Corifollitropin alfa doses based on body weight: clinical overview of drug exposure and ovarian response

Corifollitropin alfa is a new sustained follicle stimulant, a single injection of which can replace the conventional first seven daily injections of recombinant FSH in ovarian stimulation for IVF or intracytoplasmic sperm injection. This review is based on the results of clinical trials testing two selected doses of corifollitropin alfa for patients of different body weights, 150 g for patients weighing more than 60 kg, and 100 μg for patients weighing up to 60 kg. The relationships between patient body weight, drug exposure and ovarian response are discussed. These selected doses of corifollitropin alfa, administered according to the patient's body weight, provide, on average, equal drug exposure and a similar ovarian response in terms of the number of growing follicles and number of eggs retrieved. It is recommended that patients should be treated with the appropriate dose of corifollitropin alfa according to their body weight as a lower dose does not result in milder stimulation and a higher dose does not result in an improved ovarian response. Successful use of corifollitropin alfa requires assessment of patient suitability and dosing before the start of stimulation. After decades of daily dosing with FSH preparations, corifollitropin alfa allows a simpler IVF/intracytoplasmic sperm injection treatment regime with fewer injections.