PrEP as a feature in the optimal landscape of combination HIV prevention in sub-Saharan Africa

Associations with HIV preexposure prophylaxis use by cisgender female sex workers in two Ugandan cities

BACKGROUND

Sex workers of all genders have a high risk of HIV acquisition and are a priority population for HIV pre-exposure prophylaxis (PrEP). We aimed to assess current oral PrEP use and associated factors among cisgender female sex workers (FSW) in two Ugandan cities.

METHODS

We administered a survey questionnaire to 236 HIV-negative FSW in the cities of Mbale and Mbarara from January to March 2020. The survey was nested in a quasi-experimental study to assess the effect of peer education and text message reminders on the uptake of regular sexually transmitted infection (STI) and HIV testing. Using interviewer-administered questionnaires, we obtained data on current self-reported tenofovir-based oral PrEP use. We used modified Poisson regression with robust standard errors to evaluate the factors associated with current oral PrEP usage.

RESULTS

Nearly 70% of FSWs reported taking an HIV test during the past three months. Among the respondents, 33% (33/100) in Mbale and 67% (91/136) in Mbarara reported having ever heard of PrEP. However, only 9.7% (23/236) self-reported currently taking oral-PrEP. In Mbarara, FSWs were twice as likely to be aware of or use oral PrEP than those in Mbale (adjusted prevalence ratio [aPR] 2.33; 95% confidence interval (CI) 1.19-3.97; p = 0.01). Additionally, current use was positively associated with attainment of secondary (aPR 2.50; 95% CI: 1.14-5.45; p = 0.02) or tertiary education (aPR 3.12; 95% CI: 1.09-8.96; p = 0.03).

CONCLUSION

PrEP use in this cohort of FSWs was low and was associated with location and level of education. To increase PrEP uptake among FSWs, targeted educational campaigns and implementation studies are needed, particularly for those with lower levels of education.

Factors Associated with Usage of Oral-PrEP among Female Sex Workers in Nairobi, Kenya, Assessed by Self-Report and a Point-of-Care Urine Tenofovir Immunoassay

Pre-exposure prophylaxis (PrEP) is highly effective at reducing HIV acquisition. We aimed to estimate usage of oral-PrEP, and factors associated with adherence among female sex workers (FSWs) in Nairobi, Kenya, using a novel point-of-care urine tenofovir lateral flow assay (LFA). The Maisha Fiti study randomly selected FSWs from Sex Worker Outreach Program clinics in Nairobi. Data were collected from 1003 FSWs from June-October 2019, including surveys on self-reported oral-PrEP adherence. Adherence was also measured using the LFA for HIV-negative FSWs currently taking oral-PrEP. Informed by a social-ecological theoretical framework, we used hierarchical multivariable logistic regression models to estimate associations between individual, interpersonal/community, and structural/institutional-level factors and either self-reported or LFA-assessed adherence. Overall, 746 HIV-negative FSWs aged 18-40 participated in the study, of whom 180 (24.1%) self-reported currently taking oral-PrEP. Of these, 56 (31.1%) were adherent to oral-PrEP as measured by LFA. In the multivariable analyses, associations with currently taking oral-PrEP included having completed secondary education, high alcohol/substance use, feeling empowered to use PrEP, current intimate partner, no recent intimate partner violence, having support from sex worker organisations, experiencing sex work-related stigma, and seeking healthcare services despite stigma. Associations with oral-PrEP LFA-measured adherence measured included having only primary education, experience of childhood emotional violence, belonging to a higher wealth tertile, and being nulliparous. Oral-PrEP adherence, measured by self-report or objectively, is low among FSWs in Nairobi. Programs to improve oral-PrEP usage among FSWs should work to mitigate social and structural barriers and involve collaboration between FSWs, healthcare providers and policymakers.

The Feasibility and Acceptability of Using Mobile Applications for HIV Testing, Prevention, and Treatment Among Adolescent Girls and Young Women in Cameroon: A Cross-Sectional Study

ABSTRACT

Adolescent girls and young women (AGYW) are vulnerable populations to HIV/AIDS. We conducted a cross-sectional survey among 637 AGYW in Cameroon to study the feasibility and willingness to use mobile applications (apps) for HIV testing, prevention, and treatment. We found that phone ownership is high among AGYW, where 93.9% ( n = 598) of them (median age: 22 years, interquartile range: 21-24 years) had access to a smartphone, 49.5% ( n = 315) frequently searched for health information, and 48.9% ( n = 312) frequently used health-related apps. AGYW's willingness to use mobile apps for HIV testing, prevention, and treatment were 87.9% ( n = 560), 84.4% ( n = 538), and 84.9% ( n = 541), respectively. The high willingness to use apps was associated with older age, HIV testing, and searching for health information on a phone. Barriers to willingness included having no internet access, concerns about internet cost and privacy, and lack of consistent access to a smartphone.

