Introduction

Premature Ejaculation (PE) is associated with rapid ejaculation, inability to delay ejaculation and distress. There are no approved pharmacological treatments in US. The objective was to test the efficacy and safety of IX-01, an orally administered selective oxytocin receptor (OTR) antagonist with potential to treat PE.

Methods

A double-blind, placebo-controlled trial (NCT02232425) was performed in US and Australia. Eligibility criteria included lifelong PE, ≥4 intercourse attempts during a 4 week run-in, with intravaginal ejaculatory latency time (IELT) ≤1 minute measured by stopwatch on ≥75% occasions and none > 2 minutes. Men were randomized (2:1) to receive IX-01 or placebo taken 1-6 hours before intercourse during 8 weeks treatment. The starting dose was 400 mg and could be increased to 800 mg or equivalent placebo. Efficacy was assessed by IELT, Clinical Global Impression of Change (CGIC), and Premature Ejaculation Profile (PEP). Safety assessments included adverse events (AEs), vital signs, laboratory tests, electrocardiograms, and depression scales.

Results

Eighty-six men (mean age 43 years) received ≥1 dose of study drug. Men took a mean of 14.6 (range 1-59) and 13.0 (range 1-51) doses of IX-01 and placebo respectively. Fifty (89.3%) men took the maximum 800 mg dose of IX-01 at least once during the study. The main efficacy results are depicted in Table 1. IX-01 showed clinically and statistically significant improvements in IELT and patient reported outcomes compared to placebo. A summary of the AE&[prime]s is presented in Table 2. The AE profile of IX-01 was similar to placebo. No other safety signals were detected.

Conclusions

This is the first study to demonstrate the efficacy of an OTR antagonist to treat PE. IX-01 was well tolerated and prolonged IELT, and improved ejaculation control and diminished distress in men with lifelong PE.

Funding

Ixchelsis Ltd.