Reduced-dose efavirenz (400 mg) is non-inferior to standard-dose efavirenz (600 mg) for HIV treatment and may be less toxic. Pregnancy impacts efavirenz pharmacokinetics, however the question remains as to whether efavirenz exposure at the reduced dose is adequate for pregnant women?

Pregnancy is associated with a minimal decrease in total efavirenz exposure, but predicted free (pharmacologically active) exposure is not decreased.

Reduced-dose efavirenz likely provides adequate efavirenz exposure during pregnancy.