HIV Pre-Exposure Prophylaxis Uptake Among High-Risk Population in Sub-Saharan Africa: A Systematic Review and Meta-Analysis

Globally, 38.4 million people are affected by the human immunodeficiency virus (HIV) pandemic, and more than 2.5 million new HIV infections occur yearly. HIV pre-exposure prophylaxis (PrEP) has been widely recognized as a potential way to prevent new infections among risk population. There is a paucity of abridged evidence on the level and barriers to PrEP service uptake in sub-Saharan Africa (SSA). Therefore, we conducted a systematic review to synthesize existing evidence on PrEP uptake in SSA. Relevant studies were searched from major databases (PubMed and PsychInfo) and direct Google Scholar. Data were extracted and recorded using a pilot-tested template. Methodological rigor, heterogeneity and publication bias of studies were assessed to minimize the inclusion of erroneous findings. A random effect model was used for the meta-analysis followed by narrative metasynthesis. The protocol of this systematic review has been by registered PROSPERO (ID: CRD42022308855). A total of 1830 studies were retrieved, and 30 studies met inclusion criteria of the systematic review. People who heard about PrEP ranged from 23% to 98%. The pooled prevalence of willingness to use PrEP was 64.2% (95% confidence interval: 55.5-72.0). Fear of side effect, stigma, nonreceptive attitude, cost of pills, low awareness about PrEP, perceived reason about the effectiveness of PrEP, and lack of friendly services were the common barriers to PrEP uptake in Africa. In conclusion, comprehensive knowledge and willingness to use PrEP were low in SSA. The barriers to low PrEP service uptake are avoidable through comprehensive awareness creation and availing essential services to key population in Africa. Expanding educational messages to key population using friendly approaches and more accessible platforms, engaging stakeholders, and integrating PrEP service with routine health care are important to foster HIV prevention and control in the future.

HIV Pre-exposure Prophylaxis Uptake and Continuation Among Key Populations in Cameroon: Lessons Learned From the CHAMP Program

INTRODUCTION

Pre-exposure prophylaxis (PrEP) is proven to be a highly effective HIV prevention method for key populations. However, its scale-up in resource-limited settings remains suboptimal. This paper seeks to describe PrEP initiation and continuation among key populations in Cameroon.

METHODOLOGY

From June 2019 through October 2020, we collected routine program data on PrEP uptake and continuation among female sex workers (FSWs) and men who have sex with men (MSM) in the Continuum of prevention, care and treatment of HIV/AIDS with Most-at-risk Populations (CHAMP) program in Cameroon. PrEP was offered to clients who tested negative for HIV and were assessed to potentially benefit from PrEP. Using survival analysis, we identified factors associated with PrEP discontinuation over time with significance set at 5%.

RESULTS

Overall, 27,750 clients were sensitized for PrEP of whom 3,138 persons were eligible to start PrEP and 1,409 (45%; FSW: 691 and MSM: 718) initiated PrEP. The PrEP continuation rate was 37% at 3 months, 28% at 6 months and 19% at 12 months. PrEP discontinuation was significantly higher among FSW than MSM [adjusted hazard ratio (aHR) 1.5 (95% CI: 1.2 to 1.9)] in Yaounde [aHR 1.5 (95% CI: 1.2 to 1.9)] and Bafoussam/Bertoua [aHR 3.1 (2.2-4.5)] relative to Douala. Discontinuation was lower among those with moderate [aHR 0.3 (0.3-0.4)] or good adherence [aHR 0.4 (0.3-0.6)] compared with poor adherence (all P < 0.001).

CONCLUSION

Differentiated approaches to deliver PrEP, create demand, and provide more intensive support for adherence and continuation may support scale-up of PrEP in Cameroon for equitable and prolonged impact on HIV prevention.

Acceptability of multiple modalities of pre-exposure prophylaxis (PrEP) among female sex workers in Tanzania: a mixed-methods study

OBJECTIVES

Modalities of pre-exposure prophylaxis (PrEP) for HIV prevention offer options to women at high risk including female sex workers (FSW). This study aimed to explore FSW's acceptability and preferences for oral pills, long-acting (LA) injectable and vaginal ring PrEP.

DESIGN

Sequential, explanatory, mixed methods.

SETTING

Iringa, Tanzania.

PARTICIPANTS

FSW aged above 18 were recruited from sex work venues using time-location sampling (n=496); HIV-uninfected (n=293) were included in this analysis. Subsequently, survey participants were recruited for in-depth interviews (n=10) and two focus group discussions (n=20).

PRIMARY OUTCOME MEASURES

(1) Acceptability of PrEP (Do you personally think it would be worth it to you to take ART if it could prevent HIV?: yes/no) and (2) preference for LA injectable versus oral pills (If you personally were going to take ART to prevent HIV infection, would you prefer to take it in the form of a daily pill or an injection once every 3 months? Injection/pill).

