Structured treatment interruptions for patients with relatively high CD4-cell counts do not commonly result in the emergence of drug-resistant virus, researchers report in the March 1 edition of Clinical Infectious Diseases.
HIV genotypic drug resistance tests were given to 20 HIV-positive patients who took a CD4-cell guided drug holiday. Only one major drug-resistance mutation emerged among the study subjects during the treatment break, according to the researchers. In four patients already carrying virus resistant to nucleoside reverse transcriptase inhibitors, the mutations conveying the resistance actually disappeared during the break. At a 48-week follow-up point after the drug holiday, none of the study subjects had virological failure; at 108 weeks, one patient in each of the treatment-break group and nonbreak control group had experienced treatment failure.
