New research was presented at IAS 2019, the 10th International AIDS Society Conference on HIV Science, from July 21-24 in Mexico City. The features below highlight some of the studies that emerged from the conference.

Network Intervention Identifies Newly HIV-Infected MSM

Research indicates that patients with recent/acute HIV infection have an increased likelihood of disease transmission when compared with those with longer-term infection. To evaluate the effectiveness of identifying recent infections, researchers compared networks of recently and long-term HIV-infected individuals. The networks of each patient type (recent and long-term) were recruited and tested for HIV and syphilis infection, with per-seed yield ratios of recruitment compared between the arms. Overall, 41.6% of participants were identified as HIV-positive. HIV prevalence was higher in networks of recently infected individuals (34.4%) than in long-term infected participants (19.4%). Networks of recently infected participants were also found to have more individuals identified with active syphilis infection (15.6%) when compared with those of long-term infected participants (9.7%). The study authors conclude that allocation “of public health resources may be improved by targeting interventions toward networks of recently HIV-infected individuals.”



Social Network Intervention for PrEP Adoption

With the hypothesis that peer-driven strategies leveraging existing online social networks may be an effective approach to engage young black and Latinx men who have sex with men (YBLMSM) for HIV prevention, study investigators developed and tested the feasibility, acceptability, and preliminary impact of a theory-based, online intervention addressing barriers to pre-exposure prophylaxis (PrEP) adoption in a cluster randomized control trial. The intervention (ePrEP) was a 6-week campaign addressing PrEP barriers, developed and delivered by YBLMSM influential peers (IPs) via private Facebook/Instagram groups to their existing online-social-networks. IPs posted condition-specific content to their respective groups and facilitated discussions about the content. IPs were compared with an attention-matched control group. At 12-weeks, more than 90% of participants were retained in both arms, 82% reported they would continue participating, 78% reported high satisfaction, and 75% stated they would recommend friends to participate. At 12-weeks, ePrEP participants showed greater increases in knowledge, communication skills about PrEP use, and decreases in PrEP stigma when compared with controls.



Point-of-Care Urine Assay Measures PrEP & ART Adherence

Previous studies indicate that high levels of adherence to HIV prevention and treatment regimens is associated with reduced HIV transmission risk, as well as viral suppression in HIV-positive patients. Additional research suggest that overall adherence in this area is sub-optimal, with available adherence assessments being either inadequate to too expensive for widespread use. Researchers who developed an antibody specific to tenofovir—based on the prodrugs of most antiretroviral (ART) and all pre-exposure prophylaxis PrEP regimens—for use in a lateral flow immunoassay (LFIA) format, used this point-of-care (POC) LFIA to test 160 urine samples for TFV concentrations above or below the 650 ng/mL cutoff and compared their results with those of a liquid chromatography (LC)-mass spectrometry (MS)/MS-based test. When compared with the LC-MS/MS tests, the POC LFIA had 100% sensitivity and 100% specificity. The study team observed no changes during up to 21 days in the performance of LFIA with storage at room temperature, 45°C, and 55°C. They conclude that their “novel POC LFIA can inexpensively facilitate real-time monitoring of adherence to TFV-based PrEP and ART, enabling providers to improve the allocation of adherence interventions to patients.”



Memory, Substance Use & Missed HIV Clinic Visits

Data suggest that memory impairment is common among people living with HIV/AIDS (PLWHA), may impact their daily activities, including HIV clinic visits, and may exacerbate the effect of substance use on HIV clinic visits. To confirm the latter two associations, study investigators recruited HIV-positive patients and collected demographic, self-report substance use, memory, and missed HIV clinic visit data through survey methods. Memory impairment was measured with the abbreviated Cognitive Difficulties Scale (CDS), with scores greater than the median of 5 implying more memory impairment. Among participants, 24% reported a missed HIV clinic visit in the previous 6 months. Younger age, unstable housing or homelessness, and walking or bike riding for transportation were associated with missed visits in bivariate analyses. Past-year drug use (adjusted odds ratio [AOR], 1.68) and CDS score greater than median (AOR, 1.69) were associated with missed visits after controlling for demographics, housing, and transportation. When compared with participants with no drug use and CDS scores of 1-5, those who used drugs and had a CDS score above 5 hand an estimated AOR of 2.89 for missed clinic visits.


Healthcare Coverage & Viral Suppression among MSM

Prior research shows that access and adherence to HIV treatment are key to stopping transmission among HIV-infected men who have sex with men (MSM). Based on the premise that having health insurance can facilitate access to treatment, researchers analyzed the association between reported health coverage and viral suppression among MSM living with HIV using multivariable logistic regression adjusting for age, race, employment, household income, education, and recruitment method into the study. Among participants with available viral load measurements at screening, 79% were black, 87% had health coverage, and 82% were virally suppressed. After covariate adjustment, having health coverage was significantly associated with higher odds of being virally suppressed (odds ratio [OR], 1.67). Participants older than 35 had significantly higher odds of being insured (OR, 3.88), whereas those with household incomes of $20,000 per year or lower had marginally lower odds of being insured (OR, 0.57).