Bone mass higher in HIV+ children on efavirenz than lopinavir/ritonavir

Children with HIV (HIV+) who switched to efavirenz had higher bone mass even after 4 years of switching compared with those who remained on an antiretroviral therapy (ART) regimen comprising lopinavir and ritonavir, according to data presented at CROI 2020.

“This analysis presents 2 additional years of follow up [and supports our] previous report [showing that] South African [HIV+] children [who] remained on a lopinavir/ritonavir-based ART … had lower bone mass compared with HIV+ children who switched to efavirenz and children [without HIV (HIV-)],” said the researchers. [AIDS 2016;30:2459-2467]

The CHANGES Bone Study enrolled 440 children (mean age at baseline 6.7 years, 51.8 percent male) from Johannesburg, South Africa. Of these, 202 were HIV+ who either switched to efavirenz (n=107) or remained on lopinavir/ritonavir (n=95), while 202 were HIV-. Total body bone mineral content (TB-BMC) was evaluated using dual-energy X-ray absorptiometry. TB-BMC Z-scores were adjusted for age, sex, height, and race. [CROI 2020, abstract 821]

Over the 2-year follow up period, TB BMC Z-scores dropped at a rate of -0.12, -0.13 and -0.11 per year for HIV+ children on efavirenz, HIV+ children on lopinavir/ritonavir, and HIV- subjects, respectively.

TB BMC Z-scores were significantly higher among HIV+ children on efavirenz compared with those on lopinavir/ritonavir at baseline (-0.77 vs -1.14), at 1 year (-0.94 vs -1.34), and at 2 years (-1.01 vs -1.40; p<0.01 for all).

Compared with HIV- children, HIV+ children who switched to efavirenz had similar TB BMC Z-scores across all timepoints (-0.77 vs -0.82; p=0.54 [baseline], -0.94 vs -0.95; p=0.95 [1 year], -1.01 vs -1.04; p=0.71 [2 years]).

Despite early initiation of a potent ART regimen among virally suppressed South African HIV+ children, bone mass, formation, and resorption remain lower compared with HIV- children, noted the researchers. [Arch Osteoporos 2018;13:40] The consistent bone accrual benefit achieved with efavirenz underscores its potential in improving these bone conditions in this patient setting, noted the researchers.

“Although these findings reflected a slight overall decline in bone mass among HIV+ children compared with US population norms, [our] findings support our previous recommendations to switch children with sustained viral suppression on first-line regimen with lopinavir/ritonavir to efavirenz,” they concluded.