The clinical and cost-effectiveness of HIV self-testing in Blantyre, Malawi

Background: Human immunodeficiency virus (HIV) remains a global health problem. In sub-Saharan Africa, where the majority of HIV infected individuals live, 1.5 million HIV positive individuals die and 1.2 million become infected every year. Ensuring timely access to anti-retroviral therapy (ART) and efficacious HIV prevention strategies could potentially end the epidemic. To realise these benefits, individuals need access to frequent HIV testing and retesting. Facility-based HIV testing and counselling (HTC) is not popular in the region. HIV self-testing (HIVST), where individuals test in the privacy of their own homes, has been found to potentially achieve the required levels of HIV testing needed to achieve these goals. However no economic analysis of HIVST has been undertaken to inform policy makers whether it is a cost-effective option to scale-up in the region. Objective: To undertake a cost-utility analysis (CUA), from the health provider and societal perspectives, that estimates the incremental cost per quality-adjusted life year (QALY) gained by providing Malawian communities HIVST, in addition to routine provision of facility-based HTC. Methods: A decision-analytical model parameterised using primary cost and health-related quality of life (HRQoL) data collected from three observational studies: (1) a cross-sectional study recruiting individuals (n=1,241) who accessed HIVST and facility-based HTC; (2) a cohort study following up HIV positive individuals (n=330) accessing HIV treatment after HIVST or facility-based HTC; and (3) a cohort study of adults (n=822) admitted to the medical wards at Queen Elizabeth Central Hospital. In addition, evidence from the literature was synthesised to estimate epidemiological parameter inputs. Primary costing was undertaken to estimate health provider costs. Participants were asked about the direct non-medical and indirect costs they incurred, and their HRQoL measured using the EuroQol EQ-5D. Costs were adjusted to 2014 US and INT Dollars, and the primary cost-effectiveness outcome was expressed in terms of incremental cost per QALY gained. Results: The health provider cost per participant tested through HIVST (US$8.78) was comparable to that for facility-based HTC (US$7.53-US$10.57), although the mean societal costs of HTC were US$ 2.38 (95%CI: US$0.87-US$3.89) lower with HIVST. The mean total health provider (US$22.74 v US$28.33) and societal cost (US$25.56 v US$32.22) during the pre-ART period was lower for those who had accessed HIVST to learn their status than for those who accessed facility-based HTC. Mean total health provider and societal costs during the first year of accessing ART were comparable between those who had accessed HIVST and facility-HTC (mean total societal cost: US$251.14 v US$261.57). HIV positive individuals who had more advanced HIV disease, measured by the CD4 count, had lower EQ-5D utility scores. Health-related quality of life improved once individuals started ART, with the majority of participants reporting perfect health one year after starting ART. The mean cost of hospital admission was high, for example the mean health provider cost of managing Cryptococcal Meningitis and Pulmonary Tuberculosis was US$837.92 and US$473.11, respectively, and was associated with low EQ-5D utility scores. The CUA found the incremental cost-effectiveness ratio (ICER) of providing HIVST in addition routine facility-based HTC to be US$316.18 per QALY gained from the health provider perspective (societal perspective: US$332.05 per QALY gained). The sensitivity analysis found the ICER was comparable if the cost of HIVST was higher, if there were lower rates of linkage into HIV treatment after HIVST and if the HIV prevalence in the population was lower. Conclusion: HIVST was found to be an affordable and cost-effective option for Malawi based on International guidelines (ICER below three times the gross domestic product: US$250 in Malawi). Undertaking primary economic data collection in resource-constrained settings was feasible and provided robust estimates for use in decision-analytic models.