HIV drug resistance in a cohort of HIV-infected MSM in the United States

Performance of the Applied Biosystems HIV-1 Genotyping Kit with Integrase

HIV genotyping is used to assess HIV susceptibility to antiretroviral drugs. The Applied Biosystems HIV-1 Genotyping Kit with Integrase (AB kit, Thermo Fisher Scientific) detects resistance-associated mutations (RAMs) in HIV protease (PR), reverse transcriptase (RT), and integrase (IN). We compared results from the AB kit with results obtained previously with the ViroSeq HIV-1 Genotyping System. DNA amplicons from the AB kit were also analyzed using next-generation sequencing (NGS). HIV RNA was extracted using the MagNA Pure 24 instrument (Roche Diagnostics; 96 plasma samples, HIV subtype B, viral load range: 530-737,741 copies/mL). FASTA files were generated from AB kit data using Exatype (Hyrax Biosciences). DNA amplicons from the AB kit were also analyzed by NGS using the Nextera XT kit (Illumina). Drug resistance was predicted using the Stanford HIV Drug Resistance Database. The mean genetic distance for sequences from ViroSeq and the AB kit was 0.02% for PR/RT and 0.04% for IN; 103 major RAMs were detected by both methods. Four additional major RAMs were detected by the AB kit only. These four major RAMs were also detected by NGS (detected in 18.1%-38.2% of NGS reads). NGS detected 27 major RAMs that were not detected with either of the Sanger sequencing-based kits. All major RAMs detected with ViroSeq were detected with the AB kit; additional RAMs were detected with the AB kit only. DNA amplicons from the AB kit can be used for NGS for more sensitive detection of RAMs.

HTPN 078: an enhanced case management study to achieve viral suppression among viremic HIV-positive men who have sex with men in the United States

OBJECTIVES

After identifying and recruiting men who have sex with men living with HIV and virally unsuppressed, this study attempted to enhance treatment and care via case management to increase the proportion who achieved viral suppression.

DESIGN

Participants were randomized into one of two study arms: standard of care (SOC) or enhanced case management (CM) intervention. Participants were followed for 12 months with quarterly study assessments, with blood collected for CD4+ cell count testing, HIV viral load testing (primary prespecified outcome), and plasma storage.

METHODS

Participants identified via respondent-driven sampling and direct recruitment and were invited to participate in the randomized controlled trial. The CM intervention provided a wide range of support services including, health education, clinical care coordination, medication adherence support, and social service assistance. The month-12 assessment included questions about healthcare utilization, stigma, substance use, and mental health.

RESULTS

Among the 144 participants virally unsuppressed at baseline, most had had a previous positive HIV test result; were Black, non-Hispanic, gay and bisexual men, aged 22-50. Among the 128 participants at the last study visit, 68 were virally suppressed, with no statistically significant difference between the CM and SOC arms (viral suppression 42% and 53%, respectively; adjusted odds ratio = 0.62 [P = 0.15; 95% confidence interval: 0.32, 1.2]).

CONCLUSIONS

Reaching targets of at least 90% sustained viral suppression among all people with HIV will likely require more than an individual-level CM approach that addresses barriers to optimal care and treatment at multiple levels.

The Effect of Treatment-Associated Mutations on HIV Replication and Transmission Cycles

HIV/AIDS mortality has been decreasing over the last decade. While promising, this decrease correlated directly with increased use of antiretroviral drugs. As a natural consequence of its high mutation rate, treatments provide selection pressure that promotes the natural selection of escape mutants. Individuals may acquire drug-naive strains, or those that have already mutated due to treatment. Even within a host, mutation affects HIV tropism, where initial infection begins with R5-tropic virus, but the clinical transition to AIDS correlates with mutations that lead to an X4-tropic switch. Furthermore, the high mutation rate of HIV has spelled failure for all attempts at an effective vaccine. Pre-exposure drugs are currently the most effective drug-based preventatives, but their effectiveness is also threatened by viral mutation. From attachment and entry to assembly and release, the steps in the replication cycle are also discussed to describe the drug mechanisms and mutations that arise due to those drugs. Revealing the patterns of HIV-1 mutations, their effects, and the coordinated attempt to understand and control them will lead to effective use of current preventative measures and treatment options, as well as the development of new ones.