RESULTS

Participants were (92%) unaware of PrEP but 58% thought it would be worth it to personally take PrEP. Acceptability of PrEP was significantly associated with higher social cohesion (aOR 2.12; 95% CI 1.29 to 3.50) and STI symptoms in the past 6 months (aOR 2.52; 95% CI 1.38 to 4.62). Most (88%) preferred LA vs oral PrEP. Qualitative findings revealed generally positive reactions to all types of PrEP, and they were viewed as a welcome backup to condoms. Participants had concerns about pills (burden of daily use, stigma from clients), and the vaginal ring (fear of client noticing and becoming suspicious, fear of infertility) and overall preferred LA-PrEP (less frequent use, easy to hide, belief in higher efficacy).

CONCLUSIONS

Offering multiple formulations of PrEP within the context of community-driven HIV prevention interventions among FSW may facilitate increased uptake and adherence. LA injectable PrEP may be a particularly preferred formulation among FSW.

TRIAL REGISTRATION NUMBER

NCT02281578.

Cost-effectiveness of easy-access, risk-informed oral pre-exposure prophylaxis in HIV epidemics in sub-Saharan Africa: a modelling study

BACKGROUND

Approaches that allow easy access to pre-exposure prophylaxis (PrEP), such as over-the-counter provision at pharmacies, could facilitate risk-informed PrEP use and lead to lower HIV incidence, but their cost-effectiveness is unknown. We aimed to evaluate conditions under which risk-informed PrEP use is cost-effective.

METHODS

We applied a mathematical model of HIV transmission to simulate 3000 setting-scenarios reflecting a range of epidemiological characteristics of communities in sub-Saharan Africa. The prevalence of HIV viral load greater than 1000 copies per mL among all adults (HIV positive and negative) varied from 1·1% to 7·4% (90% range). We hypothesised that if PrEP was made easily available without restriction and with education regarding its use, women and men would use PrEP, with sufficient daily adherence, during so-called seasons of risk (ie, periods in which individuals are at risk of acquiring infection). We refer to this as risk-informed PrEP. For each setting-scenario, we considered the situation in mid-2021 and performed a pairwise comparison of the outcomes of two policies: immediate PrEP scale-up and then continuation for 50 years, and no PrEP. We estimated the relationship between epidemic and programme characteristics and cost-effectiveness of PrEP availability to all during seasons of risk. For our base-case analysis, we assumed a 3-monthly PrEP cost of US$29 (drug $11, HIV test $4, and $14 for additional costs necessary to facilitate education and access), a cost-effectiveness threshold of $500 per disability-adjusted life-year (DALY) averted, an annual discount rate of 3%, and a time horizon of 50 years. In sensitivity analyses, we considered a cost-effectiveness threshold of $100 per DALY averted, a discount rate of 7% per annum, the use of PrEP outside of seasons of risk, and reduced uptake of risk-informed PrEP.

FINDINGS

In the context of PrEP scale-up such that 66% (90% range across setting-scenarios 46-81) of HIV-negative people with at least one non-primary condomless sex partner take PrEP in any given period, resulting in 2·6% (0·9-6·0) of all HIV negative adults taking PrEP at any given time, risk-informed PrEP was predicted to reduce HIV incidence by 49% (23-78) over 50 years compared with no PrEP. PrEP was cost-effective in 71% of all setting-scenarios, and cost-effective in 76% of setting-scenarios with prevalence of HIV viral load greater than 1000 copies per mL among all adults higher than 2%. In sensitivity analyses with a $100 per DALY averted cost-effectiveness threshold, a 7% per year discount rate, or with PrEP use that was less well risk-informed than in our base case, PrEP was less likely to be cost-effective, but generally remained cost-effective if the prevalence of HIV viral load greater than 1000 copies per mL among all adults was higher than 3%. In sensitivity analyses based on additional setting-scenarios in which risk-informed PrEP was less extensively used, the HIV incidence reduction was smaller, but the cost-effectiveness of risk-informed PrEP was undiminished.

INTERPRETATION

Under the assumption that making PrEP easily accessible for all adults in sub-Saharan Africa in the context of community education leads to risk-informed use, PrEP is likely to be cost-effective in settings with prevalence of HIV viral load greater than 1000 copies per mL among all adults higher than 2%, suggesting the need for implementation of such approaches, with ongoing evaluation.

FUNDING

US Agency for International Development, US President's Emergency Plan for AIDS Relief, and Bill & Melinda Gates Foundation.

