Resistance in Patients Failing Integrase Strand Transfer Inhibitors: A Call to Replace Raltegravir with Dolutegravir in Third-Line Treatment in South Africa

Data on integrase resistance patterns in low- and middle-income countries (LMICs) is scarce. We assessed genotypic drug resistance in 43 patients with virological failure on integrase strand transfer inhibitors (INSTIs) containing regimens as part of the third-line treatment program in South Africa. Of the raltegravir (RAL)-exposed patients 20 of 34 (59%) had ≥1 major INSTI mutation, including 2 (6%) with dolutegravir (DTG) cross-resistance. Dolutegravir resistance was detected in 1 of 4 DTG-exposed patients. Replacing RAL with DTG may reduce the risk of INSTI mutations. We recommend DTG drug resistance monitoring when DTG is introduced at a larger scale in LMICs.