FDA Rejects Application for Chronic Fatigue Drug Ampligen (Rintatolimod)
Drug’s developer plans to appeal the decision (Feb. 4)
The FDA has declined to approve the new drug application (NDA) for Ampligen (rintatolimod injection; Hemispherx Biopharma) for the treatment of chronic fatigue syndrome (CFS). The agency said that the drug’s developer should conduct at least one additional clinical trial, complete various nonclinical studies, and perform a number of data analyses.
In its complete response letter, the FDA set forth the reasons for this action and provided recommendations to address some of the outstanding issues. The agency stated that the submitted data do not provide substantial evidence of the efficacy of Ampligen for the treatment of CFS. In addition, the agency said that the data do not provide sufficient information to determine whether the product is safe for use in CFS because of the limited size of the safety database and because of multiple discrepancies and gaps in the submitted data. The agency voted 8 to 5 against approving Ampligen for the treatment of patients with CFS.
On the other hand, the drug’s developer, Hemispherx Biopharma, believes that Ampligen met the primary efficacy endpoints and showed a statistically significant improvement versus placebo (i.e., with a P value of 0.05 or less) in the two pivotal clinical studies that formed the basis of the drug’s approval application. The FDA and Hemispherx agree that in clinical study AMP-502, the primary endpoint was met (P = 0.02). In clinical study AMP-516, however, the FDA’s analysis resulted in a P value of 0.10, whereas Hemispherx calculated a P value of less than 0.05.
Hemipsherx originally submitted an NDA for the use of Ampligen to treat CFS in 2007. In 2009, the FDA’s review division asked the company to conduct at least one additional controlled clinical study showing a convincing effect in the CFS population, but no new trials were conducted.
Hemispherx plans to submit a formal appeal to the Office of New Drugs in the FDA’s Center for Drug Evaluation and Research regarding the agency’s recent decision.