ART prescribing patterns evolve over past decade
Research, experience have winnowed down choices
Research has found that combination antiretroviral therapies and studies showing superior benefits of some drugs over others have led to wide acceptance in recent years for two initial therapy regimens.
Three to 10 years ago, there were more than a dozen initial therapies prescribed by HIV clinicians. Now there are two.1
One of the chief factors in the change is the success of combination medications, and especially the success of one particular combination: emtricitabine (Emtriva®)/tenofovir (Viread®), which is called Truvada®, says James Alexander McKinnell, MD, a fellow in infectious diseases at the University of Alabama at Birmingham, AL.
For a short period, another drug combining lamivudine and zidovudine, called Combivir® was widely prescribed, he notes.
"Some studies have compared Truvada with Combivir, and patients on Truvada did better," McKinnell explains. "Those results were published in 2004, and if you look at our study's treatment share graph, you will see HIV physicians stopped prescribing Combivir after that."
Combivir had been one of the most popular combination drugs, and in a couple of years it was gone, McKinnell says.
The study's chief limitation is that many of the ART regimens were crafted before resistance testing was widely available, McKinnell says.
"We could not measure the impact of resistance of ART in my study," he says. "But the vast majority of patients do not have much resistance."
McKinnell and co-investigators took their analysis one step further, looking at what happened to HIV patients after they began the initial ART. They looked at how many patients changed regimens and what happened after they changed.
The study found that many patients started on initial therapy soon need to have their ARTs changed, and the medications used in the second-line treatment varied widely.
Patients with stable initial treatment, but many other medical issues, could benefit from care by a general practitioner, in addition to their care at an HIV clinic, he adds.
"We found very quickly that many needed to change therapy because of side effects or virological failure," he says. "We found that the simplification of the first regimen doesn't continue."
For instance, if a patient was started on a lamivudine/zidovudine combination medication that began to fail, then they were not necessarily switched to the emtricitabine/tenofovir combination pill, McKinnell says.
"There was tremendous variability there, and we looked across a whole spectrum of patients," he adds. "Forty-three percent of patients needed a second regimen over the course of the 2000 to 2007 time period of the study."
Reference
- McKinnell JA, Willig JH, Westfall AO, et al. Contemporary antiretroviral therapy: Is it time for the generalist to return? Poster presented at the 48th Annual ICAAC/IDSA 46th Annual Meeting, held Oct. 25-28, 2008, in Washington, DC. Poster:H-1260.
You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
- Award-winning Medical Content
- Latest Advances & Development in Medicine
- Unbiased Content