Cetrorelix in an oral contraceptive-pretreated stimulation cycle compared with buserelin in IVF/ICSI patients treated with r-hFSH: a randomized, multicentre, phase IIIb study

Abstract

The aim of this study was to assess the non-inferiority of an oral contraceptive (OC)-pretreated cetrorelix regimen and a buserelin regimen in IVF/ICSI patients treated with r-hFSH in terms of total number of oocytes retrieved. Multicentre, randomized study. One hundred and eighty two patients were randomized to receive cetrorelix with OC pretreatment (n = 91) or to receive buserelin (n = 91). The cetrorelix group started with daily OCs on cycle day 5 and continued for 21-28 days. Cetrorelix (0.25 mg) was given daily from stimulation day 6 up to and including the day of r-hCG administration. The buserelin group started with buserelin (500 microg/day) for at least 10 days until down-regulation was achieved, after which the dose was reduced to daily 200 microg up to and including the day of r-hCG administration. r-hFSH was started in both groups on a Friday, in the cetrorelix group 5 days after the last OC pill intake. Both regimens were followed by a standard IVF or ICSI procedure. The primary efficacy endpoint was the number of oocytes retrieved per patient. Number of oocytes, cancellation rates, r-hFSH requirements, number of oocyte retrievals during the weekend or public holiday and number of pregnancies were similar in both groups. Both treatment regimens were well tolerated. Cetrorelix pretreated with OCs resulted in similar number of oocytes retrieved compared with a long buserelin protocol. Both regimens were well tolerated and allowed scheduling of the oocyte retrieval, with only small number of retrievals falling on a weekend or public holiday.