What to Start: Selecting a First HIV Regimen
What Is an HIV Regimen?
An HIV regimen is a combination of HIV medicines used to treat HIV infection. HIV treatment (also called antiretroviral therapy or ART) begins with choosing an HIV regimen. People on ART take the HIV medicines in their HIV regimens every day. ART helps people with HIV live longer, healthier lives and reduces the risk of HIV transmission.
There are more than 35 HIV medicines approved by the U.S. Food and Drug Administration (FDA) to treat HIV infection. Some HIV medicines are available in combination (in other words, two or more different HIV medicines combined in one pill).
The U.S. Department of Health and Human Services (HHS) provides guidelines on the use of HIV medicines. In general, the guidelines recommend starting ART with a regimen that includes three HIV medicines from at least two different drug classes.
What Are the HIV Drug Classes?
HIV medicines are grouped into six drug classes according to how they fight HIV. The six drug classes are:
- Non-nucleoside reverse transcriptase inhibitors (NNRTIs)
- Nucleoside reverse transcriptase inhibitors (NRTIs)
- Protease inhibitors (PIs)
- Fusion inhibitors
- CCR5 antagonists
- Integrase strand transfer inhibitors (INSTIs)
In general, a person's first HIV regimen includes two NRTIs plus an INSTI, an NNRTI, or a PI boosted with cobicistat (brand name: Tybost) or ritonavir (brand name: Norvir). Cobicistat or ritonavir increase (boost) the effectiveness of the PI.
Click here to see the AIDS_info_ fact sheet that lists the FDA-approved HIV medicines by drug class.
What Factors Are Considered When Choosing an HIV Regimen?
The choice of HIV medicines to include in an HIV regimen depends on a person's individual needs. When choosing an HIV regimen, people with HIV and their health care providers consider the following factors:
- Other diseases or conditions that the person with HIV may have, such as heart disease or pregnancy.
- Possible side effects of HIV medicines.
- Potential interactions between HIV medicines or between HIV medicines and other medicines the person with HIV is taking.
- Results of drug-resistance testing (and other tests). Drug-resistance testing identifies which, if any, HIV medicines won't be effective against a person's HIV.
- Convenience of the regimen. For example, a regimen that includes two or more HIV medicines combined in one pill is convenient to follow.
- Any issues that can make it difficult to follow an HIV regimen. For example, a busy schedule can make it hard to take HIV medicines consistently every day.
- Cost of HIV medicines.
The HHS guidelines on the use of HIV medicines in adults and adolescents recommend several regimens for people starting ART. The best regimen for a person depends on their individual needs.
How Long Does It Take for ART to Work?
Viral load is the amount of HIV in a person's blood. A main goal of ART is to reduce a person's viral load to an undetectable level. An undetectable viral load means that the level of HIV in the blood is too low to be detected by a viral load test.
Once effective ART is started, it usually takes 3 to 6 months for a person's viral load to reach an undetectable level. Having an undetectable viral load doesn't mean a person's HIV is cured. But although there is still some HIV in the person's body, an undetectable viral load shows that ART is working effectively.
This fact sheet is based on information from the following sources:
- From the Department of Health and Human Services: Guidelines for the Use of Antiretroviral Agents in Adults and Adolescents Living with HIV: Treatment Goals and What to Start: Initial Combination Regimens for the Antiretroviral-Naive Patient
- From the Department of Veterans Affairs: Treatment Decisions
[Note from TheBody: This article was created by AIDSinfo, who last updated it on Jan. 24, 2018. We have cross-posted it with their permission.]