Impaired creatinine-based estimated glomerular filtration rate in Thai individuals switching to dolutegravir: illustrating the role of cystatin C testing to aid clinical decision making

Introduction: Data about impact of switch to dolutegravir (DTG)-based antiretroviral therapy (ART) on estimated glomerular filtration rate (eGFR) in Asians are scarce. RV254/SEARCH010 is a prospective observational cohort in Bangkok, Thailand with ART initiation during acute HIV infection (AHI) where participants switched to DTG-based ART. Methods: Participants started Efavirenz (EFV)-based ART during AHI (n = 214) and switched to DTG-based ART after a median of 97 weeks (IQR 61–145). GFR was estimated by serum creatinine (eGFR_cre) every 24 weeks before and after switch. Estimated GFR by cystatin C (eGFR_cystC) was ordered at clinician’s discretion for decreased eGFR_cre after switch. Random-effect linear regression model was used to assess changes in eGFR_cre over 96 weeks from starting ART, and from switching to DTG. Results: At study entry, 20 participants (9.3%) had eGFR_cre < 90 ml/min/1.73 m². During EFV-based ART, an additional 17 (8%) developed eGFR_cre < 90 ml/min/1.73 m², nearly all transient, while mean eGFR_cre remained stable and within normal range. At switch to DTG, 21 (9.8%) had eGFR_cre < 90 ml/min/1.73 m² but an additional 116 (54%) developed eGFR_cre < 90 ml/min/1.73 m² during follow-up with eGFR_cre decrease being mostly persistent. Mean eGFR_cre decreased 20.8% from 117.0 to 92.4 ml/min/1.73 m² (p < 0.001). Among 20 post-switch participants with eGFR_cystC measured within 4 weeks of eGFR_cre < 90 mL/min/1.73 m², 13 (65%) had normal kidney function by eGFR_cystC. Conclusions: Persistent eGFR_cre decrease to < 90 ml/min/1.73 m² after switch to DTG was common in this Thai population. eGFR_cystC was helpful to identify individuals with clinically significant decrease in kidney function and obviate unnecessary ART modifications. Trial registration Clinical Trials Registry Number: ClininicalTrials.gov NCT00796146.