Derivation of an HIV Risk Score for African Women Who Engage in Sex Work

No tool exists to stratify HIV risk in contemporary African female sex worker (FSW) populations. Data from a cohort of HIV-negative FSWs in Mombasa, Kenya from 2010 to 2017 were used to conduct a survival analysis assessing predictors of HIV infection. Stepwise regression was used to construct a multivariable model that formed the basis for the score. Seventeen HIV infections occurred over 1247 person-years of follow-up contributed by 670 women. Using depot medroxyprogesterone acetate (DMPA), having a curable sexually transmitted infection (STI), and being married contributed points to the score. HIV incidence was 0.85/100 person-years in a lower-risk group and 3.10/100 person-years in a higher-risk group. In a cohort with overall HIV incidence < 1.50/100 person-years, this risk score identified a subgroup of FSWs with HIV incidence > 3.00/100 person-years, which is the threshold used by the World Health Organization for initiating pre-exposure prophylaxis (PrEP). If validated in an external population, this tool could be useful for targeted PrEP promotion among higher-risk FSWs.

Potential Impact and Cost-Effectiveness of Condomless-Sex-Concentrated PrEP in KwaZulu-Natal Accounting for Drug Resistance

INTRODUCTION

Oral preexposure prophylaxis (PrEP) in the form of tenofovir-disoproxil-fumarate/emtricitabine is being implemented in selected sites in South Africa. Addressing outstanding questions on PrEP cost-effectiveness can inform further implementation.

METHODS

We calibrated an individual-based model to KwaZulu-Natal to predict the impact and cost-effectiveness of PrEP, with use concentrated in periods of condomless sex, accounting for effects on drug resistance. We consider (1) PrEP availability for adolescent girls and young women aged 15-24 years and female sex workers, and (2) availability for everyone aged 15-64 years. Our primary analysis represents a level of PrEP use hypothesized to be attainable by future PrEP programs.

RESULTS

In the context of PrEP use in adults aged 15-64 years, there was a predicted 33% reduction in incidence and 36% reduction in women aged 15-24 years. PrEP was cost-effective, including in a range of sensitivity analyses, although with substantially reduced (cost) effectiveness under a policy of ART initiation with efavirenz- rather than dolutegravir-based regimens due to PrEP undermining ART effectiveness by increasing HIV drug resistance.

CONCLUSIONS

PrEP use concentrated during time periods of condomless sex has the potential to substantively impact HIV incidence and be cost-effective.

Estimating HIV pre-exposure prophylaxis need and impact in Malawi, Mozambique and Zambia: A geospatial and risk-based analysis

BACKGROUND

Pre-exposure prophylaxis (PrEP), a WHO-recommended HIV prevention method for people at high risk for acquiring HIV, is being increasingly implemented in many countries. Setting programmatic targets, particularly in generalised epidemics, could incorporate estimates of the size of the population likely to be eligible for PrEP using incidence-based thresholds. We estimated the proportion of men and women who would be eligible for PrEP and the number of HIV infections that could be averted in Malawi, Mozambique, and Zambia using prioritisation based on age, sex, geography, and markers of risk.

METHODS AND FINDINGS

We analysed the latest nationally representative Demographic and Health Surveys (DHS) of Malawi, Mozambique, and Zambia to determine the proportion of adults who report behavioural markers of risk for HIV infection. We used prevalence ratios (PRs) to quantify the association of these factors with HIV status. Using a multiplier method, we combined these proportions with the number of new HIV infections by district, derived from district-level modelled HIV estimates. Based on these numbers, different scenarios were analysed for the minimum number of person-years on PrEP needed to prevent 1 HIV infection (NNP). An estimated total of 38,000, 108,000, and 46,000 new infections occurred in Malawi, Mozambique, and Zambia in 2016, corresponding with incidence rates of 0.43, 0.63, and 0.57 per 100 person-years. In these countries, 9%-20% of new infections occurred among people with a sexually transmitted infection (STI) in the past 12 months and 40%-42% among people with either an STI or a non-regular sexual partner (NP) in the past 12 months (STINP). The models estimate that around 50% of new infections occurred in districts with incidence rates ≥1.0% in Mozambique and Zambia and ≥0.5% in Malawi. In Malawi, Mozambique, and Zambia, 35.1%, 21.9%, and 12.5% of the population live in these high-incidence districts. In the most parsimonious scenario, if women aged 15-34 years and men 20-34 years with an STI in the past 12 months living in high-incidence districts were to take PrEP, it would take a minimum of 65.8 person-years on PrEP to avert 1 HIV infection per year in Malawi, 35.2 in Mozambique, and 16.4 in Zambia. Our findings suggest that 3,300, 5,200, and 1,700 new infections could be averted per year in the 3 countries, respectively. Limitations of our study are that these values are based on modelled estimates of HIV incidence and self-reported behavioural risk factors from national surveys.

CONCLUSIONS

A large proportion of new HIV infections in these 3 African countries were estimated to occur among people who had either an STI or an NP in the past year, providing a straightforward means to set PrEP targets. Greater prioritisation of PrEP by district, sex, age, and behavioural risk factors resulted in lower NNPs thereby increasing PrEP cost-effectiveness, but also diminished the overall impact on reducing new infections.