Optimized phylogenetic clustering of HIV-1 sequence data for public health applications

Clusters of genetically similar infections suggest rapid transmission and may indicate priorities for public health action or reveal underlying epidemiological processes. However, clusters often require user-defined thresholds and are sensitive to non-epidemiological factors, such as non-random sampling. Consequently the ideal threshold for public health applications varies substantially across settings. Here, we show a method which selects optimal thresholds for phylogenetic (subset tree) clustering based on population. We evaluated this method on HIV-1 pol datasets (n = 14, 221 sequences) from four sites in USA (Tennessee, Washington), Canada (Northern Alberta) and China (Beijing). Clusters were defined by tips descending from an ancestral node (with a minimum bootstrap support of 95%) through a series of branches, each with a length below a given threshold. Next, we used pplacer to graft new cases to the fixed tree by maximum likelihood. We evaluated the effect of varying branch-length thresholds on cluster growth as a count outcome by fitting two Poisson regression models: a null model that predicts growth from cluster size, and an alternative model that includes mean collection date as an additional covariate. The alternative model was favoured by AIC across most thresholds, with optimal (greatest difference in AIC) thresholds ranging 0.007-0.013 across sites. The range of optimal thresholds was more variable when re-sampling 80% of the data by location (IQR 0.008 - 0.016, n = 100 replicates). Our results use prospective phylogenetic cluster growth and suggest that there is more variation in effective thresholds for public health than those typically used in clustering studies.

A public health approach to monitoring HIV with resistance to HIV pre-exposure prophylaxis

Background

The risk of HIV pre-exposure prophylaxis (PrEP) failure with sufficient medication adherence is extremely low but has occurred due to transmission of a viral strain with mutations conferring resistance to PrEP components tenofovir (TDF) and emtricitabine (FTC). The extent to which such strains are circulating in the population is unknown.

Methods

We used HIV surveillance data to describe primary and overall TDF/FTC resistance and concurrent viremia among people living with HIV (PLWH). HIV genotypes conducted for clinical purposes are reported as part of HIV surveillance. We examined the prevalence of HIV strains with mutations conferring intermediate to high level resistance to TDF/FTC, defining primary resistance (predominantly K65R and M184I/V mutations) among sequences reported within 3 months of HIV diagnosis and total resistance for sequences reported at any time. We examined trends in primary resistance during 2010–2019 and total resistance among all PLWH in 2019. We also monitored resistance with viremia (≥1,000 copies/mL) at the end of 2019 among PLWH.

Results

Between 2010 and 2019, 2,172 King County residents were diagnosed with HIV; 1,557 (72%) had a genotypic resistance test within three months; three (0.2%) had primary TDF/FTC resistance with both K65R and M184I/V mutations. Adding isolated resistance for each drug resulted in 0.3% with primary TDF resistance and 0.8% with primary FTC resistance. Of 7,056 PLWH in 2019, 4,032 (57%) had genotype results, 241 (6%) had TDF/FTC resistance and 15 (0.4% of those with a genotype result) had viremia and TDF/FTC resistance.

Conclusions

Primary resistance and viremia combined with TDF/FTC resistance are uncommon in King County. Monitoring trends in TDF/FTC resistance coupled with interventions to help ensure PLWH achieve and maintain viral suppression may help ensure that PrEP failure remains rare.

Early versus delayed antiretroviral therapy based on genotypic resistance test: Results from a large retrospective cohort study

Rapid start of antiretroviral therapy (ART) pending genotypic resistance test (GRT) has been recently proposed, but the effectiveness of this strategy is still debated. The rate of virological success (VS), defined as HIV‐RNA < 50 copies/ml, with and without GRT was compared in drug‐naïve individuals enrolled in the Italian ARCA cohort who started ART between 2015 and 2018. 521 individuals started ART: 397 without GRT (pre‐GRT group) and 124 following GRT (post‐GRT group). Overall, 398 (76%) were males and 30 (6%) were diagnosed with AIDS. In the pre‐GRT group, baseline CD4+ cell counts were lower (p < 0.001), and viral load was higher (p < 0.001) than in the post‐GRT group. The estimated probability of VS in pre‐GRT versus post‐GRT group was 72.54% (CI₉₅: 67.78–76.60) versus 66.94% (CI₉₅: 57.53–74.26) at Week 24 and 92.40% (CI₉₅: 89.26–94.62) versus 92.92% (CI₉₅: 86.35–96.33) at Week 48, respectively (p = 0.434). At Week 48, VS was less frequent among individuals with baseline CD4+ cell counts <200 versus >500 (90.33% vs. 97.33%), log viral load <5.00 versus >5.70 log₁₀ cps/ml (97.17% vs 78.16%; p < 0.001), and those treated with protease inhibitors or non‐nucleoside reverse transcriptase inhibitors versus those treated with integrase strand transfer inhibitors (p < 0.001). The rate of VS does not seem to be affected by an early ART initiation pending GRT results, but it could be influenced by the composition of the ART regimen, as well as immuno‐virological parameters.

