaxis used with antiretroviral drugs has gained a lot of momentum in the community in the last several years, with many of them showing a significant decrease in the risk of catching HIV from a person with the disease. PrEP is available in Scotland and trials are going on in England.
This new trial, however, explores a new way of protecting oneself from HIV that doesn’t include pills. The implant would slowly release the PrEP drug, which means people would not have to worry about taking a pill each day. It’s similar to the birth control implant, which is a long-acting contraceptive that is often known as “fit and forget.”
MSD, the pharmaceutical company that came up with the implant, is conducting its first PrEP implant in humans’ trial. The company tested the implant on animals initially.
To date, 12 healthy adults were implanted for 12 weeks with either a 54mg or 62mg dose of islatravir. Four participants were given a placebo implant. 14 of the 16 participants were men.
Researchers were looking at how well the participants were able to tolerate the implant and the concentration of islatrvir and its active form during the trial and after the implant was removed after four weeks.
Although it’s a small trial, the results showed the participants handled the implant well. Data about the drug concentration found the implants could last up to a minimum of eight months on the lower-dose device and up to a year on the higher-dose one.
MSD researcher Randy Matthews said the results reinforced the notion that additional clinical development is necessary. He said other trials could look at the implants at varying doses and makeup composition. The trials could include examinations in a larger group of people.
As for cost, this is unknown as it’s still in its infancy.
Dr. Timothy Hildebrandt of London School of Economics carried out public perception research on PrEP and said this trial could help alleviate doctors’ fears of patients not talking pills, address the difficulties of taking pills and giving people a more private way to use PrEP.
He said the trial looks to provide a long-term alternative PrEP delivery system that could rival the pills. Hildebrandt said researchers learned from the contraceptive idea that offers an array of delivery options could increase the number of people who use the drug.
University College of London Clinical Epidemiology professor Sheena McCormack led the PrEP trials and said the implant development was outstanding. She said while pills were fine in places like the UK and U.S., in areas such as sub-Saharan Africa, it wasn’t always feasible.
McCormack said using the implant was far more likely in these places. She said provider skills are going to be enacted when the product becomes readily available. She said the PrEP implant has a real future.
Written by Mark Riegel, MD
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