Matilu Mwau, M.D., MTM, D.Phil(Oxon) Performance and usability of INSTI, a blood-based rapid HIV self test for qualitative detection of HIV antibodies in intended use populations in Kenya Matilu Mwau, M.D., MTM, D.Phil(Oxon) mmwau@kemri.org

Kenya in 2015 Kenya 1.5 million PLWHIV 5.9% adult HIV prevalence Some counties >25% eg Homa Bay 78,000 new infections 58% of infected adults are on ART 83% HIV+ unaware of partners’ status May, 2017, PrEP approved -“Be Self Sure” HIV self testing program

Study Objectives Determine the performance and usability of the INSTI blood-based HIV self test (bioLytical Laboratories, Richmond, BC, Canada) for an intended-use self test population in Kenya. Device performance Label comprehension Readability Results interpretation

INSTI HIV Self Test Key Features Same platform as INSTI HIV-1/HIV-2 Ab Test Blood-based Use a 50uL free-flowing blood drop fingerstick collection Sensitivity 100% Specificity 99.8% 4

Procedure (English and Swahili) INSTI Self Test Procedure (English and Swahili) Sample. Pour. 60s 5

Study site and design Site: Western Kenya (Busia County) Matayos, Bumutiru,Khunyangu, Aterait and Asinge villages Time: 22nd Mar -11Apr 2017 688 study participants 554 consented for fingerstick and venous blood draws 134 consented for fingerstick only 354 participated in the label comprehension (usability) study 91 subjects completed the results interpretation study

Accuracy (1) Fingerstick blood used for observed self testing 476 participants completed accuracy study 201 known HIV positive. Demographics, > 18 years of age, able to provide informed consent, able to read, write and speak English/Swahili Fingerstick blood used for observed self testing Venous blood sent to KEMRI Lab for Bioelisa HIV-1+2 Ag/Ab kit (Biokit S.A, Barcelona, Spain) INSTI HIV Self Test results produced by subjects Self Test results interpreted and recorded by HCW

Accuracy (2) Subject HIV Status INSTI Negative Positive Total 267 2 269 3 198 201 Invalid 6 6* 270 206 476 INSTI Sensitivity: 198/201 = 98.5% (95.7-99.5%) INSTI Specificity: 267/269 = 99.26% (97.3-99.8%) * Invalid results not used in the calculations

Usability Results (n=350) Observed IFU Element Subject Completed Correctly Preparation of finger fingerstick 346 (98.9%) Correct use of lancet with no assistance 291 (83.1%) Correct use of lancet with assistance 58 (16.6%) Able to form “hanging” blood drop on finger with no assistance 348 (99.4%) Able to easily get the blood drop to fall into INSTI sample diliuent 349 (99.7%) Properly mixed and added sample diluent/blood to INSTI blotted membrane unit Correctly completed remaining INSTI test procedure University: 22. Secondary: 123. Primary. 152. No formal education. 48. Not recorded. 5. 354 participants were recruited and 350 completed the survey-based usability, label comprehension and ease of use elements as observed and recorded by the health care staff

Acceptability (n=350) Questionnaire Item Responses Used the INSTI instructions for use to perform the test 343 (98.0%) Found instructions easy to comprehend 339 (96.9%) Considered the INSTI test easy to perform 330 (94.3%) Found results interpretation easy to comprehend 342 (97.7%) Indicated willingness to use INSTI again Would recommend INSTI to partner, family 344 (98.3%)

INSTI Results Readability(n=91) Correct Interpretation (n=91) Strong Positive 91 (100%) Weak Positive 31 (34.1%)* Negative Invalid (no control spot) Subjects were asked to interpret a range of INSTI results using the IFU for contrived membrane cartridges representing strong positive, weak positive, negative and invalid results. * The remaining 65.9% of subjects saw the weak spot but were unsure on how to interpret the result

Conclusions INSTI PPV=89.3%, INSTI NPV=99.9% Based on the performance of the INSTI HIV Self Test in this study HIV prevalence in Kenya of 5.9%: INSTI HIV Self Test device performance meets the Kenya MoH threshold. Overall label comprehension is high (96.9%) 57.1% of participants had primary or no formal education. In the usability study, more males (206) than females (142) took part likely due to the use of county administration and village events to mobilize participants Poor interpretation for the weak positive result ? discordance in the IFU image between the English and Swahili versions. The manufacturer has revised the IFU to provide more clear instructions on weak positive interpretation.

Acknowledgements Priska Bwana Lydia Ochieng Alupe HIV Lab KEMRI HQ HIV Lab