Safety, Tolerability and Pharmacokinetics (PK) Study of Oxytocin (GR121619) Administered Via an Inhaled Route in Healthy Female Volunteers

Intramuscular (IM) oxytocin is the gold standard prophylactic therapy for post partum haemorrhage (PPH). However, in resource-poor settings within the developing world, the stability and therefore effectiveness of prophylactic IM oxytocin is diminished by a lack of appropriate refrigeration facilities and availability of trained health care professionals (HCPs) to administer IM injections. This study will be the first investigation of oxytocin in humans via the inhaled (IH) route and is designed to evaluate the safety and tolerability of inhaled oxytocin and the five non-pharmacologically active components in the placebo, and to establish the PK characteristics of up to four fixed escalating doses of inhaled oxytocin. In this single blind ascending dose-escalation study, the systemic exposure from up to four proposed escalating inhaled fixed-dose levels (50 micrograms \[mcg\], 200 mcg, 400 mcg and 600 mcg) will be compared with the systemic exposure following 10 international units (IU) of IM oxytocin in healthy premenopausal females.. A total of 15 subjects will be enrolled after screening sufficient number of healthy female subjects and the subjects will be assigned to one of the two treatment sequences. The total duration of this study is approximately 20 weeks.