(Adds analyst estimates, background)
Sept 22 (Reuters) - The U.S. Food and Drug Administration has declined to approve Johnson & Johnson's rheumatoid arthritis drug sirukumab, saying additional clinical data is needed to further evaluate its safety, the company said on Friday.
The FDA's decision is in keeping with an advisory panel's recommendation in August that the FDA reject the drug. Panelists were concerned about an imbalance in the number of deaths in patients taking sirukumab compared with those taking a placebo.
The most common causes of death were major heart problems, infection and malignancies.
"We are disappointed by this development as we feel the data accumulated to date support the efficacy and safety of sirukumab," said Dr. Newman Yeilding, head of immunology at J&J's Janssen subsidiary. He added that the company is seeking to "gain a full understanding of FDA requirements for U.S. approval" and plans to have a follow-up discussion with the agency.
Sirukumab blocks a cytokine in the body known as interleukin 6 that can contribute to the inflammation associated with rheumatoid arthritis, an autoimmune disorder that affects more than 23 million people worldwide.
Other drugs in the same class include Roche Holding AG's Actemra and Sanofi SA and Regeneron Pharmaceuticals Inc's Kevzara.
Analysts on average had expected sirukumab, which would be known as Plivensia if ultimately approved, to generate annual global sales of $426 million by 2020.
J&J originally developed sirukumab with GlaxoSmithKline Plc but GSK recently said it would end the program and return all rights to J&J. GSK had rights to the drug in North, Central and South America.
In April the FDA declined to approve a rheumatoid arthritis drug made by Eli Lilly and Co and partner Incyte Corp, saying additional clinical data was needed to determine the most appropriate doses of the drug, baricitinib, and to further characterize safety concerns.
Baricitinib belongs to a class of drugs known as Jak inhibitors that include Pfizer Inc's Xeljanz and AbbVie Inc's Humira.
(Reporting by Toni Clarke in Washington; Editing by Meredith Mazzilli and James Dalgleish)