Acceptability of pre-exposure prophylaxis for HIV prevention: facilitators, barriers and impact on sexual risk behaviors among men who have sex with men in Benin

BACKGROUND

In Benin, men who have sex with men (MSM) do not always use condoms during anal sex. Pre-exposure prophylaxis (PrEP) using Truvada® (tenofovir disoproxil fumarate / emtricitabine) may be a complementary HIV prevention measure for MSM. This study aimed at identifying the potential facilitators and barriers to the use of PrEP.

METHODS

This was a cross-sectional study conducted in 2018 among male-born MSM aged 18 years or older who reported being HIV-negative or unaware of their HIV status. The participants were recruited by the RDS technique (respondent driven sampling) in six cities of Benin. Logistic regression analyses, adapted to RDS statistical requirements, were performed to identify the factors associated with PrEP acceptability.

RESULTS

Mean age of the 400 MSM recruited was 26.2 ± 5.0 years. PrEP was known by 50.7% of respondents. The intention to use PrEP was expressed by 90% of MSM. If PrEP effectiveness were 90% or more, 87.8% of the respondents thought they would decrease condom use. In multivariate analysis, the facilitators associated with PrEP acceptability were: not having to pay for PrEP (odds ratio (OR) = 2.39, 95% CI: 1.50-4.46) and its accessibility within MSM networks (OR = 9.82, 95% CI: 3.50-27.52). Only one barrier was significant: the concern that taking PrEP be perceived as marker of adopting HIV risky behaviors (OR = 0.11, 95% CI: 0.04-0.30).

CONCLUSION

In Benin, not all MSM know about PrEP. But once well informed, the majority seems willing to use it if made available. The free availability of the drug and its accessibility in the MSM networks are important facilitators. The possibility of decrease in condom use should not be a barrier to the prescription of PrEP if made available.

The impact of self-selection based on HIV risk on the cost-effectiveness of preexposure prophylaxis in South Africa

OBJECTIVES

We explored the impact and cost-effectiveness of preexposure prophylaxis (PrEP) provision to different populations in South Africa, with and without effective self-selection by individuals at highest risk of contracting HIV (through concurrent partnerships and/or commercial sex).

DESIGN AND METHODS

We used a previously developed HIV transmission model to analyse the epidemiological impact of PrEP provision to adolescents, young adults, pregnant women, female sex workers (FSWs) and (MSM), and data from South African PrEP programmes to estimate the cost and cost-effectiveness of PrEP (cost in 2019 USD per HIV infection averted over 20 years, 2019, 38). PrEP uptake followed data from early implementation sites, scaled-up linearly over 3 years, with target coverage set to 18% for adolescents, young adults and pregnant women, 30% for FSW and 54% for MSM.

RESULTS

The annual cost of PrEP provision ranges between $75 and $134 per person. PrEP provision adolescents and young adults, regardless of risk behaviour, will each avert 3.2--4.8% of HIV infections over 20 years; provision to high-risk individuals only has similar impact at lower total cost. The incremental cost per HIV infection averted is lower in high-risk vs. all-risk sub-populations within female adolescents ($507 vs. $4537), male adolescents ($2108 vs. $5637), young women ($1592 vs. $10 323) and young men ($2605 vs. $7715), becoming cost saving within 20 years for high-risk adolescents, young women, MSM and FSWs.

CONCLUSION

PrEP is an expensive prevention intervention but uptake by those at the highest risk of HIV infection will make it more cost-effective, and cost-saving after 14-18 years.

A modeling framework to inform preexposure prophylaxis initiation and retention scale-up in the context of 'Getting to Zero' initiatives

OBJECTIVE(S)

'Getting to Zero' (GTZ) initiatives aim to eliminate new HIV infections over a projected time frame. Increased preexposure prophylaxis (PrEP) uptake among populations with the highest HIV incidence, such as young Black MSM, is necessary to accomplish this aim. Agent-based network models (ABNMs) can help guide policymakers on strategies to increase PrEP uptake.

DESIGN

Effective PrEP implementation requires a model that incorporates the dynamics of interventions and dynamic feedbacks across multiple levels including virus, host, behavior, networks, and population. ABNMs are a powerful tool to incorporate these processes.

METHODS

An ABNM, designed for and parameterized using data for young Black MSM in Illinois, was used to compare the impact of PrEP initiation and retention interventions on HIV incidence after 10 years, consistent with GTZ timelines. Initiation interventions selected individuals in serodiscordant partnerships, or in critical sexual network positions, and compared with a controlled setting where PrEP initiators were randomly selected. Retention interventions increased the mean duration of PrEP use. A combination intervention modeled concurrent increases in PrEP initiation and retention.

RESULTS

Selecting HIV-negative individuals for PrEP initiation in serodiscordant partnerships resulted in the largest HIV incidence declines, relative to other interventions. For a given PrEP uptake level, distributing effort between increasing PrEP initiation and retention in combination was approximately as effective as increasing only one exclusively.

