Table 2.

Human Immunodeficiency Virus (HIV) Test Results Associated With Delays in Detection of HIV Infection^a

	CAB Arm			TDF/FTC Arm
	Baseline: Group A (n = 4)	Incident: Group B (n = 5)	Incident: Groups C and D (n = 7	Baseline (n = 3)	Incident (n = 39)
Delay between 1st reactive qualitative RNA test and 1st reactive Ag/Ab test
Participants, no. (%)	3 (75)	0	7 (100)	3 (100)	8 (21)
Duration of delay, range, d (among those with delayed Ag/Ab test result)	14-60b	NA	35–185	14–36	7–68c
Delay between 1st reactive qualitative RNA test and 1st positive confirmatory Ab test
Participants, no. (%)	4 (100)d	1 (20)	7 (100)e	3 (100)	18 (46)f
Duration of delay, d (among those with delayed confirmatory Ab test result)	60–248d	3	36–185e	21–49	4-68c,f
Participants with assay reversion, no. (%)
Ag/Ab test (from reactive to nonreactive)	2 (50)b	0	2 (29)	0	0
Confirmatory Ab test (from indeterminate to negative)	0	0	1 (14)g	0	0
Qualitative RNA test (from reactive to nonreactive)	2 (50)	0	2 (29)	0	0

Abbreviations: Ab, antibody; Ag, antigen; CAB, cabotegravir; NA, not applicable; TDF/FTC, tenofovir disoproxil fumarate–emtricitabine.

^aTable 2 shows the delays observed for different human immunodeficiency virus (HIV) test outcomes at the HIV Prevention Trials Network (HPTN) Laboratory Center for the participant groups described in Table 1. The table also shows the number of cases in which reversion of test results was observed for the Ag/Ab test, the confirmatory Ab test, and the qualitative RNA test. Data are shown for visits before initiation of antiretroviral therapy (ART).

^bOne case did not have a reactive Ag/Ab test after 41 days of follow-up.

^cExcludes 1 case with a 372-day visit window.

^dTwo cases did not achieve a positive confirmatory Ab test (longest pre-ART follow-up, 98 days).

^eThree cases did not achieve a positive confirmatory Ab test (longest pre-ART follow-up, 333 days).

^fEight cases did not achieve a positive confirmatory Ab test (longest pre-ART follow-up, 14 days).

^gThis participant did not achieve a positive confirmatory Ab test after 333 days of follow-up.