Open bottle of prescription PrEP Pills for Pre-Exposure Prophylaxis to help protect people from HIV.
We find ourselves in a particularly challenging stage of the pandemic. While proving to be effective at reducing hospitalizations, and severe disease, our best vaccines have failed to protect against infection. While Paxlovid has been an effective line of defense in treating breakthrough Covid-19 infections of those most critically at risk, we are yet to explore the potential of prophylactic drugs.
Prevention is always better than a cure. Especially when more than one-third of Covid-19 patients will develop long-term symptoms and some will experience symptoms severe enough to be disabling for many months, if not years.
HIV is another infectious disease that has eluded an effective vaccine, but after many years of research and investment in drug development it is no longer a death sentence. I have long advocated that drug developers should take a lesson from HIV research and focus on developing combinations of small-molecule antiviral drugs to prevent and treat Covid-19.
However, it is not enough to just to focus on the development of prophylactic drugs. The drugs will be rendered ineffective if there is hesitancy around taking the drugs or low levels of adherence to medication regimens. With each global health crisis it becomes clear that we need both medical solutions and the public health orientated behavioral and social change programs to implement them. Policy makers and public health officials need to work with social scientists to create education and outreach initiatives and restore trust in institutions. We also need to ensure equity and access to preventative treatments particularly in healthcare deserts and low socioeconomic areas. No population is safe until we all are.
A recent study, on the real world effectiveness of pre-exposure prophylaxis in men at high risk of HIV infection in France demonstrates how even a highly effective drug such as PrEP can be weakened by a lack of medication regime adherence.
Pre-exposure prophylaxis (PrEP) for HIV has shown to be highly effective in clinical trials, but there is less research on the effectiveness when prescribed in real life to diverse populations. The authors of this study used a matched, nested case-control study among adult men at high risk of HIV infection between Jan 1, 2016, and June 30, 2020, with data from the French national health data system. Men who were newly diagnosed with HIV infection before Dec 31, 2020, were individually matched with up to five controls for age, socioeconomic status, place of residence, calendar year, and follow-up duration.
Among a total of 46 706 individuals, 256 patients with HIV infection were identified and matched with 1213 controls. PrEP users accounted for 29% of cases and 49% of controls. Real world PrEP effectiveness was found to be 60% overall, expanding to 93% for a high amount of PrEP consumption, and 86% if excluding periods after PrEP discontinuation.
PrEP effectiveness was significantly reduced in people younger than 30 years and in those with low socioeconomic circumstances. Both groups showed low amounts of PrEP consumption and high rates of PrEP discontinuation.
While this study demonstrates that PrEP effectiveness appears to be lower in real-world conditions than is reported in clinical trials. Lower effectiveness appears to be linked to compliance. Strengthening efforts to improve the monitoring of PrEP compliance is essential to ensure PrEP higher effectiveness in a real world setting.