CONCLUSION

Simulation results indicate that expanded PrEP interventions alone may not accomplish GTZ goals within a decade, and integrated scale-up of PrEP, antiretroviral therapy, and other interventions might be necessary.

"The Drug Will Help Protect My Tomorrow": Perceptions of Integrating PrEP into HIV Prevention Behaviors Among Female Sex Workers in Lilongwe, Malawi

Female sex workers (FSW) are disproportionately at risk for HIV. Pre-exposure prophylaxis (PrEP) is an effective HIV prevention method, yet approaches for incorporating PrEP within prevention strategies used by FSW are lacking. Semistructured focus group discussions were conducted with 44 HIV-negative FSW in Lilongwe, Malawi to explore perceptions of PrEP: acceptability, integration within HIV prevention behaviors, and barriers to use. Acceptability of PrEP was high. Motivation to use PrEP was rooted in love for one's life, anticipated negative economic effects associated with HIV acquisition. PrEP was viewed as complementary to existing norms for engaging in healthy sexual behaviors. Many felt PrEP may provide extra protection from HIV, along with condoms and frequent STI testing. Unpredictable daily lives, stigma, and side effects were barriers that could affect PrEP use. Leveraging existing HIV prevention strategies and social norms surrounding HIV prevention behaviors may positively impact PrEP uptake among FSW in Malawi and sub-Saharan Africa.

The impact, cost and cost-effectiveness of oral pre-exposure prophylaxis in sub-Saharan Africa: a scoping review of modelling contributions and way forward

INTRODUCTION

Oral pre-exposure prophylaxis (PrEP) is a new form of HIV prevention being considered for inclusion in national prevention portfolios. Many mathematical modelling studies have been undertaken that speak to the impact, cost and cost-effectiveness of PrEP programmes. We assess the available evidence from mathematical modelling studies to inform programme planning and policy decision making for PrEP and further research directions.

METHODS

We conducted a scoping review of the published modelling literature. Articles published in English which modelled oral PrEP in sub-Saharan Africa, or non-specific settings with relevance to generalized HIV epidemic settings, were included. Data were extracted for the strategies of PrEP use modelled, and the impact, cost and cost-effectiveness of PrEP for each strategy. We define an algorithm to assess the quality and relevance of studies included, summarize the available evidence and identify the current gaps in modelling. Recommendations are generated for future modelling applications and data collection.

RESULTS AND DISCUSSION

We reviewed 1924 abstracts and included 44 studies spanning 2007 to 2017. Modelling has reported that PrEP can be a cost-effective addition to HIV prevention portfolios for some use cases, but also that it would not be cost-effective to fund PrEP before other prevention interventions are expanded. However, our assessment of the quality of the modelling indicates cost-effectiveness analyses failed to comply with standards of reporting for economic evaluations and the assessment of relevance highlighted that both key parameters and scenarios are now outdated. Current evidence gaps include modelling to inform service development using updated programmatic information and ex post modelling to evaluate and inform efficient deployment of resources in support of PrEP, especially among key populations, using direct evidence of cost, adherence and uptake patterns.

CONCLUSIONS

Updated modelling which more appropriately captures PrEP programme delivery, uses current intervention scenarios, and is parameterized with data from demonstration and implementation projects is needed in support of more conclusive findings and actionable recommendations for programmes and policy. Future analyses should address these issues, aligning with countries to support the needs of programme planners and decision makers for models to more directly inform programme planning and policy.

The role of costing in the introduction and scale-up of HIV pre-exposure prophylaxis: evidence from integrating PrEP into routine maternal and child health and family planning clinics in western Kenya

INTRODUCTION

Understanding the cost of strategies to reach and deliver pre-exposure prophylaxis (PrEP) to priority populations is essential to assess the cost-effectiveness and budget impact of HIV prevention programmes. Providing PrEP through maternal and child health and family planning clinics offers a promising strategy to reach women in high HIV burden settings. We estimated incremental costs and explored the cost drivers of integrating PrEP delivery into routine maternal and child health and family planning services in Kenya.

METHODS

We conducted a costing study from the provider perspective within the PrEP Implementation for Young Women and Adolescents programme in western Kenya. We identified all within- and above-facility activities supporting PrEP delivery and measured clinical service time using time-and-motion studies. We obtained input costs from programme budgets, expenditure records and staff interviews. We estimated changes in costs if creatinine testing were postponed from initiation to first follow-up visit and if PrEP were prioritized to clients at high HIV risk using a behavioural risk assessment tool. We also projected costs under Ministry of Health (MOH) implementation assuming MOH salaries and programme supervision. We estimated annual numbers of PrEP visits from programme data abstracted from 16 facilities between November 2017 and June 2018. We report the cost per client-month of PrEP dispensed in 2017 USD.

