Related Experiment Video
Updated: Jan 6, 2026
Rapid Screening of HIV Reverse Transcriptase and Integrase Inhibitors
Published on: April 9, 2014
Factors associated with the number of drugs in darunavir/cobicistat regimens
Esteban Martinez1, Eugenia Negredo2, Hernando Knobel3
1Hospital Clinic de Barcelona, University of Barcelona, Barcelona, Spain.
Background:
Darunavir/cobicistat can be used as mono, dual, triple or more than triple therapy.
Objectives:
To assess factors associated with the number of drugs in darunavir/cobicistat regimens.
Methods:
A nationwide retrospective cohort study of consecutive HIV-infected patients initiating darunavir/cobicistat in Spain from July 2015 to May 2017. Baseline characteristics, efficacy and safety at 48 weeks were compared according to the number of drugs used.
Results:
There were 761 patients (75% men, 98% were antiretroviral-experienced, 32% had prior AIDS, 84% had HIV RNA <50 copies/mL and 88% had ≥200 CD4 cells/mm3) who initiated darunavir/cobicistat as mono (n=308, 40%), dual (n=173, 23%), triple (n=253, 33%) or four-drug (n=27, 4%) therapy. Relative to monotherapy, triple therapy was more common in men aged <50 years, with prior AIDS and darunavir plus ritonavir use, and with CD4 cells <200/mm3 and with detectable viral load at initiation of darunavir/cobicistat; dual therapy was more common with previous intravenous drug use, detectable viral load at initiation of darunavir/cobicistat and no prior darunavir plus ritonavir; and four-drug therapy was more common with prior AIDS and detectable viral load at initiation of darunavir/cobicistat. Monotherapy and dual therapy showed a trend to better virological responses than triple therapy. CD4 responses and adverse effects did not differ among regimens.
Discussion:
Darunavir/cobicistat use in Spain has been tailored according to clinical characteristics of HIV-infected patients. Monotherapy and dual therapy have been common and preferentially addressed to older patients with a better HIV status, suggesting that health issues other than HIV infection may have been strong determinants of its prescription.
Related Concept Videos
01:29Therapeutic Drug Monitoring: Affecting Factors
01:19Factors Affecting Drug Distribution: Miscellaneous Factors
Age plays a significant role due to differences in body composition among different age groups. Infants, for instance, have a higher proportion of total body water and lower albumin levels, a protein that binds drugs in the bloodstream. This unique composition in infants enhances the...
01:21Factors Affecting Drug Response: Overview
01:18Factors Affecting Protein-Drug Binding: Drug-Related Factors
One crucial factor in drug-protein binding is the drug's lipophilicity or its affinity for fat. More lipophilic drugs tend to have higher binding extents. For example, highly lipophilic drugs like cloxacillin exhibit substantial protein binding, with as much as 95% of the drug binding to proteins. In...
01:19Factors Affecting Drug Biotransformation: Biological
Species differences: Variations in enzyme systems across species can cause disparities in drug metabolism. For instance, humans may metabolize certain drugs faster than rodents, altering therapeutic effects.
Strain differences: Genetic variations within a species can result in differing enzyme activity, impacting drug response and toxicity. For example, some mouse strains may...
01:28Factors Influencing Drug Absorption: Pharmaceutical Parameters