COMPARATIVE BIOAVAILABILITY OF LETROZOLE UNDER FED AND FASTING CONDITIONS IN 12 HEALTHY-SUBJECTS AFTER A 2-CENTER-DOT-5 MG SINGLE ORAL-ADMINISTRATION

Letrozole is a new non-steroidal inhibitor of the aromatase enzyme sys tem. It is currently under development for the treatment of postmenopa usal women with advanced breast cancer. To investigate the influence o f food on the bioavailability of letrozole, 12 healthy male volunteers were treated under fed and fasted conditions with single oral doses o f 2.5 mg letrozole in film-coated tablets. Plasma concentration profil es were determined. No significant difference in the extent of absorpt ion (AUG or AUC(0-8) h) was observed between the two treatments but th e rate of letrozole absorption decreased slightly under fed conditions . However, in view of the half-life of about 2 d this small change in the absorption rate is not considered to be of clinical relevance for treatment with repeated administrations. (C) 1997 by John Wiley & Sons , Ltd.