RESULTS

For an annual programme output of 24,005 screenings, 4198 PrEP initiations and 4427 follow-up visits, the average cost per client-month of PrEP dispensed in the study was $26.52. Personnel, drugs and laboratory tests comprised 43%, 25% and 14% of programme costs respectively. Postponing creatinine testing and prioritizing PrEP delivery to clients at high HIV risk reduced total programme costs by 8% and 14% respectively. In the MOH scenario assuming no changes in outputs, the projected cost per client-month of PrEP dispensed decreased to $16.54 and total programme costs decreased by 38%.

CONCLUSIONS

Incremental PrEP costs are sensitive to the service delivery strategy used to engage priority populations. Postponing creatinine testing and prioritizing PrEP delivery to clients at high HIV risk may reduce costs. Context-specific cost data are crucial to assess the cost-effectiveness and affordability of PrEP delivery models.

HIV pre-exposure prophylaxis for adolescent girls and young women in Africa: from efficacy trials to delivery

INTRODUCTION

Adolescent girls and young women (AGYW) in Africa have high HIV incidence despite scale-up of HIV testing and HIV treatment. Placebo-controlled trials of tenofovir-based pre-exposure prophylaxi (PrEP) in diverse populations demonstrated that PrEP works with close to 100% effectiveness if taken with high, but not perfect, adherence. Divergent efficacy estimates among African AGYW led to demonstration and implementation projects to better understand motivations for HIV prevention, uptake, adherence and persistence to PrEP. To inform PrEP programmes, the design and initial findings from PrEP demonstration projects for AGYW are reviewed.

DISCUSSION

Early lessons from PrEP implementation projects among young African women include: (1) awareness and demand creation with positive messaging about the benefits of PrEP are critical to motivate AGYW to consider this novel prevention technology and to foster awareness among peers, partners, parents and guardians to support AGYW's effective PrEP use; (2) PrEP initiation is high in projects that are integrating PrEP into youth-friendly clinics, family planning clinics and mobile clinics; (3) young African women at risk are initiating PrEP, based on behavioural characteristics, history of intimate partner violence, depression and 30% prevalence of chlamydia and/or gonorrhoea; (4) provision of youth-friendly PrEP delivery programmes that integrate reproductive health services, including contraception and the diagnosis and treatment of sexually transmitted infections, increase health impact; (5) messages that emphasize the necessity for high adherence while at potential risk of HIV exposure and support strategies that addresses AGYW's adherence challenges are essential; and, (6) a substantial proportion of AGYW do not persist with PrEP, and strategies are needed to help AGYW assess their ongoing need, motivation and challenges with persisting with PrEP.

CONCLUSIONS

PrEP is feasible to implement in integrated reproductive health service delivery models to reach African AGYW. While PrEP demonstration projects indicate that women with behavioural risks and high rates of sexually transmitted diseases are initiating PrEP; effective strategies to support AGYW's adherence and persistence with PrEP are needed. Lessons learned from oral PrEP delivery, a novel first generation HIV prevention product, are relevant to longer-acting and less adherence-dependent strategies which are currently in clinical trials.

Cost-effectiveness of HIV Prevention Interventions in Sub-Saharan Africa: A Systematic Review

BACKGROUND

Sub-Saharan Africa carries the highest HIV burden globally. It is important to understand how interventions cost-effectively fit within guidelines and implementation plans, especially in low- and middle-income settings. We reviewed the evidence from economic evaluations of HIV prevention interventions in sub-Saharan Africa to help inform the allocation of limited resources.

METHODS

We searched PubMed, Web of Science, Econ-Lit, Embase, and African Index Medicus. We included studies published between January 2009 and December 2018 reporting cost-effectiveness estimates of HIV prevention interventions. We extracted health outcomes and cost-effectiveness ratios (CERs) and evaluated study quality using the CHEERS checklist.

FINDINGS

60 studies met the full inclusion criteria. Prevention of mother-to-child transmission interventions had the lowest median CERs ($1144/HIV infection averted and $191/DALY averted), while pre-exposure prophylaxis interventions had the highest ($13,267/HIA and $799/DALY averted). Structural interventions (partner notification, cash transfer programs) have similar CERs ($3576/HIA and $392/DALY averted) to male circumcision ($2965/HIA) and were more favourable to treatment-as-prevention interventions ($7903/HIA and $890/DALY averted). Most interventions showed increased cost-effectiveness when prioritizing specific target groups based on age and risk.

INTERPRETATION

The presented cost-effectiveness information can aid policy makers and other stakeholders as they develop guidelines and programming for HIV prevention plans in resource-constrained settings.

Mathematical modelling to inform 'treat all' implementation in sub-Saharan Africa: a scoping review

OBJECTIVE

Despite widespread uptake, only half of sub-Saharan African countries have fully implemented the World Health Organization's 'treat all' policy, hindering achievement of global HIV targets. We examined literature on mathematical modelling studies that sought to inform scale-up and implementation of 'treat all' in sub-Saharan Africa.

