BOSTON – A randomized trial in sub-Saharan Africa found no evidence that first-line raltegravir (Isentress)triggers immune reconstitution syndrome in HIV patients.
It’s an important finding because raltegravir and other integrase inhibitors are replacing nonnucleoside reverse-transcriptase inhibitors (NNRTIs) as first-line treatments for HIV. There have been a few reports from observational studies that among severely immunocompromised, the rapid drop in viral load (VL) with the drugs might trigger immune reconstitution syndrome (IRIS), an exaggerated, dysfunctional, and sometimes fatal response to pathogens as the immune system begins to recover.
Alex Otto/Frontline Medical News
Dr. Diana Gibb
The 1,805 subjects in those four countries – a few children, but mostly adults – started the trial with median baseline CD4 counts of 37 cells/mcL and VLs of 249,770 copies/mL; 903 were randomized to standard treatment with two nucleoside reverse transcriptase inhibitors plus one NNRTI (Efavirenz), while 902 were randomized to the same regimen but with raltegravir during the first 12 weeks.
As expected, VLs came down very fast in the raltegravir group to a mean of only 80 copies/mL at 4 weeks, vs. a mean of 480 copies/mL in the standard treatment arm.
After a median of about a month, 225 fatal and 113 nonfatal IRIS events (adjudicated by a review committee blinded to randomization) occurred in 9.9% of patients in the raltegravir arm and 9.5% of patients on standard treatment, a nonsignificant difference (P = .79). IRIS was fatal in 4% of raltegravir patients and 3.4% of standard-care patients, also a nonsignificant difference (P = .54).