Sanofi presents amended protocols in fitusiran clinical studies at EAHAD 2021

February 5, 2021
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Sanofi presents amended protocols in fitusiran clinical studies at EAHAD 2021

February 5, 2021

The amended protocol being implemented for all ongoing adult and adolescent fitusiran clinical studies was presented today at the 14th Annual Congress of the European Association for Haemophilia and Allied Disorders (EAHAD). Fitusiran is an investigational, subcutaneously administered small interference RNA therapy in development for the treatment of people with hemophilia A or B, with or without inhibitors.

Implementation of the amended protocol follows Sanofi’s voluntary pause in dosing and enrollment in the ongoing fitusiran clinical studies on October 30, 2020 to allow the investigation of reports of non-fatal thrombotic events in the trials. This assessment included analysis of reported thrombotic events, anti-thrombin levels, and other available clinical data.

Sanofi’s priority is the safety of patients. Amendments to the dose and dosing regimen, aimed at further enhancing the benefit-risk profile of fitusiran for patients, were highlighted in the oral presentation. Under the amended protocol, the dose for adults and adolescents will be reduced to 50 mg every other month (six times a year), with the potential to adjust the dose and/or dose frequency based on an individual patient’s anti-thrombin levels.

Sanofi has aligned with several health authorities, including the U.S Food and Drug Administration, on the amended protocol; dosing has resumed in certain countries following completion of local requirements. The company continues to engage with health authorities to resume fitusiran dosing worldwide as quickly as possible. Evaluation of dosing in the fitusiran pediatric study is ongoing and therefore, dosing in that study remains paused at this time.

Sanofi is committed to addressing the unmet needs of the global hemophilia community with a goal to break barriers that exist and help raise the standard of care. The company believes fitusiran may transform treatment for people with hemophilia A or B, with or without inhibitors as the only hemophilia prophylactic treatment with the potential for six subcutaneous injections per year.

Editor’s Note:

Fitusiran is an investigational, subcutaneously administered, small interference RNA therapeutic in development for the prophylaxis treatment of people with hemophilia A or B, with or without inhibitors. Fitusiran is designed to target antithrombin, a protein that inhibits blood clotting, with the goal of promoting sufficient thrombin generation to naturally rebalance hemostasis and prevent bleeds. Fitusiran utilizes Alnylam Pharmaceutical Inc.’s ESC-GalNAc conjugate technology, which enables subcutaneous dosing with increased potency and durability. Fitusiran is currently under clinical investigation and has not been evaluated by any regulatory authority.


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