Predictors of Treatment Failure in Children With HIV Starting First-line Antiretroviral Therapy in the ODYSSEY Trial.

BACKGROUND

Data on predictors of treatment failure in children starting antiretroviral therapy (ART) are limited, particularly on dolutegravir-based regimens (DTG).

METHODS

ODYSSEY demonstrated superior efficacy of DTG versus standard-of-care (SOC). We assessed predictors at ART initiation of treatment failure by 96 weeks.

RESULTS

Three hundred and eighty-one children started first-line ART (82% African). At ART-initiation, median age was 10.5 years (IQR: 6.5, 14.0, 67 < 3 years), CD4% 20% (IQR: 12, 28), BMI-for-age Z-score -.58 (IQR:-1.48, +.25). One hundred and eighty-nine children started DTG, 192 started SOC (91% ≥3 years started efavirenz; 79% <3 years started lopinavir). Seventy-five children experienced treatment failure (24 DTG, 51 SOC). Failure risk was lower on DTG than SOC (hazard ratio [HR] = 0.47, 95% CI: 0.29-0.77, P = .002). Lower BMI-for-age Z-score (HR = 0.82 for each unit gain, 95% CI: 0.70-0.96, P = .01) and being at an African site (HR = 2.09, 95% CI: 0.82-5.31, P = .09) were associated with higher failure risk. Risk was also higher at younger ages with the steepest increase in the youngest children and increased at lower CD4%, with a stronger CD4% effect at younger ages. At CD4% = 20, HRs relative to age 10 years were 2.40 (95% CI: 1.58-3.65) at age 1 year, 1.30 (95% CI: 1.15-1.48) at age 5 years, and 0.80 (95% CI: 0.72-0.89) at age 18 years. At age 1 year, HRs relative to CD4% = 20 were 1.39 (95% CI: 1.16-1.66) at CD4% = 15, and 0.52 (95% CI: 0.36-0.75) at CD4% = 30; at age 10, corresponding estimates were 1.07 (95% CI: 0.94-1.20) at CD4% = 15, and 0.88 (95% CI: 0.69-1.13) at CD4% = 30.

CONCLUSIONS

Young age, low BMI-for-age, and low CD4% at ART initiation predicted higher risk of treatment failure and can guide targeted support.