Use of HIV Recency Assays for HIV Incidence Estimation and Other Surveillance Use Cases: Systematic Review

BACKGROUND

HIV assays designed to detect recent infection, also known as "recency assays," are often used to estimate HIV incidence in a specific country, region, or subpopulation, alone or as part of recent infection testing algorithms (RITAs). Recently, many countries and organizations have become interested in using recency assays within case surveillance systems and routine HIV testing services to measure other indicators beyond incidence, generally referred to as "non-incidence surveillance use cases."

OBJECTIVE

This review aims to identify published evidence that can be used to validate methodological approaches to recency-based incidence estimation and non-incidence use cases. The evidence identified through this review will be used in the forthcoming technical guidance by the World Health Organization (WHO) and United Nations Programme on HIV/AIDS (UNAIDS) on the use of HIV recency assays for identification of epidemic trends, whether for HIV incidence estimation or non-incidence indicators of recency.

METHODS

To identify the best methodological and field implementation practices for the use of recency assays to estimate HIV incidence and trends in recent infections for specific populations or geographic areas, we conducted a systematic review of the literature to (1) understand the use of recency testing for surveillance in programmatic and laboratory settings, (2) review methodologies for implementing recency testing for both incidence estimation and non-incidence use cases, and (3) assess the field performance characteristics of commercially available recency assays.

RESULTS

Among the 167 documents included in the final review, 91 (54.5%) focused on assay or algorithm performance or methodological descriptions, with high-quality evidence of accurate age- and sex-disaggregated HIV incidence estimation at national or regional levels in general population settings, but not at finer geographic levels for prevention prioritization. The remaining 76 (45.5%) described the field use of incidence assays including field-derived incidence (n=45), non-incidence (n=25), and both incidence and non-incidence use cases (n=6). The field use of incidence assays included integrating RITAs into routine surveillance and assisting with molecular genetic analyses, but evidence was generally weaker or only reported on what was done, without validation data or findings related to effectiveness of using non-incidence indicators calculated through the use of recency assays as a proxy for HIV incidence.

CONCLUSIONS

HIV recency assays have been widely validated for estimating HIV incidence in age- and sex-specific populations at national and subnational regional levels; however, there is a lack of evidence validating the accuracy and effectiveness of using recency assays to identify epidemic trends in non-incidence surveillance use cases. More research is needed to validate the use of recency assays within HIV testing services, to ensure findings can be accurately interpreted to guide prioritization of public health programming.

Statewide Longitudinal Trends in Transmitted HIV-1 Drug Resistance in Rhode Island, USA

Background

HIV-1 transmitted drug resistance (TDR) remains a global challenge that can impact care, yet its comprehensive assessment is limited and heterogenous. We longitudinally characterized statewide TDR in Rhode Island.

Methods

Demographic and clinical data from treatment-naïve individuals were linked to protease, reverse transcriptase, and integrase sequences routinely obtained over 2004-2020. TDR extent, trends, impact on first-line regimens, and association with transmission networks were assessed using the Stanford Database, Mann-Kendall statistic, and phylogenetic tools.

Results

In 1123 individuals, TDR to any antiretroviral increased from 8% (2004) to 26% (2020), driven by non-nucleotide reverse transcriptase inhibitor (NNRTI; 5%-18%) and, to a lesser extent, nucleotide reverse transcriptase inhibitor (NRTI; 2%-8%) TDR. Dual- and triple-class TDR rates were low, and major integrase strand transfer inhibitor resistance was absent. Predicted intermediate to high resistance was in 77% of those with TDR, with differential suppression patterns. Among all individuals, 34% were in molecular clusters, some only with members with TDR who shared mutations. Among clustered individuals, people with TDR were more likely in small clusters.

