ZURICH (Reuters) – Swiss-listed drugmaker ObsEva said on Thursday it is abandoning the current program for its drug prospect nolasiban after the agent aimed at boosting pregnancy following in-vitro fertilization (IVF) failed a late-stage study in Europe.

Nolasiban did not meet the primary endpoint of an increase in ongoing pregnancy at 10 weeks, with 39.1% of women who got the placebo experiencing an ongoing pregnancy, compared with 40.5% of women who got nolasiban, the company said in a statement.

This proposed use of nolasiban, an oral oxytocin receptor antagonist licensed from Merck KGaA to help women getting IVF therapy, had been a central part of ObsEva’s plans. The trial failure leaves the company with drug candidates for endometriosis and potentially dangerous pre-term labor.

“We are extremely disappointed with these unexpected results, not in the least for the millions of women hoping to have a baby through IVF,” said Ernest Loumaye, a gynaecologist and former Serono drug developer who founded ObsEva.

“We have decided to discontinue the current nolasiban IVF program and will explore potential repositioning of the product candidate.”

ObsEva added a share listing in Switzerland last year, in addition to trading on the Nasdaq in the United States starting in 2017. The shares are down 36% this year.

(Reporting by John Miller; Editing by Michael Shields)