Patients on non-recommended treatment regimens are less likely to achieve viral suppression and more likely to report side effects.
“Nationally representative data on antiretroviral therapy (ART) prescribing practices in the United States and on the effectiveness of guideline-specified ART regimens are sparse. Our research took advantage of the unique surveillance program called the Medical Monitoring Program (MMP) to study the effectiveness of ART therapy in HIV-infected adults receiving medical care in the United States,” according to Yunfeng Tie, PhD, of the consulting firm ICF International in Fairfax, Virginia, who presented her research at IDWeek 2015.
IDWeek 2015 is a joint meeting of the Infectious Diseases Society of America (IDSA), the Society for Healthcare Epidemiology of America (SHEA), the HIV Medicine Association (HIVMA), and the Pediatric Infectious Diseases Society (PIDS).
“Using the latest US antiretroviral therapy (ART) guidelines issued by the Department of Health and Human Services Panel on Antiretroviral Guidelines for Adults and Adolescents, we were able to assess the independent associations between ART regimen categories and outcomes,” explained Tie.
To do this, her research team used data from 18,095 participants in the 2009 through 2012 cycles of the MMP, a nationally representative, population-based surveillance sample of HIV-infected adults receiving medical care in the United States. The MMP collects data every 2 years from a sample of small, medium, and large HIV medical care facilities. It uses medical data from patient records with socioeconomic and behavioral data collected during patient interviews.
Using these data, they calculated the adjusted prevalence ratio (APR) and 95% confidence intervals using a multivariate logistics regression model and determined the association between ART regimens and durable viral suppression, defined as all viral load tests <200 copies/mL in the previous year, self-reported 100% ART dose adherence in the past 3 days, and self-reported ART-related side effects.
In this study, nearly all (92%) of HIV-infected adults were prescribed an ART regimen, and of these, 52% were prescribed recommended regimens. The most commonly used treatment was the combination of efavirenz, tenofovir, and emtricitabine (available in a single pill as Atripla). Overall, 29% were using ART regimens that were not recommended, alternative regimens, or other regimens, and this led to an overall decrease of 2% to 8% in ability to achieve durable viral suppression. However, results were much lower for some regimens, such as was the case for patients taking rilpivirine, tenofovir, and emtricitabine (Complera), with only 52% achieving a durable viral suppression.
The effectiveness of ART therapy largely depends on adherence. In this study, dose adherence was high, at 84%, but this was self-reported over the previous 3 days; those patients who were prescribed other or non-recommended regimens were 3% to 7% less likely to be dose adherent. Overall, 16% of patients reported side effects, and those on other, alternative, or non-recommended ART treatment regimens were between 18% and 29% more likely to report side effects.
Although these real-world data are important to help understand how ART therapies are used outside of the clinical setting, it is important to note that the MMP data have many potential confounding factors, including the use of self reports for adherence and side effects, the inability to distinguish between those who were treatment-naïve versus treatment-experienced, and the inclusion of patients who may have failed previous therapies and are on subsequent second- or third-line treatment regimens. It is important to note that the majority of patients (43%) had been receiving treatment for 10 years or more, and only 5% had recently begun treatment.
Additionally, she noted some patients may have placed on a regimen recommended by guidelines in 2009 that it is no longer considered an approved regimen. Comments from the moderator and audience suggested that this study may not necessarily be reflective of what they and other HIV care providers are seeing in their clinics.
It is important that HIV providers continue to recommend that patients begin early ART treatment of patients using recommended ART regimens because, from these real-world prescribing pattern data, “it was clear that only about one half of patients with HIV were prescribed recommended ART regimens and those patients who were not on recommended regimens were less likely to achieve viral suppression and more likely to report side effects,” she concluded.