Background: As antiretroviral treatment (ART) programs mature, data on drug utilization and costs are needed to assess durability of treatments and inform program planning.
Methods: Children initiating ART were followed up in an observational cohort in Thailand. Treatment histories from 1999 to 2009 were reviewed. Treatment changes were categorized as: drug substitution (within class), switch across drug class (non nucleoside reverse-transcriptase inhibitors (NNRTI) to/from protease inhibitor (PI)), and to salvage therapy (dual PI or PI and NNRTI). Antiretroviral drug costs were calculated in 6-month cycles (US$ 2009 prices). Predictors of high drug cost including characteristics at start of ART (baseline), initial regimen, treatment change, and duration on ART were assessed using mixed-effects regression models.
Results: Five hundred seven children initiated ART with a median 54 (interquartile range, 36–72) months of follow-up. Fifty-two percent had a drug substitution, 21% switched across class, and 2% to salvage therapy. When allowing for drug substitution, 78% remained on their initial regimen. Mean drug cost increased from $251 to $428 per child per year in the first and fifth year of therapy, respectively. PI-based and salvage regimens accounted for 16% and 2% of treatments prescribed and 33% and 5% of total costs, respectively. Predictors of high cost include baseline age ≥ 8 years, non nevirapine-based initial regimen, switch across drug class, and to salvage regimen (P < 0.005).
Conclusions: At 5 years, 21% of children switched across drug class and 2% received salvage therapy. The mean drug cost increased by 70%. Access to affordable second- and third-line drugs is essential for the sustainability of treatment programs.
*Program for HIV Prevention and Treatment, Institut de Recherche pour le Développement (IRD) UMI 174-PHPT, France;
†Faculty of Associated Medical Sciences, Chiang Mai University, Thailand;
‡Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA;
§Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom;
‖Faculty of Public Health and Policy, London School of Hygiene & Tropical Medicine, London, United Kingdom;
¶Centre Population et Développement, UMR 196 CEPED, Université Paris Descartes INED-TRD, Paris, France;
#Lamphun Provincial Hospital, Lamphun, Thailand;
**Prapokklao Hospital, Chantanaburi, Thailand;
††Bhumibol Adulyadej Hospital, Bangkok, Thailand;
‡‡Hat Yai Hospital, Hat Yai, Thailand;
§§Mahasarakham Hospital, Mahasarakham, Thailand; and
‖‖Chiang Kham Hospital, Chiang Kham Thailand.
Correspondence to: Intira Collins, MSc, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom (e-mail: email@example.com).
Presented at Fourth International Workshop on HIV Pediatrics, July 20–21, 2012, Washington, DC.
Supported by The Global Fund to fight AIDS, Tuberculosis and Malaria (Thailand Grant Round 1 sub recipient PR-A-N-008); Institut de Recherche pour le Développement (IRD), France; International Maternal Pediatric Adolescents Aids Clinical Trials Group (IMPAACT); The National Institutes of Health, US (R01 HD 33326; R01 HD 39615); Ministry of Public Health, Thailand; Oxfam Great Britain, Thailand; and United Kingdom Medical Research Council Doctoral Training Account Studentship for Intira Collins.
The authors have no conflicts of interest to disclose.
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Received November 16, 2012
Accepted March 29, 2013