Given that official U.S. HIV treatment guidelines so strongly recommend first-line antiretroviral therapy regimens that feature integrase inhibitors, baseline HIV genotyping at diagnosis is no longer cost-effective, a modeling study published in Clinical Infectious Diseases concluded.
Genotype testing, which determines whether a person's particular strain of HIV is already resistant to specific antiretroviral medications, would only alter drug selection for a small subset of people, the study determined -- and would add less than one quality-adjusted life day per person on average. Given that the test costs $500 per person, the researchers' model predicted an incremental cost-effectiveness ratio (ICER) of $420,000 per quality-adjusted life year (QALY). That's compared to a 2005 analysis, conducted prior to the first U.S. approval of an HIV integrase inhibitor, which found an ICER of $23,900 per QALY for baseline genotyping.
In the U.S., an ICER below $50,000 is commonly considered cost-effective. Given the comparatively limited medication choices in 2005, routine genotyping prevented enough treatment failures to be considered cost-effective at the time. However, integrase inhibitors are the vanguard of a generation of newer drugs with far higher barriers to resistance; thus, such testing no longer prevents enough virologic failures to be cost-effective, authors of the current study argue.
The authors called for reconsidering the current U.S. recommendation of baseline genotyping at diagnosis. However, they cautioned that their model applies only to current treatment recommendations in the U.S. and may not apply to future therapies or in countries where integrase inhibitor-based therapy is not considered an accessible preferred option.