Allergan and Gedeon Richter are gearing up to file ulipristal acetate in the US in the second half of this year, in the hope of securing approval for the first oral treatment option for women suffering from uterine fibroids in the country.

The Irish and Hungarian drugmakers have unveiled data from the second of two pivotal Phase III clinical trials, the 432-patient Venus II study, which showed that the drug was significantly superior to placebo on all primary and secondary endpoints.

The co-primary efficacy endpoints were percentage of patients with absence of uterine bleeding and time to absence of uterine bleeding on treatment during Treatment Course One (12-week duration). Significantly more patients in the 10mg group (54.8 percent) and the 5mg group (42.0 percent) achieved absence of bleeding compared to placebo (0 percent).

Also, the improvement from baseline in the UFS-QOL revised activities subscale, which assesses the impact on the well-being of women with uterine fibroids, was significantly greater in the 10mg group (56.7 percent) and the 5mg group (48.3 percent) compared to placebo (13.0 percent).

The most common side effects (≥5 percent) on ulipristal acetate treatment were hot flush, headache, fatigue, and nausea in the combined period of Treatment Course One and the first off-treatment interval, the firms noted.

"We are confident that the results of our Phase III trials for ulipristal acetate may potentially offer the first and only oral treatment option for women suffering from uterine fibroids in the US," said David Nicholson, Chief Research and Development Officer, Allergan.

Uterine fibroids are responsible for over 350,000 hospitalisations in the US and cost the economy over $34 billion each year.

Outside of the US, ulipristal acetate is approved for the pre-operative and intermittent treatment of moderate to severe symptoms of uterine fibroids in adult women of reproductive age in Europe, where it is marketed as Esmya, and Canada, under the brand name Fibristal.