From the Guidelines
A very low Human Immunodeficiency Virus (HIV) viral load is considered to be below 50 copies/mL. Changes to Antiretroviral Therapy (ART) medications should be made when the HIV RNA level is above 200 copies/mL on at least two consecutive tests, indicating virologic failure 1.
Key Considerations
- Viral load monitoring: HIV RNA testing should be performed every 3-4 months to evaluate the continuing effectiveness of therapy 1.
- Virologic failure: Defined as HIV RNA level above 200 copies/mL on at least two consecutive tests, prompting a change in therapy 1.
- Therapy initiation: Antiretroviral therapy should be initiated after the first viral load measurement is obtained, especially in patients with advanced HIV disease 1.
- Resistance testing: Should be performed to guide the selection of a new regimen when a patient is on a failing regimen 1.
ART Regimen Considerations
- First-line treatment: The current recommended first line of treatment is a NNRTI, such as efavirenz, with a nucleoside backbone like Truvada® (emtricitabine and tenofovir disoproxil fumarate) 1.
- Regimen changes: Single drug switches are not recommended and should only be done when the patient has achieved and maintained optimal viral suppression (i.e., plasma HIV viral load of < 50 copies/mL) 1.
- New regimen selection: Should contain at least two and preferably three active drugs for patients to obtain optimal results 1.
From the Research
Definition of Very Low HIV Viral Load
- A very low HIV viral load is typically considered to be below 50 copies/mL 2
- Some studies define low-level viremia (LLV) as a viral load between 50 and 999 copies/mL 3, 4, 5
- Very-low-level viremia (VLLV) is a relatively new concept, defined as a viral load between 20 and 50 copies/mL 2
Management of Low-Level Viremia
- The goal of antiretroviral therapy (ART) is to maintain a suppressed HIV viral load below limits of assay detection 3
- Persistent LLV, especially between 50 and 200 copies/mL, is associated with an increased risk of virologic failure 3
- Changes to ART medications may be considered when viral loads remain in LLV, especially if the patient is experiencing virologic failure 3, 5
- However, some studies suggest that VLLV does not necessarily predict virologic failure and should not prompt more frequent clinic visits or antiretroviral regimen changes 2
Threshold for Changes to ART Medications
- The threshold at which LLV becomes predictive of disease progression varies between studies, but evidence suggests that incomplete viral suppression leads to the accumulation of resistance mutations and increased risk of virologic progression 5
- Some studies suggest that a viral load above 1000 copies/mL is a threshold for considering changes to ART medications 6
- However, other studies suggest that even lower levels of viremia, such as 50-199 copies/mL, may be associated with an increased risk of virologic failure and may require changes to ART medications 3