Trial of Fitusiran for Haemophilia Suspended After Patient Death
WASHINGTON, DC -- November 9, 2017 -- Alnylam Pharmaceuticals, Inc., suspended a phase 2 trial of its investigational RNA inhibitor fitusiran for patients with haemophilia after a patient with haemophilia A experienced a fatal thrombotic event while enrolled in the open-label extension study, which was assessing fitusiran in patients with haemophilia A or B with or without inhibitors.
The suspension also affects the phase 3 ATLAS study, which was recently initiated but had not yet started dosing.
The drug’s manufacturer did not indicate whether the death was directly related to fitusiran use.
Approximately 9 days prior to hospital admission, the patient developed exercise-induced right hip pain that was treated with a total of 3 doses of factor VIII (FVIII) concentrate (31-46 IU/kg) on 3 separate days. Over a 14-day hospitalisation, the patient’s medical condition worsened despite receiving FVIII, and the patient died from subsequent cerebral oedema.
The investigators reported the initial diagnosis of subarachnoid haemorrhage as unrelated to fitusiran treatment, but further analysis of computed tomography scans confirmed that the triggering event was a cerebral venous sinus thrombosis.
The company is conducting a safety review of the trial with the US Food and Drug Administration (FDA) to investigate a possible connection between the drug and serious thrombotic events and to develop a risk-mitigation plan.
SOURCE: American Society of Hematology