Antivirals

Antivirals and pharmacogenetics

Also known as: HIV medications, Antiretrovirals

3 medications 5 brand products CYP2B6

Why pharmacogenetics matter for antivirals

The biggest pharmacogenetic story in antivirals is HLA-B*57:01 screening before abacavir, which essentially eliminated a previously common and sometimes fatal hypersensitivity reaction.^[1] This is one of the cleanest clinical wins in all of pharmacogenetics: the screening test is cheap, highly predictive, and universally adopted.^[2] Efavirenz dose adjustment based on CYP2B6 is a smaller but also well-established pharmacogenetic signal.

HLA-B*57:01 testing is now a de facto requirement before starting any abacavir-containing HIV regimen, including fixed-dose combinations like Epzicom, Trizivir, and Triumeq. Patients who test negative for HLA-B*57:01 do not develop the reaction. Gene2Rx does not test HLA-B*57:01; it is offered as a separate clinical test. Gene2Rx does report CYP2B6, which informs efavirenz dosing.^[3]

Key gene in this class

CYP2B6

Cytochrome P450 2B6

CYP2B6 handles efavirenz (an older HIV drug), bupropion, methadone, and ketamine. The most consequential allele is *6, which dramatically reduces activity and is common across many populations. Carriers accumulate much …

Medications in this class with pharmacogenetic guidelines

Each link goes to the drug's full pharmacogenetics page with CPIC and FDA phenotype recommendations.

Peginterferon Alfa 2A IFNL3 Peginterferon Alfa 2B IFNL3 Ribavirin IFNL3

Brand products in the Antivirals class

Combined products and brand names for the medications above. Each links to a pharmacogenetic breakdown.

Copegus

ribavirin

Pegasys

peginterferon alfa-2a

PegIntron

peginterferon alfa-2b

References

U.S. Food and Drug Administration. Table of Pharmacogenetic Associations (2024). fda.gov
U.S. Food and Drug Administration. Table of Pharmacogenomic Biomarkers in Drug Labeling (2024). fda.gov
PharmGKB / Stanford University. PharmGKB: The Pharmacogenomics Knowledge Base. pharmgkb.org

Which antivirals is right for your genetics?

This page covers the pharmacogenetics of antivirals in general. A Gene2Rx report tells you how your personal genotype interacts with every drug on this page.

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Informational only, not medical advice. Pharmacogenetic guidelines describe population-level patterns that inform prescribing decisions. Never start, stop, or change a medication without talking to your prescribing clinician.