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Regimen Simplification
Î Change from a suppressive regimen to reduce pill burden and
dosing frequency, enhance tolerability, decrease specific food and
fluid requirements, reduce drug-drug or drug-food interactions
or dyslipidemia, and take advantage of coformulations. As a
consequence, regimen simplification can improve quality of life,
maintain adherence, avoid long-term toxicities, and reduce risk of
virologic failure.
Î Potential candidates for simplification are:
• Patients receiving regimens no longer recommended as preferred or alternative
• Patients who were prescribed a regimen in a setting of treatment failure with
incomplete understanding of resistance or drug interaction data
• Patients who were prescribed a regimen prior to the availability of newer options
or formulations that might be easier and/or more tolerable.
Types of Treatment Simplification
Within-Class Simplifications
Î A within-class substitution preserves other classes for future
regimens. It typically uses a newer agent, coformulated drugs, or a
formulation with lower pill burden, lower dosing frequency, or less
toxicity.
• NRTI substitutions: Consider if no history of viral resistance on NRTI-containing
regimen.
• NNRTI substitutions: Consider to reduce dosing frequency or to use
coformulated agents.
• Protease inhibitor (PI) substitutions: Can be from one PI to another, to the same
PI at a lower dosing frequency, or to administer without RTV boosting. (ATV
only: NOT a preferred regimen and NOT recommended for patients taking TDF
or with reduced ATV susceptibility.)
Out-of-Class Substitutions
Î Changing from a PI-based to an NNRTI-based regimen is a common
out-of-class substitution.
Î INSTIs, RAL, and MVC can also be used for out-of-class substitutions,
especially if there is a history of resistance to older HIV drugs.
Î Patients virologically suppressed on ENF-containing regimens may
wish to substitute an active oral agent (eg, RAL, ETR, or MVC).
Î In ART-experienced patients, use RAL with caution as a substitute for
a boosted PI.
Monitoring After Treatment Simplification
Î Assess tolerability, virus load, CD4 count, and renal and liver function
2–6 weeks after simplification, and fasting lipids within 3 months.
