Key Clinical Updates in HIV Infection & AIDS: Treatment
In the ANCHOR study, which involved nearly 4500 individuals with anal high-grade squamous intraepithelial lesions (HGSIL), nine patients who were assigned to aggressive therapy (mostly office-based electrocautery) developed anal cancer compared with 21 of those in an active monitoring group, representing a 57% decrease in relative risk over the median 25.8-month follow-up period. This pivotal study will change care toward more aggressive screening for HGSIL and treatment to prevent progression to anal cancer.
Cabotegravir was FDA-approved for use as preexposure prophylaxis as an injectable medication, every 8 weeks. This medication has been shown to be superior to oral tenofovir disoproxil fumarate/emtricitabine in preventing HIV infection among men who have sex with men, transgender women who have sex with men, and cisgender women in sub-Saharan Africa.
Prophylaxis against Mycobacterium avium complex is no longer recommended in most individuals who are initiating antiretroviral therapy (ART), including in those with CD4+ counts less than 50 cells/mcL. The incidence of M avium complex infection is very low among those on ART.
The TEMPRANO trial showed that individuals immediately initiating ART versus delaying treatment for CD4 count to fall below 500 cells/mcL had lower rates of severe illness.
Palefsky J et al. CROI 2022 (special session).
Treatment for HIV infection can be broadly divided into the following categories: (1) prophylaxis for opportunistic infections, malignancies, and other complications of HIV infection; (2) treatment of opportunistic infections, malignancies, and other complications of HIV infection; and (3) treatment of the HIV infection itself with ART.
A. Prophylaxis for Complications of HIV Infection
In general, decisions about prophylaxis of opportunistic infections are based on the CD4 count, recent HIV viral load, and a history of having had the infection in the past. In the era prior to ART, patients who started taking prophylactic regimens were maintained on them indefinitely. However, studies have shown that in patients with robust improvements in immune function—as measured by increases in CD4 counts above the levels that are used to initiate treatment—prophylactic regimens can safely be discontinued.
Because individuals living with advanced HIV infection are susceptible to a number of opportunistic pathogens, the use of agents with activity against more than one pathogen is preferable. It has been shown, for example, that trimethoprim-sulfamethoxazole confers protection against toxoplasmosis in individuals receiving this medication for Pneumocystis prophylaxis.
1. Prophylaxis against Pneumocystis pneumonia
Patients with CD4 counts below 200 cells/mcL, a CD4 lymphocyte percentage below 14%, or oral candidiasis should be offered primary prophylaxis for Pneumocystis pneumonia. Patients with a history of Pneumocystis pneumonia should receive secondary prophylaxis until their viral load is undetectable and they have maintained a CD4 count of 200 cells/mcL or more while receiving ART for longer than 3 months. Regimens for Pneumocystis prophylaxis are given in Table 31–6.