FDA Turns Down Cladribine for MS

Review

The FDA said it won’t approve the oral multiple sclerosis drug cladribine without more data on its safety and benefit-risk balance.

Merck KGaA, the drug’s German manufacturer, said it has received a complete response letter from the FDA indicating that the company would have to provide additional analyses of its clinical trials data or conduct new studies to satisfy its concerns.

However, the company said it was encouraged that the letter confirmed that the existing trial data were adequate to support the drug’s efficacy in reducing MS exacerbations and progression.

Cladribine is currently marketed as a chemotherapy drug for certain leukemias and lymphomas. A series of studies has shown that it inhibits activity and proliferation of lymphocytes involved in MS, prompting Merck KGaA to seek approval for cladribine as a treatment for the autoimmune disease.