Thahira Jamal MohamedSirinya TeeraananchaiStephen KerrWanatpreeya PhongsamartNik Khairulddin Nik YusoffRawiwan HansudewechakulPenh Sun LyLam Van NguyenTavitiya SudjaritrukPagakrong LumbiganonViet Chau DoNia KurniatiNagalingeswaran KumarasamyDewi Kumara WatiMoy Siew FongRevathy NallusamyAzar KariminiaAnnette H. SohnKuala Lumpur HospitalThe HIV Netherlands Australia Thailand Research CollaborationMahidol UniversityHospital Raja Perempuan Zainab IIChiangrai Prachanukroh HospitalNational Center for HIV/AIDSNational Hospital of Pediatrics HanoiChiang Mai UniversityKhon Kaen UniversityChildren's Hospital 2University of Indonesia, RSUPN Dr. Cipto MangunkusumoVHS Medical Centre IndiaUniversitas UdayanaHospital LikasPenang HospitalUniversity of New South Wales (UNSW) AustraliaTREAT Asia/amfAR-The Foundation for AIDS Research2018-12-212019-03-142018-12-212019-03-142017-03-01AIDS Research and Human Retroviruses. Vol.33, No.3 (2017), 230-23319318405088922292-s2.0-85014491256https://repository.li.mahidol.ac.th/handle/20.500.14594/42842© 2017, Mary Ann Liebert, Inc. 2017. We sought to assess the impact of routine HIV viral load (VL) monitoring on the incidence of switching from a first- to a second-line antiretroviral therapy (ART) regimen, and to describe factors associated with switch. Data from a regional cohort of 16 clinical programs in six Asian countries were analyzed. Second-line switch was defined as a change from a non-nucleoside reverse transcriptase inhibitor (NNRTI) to a protease inhibitor (PI) or vice versa, and ≥1 of the following: (1) reported treatment failure by local criteria, (2) switch of ≥1 additional drug, or (3) a preceding HIV VL ≥1,000 copies/ml. Routine VL was having ≥1 test after ≥24 weeks of ART and ≥1 time/year thereafter. Factors associated with time to switch were evaluated with death and loss to follow-up as competing risks. A total of 2,398 children were included in this analysis. At ART initiation, the median (interquartile range) age was 6.0 (3.3-8.9) years, more than half had WHO stage 3 or 4, the median CD4 was 189 (47-456) cells/mm3, 93% were on NNRTI-based first-line ART, and 34% had routine VL monitoring. Treatment switch occurred in 17.6% of patients, at a median of 35 (22-49) months. After adjusting for country, sex, first ART regimen, and CD4% at ART initiation, children with routine VL monitoring were 1.46 (95% confidence interval 1.11-1.93) times more likely to be switched (p = .007). Scale-up of VL testing will lead to earlier identification of treatment failure, and it can help guide earlier switches to prevent resistance.Mahidol UniversityImmunology and MicrobiologyArticleSCOPUS10.1089/aid.2016.0039