Cost & Cost-Effectiveness of Implementing SD Biosensor Antigen Detecting SARs-CoV-2 Rapid Diagnostic Tests in Kenya

The COVID-19 pandemic has created a need to rapidly scale-up testing services. In Kenya, services for SARS-CoV-2 nucleic acid amplifying test (NAAT) have often been unavailable or delayed, precluding the clinical utility of the results. The introduction of antigen-detecting rapid diagnostic tests (Ag-RDT) has had the potential to fill at least a portion of the ‘testing gap’. We, therefore, evaluated the cost-effectiveness of implementing SD Biosensor Antigen Detecting SARs-CoV-2 Rapid Diagnostic Tests in Kenya. We conducted a cost and cost-effectiveness of implementing SD biosensor antigen-detecting SARS-CoV-2 rapid diagnostic test using a decision tree model following the Consolidated Health Economic Evaluation Standards (CHEERS) guidelines under two scenarios. In the first scenario, we compared the use of Ag-RDT as a first-line diagnostic followed by using NAAT assay, to the use of NAAT only. In the second scenario, we compared the use of Ag-RDT to clinical judgement. We used a societal perspective and a time horizon of patient care episodes. Cost and outcomes data were obtained from primary and secondary data. We used one-way and probabilistic sensitivity analysis to assess the robustness of the results. At the point of care, Ag-RDT use for case management in settings with access to delayed confirmatory NAAT testing, the use of Ag-RDT was cost-effective (ICER = US$ 964.63 per DALY averted) when compared to Kenya’s cost-effectiveness threshold (US$ 1003.4). In a scenario with no access to NAAT, comparing the Ag-RDT diagnostic strategy with the no-test approach, the results showed that Ag-RDT was a cost-saving and optimal strategy (ICER = US$ 1490.33 per DALY averted). At a higher prevalence level and resource-limited setting such as Kenya, implementing Ag-RDT to complement NAAT testing will be a cost-effective strategy in a scenario with delayed access to NAAT and a cost-saving strategy in a scenario with no access to NAAT assay. ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Protocols [https://kemriwellcometrust-my.sharepoint.com/:w:/g/personal/barwah\_kemri-wellcome\_org/EbhHYk8oaW5Gm1-IC5PuaQwBzkpLJTy3vOb5D2AIvHhmTg?e=HLBzfF][1] ### Funding Statement The project that generated data used in this study was made possible by the generous support of the World Health Organization. The study was an implementation Research on the use of Antigen Rapid Diagnostic Tests for Coronavirus Disease 2019 (COVID-19). The study entailed the assessment of field performance, feasibility, acceptability, ease of use and impact of Ag-RDTs for the diagnosis of SARS-CoV-2 infection in Kenya. The funding was awarded to JG. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: This research was approved by the Ethics committee of Kenya Methodist University and all participants signed a written consent form to participate to the study I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes PLOS Data Policies [https://kemriwellcometrust-my.sharepoint.com/:x:/g/personal/barwah\_kemri-wellcome\_org/EcxX2qi3po5Hlj_la-GT5oUBC4aCpKvfYLnJIQa224bT-w?e=6PWOaZ][2] [1]: https://kemriwellcometrust-my.sharepoint.com/:w:/g/personal/barwah_kemri-wellcome_org/EbhHYk8oaW5Gm1-IC5PuaQwBzkpLJTy3vOb5D2AIvHhmTg?e=HLBzfF [2]: https://kemriwellcometrust-my.sharepoint.com/:x:/g/personal/barwah_kemri-wellcome_org/EcxX2qi3po5Hlj_la-GT5oUBC4aCpKvfYLnJIQa224bT-w?e=6PWOaZ