Genital Shedding of Human Immunodeficiency Virus Type-1 (HIV) When Antiretroviral Therapy Suppresses HIV Replication in the Plasma

Impact of Switching to Long-Acting Injectable Cabotegravir Plus Rilpivirine on Rectal HIV-1 RNA Shedding and Implications for Transmission Risk

BACKGROUND

The impact of long-acting injectable cabotegravir plus rilpivirine (CAB/RPV) on rectal human immunodeficiency virus 1 (HIV-1) RNA dynamics and the factors associated with viral shedding remain poorly understood.

METHODS

This prospective study evaluated HIV-1 RNA dynamics by analyzing sequential paired plasma and rectal fluid samples from virologically suppressed individuals who transitioned from oral antiretroviral therapy (ART) to every-2-month CAB/RPV (preceded or not by oral lead-in), over a 9-month follow-up period. RPV trough concentrations were measured in 384 rectal samples.

RESULTS

In total, 597 plasma and 561 rectal samples from 90 participants were analyzed. HIV-1 RNA >50 (>1.69 log10) copies/swab was detected in 14.7% (59/401) of rectal samples (42.2% of participants) during intramuscular CAB/RPV, and in 17.5% (28/160) of rectal samples (29% of participants) during oral ART. Median detectable rectal HIV-1 RNA level during intramuscular ART was 362 (range, 133-2216) copies/swab. The frequency and quantity of rectal shedding did not differ between groups with/without oral lead-in. No correlation was observed between rectal shedding and detectable plasma HIV-1 RNA. Median rectal RPV concentration was 3.07 (quartile 1-quartile 3, 2.83-3.35) log10 ng/swab, 1.6-fold above the 90% maximum effective concentration (EC90) for rectal tissue, and did not correlate with rectal HIV-1 RNA levels. Rectal shedding was associated with plasma pre-ART HIV-1 RNA >5 log10 in multivariate Cox regression, but was unrelated to established predictors of virological failure with CAB/RPV.

CONCLUSIONS

Rectal HIV-1 shedding is common during bimonthly intramuscular CAB/RPV treatment and is also observed with oral ART. Shedding was independent of concurrent plasma HIV-1 RNA and rectal RPV concentrations, and was associated with pre-ART viral load.

Genome sequences of human anelloviruses in the Lamedtorquevirus, Memtorquevirus, and Samektorquevirus genera identified from the female genital tract

We identified and characterized seven anellovirus genome sequences in the female genital tract through virome metagenomic sequencing of cervicovaginal lavage specimens from women living with HIV in Peru. Phylogenetic and genomic analyses indicate that they belong to three newly proposed Lamedtorquevirus, Memtorquevirus, and Samektorquevirus genera in the Anelloviridae family.

Longitudinal cervicovaginal microbiome and virome alterations during ART and discordant shedding in women living with HIV

Despite successful suppression of plasma HIV replication by antiretroviral therapy (ART), some women living with HIV (WLHIV) can still experience genital HIV shedding (discordant shedding). Female genital tract (FGT) microbiome and virome dynamics during long-term ART in WLHIV are poorly understood but might contribute to discordant HIV shedding, as the microbiome and virome are known to influence FGT health. To understand FGT microbial communities over time during ART usage and discordant shedding, we characterized the microbiome and virome in 125 cervicovaginal specimens collected over two years in 31 WLHIV in Lima, Peru. Intrapersonal bacterial microbiome variation was higher in HIV shedders compared to non-shedders. Cervicovaginal virome composition changed over time, particularly in non-shedders. Specifically, anellovirus relative abundance was inversely associated with ART duration and CD4 counts. Our results suggest that discordant HIV shedding is associated with FGT microbiome instability, and immune recovery during ART influences FGT virome composition.

Pregnancy Management in HIV Viral Controllers: Twenty Years of Experience

(1) Background: The evidence base for the management of spontaneous viral controllers in pregnancy is lacking. We describe the management outcomes of pregnancies in a series of UK women with spontaneous HIV viral control (<100 copies/mL 2 occasions before or after pregnancy off ART). (2) Methods: A multi-centre, retrospective case series (1999-2021) comparing pre- and post-2012 when guidelines departed from zidovudine-monotherapy (ZDVm) as a first-line option. Demographic, virologic, obstetric and neonatal information were anonymised, collated and analysed in SPSS. (3) Results: A total of 49 live births were recorded in 29 women, 35 pre-2012 and 14 post. HIV infection was more commonly diagnosed in first reported pregnancy pre-2012 (15/35) compared to post (2/14), p = 0.10. Pre-2012 pregnancies were predominantly managed with ZDVm (28/35) with pre-labour caesarean section (PLCS) (24/35). Post-2012 4/14 received ZDVm and 10/14 triple ART, p = 0.002. Post-2012 mode of delivery was varied (5 vaginal, 6 PLCS and 3 emergency CS). No intrapartum ZDV infusions were given post-2012 compared to 11/35 deliveries pre-2012. During pregnancy, HIV was detected (> 50 copies/mL) in 14/49 pregnancies (29%) (median 92, range 51-6084). Neonatal ZDV post-exposure prophylaxis was recorded for 45/49 infants. No transmissions were reported. (4) Conclusion: UK practice has been influenced by the change in guidelines, but this has had little impact on CS rates.