Conclusions

In a unique (statewide) assessment over 2004-2020, TDR increased; this was primarily, but not solely, driven by NNRTIs, impacting antiretroviral regimens. Limited TDR to multiclass regimens and pre-exposure prophylaxis are encouraging; however, surveillance and its integration with molecular epidemiology should continue in order to potentially improve care and prevention interventions.

HIV Prevention Trials Network 078: High Prevalence of Hepatitis C Virus Antibodies Among Urban US Men Who Have Sex With Men, Independent of Human Immunodeficiency Virus Status

BACKGROUND

Sexual transmission of hepatitis C virus (HCV) is uncommon, yet documented among men who have sex with men (MSM), primarily among those with human immunodeficiency virus (HIV).

METHODS

In the HIV Prevention Trials Network 078 study (HPTN 078), which assessed an integrated strategy to achieve HIV viral suppression, 1305 MSM were screened across 4 geographically diverse US cities. At screening, demographic/behavioral/psychosocial questionnaires were completed, along with HIV and HCV testing. Multivariable logistic regression was used to evaluate associations with HCV antibody positivity.

RESULTS

Among the 1287 (99%) of the MSM with HCV antibody results, the median age was 41, 69% were black, 85% had a high school education or more, 35% were employed, 70% had HIV, and 21% had undergone substance use counseling. The median lifetime number of male sexual partners was 17 (interquartile range, 6-50), and 246 (19%) were HCV antibody positive. HCV antibody positivity was high in MSM with HIV (20%) and MSM without HIV (17%) (P = .12) and was higher in those receiving substance use counseling (36%) than in those who had not (15%) (P ≤ .01). Substance use counseling (odds ratio, 2.51; 95% confidence interval, 1.80-3.51) and unstable housing (2.16; 1.40-3.33) were associated with HCV antibody positivity.

CONCLUSIONS

Nearly 1 in 5 MSM screened for HPTN 078 have been infected with HCV. The prevalence is high regardless of HIV status and is high even in those who did not undergo substance use counseling. In HIV burden networks, high HCV infection prevalence may occur in MSM without HIV. As implementation of preexposure prophylaxis expands and condom use declines, routine HCV counseling and screening among MSM are important.

Transmitted drug resistance to Tenofovir/Emtricitabine among persons with newly diagnosed HIV infection in Shenyang city, Northeast China from 2016 to 2018

BACKGROUND

To assess transmitted drug resistance (TDR) to tenofovir (TDF)/emtricitabine (FTC), using as pre-exposure prophylaxis, among newly diagnosed human immunodeficiency virus-1 (HIV-1)-infected residents in Shenyang city, northeast China.

METHODS

Demographic and epidemiological information of all newly diagnosed HIV-1 infected residents in Shenyang city from 2016 to 2018 were anonymously collected from the local HIV epidemic database. HIV-1 pol sequences were amplified from RNA in cryopreserved plasma samples and sequenced directly. Viral subtypes were inferred with phylogenetic analysis and drug resistance mutations (DRMs) were determined according to the Stanford HIVdb algorithm. Recent HIV infection was determined with HIV Limiting Antigen avidity electro immunoassay.

RESULTS

A total of 2176 sequences (92.4%, 2176/2354) were obtained; 70.9% (1536/2167) were CRF01_AE, followed by CRF07_BC (18.0%, 391/2167), subtype B (4.7%, 102/2167), other subtypes (2.6%, 56/2167), and unique recombinant forms (3.8%, 82/2167). The prevalence of TDR was 4.9% (107/2167), among which, only 0.6% (13/2167) was resistance to TDF/FTC. Most of these subjects had CRF01_AE strains (76.9%, 10/13), were unmarried (76.9%, 10/13), infected through homosexual contact (92.3%, 12/13), and over 30 years old (median age: 33). The TDF/FTC DRMs included K65R (8/13), M184I/V (5/13), and Y115F (2/13). Recent HIV infection accounted for only 23.1% (3/13). Most cases were sporadic in the phylogenetic tree, except two CRF01_AE sequences with K65R (Bootstrap value: 99%).

CONCLUSIONS

The prevalence of TDR to TDF/FTC is low among newly diagnosed HIV-infected cases in Shenyang, suggesting that TDR may have little impact on the protective effect of the ongoing CROPrEP project in Shenyang city.

