icon-folder.gif   Conference Reports for NATAP  
  49th ICAAC
San Francisco, CA
September 12-15, 2009
Back grey_arrow_rt.gif
Once-Daily Replacement Raltegravir as Good as Twice-Daily in Pilot Trial
  49th ICAAC (Interscience Conference on Antimicrobial Agents and Chemotherapy), September 12-15, 2009, San Francisco
Mark Mascolini
People who replaced a protease inhibitor (PI) with raltegravir did as well if they took standard twice-daily raltegravir or if they later switched to once-daily raltegravir in a 125-person study [1]. Clinicians at Carlos III Hospital in Madrid saw a trend toward improved quality of life in the once-daily group.
Because the integrase inhibitor raltegravir has a long intranuclear half-life of about 29 hours, clinicians are eager to see whether it is effective and safe if taken once daily rather than twice a day. In the United States raltegravir is licensed for twice-daily use by antiretroviral-naive and experienced people.
This study focused on 125 people who replaced a PI with twice-a-day raltegravir and maintained a viral load below 50 copies. Most people switched to raltegravir from atazanavir (n = 63) or lopinavir (n = 44). Sixty-three people whose other antiretrovirals were dosed once daily later switched to once-daily raltegravir, while 62 people taking twice-daily antiretrovirals kept twice-daily raltegravir. Thus the study is not a randomized trial, even though it compares two treatment groups..
A significantly higher proportion of people in the once-daily group had HCV coinfection (57% versus 23%, P < 0.001), and total bilirubin was significantly higher in the once-daily group (1.3 versus 0.9 mg/dL, P = 0.02). There was a trend toward older age in the once-daily group (44 versus 40, P = 0.09). Fewer people in the once-daily group (76%) than in the twice-daily group (85%) were men, but this difference lacked statistical significance (P = 0.19).
Through a median follow-up of 15 months, the raltegravir regimen failed virologically in 5 people, 1 in the once-daily group and 4 in the twice-daily group, a nonsignificant difference (P = 0.74). All 5 people had a history of nucleoside failure.
Four people stopped taking raltegravir, 1 in the once-daily group (a voluntary withdrawal) and 3 in the twice-daily group (2 because of poor adherence and 1 with headache). CD4-cell gains were similar with once-daily and twice-daily raltegravir.
Laboratory safety measures did not differ significantly between the two groups, and both groups tolerated raltegravir well. Adherence exceeded 90% in both groups. The researchers detected a trend toward improved quality of life in people taking raltegravir once daily. They did not explain how they measured adherence or quality of life. Nor did they report plasma concentrations of raltegravir.
1. Mena A, Blanco F, Cordoba M, et al. A pilot study assessing raltegravir qd versus bid in HIV patients included in a simplification trial. 49th ICAAC (Interscience Conference on Antimicrobial Agents and Chemotherapy). September 12-15, 2009. San Francisco. Abstract H-920.