FDA Clears First Treatment for Rare Anemia

Drugs works by interfering with the classical complement pathway.

FDA has approved Sanofi’s Enjaymo (sutimlimab-jome), the first and only approved treatment for cold agglutinin disease (CAD).

The medication decreases the need for red blood cell transfusion due to hemolysis in adults with CAD, Sanofi said in a news release.

“Until now, people living with cold agglutinin disease haven’t had an approved treatment option to manage the constant destruction of red blood cells. Without healthy, viable red blood cells, a chain reaction of debilitating signs and symptoms can be triggered, starting with severe anemia,” said Bill Sibold,
executive vice president, head of specialty care at Sanofi.

Enjaymo is expected to be available in the US in the coming weeks with a wholesale acquisition cost (WAC) of $1,800 per vial, Sanofi said.

However, actual costs to patients “are generally anticipated to be lower as the list price does not reflect insurance coverage, co-pay support, or financial assistance from patient support programs,” Sanofi added.

CAD, a chronic and rare blood disorder, impacts the lives of an estimated 5,000 people in the US.

It is caused by antibodies called cold agglutinins binding to the surface of red blood cells, which starts a process that causes the body’s immune system to mistakenly attack healthy red blood cells and cause their rupture (hemolysis). As red blood cells have the vital job of carrying oxygen throughout the body, patients with CAD may experience severe anemia, which can result in fatigue, weakness, shortness of breath, light-headedness, chest pain, irregular heartbeat, and other potential complications.

Enjaymo is a humanized monoclonal antibody that is designed to selectively target and inhibit C1s in the classical complement pathway, part of the innate immune system.

“By blocking C1s, Enjaymo inhibits the activation of the complement cascade in the immune system and inhibits C1-activated hemolysis in CAD to prevent the abnormal destruction of healthy red blood cells. Enjaymo does not inhibit the lectin and alternative pathways,” Sanofi said.

The approval of Enjaymo in the U.S. is based on positive results from the 26-week open label, single arm pivotal Phase 3 CARDINAL study in patients with CAD who have a recent history of blood transfusion.

In the study, Enjaymo met its primary efficacy endpoint, a composite endpoint defined as the proportion of patients who achieved normalization of hemoglobin (Hgb) level ≥12 g/dL or demonstrated an increase from baseline in Hgb level ≥2 g/dL at the treatment assessment time point and no blood transfusion from weeks 5 through 26 or medications prohibited per the protocol from weeks 5 through 26.

Secondary endpoints were also met, including improvements in hemoglobin and normalization of bilirubin.