Oct 4 (Reuters) - Biogen Idec's hot-selling new multiple sclerosis drug Tecfidera remained effective for patients taking the medicine for at least four years with no new safety problems, according to interim data from a long-term study.
Tecfidera, which analysts expect to eventually dominate the MS market, had sales of $192 million in its first quarter on the market - nearly triple average Wall Street expectations.
The Endorse extension study followed patients who had taken part in two pivotal Phase III trials that led to the U.S. approval of Tecfidera.
The drug maintained its ability to reduce disease activity as measured by relapses and disease progression in patients treated for four years, the interim data showed.
In addition, there were no new or worsening safety problems observed even in patients taking Tecfidera for up to six and a half years, according to the interim analysis presented on Friday at a major multiple sclerosis medical meeting in Copenhagen.
Patients in the extension study also experienced a low frequency of new MS brain lesions similar to what had been observed after two years.
"These interim Endorse findings reaffirm, over the longer term, the outcomes we have previously observed with Tecfidera and provide important information for physicians and patients," Dr. Ralf Gold, chairman of the department of neurology at St. Josef Hospital in Bochum, Germany, said in a statement.
There was no increased risk of serious infections or cancers and no overall increased risk of kidney dysfunction or liver problems seen in the long-term study, Biogen said.
Patients in the earlier two-year Phase III studies who had been in the control groups that received either a placebo or Copaxone - the current MS market leader from Teva Pharmaceutical Industries - were given Tecfidera in the Enforce extension trial. They had similar favorable clinical responses as those who had received the Biogen drug in the earlier trials, the company said.
In those studies, Tecfidera led to a 54 percent reduction in the risk of MS relapse compared with placebo.
Researchers will continue to follow the 1,738 patients with relapsing-remitting multiple sclerosis (RRMS) in the Endorse trial. They are receiving 240 milligrams of Tecfidera either two or three times a day.
About two million people suffer from MS worldwide. RRMS is the most common form of the disease, characterized by episodes of worsening neurologic function followed by periods of remission involving partial or complete recovery, according to the Multiple Sclerosis International Federation.