Fitusiran “tremendous leap forward” for hemophilia treatment

Reuters Health - 20/12/2021 - Fitusiran, an experimental hemophilia therapy administered monthly via subcutaneous injection, greatly reduced bleeding in patients with hemophilia A or B in a phase-3 trial reported at the American Society of Hematology annual meeting.

"I think this is a tremendous leap forward in therapy that we can bring to this community," Dr. Steven Pipe of the University of Michigan in Ann Arbor said during a press briefing.

"Based on some of the dosing schedules that are currently being evaluated with fitusiran, it's possible to achieve effective prophylaxis with as little as six subcutaneous injections over the course of a year," he said.

Fitusiran is a small interfering RNA therapeutic that targets antithrombin to "enhance thrombin generation potential and rebalance hemostasis" in people with hemophilia, irrespective of inhibitor status, the researchers explain in their late-breaking conference abstract.

The ATLAS-A/B study patients with hemophilia A or B without inhibitors who were being managed with on-demand replacement therapy; 79 were randomly allocated to 80 mg subcutaneous, once-monthly fitusiran prophylaxis and 40 to continue on-demand treatment.

The median annualized bleeding rate in the on-demand treatment group was 21.8 bleeds per year, compared with zero in the fitusiran group - an estimated reduction in annual bleeding rate of 89.9% (P<0.0001), Dr. Pipe reported.

Annual joint bleeding rates decreased similarly by 90.3% with fitusiran, he noted.

"The reduction in bleeding was associated with a meaningful improvement in quality of life," Dr. Pipe told the briefing.

"The convenience of this drug, and the high proportion of people who have zero or only a few bleeds, suggests we can really make a difference in the quality of life for people with severe hemophilia," study co-author Dr. Alok Srivastava of Christian Medical College in Vellore, India, said in a news release.

"With a monthly medication, hemophilia becomes easier to treat. You can reduce the number of times you have to receive intravenous injections, and the steady blood level of the drug means you can feel safer being more active and perhaps a little less fearful of bleeding in your daily activities," Dr. Srivastava added.

The most common adverse events with fitusiran included the common cold, upper-respiratory-tract infection, abdominal pain, joint pain, asthma, stomach inflammation, headache, and elevated liver enzymes.

Two patients discontinued fitusiran because of adverse events; one due to elevated liver enzymes, and one due to cholecystitis. There were five serious adverse events in the fitusiran group, and nine in the on-demand treatment group. There were no clotting-related or fatal adverse events.

The reported treatment-emergent adverse events were "generally consistent with previously identified risks of fitusiran," Dr. Pipe said.

The trial was funded by Sanofi, which is developing fitusiran. Several authors have disclosed financial relationships with the company.

SOURCE: https://bit.ly/3ge0KON American Society of Hematology 2021 Annual Meeting, held December 11-14, 2021.

By Megan Brooks



Posted on 20 December 202112 January 2022