The Food and Drug Administration has denied Amgen’s application for a biosimilar of Roche’s breast cancer drug Herceptin.

The Thousand Oaks biopharma published a statement Friday on its website announcing that it had received a complete response letter from the FDA regarding its application for ABP 980, which it co-developed with Allergan in Dublin, Ireland. Complete response letters convey the FDA’s decision to reject a drug for market approval in its current form; the agency does not make the contents of the letters available to the public.

“We will work closely with the FDA to bring this important medicine to patients in the U.S.,” Amgen said in a statement. “We do not expect this to impact our U.S. launch plan.”

Amgen and Allergan filed their application with the FDA in August. The drug is one of a few Herceptin biosimilars that have been rejected in the U.S. but approved in Europe. The European Commission authorized ABP 980 for sale on May 16 under the trade name Kanjinti, according to the website of the European Medicines Agency.

Other drug makers that have had Herceptin copies turned down by the FDA include Pfizer Inc. and Mylan. But later Mylan and its India-based co-developer Biocon Ltd. won the agency’s approval for their biosimilar, Ogivri, in December, becoming the first company to do so.

A successful Herceptin biosimilar could generate significant revenue; sales of the drug were $2.7 billion in the U.S. in 2017, according to Roche.

Shares of Amgen (AMGN) rose $3.95, or 2.2 percent, on Friday to close at $183.57 on the Nasdaq.