An injection-lite approach to ovarian stimulation in poor responder patients using corifollitropin alfa and nasal GnRH agonist

OBJECTIVE: Can the unique pharmacokinetic and pharmacodynamic profiles of corifollitropin alfa (CFA) in combination with an intra-nasal GnRH agonist (CFA flare) provide adequate ovarian stimulation for poor-responder patients while minimising the burden of injections? METHODS: Twenty women aged between 31 and 41 years of age who were identified as potential poor responders to ovarian stimulation according to the POSEIDON criteria and who were attending the Fertility and Research Centre, Royal Hospital for Women and City Fertility, Sydney for IVF treatment were randomised to receive either the flare or the antagonist cycle. Serum FSH, LH, and E2 concentrations were measured daily for 5 days post-initiation of CFA during the early follicular phase. RESULTS: The number of injections given to women in the CFA flare arm (4) was significantly less than those in the CFA antagonist arm (11), (p = 0.001). Two days after the initiation of CFA, serum FSH concentrations were 27 versus 11 IU/L (flare versus antagonist) (p = 0.022), and mean serum E2 concentrations were 349 versus 157 pmol/L (p = 0.039), and on day 7, were 3000 versus 1850 pmol/L. The CFA flare stimulation protocol resulted in higher concentrations of FSH in the early period of follicular stimulation. There was an equivalent rise in serum E2 in both groups. The CFA flare protocol was non-inferior to the CFA antagonist protocol and may have been less burdensome to patients as fewer injections were needed. CONCLUSION: The CFA flare protocol is a novel alternative to conventional ovarian stimulation regimens that are used for 'poor responder' patients. It significantly reduces the patient burden, with less injections of FSH and no injections of GnRH antagonist. The ovarian response is similar to that achieved with a conventional GnRH antagonist cycle, but this requires further evaluation in a larger study.