CPIC® Guideline for Efavirenz based on CYP2B6 genotype

Most recent guideline publication:

Clinical Pharmacogenetics Implementation Consortium (CPIC) Guideline for CYP2B6 and Efavirenz-containing Antiretroviral Therapy (April 2019)

Updates since publication:

No updates on dosing recommendations since publication.

Tables and figure provided in the main manuscript of the guideline:

Table 1. Assignment of likely CYP2B6 phenotypes based on genotypes
Table 2. Efavirenz dosing recommendations  based on CYP2B6 phenotype for children ≥ 40 kg and adult patients
Figure 1. Schematic representation of efavirenz metabolism and mechanism of action against HIV

Supplement to: Clinical Pharmacogenetics Implementation Consortium (CPIC) Guideline for CYP2B6 and Efavirenz-containing Antiretroviral Therapy (April 2019) 

Tables and figures provided in the supplement or referenced in the guidelinea:

Supplemental Table S1. Evidence linking CYP2B6 genotype to efavirenz phenotype
Figure S1. Apparent oral clearance (CL/F) of efavirenz (600 mg/day) in HIV-positive individuals genotyped for CYP2B6 variants
CYP2B6 allele definition table
CYP2B6 allele functionality table
CYP2B6 frequency table
CYP2B6 diplotype-phenotype table

Gene Resource Mapping

CYP2B6 gene resource mappings

Drug Resource Mapping


Clinical Decision Support:b

Efavirenz pre- and post-test alerts and flow chart

aSome of the tables included in the guideline may have been updated online, particularly to reflect newly described or newly characterized alleles. These include the gene-specific information tables ( that support CPIC guidelines by providing information regarding star (*) allele definitions, allele function, allele frequency by major ethnic groups, translations of diplotype to phenotype, and gene resource mappings.

bThese resources support the adoption of CPIC guidelines into the electronic health record with clinical decision support and provide information that clinical implementers find helpful.