CVF drug levels and washout following TDF-FTC pod-IVR use.

ARV drug levels in CVF fall off rapidly following IVR removal (grey arrow) but are quantifiable for a further 2 wk. Every circular datum represents an individual sample from one of the participants (n = 6), while triangles depict samples that were BLQ of the analytical method, and values were calculated as follows: [(assay BLQ)/2]/(median swab mass). (A) TDF. (B) TFV. (C) FTC. (D) Box plots of ARV drug terminal half-lives of elimination from CVF. The box extends from the 25th to 75th percentiles, with the horizontal line in the box representing the median; whiskers represent the lowest and highest datum. Comparison of the TDF and TFV groups using an unpaired t test with Welch’s correction showed that the groups were significantly different (P = 0.0131). ARV, antiretroviral; BLQ, below the lower limit of quantitation; CVF, cervicovaginal fluid; FTC, emtricitabine; IVR, intravaginal ring; TDF, tenofovir disoproxil fumarate; TFV, tenofovir.