FDA pushes back PDUFA date on Allergan’s uterine fibroid drug

When it filed for regulatory approval last October, Allergan expected the PDUFA date to fall in the first half of the year. (CQ-Roll Call/Getty Images)

The FDA has extended the PDUFA date for Allergan’s uterine fibroid candidate, ulipristal acetate, to August. When Allergan submitted the drug for consideration last year, the company expected the action date to fall in the first half of 2018.

The agency pushed the date “to provide time for a full review of the file,” Allergan said in a statement.

Ulipristal acetate was originally developed and marketed as Esyma for certain patients with uterine fibroids. It hit the European market in 2012. But after four reports of liver injury serious enough to require transplant emerged, the EMA's Pharmacovigilance Risk Assessment Committee (PRAC) the drug is now reviewing the drug.

"As the evaluation by PRAC continues, Allergan has provided the FDA updates regarding the ongoing drug safety evaluation and provided an update in January 2018. As a result, the FDA required more time and extended the NDA review," Allergan said in an email.

Ulipristal acetate works as a selective progesterone receptor modulator, acting directly on the progesterone receptors in three target tissues: the uterine lining, uterine fibroids and the pituitary gland.

The drug aced a phase 3 trial in uterine fibroids in May 2016, and in January last year, posted positive results from a second phase 3 trial, prompting the company to file for FDA approval in the second half of 2017.

The first trial, dubbed Venus I, involved 157 patients, with 101 randomized to receive 10 mg or 5 mg of ulipristal acetate and 56 to receive placebo. The trial met its primary endpoints, beating placebo in reducing bleeding and improving quality of life. It met its secondary endpoints, as well as its coprimary endpoints—the percentage of patients with absence of uterine bleeding and time to absence of uterine bleeding—with significantly more patients in the 10 mg group (58.3%) and the 5 mg group (47.2%) achieving an absence of bleeding compared to placebo (1.8%).

Hungarian pharma Gedeon Richter sells Esyma in Europe and Canada. But while the active ingredient of ulipristal acetate is available stateside as the contraceptive pill Ella, Allergan hasn't had much luck getting it off the ground for uterine fibroids in the U.S.

When Allergan unveiled the Venus I data, EP Vantage analysts noted that Allergan—then Watson—had tried to get Esyma past the FDA in 2013, but a phase 3 study in anemia associated with fibroids, announced in 2012, was quietly withdrawn before it started enrolling, the company said.

Editors note: This story has been edited to include comments from Allergan.