An observed, prospective field study to evaluate the performance and acceptance of a blood-based HIV self-test in Canada

Abstract

Background Self testing for HIV is a targeted intervention with the potential to increase the access, uptake and frequency of HIV testing and more effectively reach the undiagnosed, especially in priority populations. The objectives of this study were to (1) evaluate the INSTI HIV self-test performance compared with laboratory reference testing, (2) document if intended users can perform the steps to use the HIV self-test device, and (3) document if intended users can successfully interpret contrived positive, negative, and invalid results. Study was intended to be submitted to Health Canada for review for regulatory approval purposes. Methods The study used a cross-sectional design and recruited consenting adults who were representative of intended users of HIV self-testing from four community sites across Ontario, Québec, and Manitoba between August 2019 and March 2020. The results of the observed HIV self-test were compared with results of the Abbott Architect HIV Ag/Ab Combo test. Usability outcomes for critical (e.g., lancing finger, blood droplet into bottle, shaking bottle four times) and noncritical self-test procedure steps were also determined. Results Overall, 77% (n = 522) of participants were between 18 and 45 years of age, 61% (n = 410) were male, 71% (n = 480) had some college or more education, and 45% (n = 307) were employed; identity for race and ethnicity: Caucasian (44%; n = 296), African, Caribbean or Black (17%; n = 113), Indigenous [First Nations, Métis or Inuit] (14%; n = 95), Asian (16%; n = 106), Latin American (7%; n = 46). Primary performance analysis on 678 completed HIV self-tests revealed a positive percent agreement of 100% (5/5, 95% CI: 43.6–97.0%) and a negative percent agreement of 99.5% (614/617, 95% CI: 98.6–99.8%) with the comparator method. The overall percent agreement of results interpretation between participant and observer was 93.5% (n = 633). For the 708 participants who took part in the usability study, the average success rate for steps determined to be “critical” for successful completion of the test was 92.4%. 97% (n = 670) of participants found the instructions easy to follow, and 95% (n = 655) of participants indicated that they would use the test again. Of the 404 participants who interpreted the strong positive, weak positive, negative, and invalid contrived results, successful interpretation ranged from 90.6% (for weak positive, n = 366) to 99.3% (for negative, n = 401). Conclusions The addition of a regulatory-approved self-test into the Canadian HIV testing landscape could significantly increase HIV testing rates. Having a blood-based HIV self-test approved in Canada can offer an accurate, acceptable, and simple alternative to facility-based HIV testing, particularly when impacted by Coronavirus pandemic restrictions.

Invalid Results in the GetaKit Study in Ottawa: A Real-World Observation of the INSTI® HIV Self-test Among Persons At Risk for HIV

“…That our final invalid rate matches the overall test failure rate of Galli et al (2021) suggests that regulators and policy makers should review, approve, and select HIV self-tests based on the combined performance metrics of true test performance (i.e., true invalid results confirmed by a trained observer) plus users' inability to read test results, even if these results would be interpreted as valid by a trained observer. Our results suggest-and align with the work by Galli et al (2021)-that we might expect an approximately 8% test failure rate for the INSTI® self-test. This finding further suggests that, although HIV self-testing is intended to be done by oneself, additional supports and resources are likely needed to facilitate accurate device usage.…”

“…For one, our study identified a higher invalid rate for the INSTI® HIV self-test than what exists in the literature (Galli et al, 2021;Majam et al, 2021). Majam et al (2021) reported an invalid rate of 0.3% (n 5 3/900) for this test in their clinic-based study in which participants were observed and evaluated while performing the test.…”

“…Bwana et al (2018) reported an invalid rate of 1.26% from their study, in which participants first received a demonstration on how to perform the test in a clinic setting and were then observed performing the test. Galli et al (2021) reported an invalid rate of 5.6% for the same device, again in a clinic-based study involving direct observation of participants while they performed the test. Our overall invalid rate, in comparison, was 12%, which decreased to 8% after we began providing participants with additional instructions about completing the test.…”

“…One interpretation of these data is that, although the INSTI® HIV self-test may be (1) highly sensitive and specific as a device (Bwana et al, 2018; Galli et al, 2021; Majam et al, 2020; Mourez et al, 2018) and (2) easy to use by those who agree to perform the test in a controlled setting while being observed and evaluated, (3) it seems to have lower performance in the real-world when participants use this test alone in a setting of their choosing. It is possible that persons who agree to be evaluated in a research or clinic setting while performing the test are not the same as those who self-test by themselves at home or elsewhere, and that data from controlled settings cannot be extrapolated from observed to unobserved settings.…”

Laboratory Industry Perspectives on the Role of Self-Collection and Self-Testing in Remote Care for Sexually Transmitted Infections: How Do We Bring These Services to Scale?

“…Examples of the former include self-collect dried blood spot mail-in kits for HIV serology 5 or self-collected rectal or pharyngeal swabs mailed in for gonorrhea/chlamydia testing 6 . Examples of the latter include the OraQuick device that is licensed in the United States for self-testing for antibodies to HIV through a buccal mucosal swab, 7 and the INSTI test, which is licensed in Canada for self-testing for antibodies to HIV in a fingerstick specimen and has the CE mark in European Union countries as a point of care test 8 . The distinction in these terms is important, because there are distinct barriers and facilitators to the implementation of the two modes of remote care testing—falling along the lines of traditional implementation frameworks, as reviewed in a separate article in this issue 3…”