Pfizer has received a setback from the US Food and Drug Administration, whose staff recommended against the approval of its tafamidis drug, used to treat familial amyloid polyneuropathy.
Despite already receiving approval in Europe under the name Vynqadel, the FDA recommended rejecting the drug, alleging that data did not prove its efficacy in treating the neurodegenerative disease.
Two reviewers said that clinical trial data suggested that tafamidis was most successful in treating patients in Portugal for unknown reasons, but that the present data did not prove the drug to help patients in other locations.
The clinical data could also have been skewed by people taking tafamidis appearing to have a milder version of the disease than those taking a placebo.
As a result, an FDA medical reviewer has recommended that the agency issue a complete response letter for tafamidis, as the drug failed to meet its primary goal of a measure of differences in muscle weakness and reflexes between patients treated with the drug and those who received placebo.
Familial amyloid polyneuropathy is a fatal condition that affects 10,000 people worldwide, with the majority of sufferers dying within 11 years of the onset of symptoms.
The only current treatment for the disease is a liver transplant, requiring the patient to take immunosuppressant drugs after surgery.