HPTN Bibliographic Record

Flys TS, Mwatha A, Guay LA, Nakabiito C, Donnell D, Musoke P, Mmiro F, Jackson JB, and Eshleman SH. Detection of K103N in Ugandan women after repeated exposure to single dose nevirapine. AIDS. 2007, 21: 2077-82 PMID 17885298.
OBJECTIVES: Use of single dose nevirapine (SD NVP) for prevention of HIV-1 mother-to-child transmission (pMTCT) is associated with selection of K103N-containing HIV variants. Repeat use of SD NVP for pMTCT may influence emergence and persistence of NVP-resistant variants. DESIGN: K103N-containing variants were studied in 48 Ugandan women who received SD NVP in the HIVNET 012 trial, and were re-exposed to SD NVP in one (n = 44) or two (n = 4) subsequent pregnancies during a 5-year follow-up study. METHODS: Samples were analyzed using the LigAmp assay (assay cutoff: 0.5% K103N). RESULTS: Among 44 women who were re-exposed to SD NVP in one subsequent pregnancy, 37.8% had K103N detected within 1 year of SD-NVP re-exposure. Detection of K103N was independently associated with detection of K103N 6-8 weeks after the first SD NVP exposure and with pre-NVP viral load. The portion of women with undetectable K103N by 2 years after SD NVP administration was similar after first versus second use of SD NVP for pMTCT. K103N was undetectable in 93.2% of evaluable women by 3 years of re-exposure. Only two of four women who received SD NVP in two pregnancies during the follow-up study had K103N detected after the last SD NVP exposure. CONCLUSIONS: K103N was detected in some women within 1 year of SD NVP re-exposure, but faded from detection in most women by 3 years after re-exposure. Detection of K103N by 1 year after SD NVP re-exposure was associated with prior selection of K103N-containing variants and with pre-NVP viral load.