METHODS

We conducted a scoping review, a research synthesis to assess emerging evidence and identify gaps, of peer-reviewed literature, extracting study characteristics on 'treat all' policies and assumptions, setting, key populations, outcomes and findings. Studies were narratively summarised and potential gaps characterised.

RESULTS

We identified 16 studies examining 'treat all' alone (n=12) or with expanded testing (n=7) and/or care continuum improvements (n=6). Twelve studies examined 'treat all' for Southern African countries, while none did so for Central Africa. Four included the role of resistance; one evaluated any key population. A range of health and economic outcomes were reported, although fewer studies formally assessed budget impact. Fourteen studies involved co-authors with any in-country affiliation; one study also had co-authors with local government affiliation. Overall, 'treat all' improves health outcomes and is cost-effective compared to deferred HIV treatment; 'treat all' with expanded testing or care continuum improvements may provide further health benefits. However, studies generally used optimistic assumptions about the implementation of expanded testing or care continuum improvements.

CONCLUSIONS

The modelling literature demonstrates improved health and economic benefits of 'treat all'. Using mathematical modelling to inform real-world implementation of 'treat all' requires realistic assumptions about expanded testing and care continuum interventions across a wide range of settings and populations.

Interest in HIV pre-exposure prophylaxis in men who have sex with men in West Africa (CohMSM ANRS 12324 - Expertise France)

OBJECTIVE

To explore the interest in taking PrEP among Western African men who have sex with men (MSM).

METHODS

A cross-sectional survey was implemented at enrolment of HIV-negative MSM in a multiple centre community-based cohort study in four West African countries (Mali, Côte d'Ivoire, Burkina Faso, Togo). A standardised face-to-face questionnaire collected data on socio-demographic and behavioural characteristics over the previous 6 months. Descriptive analysis and multivariate logistic regression helped identify factors associated with the interest in taking PrEP.

RESULTS

Of 564 participants, 87% were interested in taking PrEP. Interest in PrEP was associated with inconsistent condom use for anal sex (adjusted odds ratio (aOR): 2.11; 95% confidence interval (CI) 1.21-3.67), transactional sex (aOR: 2.02; 95% CI 1.11-3.71), searching for male sexual partners on the Internet in the previous month (aOR: 1.86; 95% CI 1.01-3.43), having a high level of self-esteem (aOR: 1.20; 95% CI 1.06-1.36), having at least one sexually transmitted infections at enrolment (aOR: 5.08; 95% CI 1.40-18.4) and not being aware of PrEP (aOR: 2.03; 95% CI 1.04-3.96). Participants having sex with HIV-positive male partners (aOR: 0.28; 95% CI 0.11-0.74), those being more sexually attracted to women than to men (aOR: 0.20; 95% CI 0.07-0.89) and those reporting psychological and material support from close friends (aOR: 0.33; 95% CI 0.15-0.73) were less interested in taking PreP.

CONCLUSIONS

Western African HIV-negative MSM appear very interested in taking PrEP, especially those most at risk of HIV infection. PrEP implementation in a comprehensive prevention package should be considered urgently.

Temporal stability of HIV prevalence in high-burden areas regardless of declines in national HIV prevalence in Malawi and Zimbabwe

: The current study aims to assess the subnational temporal trends in HIV prevalence in Malawi and Zimbabwe. Using data from three Demographic and Health Surveys (DHS) conducted in Malawi and Zimbabwe, we found that national HIV prevalence in both countries substantially declined, large declines occurred in areas where HIV prevalence was already low, and HIV prevalence in high-burden areas remained stable over time. Well designed HIV prevention programmes targeting hotspots are required for effective HIV control in countries with declining HIV prevalence.

HIV prevention strategies and risk of infection: a model-based analysis

Risk populations for HIV infections tend to neglect condom use, making alternative preventive approaches necessary. Accordingly, we modelled the risk of sexual HIV transmission for condom use vs. use of rapid diagnostic test (RDT) systems with subsequent exclusion of potential sexual partners with a correctly or falsely positive test from unprotected sex with and without the use of HIV pre-exposure prophylaxis (PrEP) in a bio-statistical approach. We combined a previously described model of transmission risk for HIV-exposed individuals with a newly suggested model of risk of HIV exposure for sexually active HIV-negative individuals. The model was adapted for several stages of infection and different strategies of HIV infection prevention.HIV prevention with RDTs can reduce the transmission risk by up to 97% compared with having sex without any prevention and up to 80% compared with condom use. Nevertheless, RDT-based prevention strategies demonstrate a lack of protection in several stages of infection; in particular, RNA-based RDT systems may fail under treatment. RDT-based pre-screening of potential sex partners prior to unprotected sexual contacts substantially reduces HIV transmission risk. Combination of different prevention strategies is advisable for high-risk groups.