Study: Triple-nucleoside combination works
Study: Triple-nucleoside combination works
Two studies comparing the triple-nucleoside regimen of abacavir sulfate plus lamivudine/ zidovudine with triple-drug regimens containing protease inhibitors as first-line antiretroviral therapy in therapy-naive patients found the triple-nucleoside regimen effective and patient tolerance and adherence high, researchers told colleagues at the recent XIII International AIDS Conference in Durban, South Africa.
In a study of 342 antiretroviral-naive patients, patients were randomized to receive either the triple-nucleoside regimen of abacavir sulfate plus lamivudine/zidovudine or indinavir plus lamivudine/zidovudine for 48 weeks. Patients on the first regimen took one abacavir sulfate and one lamivudine/zidovudine twice a day without dietary restrictions. Patients on the nucleoside plus protease inhibitor regimen took two indinavir tablets every eight hours and one lamivudine/zidovudine tablet twice daily. The patients taking indinavir were required to take the tablets one hour before or two hours after a meal and drink one and a half quarts of water a day.
Patients were stratified according to baseline plasma viral load, with 63% having a viral load greater than 5,000 copies/ml but less than 100,000 copies/ml, and 37% having a viral load greater than 100,000 copies/ml.
At 24 weeks, 68% of patients on abacavir sulfate plus lamivudine/zidovudine had a viral load of less than 400 copies/ml, compared with 57% on the indinavir plus lamivudine/zidovudine regimen. Of the 245 patients for whom data were available from the more sensitive <50 copies/ml assay, 79% of patients on the abacavir sulfate plus lamivudine/zidovudine regimen were below the threshold, compared with 73% on the indinavir plus lamivudine/zidovudine regimen.
Adherence findings
Other findings include:
• Among patients whose baseline viral load was less than 100,000 copies/ml at baseline, 87% of the abacavir sulfate plus lamivudine/zidovudine patients achieved a viral load of less than 50 copies/ml, compared with 81% of patients in the other group.
• In patients whose baseline viral load was above 100,000 copies/ml, 65% in the abacavir sulfate plus lamivudine/zidovudine group achieved a viral load of <50 copies/ml, compared with 63% in the other group.
Adherence was self-reported by patients using the Treatment Assessment and Satisfaction Questionnaire, a validated measure of adherence. Researchers found that 74% of patients on the abacavir sulfate plus lamivudine/zidovudine regimen reported taking all antiretroviral doses over the previous four weeks or missed less than one dose per week, compared with 45% of patients in the indinavir plus lamivudine/zidovudine group. Only 6% of patients in the abacavir sulfate plus lamivudine/zidovudine group reported that their regimen was difficult to take as scheduled, compared with 38% in the other group.
"These early data offer important information about this triple-nucleoside regimen," says Pedro Cahn, MD, director of Fundacion Huesped in Buenos Aires, Argentina, and principal investigator of the study.
In a second study by French researchers, 195 patients were randomized to receive either one abacavir sulfate tablet plus one lamivudine/ zidovudine tablet twice a day without dietary restrictions or three nelfinavir tablets every eight hours and one lamivudine/zidovudine tablet twice a day for 48 weeks. The median CD4 cell counts at baseline were 387 cells/ml in the first group and 449 cells/ml in the second group.
Findings include:
• 67% of patients in the abacavir sulfate plus lamivudine/zidovudine group had a viral load below 50 copies/ml and 72% had viral load below 400 copies/ml, compared with 66% below 50 copies/ml and 71% below 400 copies/ml in the other group.
• The median CD4 cell count increase was 91 cells/mm3 in the abacavir sulfate plus lamivudine/zidovudine group and 65 cells/mm3 in patients the other group.
• Ten patients on the abacavir sulfate plus lamivudine/zidovudine group experienced serious adverse events, including anemia, retinal detachment, and acute confusional psychosis.
• Four patients on the nelfinavir plus lamivudine/zidovudine group experienced serious adverse events, including depression, diarrhea, and hepatic cytolysis.
Abacavir sulfate is manufactured under the brand name Ziagen by Glaxo Wellcome in Research Triangle Park, NC. Lamivudine/zidovudine is also a Glaxo product manufactured under the brand name Combivir. For details on either drug, visit www.glaxowellcome.com or drug- specific sites at www.ziagen.com and www. combivir.com.
Subscribe Now for Access
You have reached your article limit for the month. We hope you found our articles both enjoyable and insightful. For information on new subscriptions, product trials, alternative billing arrangements or group and site discounts please call 800-688-2421. We look forward to having you as a long-term member of the Relias Media community.