U.S. regulators have not approved Novartis's Prexige painkiller, the Swiss drugmaker said on Thursday, in an expected move after Australia withdrew the drug due to concerns over liver side effects.
"Novartis has received a 'not approvable' letter from the U.S. Food and Drug Administration," the company said.
"Novartis (will) continue discussions with (the) FDA and believes Prexige a valuable treatment option for appropriate patients with osteoarthritic pain," it said.
Novartis Chief Executive Daniel Vasella said in September he did not expect Prexige to gain U.S. approval.
Analysts had also doubted the drug, a so-called COX-2 inhibitor, would get to markets in the United States, after Australian regulators last month withdrew the product over concerns of serious liver side effects.
Australia's drugs watchdog had received eight reports of serious liver side effects associated with the use of the drug, including two deaths and two liver transplants.
Prexige, which had modest sales of $52 million in the first half of the year, is approved in more than 50 countries, and is currently being rolled out in Europe.
Last month, Novartis informed doctors in Europe of new restrictions on prescribing Prexige, saying it should not be used in patients with current liver disease or those at risk because of their histories or other medicines.
COX-2s have been under a cloud since the withdrawal of Merck & Co.'s Vioxx in 2004 after studies found it raised heart attack risks.