Descovy & Truvada: The Two Faces of Preexposure Prophylaxis (PrEP)
By Jonathan Lucero McKinney
An estimated 1.2 million individuals at risk of HIV infection stand to benefit from daily preexposure prophylaxis or PrEP. We’ve covered it before at Options, and it’s likely you’ve already heard about PrEP, but did you know that there are now 2 FDA-approved drugs for PrEP? Yes, those at risk of HIV can choose from the well-established Truvada or the newcomer, Descovy. The pharmaceutical company Gilead makes both of these drugs, and they have recently released results from their DISCOVER trial which investigated the two drugs side-by-side in a 96-week study of nearly 5,500 participants. In the fight against HIV, the more options at our disposal, the better. But what are the real similarities and differences between these PrEP options?
To start, if you think that Truvada or Descovy are right for you, it’s important to begin with an open conversation with a medical professional. You’ll need to determine your level of risk and make sure that you’re HIV-negative before taking PrEP of any kind. Many sexually active men and women as well as those who use IV drugs stand to benefit from a PrEP regimen. Be mindful to let your provider know about any possible recent exposures and any symptoms of fever or recent fatigue. This is important because people with HIV often do not know they have it, and testing in the early stages of acquiring HIV can miss the virus altogether. Your provider will know the steps to take if this is happening to you; the most important thing is to be open and honest.
"We know it can sometimes be difficult for people to be honest with their healthcare providers about their sex lives, and we also know that some providers don't know enough about PrEP, or have shamed their patients for seeking it out," says Mikel Wadewitz, director of AIDS Project Rhode Island. "If a provider says they don't know about PrEP or you feel they are judgmental, get another provider. That's your right and it's good for your health. You can use resources such as PleasePrEPMe.org to find a PrEP provider."
Both Truvada and Descovy are tablets taken once daily. PrEP adherence has long been a factor that directly correlates to the drug’s effectiveness. Those who adhere to the daily prescription show extremely high rates of HIV-prevention, as much as 99% in some studies. Whether it’s Truvada or Descovy, if you forget to take your medication, you reduce the drug’s ability to work. Longer-acting PrEP options are currently being researched, but none are yet available to the public. Descovy tablets are a bit smaller than Truvada, so they may be better for those who have difficulty taking pills by mouth.
Dr. Philip Chan, Medical Director of Open Door Health, comments, "I am also looking forward to the next generation of PrEP medications which are (hopefully) long-acting and come in different formulations for people."
Dosing around the time of sexual activity, or “on-demand dosing,” has been endorsed by the World Health Organization and the San Francisco Public Health Department, but hasn’t gained support by the FDA just yet. An 86% reduction in HIV-infection has been observed when dosing this way, though this has only been studied with Truvada in men having sex with men, it goes like this: Take two pills together roughly 2-24 hours before sex, then one pill 24 hours after sex, and a final pill after another 24 hours. It’s also called 2-1-1 dosing, and it should be noted that if you continue having sex, you should continue taking a tablet every day until two sexless days have passed. Descovy has not been studied in “on-demand dosing” and shouldn’t be taken this way. Instead, for those taking Truvada, this dosing strategy could be a great option for those who can’t commit to daily dosing regardless of sexual activity.
Testing and monitoring while on Truvada or Descovy is generally the same. You’ll likely be screened for HIV and STIs every three months (some doctors prefer 6-month screenings), and blood work will be needed to determine how the medication is affecting your kidney function. It turns out that STIs are very prevalent in people taking PrEP -- well over 50%. You need to remember to combine PrEP with other risk-reduction strategies, such as condom use.
From the DISCOVER trial, there are some key differences that have been concluded between the two PrEP options. The first is that Descovy is not yet recommended for those at risk of HIV through vaginal sex. It has not been studied in this population, but Gilead will continue looking into the efficacy of their new drug for this type of transmission.
Another difference is that Descovy has demonstrated a lower risk-profile for kidney and bone issues, two adverse effects that Truvada has often been criticized for. Descovy is approved for people with lower kidney function, and the DISCOVER trial resulted in significantly fewer kidney impairments measured in Descovy relative to Truvada. Bone mineral density, essentially a measure of how well your bones are formed, had a larger decline in Truvada patients over Descovy patients.
Throughout the 96-week study, the two drugs closely compare to one another in showing no significant differences in their ability to prevent HIV-infection. On average, Truvada resulted in less weight gain than Descovy, 1.1 lbs vs. 3.7 lbs respectively. Descovy patients also had greater increases in cholesterol levels.
Does this mean that people looking into PrEP for the first time should jump to Descovy, and those on Truvada should switch? The answer is mostly no on both accounts. Even though Descovy shows lower risk for kidney and bone issues, the results weren’t clinically significant. Generally speaking, people taking Truvada aren’t dropping from kidney failure or keeling over from fragile bones that easily fracture. Descovy may be the choice if you have known kidney disease or at high risk of osteoporosis, but right now the research and provider comfort is in Truvada’s corner.
“Regardless of which medication people choose for PrEP, they should take it daily to prevent HIV. Both medications are generally well-tolerated and effective”, adds Dr. Philip Chan.
Cost is also a big player. Truvada is scheduled to become generic in September 2020, which means that it could become far cheaper. Currently, the cost of both medications is around $2,000 for a monthly supply, however, expanded Medicaid coverage and financial assistance options through Gilead and other sources could significantly reduce the cost of PrEP, even making it free to the patient. When Truvada becomes generic, the price will likely drop and coverage should expand greater than newly minted Descovy. In fact, a study by the Annals of Internal Medicine published in May of 2020 concluded that a modest reduction in adverse effects seen in Descovy is not worth the premium price that Gilead is asking.
Research is moving forward and the fight to end the HIV epidemic by 2030 is heading in a good direction. Having this knowledge ahead of a discussion with your provider can help simplify the decision on which medication to prescribe. Know the facts; be open with your provider; and do what you can to make health decisions that are right for you.
Be sure to check out the video that the author, Jonathan Lucero McKinney, has posted on YouTube. https://youtu.be/sOxYy2f0noE