In documents posted ahead of an FDA advisory panel meeting, agency staff questioned whether clinical data on GlaxoSmithKline and Human Genome Sciences' experimental lupus drug Benlysta provided strong enough evidence of its benefit in relation to its known risks. The companies filed for approval of the drug in June for reducing disease activity in adults with systemic lupus erythematosus.

Staff noted that two large clinical trials demonstrated a statistically significant difference in the number of patients with lupus who responded to treatment with Benlysta, compared to placebo. However, the FDA said the results indicated "somewhat marginal efficacy," given that the drug's largest positive effect was on organ systems that are not life threatening.

FDA staff also noted that the drug's benefit appeared greater among patients from Latin America, compared with those from the US and Canada, while African-Americans patients fared worse. "The robustness and the clinical meaning of the efficacy findings warrant discussion," the staff said.

Risks associated with the use of Benlysta were also raised by the FDA, including the development of cancer, infections, and neuropsychiatric adverse events such as suicide. The agency staff said that although patients with lupus are known to have a higher risk of suicide, cases were higher for those who received Benlysta in clinical studies, compared to placebo.

Commenting on the documents, ISI Group analyst Mark Schoenebaum said there was "nothing surprising" in the FDA review other than the suicide issue. R.W. Baird analyst, Christopher Raymond, commented that "while the suicidality data point is news to us…this patient population is known to be at higher risk for suicide and the trials are 2:1 skewed toward Benlysta patients, making a strong argument for a chance outcome.

" Schoenebaum added that "we still think the panel is likely to vote for approval" when it meets on November 16, while RBC Capital Markets analyst, Michael Yee, said that he expects the FDA will approve the drug without requesting additional clinical trials.

A final decision by the US regulator is expected by December 9

 

• 
•