Performance of a high-throughput next-generation sequencing method for analysis of HIV drug resistance and viral load

OBJECTIVES

To evaluate the performance of a high-throughput research assay for HIV drug resistance testing based on whole genome next-generation sequencing (NGS) that also quantifies HIV viral load.

METHODS

Plasma samples (n = 145) were obtained from HIV-positive MSM (HPTN 078). Samples were analysed using clinical assays (the ViroSeq HIV-1 Genotyping System and the Abbott RealTime HIV-1 Viral Load assay) and a research assay based on whole-genome NGS (veSEQ-HIV).

RESULTS

HIV protease and reverse transcriptase sequences (n = 142) and integrase sequences (n = 138) were obtained using ViroSeq. Sequences from all three regions were obtained for 100 (70.4%) of the 142 samples using veSEQ-HIV; results were obtained more frequently for samples with higher viral loads (93.5% for 93 samples with >5000 copies/mL; 50.0% for 26 samples with 1000-5000 copies/mL; 0% for 23 samples with <1000 copies/mL). For samples with results from both methods, drug resistance mutations (DRMs) were detected in 33 samples using ViroSeq and 42 samples using veSEQ-HIV (detection threshold: 5.0%). Overall, 146 major DRMs were detected; 107 were detected by both methods, 37 were detected by veSEQ-HIV only (frequency range: 5.0%-30.6%) and two were detected by ViroSeq only. HIV viral loads estimated by veSEQ-HIV strongly correlated with results from the Abbott RealTime Viral Load assay (R2 = 0.85; n = 142).

CONCLUSIONS

The NGS-based veSEQ-HIV method provided results for most samples with higher viral loads, was accurate for detecting major DRMs, and detected mutations at lower levels compared with a method based on population sequencing. The veSEQ-HIV method also provided HIV viral load data.

An evaluation of assumptions underlying respondent-driven sampling and the social contexts of sexual and gender minority youth participating in HIV clinical trials in the United States

INTRODUCTION

Respondent-driven sampling (RDS) has been an effective sampling strategy for HIV research in many settings, but has had limited success among some youth in the United States. We evaluated a modified RDS approach for sampling Black and Latinx sexual and gender minority youth (BLSGMY) and explored how lived experiences and social contexts of BLSGMY youth may impact traditional RDS assumptions.

METHODS

RDS was implemented in three US cities, Baltimore, Philadelphia and Washington DC, to engage BLSGMY aged 15 to 24 years in HIV prevention or care intervention trials. RDS was modified to include targeted seed recruitment from venues, Internet and health clinics, and provided options for electronic or paper coupons. Qualitative interviews were conducted among a sub-sample of RDS participants to explore their experiences with RDS. Interviews were coded using RDS assumptions as an analytic framework.

RESULTS

Between August 2017 and October 2019, 405 participants were enrolled, 1670 coupons were distributed, with 133 returned, yielding a 0.079 return rate. The maximum recruitment depth was four waves among seeds that propagated. Self-reported median network size was 5 (IQR 2 to 10) and reduced to 3 (IQR 1 to 5) when asked how many peers were seen in the past 30 days. Qualitative interviews (n = 27) revealed that small social networks, peer trust and targeted referral of peers with certain characteristics challenged network, random recruitment, and reciprocity assumptions of RDS. HIV stigma and research hesitancy were barriers to participation and peer referral. Other situational factors, such as phone ownership and access to reliable transportation, reportedly created challenges for referred peers to participate in research.

CONCLUSIONS

Small social networks and varying relationships with peers among BLSGMY challenge assumptions that underlie traditional RDS. Modified RDS approaches, including those that incorporate social media, may support recruitment for community-based research but may challenge assumptions of reciprocal relationships. Research hesitancy and situational barriers are relevant and must be addressed across any sampling method and study design that includes BLSGMY in the United States.

