Recombinant follicle-stimulating hormone (follitropin alfa) versus purified urinary follicle-stimulating hormone in a low-dose step-up regimen to induce ovulation in Japanese women with anti-estrogen-ineffective oligo- or anovulatory infertility: results of a single-blind Phase III study.

PURPOSE

We aimed to compare the efficacy and safety of recombinant human follicle-stimulating hormone (follitropin alfa) and purified urinary human follicle-stimulating hormone (urofollitropin) for ovulation induction in Japanese women with anovulatory infertility;also to verify the noninferiority (in terms of ovulation rate) of follitropin alfa versus urofollitropin.

METHODS

In a Phase III, multicenter, single-blind, parallel-group study, we enrolled 265 Japanese women aged 20-39 years. The patients were menstruating without apparent ovulation or were amenorrheic (with a positive progestin challenge test), and had failed to conceive with anti-estrogen ovulation-induction therapy. The patients underwent a low-dose step-up regimen using follitropin alfa or urofollitropin with a starting dose of 75 IU. The primary endpoint was the proportion of patients who ovulated (mid-luteal serum progesterone ≥5 ng/mL and/or confirmed clinical pregnancy). Secondary endpoints included the proportion of patients with a dominant follicle (≥18 mm) and the duration of stimulation.

RESULTS

Ovulation occurred in 79.1% and 82.6% of the patients who received follitropin alfa and urofollitropin, respectively, in the full-analysis set ( = 261), and in 79.2% and 82.5% of the per-protocol set ( = 251). The predefined noninferiority criteria for the primary endpoint were achieved. No significant differences were observed in any secondary endpoint. Treatment-emergent adverse events were reported by a similar proportion of patients in each group (follitropin alfa, 53.5%; urofollitropin, 50.0%).

CONCLUSIONS

No significant difference in the primary efficacy endpoint (rate of ovulation) was observed between follitropin alfa and purified urofollitropin in women with anovulatory infertility who were menstruating or had progestin-positive amenorrhea. The use of treatment holidays in this study prevents comparison of the data with previous trials that utilized consecutive daily doses.