The US Food and Drug Administration (FDA) has granted fast-track designation to Pfizer’s investigational candidate, tafamidis, for the treatment of patients with transthyretin cardiomyopathy (TTR-CM).
TTR-CM is caused due to destabilisation of a transport protein called transthyretin, which consists of four identical sub units (tetramer), and tafamidis is designed as a specific TTR stabiliser.
In the case of TTR-CM, heart failure is said to occur when unstable tetramers detach and the misfolded proteins form a cluster of amyloid fibrils that is deposited in the heart.
Tafamidis was initially approved in the European Union (EU) in 2011 to delay peripheral neurologic impairment in adults suffering from transthyretin familial amyloid polyneuropathy (TTR-FAP) associated with early stage symptomatic polyneuropathy.
Under the trade name Vyndaqel, tafamidis is currently available for TTR-FAP indication in 40 countries such as Brazil, Mexico, Argentina, Israel, Russia and South Korea.
Pfizer global product development rare disease senior vice-president and chief development officer Brenda Cooperstone said: “The fast-track designation for tafamidis is an important milestone, as there are no currently approved treatments for TTR-CM in the US.
“We look forward to working closely with the FDA to evaluate this medicine as a potential new treatment option for patients.”
Tafamidis is being investigated in a Phase III transthyretin amyloid cardiomyopathy tafamidis (ATTR-ACT) clinical trial for its ability to minimise mortality and cardiovascular-related hospitalisations.
The double-blind, placebo-controlled trial includes patients with wild-type TTR-CM, as well as variant transthyretin familial amyloid cardiomyopathy (TTR-FAC) patients.
The trial has concluded enrolment and is expected to be completed in the first half of next year.