Primary HIV-1 infection in users of pre-exposure prophylaxis

Pre-exposure prophylaxis (PrEP) has proven to be a highly effective and safe way to prevent HIV infection. Seroconversion and primary HIV infection are exceptional if adherence to PrEP is good. However, primary HIV infection while using PrEP can occur, albeit rarely, and HIV drug resistance might develop. Furthermore, the scope of PrEP is expected to expand, and clinicians might face potential seroconversions and primary HIV infection in patients starting or taking PrEP. The characteristics of primary HIV infection in users of PrEP are poorly described. PrEP users present a lower viral load peak during primary HIV infection and, frequently, fewer symptoms than individuals not exposed to PrEP. Additionally, PrEP prolongs the stages of seroconversion, thus potentially complicating diagnosis of primary HIV infection. Drug resistance is rare, occurring mostly when PrEP is initiated in undiagnosed patients who are at an extremely early stage of infection, in whom detection of HIV-RNA was not used to rule out HIV infection. Therefore, careful exclusion of primary HIV infection before starting PrEP is crucial. In patients presenting with primary HIV infection while on PrEP, a drug with a high genetic barrier (or even two) should be added to tenofovir disoproxil fumarate-emtricitabine until test results for resistance are available.

High Prevalence of HIV-1 Drug Resistance and Dynamics of Transmission Among High-Risk Populations in Port-au-Prince, Haiti

BACKGROUND

In low HIV prevalence settings, understanding the transmission dynamics and the impact of drug resistance is critical to curb down the epidemic. This study aims to explore the prevalence and dynamics of transmission of HIV drug-resistance mutations (DRMs) among key populations in Haiti.

SETTINGS

Eligible participants (naive, treated) were selected from 7 key population friendly health care centers in Port-au-Prince, Haiti, from September 2018 to July 2019.

METHODS

A total of 119 HIV-1 pol sequences were analyzed from men having sex with men (MSM), female sex workers (FSWs), and their sexual partners. Screening for HIV DRMs was performed using the Stanford University Drug Resistance Database. Phylogenetic and network analyses using HIV-TRACE software were performed to infer putative relationships and shared DRMs.

RESULTS

Of the 119 participants, 62.2% were men (74/119), and 75.7% of them (56/74) reported MSM as a main risk factor. The overall DRM prevalence was 58.8% (70/119). A DRM was observed in 37.5% of MSM (21/56), 82.2% of FSWs (37/45), and 66.7% (12/18) among FSWs' clients. In a multivariate model, age and FSWs were significant predictors for DRMs (P = 0.001). Transmission network analysis found 24 of the 119 (20.2%) genetically linked individuals forming 8 clusters. Clustering participants were mostly MSM (15/24; 62.5%). Five clusters (62.5%) had shared DRMs, and K103N and M184V were the main shared mutations.

CONCLUSIONS

High prevalence of HIV DRMs was observed among MSM, FSWs, and their clients in Port-au-Prince, Haiti. Network analysis revealed frequent DRM transmission among genetically linked individuals, highlighting the need for appropriate interventions to limit HIV transmission in these high-risk populations.

An evaluation of assumptions underlying respondent-driven sampling and the social contexts of sexual and gender minority youth participating in HIV clinical trials in the United States

Introduction:

Respondent-driven sampling has been an effective sampling strategy for HIV research in many settings, but has had limited success among some youth in the United States. We evaluated a modified RDS approach for sampling Black and Latinx sexual and gender minority youth (BLSGMY) and evaluates how lived experiences and social contexts of BLSGMY youth may impact traditional RDS assumptions.

Methods:

RDS was implemented in three cities to engage BLSGMY in HIV prevention or care intervention trials. RDS was modified to include targeted seed recruitment from venues, internet, and health clinics, and provided options for electronic or paper coupons. Qualitative interviews were conducted among a sub-sample of RDS participants to explore their experiences with RDS. Interviews were coded using RDS assumptions as an analytic framework.

Results:

Between August 2017 and October 2019, 405 participants were enrolled, 1,670 coupons were distributed, with 133 returned, yielding a 0.079 return rate. The maximum recruitment depth was 4 waves among seeds that propagated. Self-reported median network size was 5 (IQR 2–10) and reduced to 3 (IQR 1–5) when asked how many peers were seen in the past 30 days. Qualitative interviews (n=27) revealed that small social networks, peer trust, and targeted referral of peers with certain characteristics challenged network, random recruitment, and reciprocity assumptions of RDS. HIV stigma and research hesitancy were barriers to participation and peer referral.

Conclusions:

Small social networks and varying relationships with peers among BLSGMY challenge assumptions that underlie traditional RDS. Modified RDS approaches, including those that incorporate social media, may support recruitment for community-based research but may challenge assumptions of reciprocal relationships. Research hesitancy and situational barriers must be addressed in recruitment and study designs.