Selection of drug-resistant HIV-1 during the early phase of viral decay is uncommon in treatment-naïve patients initiated on a three- or four-drug antiretroviral regimen including lamivudine

The Genotyping Resistance Profile of the Pol Gene Detected in Blood of Newly Diagnosed HIV-Positive Men Is Durably Archived in the Gut Whatever the Time of Initiation of cART

OBJECTIVE

To evaluate the mutational patterns on the pol gene of the main HIV-1 strain archived in cell genome of 10 chronically infected men according to their clinical and therapeutic history. The genotyping resistance profiles were compared between the first blood plasma available at the time of HIV diagnosis and rectal biopsies and PBMC sampled 1-5 years after the initiation of combined antiretroviral therapy (cART).

METHODS

HIV-1 RNA and cell-associated HIV-1 DNA were quantified by Abbott Real-Time HIV-1 and Generic HIV® DNA cell (Biocentric) assays. The mutations in protease and reverse transcriptase genes were assessed by the Trugene® assay (Siemens). The C2V3 region was amplified to determine the viral tropism.

RESULTS

In 9 patients, slight or no differences were observed between the 3 resistance profiles. Those mostly detected were related to the resistance to nucleos(t)ide (D67N, L210W, T215A, T69D) and nonnucleoside (K103N, V106I, V179I) inhibitors. In 1 rilpivirine-treated patient, the M230I mutation was detected in PBMC. No change of viral tropism was observed between samples.

CONCLUSION

These data suggest that resistance mutations harbored by the main HIV strain in plasma at the time of diagnosis are durably archived in DNA cells whatever the delay between infection and initiation of therapy in patients well controlled by cART.

Low prevalence of transmitted genetic drug resistance in a cohort of HIV infected naïve patients entering antiretroviral treatment programs at two sites in northern South Africa

Infection with drug resistant viruses influences the outcome of antiretroviral therapy (ART). This study was carried out to determine the transmitted genetic drug resistance profile in a cohort of patients prior to initiation of treatment at two treatment sites in northern South Africa. These study sites were among the first to benefit from antiretroviral drugs in this region. Data on HIV drug resistance are also limited in northern South Africa; and resistance testing prior to initiation of treatment is not undertaken. In 2008, 80 protease and 80 reverse transcriptase nucleotide sequences obtained from 80 patients were analyzed for genetic drug resistance using the calibrated population resistance tool for transmitted drug resistance. Viral genetic subtypes were determined by phylogenetic analysis. Two drug resistance mutations (M41L and K103N) were detected in two different patients (2.5%; 95% CI: 0.0077-0.0863). Twenty-three sequences (29%) harbored at least one secondary mutation in the reverse transcriptase gene; while all sequences had at least one minor mutation in the protease gene. Phylogenetic analysis of the protease and reverse transcriptase genes showed that 79 out of 80 viruses were HIV-1 subtype C, and one was an A1/C recombinant. The observations suggest that after 4 and 8 years access to ART in Mankweng and the Bela Bela communities respectively, drug resistance mutations in the naïve population was low. Regular studies are needed to update information on drug resistant viruses in treatment naïve patients to inform better treatment policies.

Reappearance of minority K103N HIV-1 variants after interruption of ART initiated during primary HIV-1 infection

BACKGROUND

In the Zurich Primary HIV infection study (ZPHI), minority drug-resistant HIV-1 variants were detected in some acutely HIV-1-infected patients prior to initiation of early antiretroviral therapy (ART). Here, we investigated the reappearance of minority K103N and M184V HIV-1 variants in these patients who interrupted efficient early ART after 8-27 months according to the study protocol. These mutations are key mutations conferring drug resistance to reverse transcriptase inhibitors and they belong to the most commonly transmitted drug resistance mutations.

METHODOLOGY/PRINCIPAL FINDINGS

Early ART was offered to acutely HIV-1-infected patients enrolled in the longitudinal prospective ZPHI study. Six patients harboring and eleven patients not harboring drug-resistant viruses at low frequencies prior to ART were included in this substudy. Minority K103N and M184V HIV-1 variants were quantified in longitudinal plasma samples after treatment interruption by allele-specific real-time PCR. All 17 patients were infected with HIV-1 subtype B between 04/2003 and 09/2005 and received LPV/r+AZT+3TC during primary HIV-1 infection (PHI). Minority K103N HIV-1 variants reappeared after cessation of ART in two of four patients harboring this variant during PHI and even persisted in one of those patients at frequencies similar to the frequency observed prior to ART (<1%). The K103N mutation did not appear during treatment interruption in any other patient. Minority M184V HIV-1 variants were detected in two patients after ART interruption, one harboring and one not harboring these variants prior to ART.

CONCLUSION

Minority K103N HIV-1 variants, present in acutely HIV-1 infected patients prior to early ART, can reappear and persist after interruption of suppressive ART containing two nucleoside/nucleotide analogue reverse transcriptase inhibitors and a ritonavir-boosted protease inhibitor.

TRIAL REGISTRATION

Clinicaltrials.gov NCT00537966.