title: Frequent Cross-Resistance to Dapivirine in HIV-1 Subtype C-Infected Individuals after First-Line Antiretroviral Therapy Failure in South Africa.
abstract: A vaginal ring containing dapivirine (DPV) has shown moderate protective efficacy against HIV-1 acquisition, but the activity of DPV against efavirenz (EFV)- and nevirapine (NVP)-resistant viruses that could be transmitted is not well defined. We investigated DPV cross-resistance of subtype C HIV-1 from individuals on failing NVP- or EFV-containing antiretroviral therapy (ART) in South Africa. Plasma samples were obtained from individuals with >10,000 copies of HIV RNA/ml and with HIV-1 containing at least one non-nucleoside reverse transcriptase (NNRTI) mutation. Susceptibility to NVP, EFV, and DPV in TZM-bl cells was determined for recombinant HIV-1LAIcontaining bulk-amplified, plasma-derived, full-length reverse transcriptase sequences. Fold change (FC) values were calculated compared with a composite 50% inhibitory concentration (IC50) from 12 recombinant subtype C HIV-1LAIplasma-derived viruses from treatment-naive individuals in South Africa. A total of 25/100 (25%) samples showed >500-FCs to DPV compared to treatment-naive samples with IC50s exceeding the maximum DPV concentration tested (132 ng/ml). A total of 66/100 (66%) samples displayed 3- to 306-FCs, with a median IC50of 17.6 ng/ml. Only 9/100 (9%) samples were susceptible to DPV (FC < 3). Mutations L100I and K103N were significantly more frequent in samples with >500-fold resistance to DPV compared to samples with a ≤500-fold resistance. A total of 91% of samples with NNRTI-resistant HIV-1 from individuals on failing first-line ART in South Africa exhibited ≥3-fold cross-resistance to DPV. This level of resistance exceeds expected plasma concentrations, but very high genital tract DPV concentrations from DPV ring use could block viral replication. It is critically important to assess the frequency of transmitted and selected DPV resistance in individuals using the DPV ring.
authors.affiliation: University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Kerri J
authors.initials: KJ
authors.lastname: Penrose
authors.affiliation: BARC-SA and Lancet Laboratories, Johannesburg, South Africa.
authors.forename: Carole L
authors.initials: CL
authors.lastname: Wallis
authors.affiliation: BC Centre for Excellence in HIV/AIDS, Vancouver, British Columbia, Canada.
authors.forename: Chanson J
authors.initials: CJ
authors.lastname: Brumme
authors.affiliation: University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Kristen A
authors.initials: KA
authors.lastname: Hamanishi
authors.affiliation: University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Kelley C
authors.initials: KC
authors.lastname: Gordon
authors.affiliation: BARC-SA and Lancet Laboratories, Johannesburg, South Africa.
authors.forename: Raquel V
authors.initials: RV
authors.lastname: Viana
authors.affiliation: BC Centre for Excellence in HIV/AIDS, Vancouver, British Columbia, Canada.
authors.forename: P Richard
authors.initials: PR
authors.lastname: Harrigan
authors.affiliation: University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: John W
authors.initials: JW
authors.lastname: Mellors
authors.affiliation: University of Pittsburgh, Pittsburgh, Pennsylvania, USA ump3@pitt.edu.
authors.forename: Urvi M
authors.initials: UM
authors.lastname: Parikh
mesh_terms: D019380:Anti-HIV Agents / Q000494:pharmacology*; D024921:Drug Resistance, Multiple, Viral / Q000187:drug effects* / Q000235:genetics; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000821:virology; D054303:HIV Reverse Transcriptase / Q000235:genetics; D015497:HIV-1 / Q000187:drug effects* / Q000235:genetics* / Q000472:pathogenicity; D006801:Humans; D020128:Inhibitory Concentration 50; D009154:Mutation; D011743:Pyrimidines / Q000097:blood / Q000494:pharmacology*; D013019:South Africa; D017211:Treatment Failure; D014621:Vagina / Q000821:virology
chemical_list: D019380:Anti-HIV Agents; D011743:Pyrimidines; C514824:reverse transcriptase, Human immunodeficiency virus 1; D054303:HIV Reverse Transcriptase; C481671:Dapivirine
keywords: HIV-1; NNRTI; antiretroviral therapy; cross-resistance; dapivirine; drug resistance; human immunodeficiency virus; non-nucleoside reverse transcriptase inhibitor