EFdA efficiently suppresses HIV replication in the male genital tract and prevents penile HIV acquisition

Sexually transmitted HIV infections in heterosexual men are acquired through the penis. Low adherence to condom usage and the fact that 40% of circumcised men are not protected indicate the need for additional prevention strategies. Here, we describe a new approach to evaluate the prevention of penile HIV transmission. We demonstrated that the entire male genital tract (MGT) of bone marrow/liver/thymus (BLT) humanized mice is repopulated with human T and myeloid cells. The majority of the human T cells in the MGT express CD4 and CCR5. Direct penile exposure to HIV leads to systemic infection including all tissues of the MGT. HIV replication throughout the MGT was reduced 100-1,000-fold by treatment with 4'-ethynyl-2-fluoro-2'-deoxyadenosine (EFdA), resulting in the restoration of CD4+ T cell levels. Importantly, systemic preexposure prophylaxis with EFdA effectively protects from penile HIV acquisition. IMPORTANCE Over 84.2 million people have been infected by the human immunodeficiency virus type 1 (HIV-1) during the past 40 years, most through sexual transmission. Men comprise approximately half of the HIV-infected population worldwide. Sexually transmitted HIV infections in exclusively heterosexual men are acquired through the penis. However, direct evaluation of HIV infection throughout the human male genital tract (MGT) is not possible. Here, we developed a new in vivo model that permits, for the first time, the detail analysis of HIV infection. Using BLT humanized mice, we showed that productive HIV infection occurs throughout the entire MGT and induces a dramatic reduction in human CD4 T cells compromising immune responses in this organ. Antiretroviral treatment with novel drug EFdA suppresses HIV replication in all tissues of the MGT, restores normal levels of CD4 T cells and is highly efficient at preventing penile transmission.

Human Immunodeficiency Virus Type 1 RNA Genital Tract Shedding After Cryotherapy for Cervical Intraepithelial Neoplasia in Western Kenya

This prospective study of 39 women living with human immunodeficiency virus (HIV) on antiretroviral therapy in Western Kenya aimed to quantify genital tract HIV-1 RNA (GT-HIV RNA) shedding before and after cryotherapy for cervical intraepithelial neoplasia. Most GT-HIV RNA shedding was detected precryotherapy, suggesting that cryotherapy was not the primary cause of shedding.

HIV drug resistance in various body compartments

PURPOSE OF REVIEW

HIV drug resistance testing using blood plasma or dried blood spots forms part of international guidelines. However, as the clinical utility of assessing drug resistance in other body compartments is less well established, we review this for blood cells and samples from other body compartments.

RECENT EVIDENCE

Although clinical benefit is not clear, drug resistance testing in blood cells is often performed when patients with suppressed plasma viral loads require a treatment substitution. In patients with HIV neurocognitive disease, cerebral spinal fluid (CSF) drug resistance is rarely discordant with plasma but has nevertheless been used to guide antiretroviral drug substitutions. Cases with HIV drug resistance in genital fluids have been documented but this does not appear to indicate transmission risk when blood plasma viral loads are suppressed.

SUMMARY

Drug-resistant variants, which may be selected in tissues under conditions of variable adherence and drug penetration, appear to disseminate quickly, and become detectable in blood. This may explain why drug resistance discordance between plasma and these compartments is rarely found. Partial compartmentalization of HIV populations is well established for the CSF and the genital tract but other than blood plasma, evidence is lacking to support drug resistance testing in body compartments.

Brief Report: Vaginal Viral Shedding With Undetectable Plasma HIV Viral Load in Pregnant Women Receiving 2 Different Antiretroviral Regimens: A Randomized Clinical Trial

BACKGROUND

Pregnant women using antiretrovirals (ARVs) may have persistent vaginal viral shedding, which could be associated with sexual and perinatal HIV transmission. However, there are scant data on vaginal viral load (VVL) in pregnant women with undetectable plasma viral load (PVL).

METHODS

This study was a post hoc analysis of an open-label randomized trial to evaluate the virologic response of 2 ART regimens. The participants were ART-naive women living with HIV initiating ART regimens between 20 and 36 weeks of pregnancy recruited at 19 clinical sites in 6 countries. Participants were randomized to receive 400 mg of raltegravir 2 times a day or 600 mg of efavirenz 4 times a day in addition to 150 mg of lamivudine and 300 mg of zidovudine 2 times a day. VVL and PVL tests were performed at every study visit. The primary outcome measures were HIV-1 PVL and VVL at maternal study week 4 and rates of perinatal HIV transmission.

RESULTS

A total of 408 were enrolled, of whom 323 had VVL samples 4 weeks after enrollment and were included in this analysis. Among women with undetectable/nonquantifiable PVL during ART, the overall rate of quantifiable VVL at week 4 was 2.54% (7/275). Of the 275 with nonquantifiable PVL, 99.1% (115/116) and 96.2% (153/159) had nonquantifiable VVL in the efavirenz and raltegravir arms, respectively. None of the 7 women with quantifiable VVL at the week 4 study visit transmitted HIV to their infants.

CONCLUSIONS

Detectable VVL in pregnant women with undetectable/nonquantifiable PVL while receiving ART was rare and not associated with perinatal HIV transmission.

A highly multiplexed droplet digital PCR assay to measure the intact HIV-1 proviral reservoir

Quantifying the replication-competent HIV reservoir is essential for evaluating curative strategies. Viral outgrowth assays (VOAs) underestimate the reservoir because they fail to induce all replication-competent proviruses. Single- or double-region HIV DNA assays overestimate it because they fail to exclude many defective proviruses. We designed two triplex droplet digital PCR assays, each with 2 unique targets and 1 in common, and normalize the results to PCR-based T cell counts. Both HIV assays are specific, sensitive, and reproducible. Together, they estimate the number of proviruses containing all five primer-probe regions. Our 5-target results are on average 12.1-fold higher than and correlate with paired quantitative VOA (Spearman's ρ = 0.48) but estimate a markedly smaller reservoir than previous DNA assays. In patients on antiretroviral therapy, decay rates in blood CD4+ T cells are faster for intact than for defective proviruses, and intact provirus frequencies are similar in mucosal and circulating T cells.