Study finds increased risk of mortality in people with cold agglutinin disease in five years after diagnosis

Bioverativ Inc., a Sanofi company dedicated to transforming the lives of people with rare blood disorders, today announced results from a new, population-based retrospective study that found a greater than twofold increased risk of mortality in people with cold agglutinin disease (CAD) within the first five years after diagnosis. The study, which is the first to compare overall survival among people with CAD with that of the general population, also showed that the increased risk of mortality and life-threatening thromboembolic events (TEs) such as stroke and heart attack was evident starting in the first year after diagnosis. These data were presented at the 23^rd Annual Congress of the European Hematology Association (EHA).

"The results of our survival analysis contribute to the growing body of evidence that indicate that CAD is a more severe disease than previously thought," said Sigbjørn Berentsen, MD, PhD, Consultant Hematologist, Department of Research and Innovation, Haugesund Hospital in Norway. "The increased mortality from CAD appears to start at disease onset, and the possible effect of earlier treatment in reducing mortality and complications should be explored in future studies."

CAD is a rare, chronic, and severe blood disease that results in the constant and premature destruction of red blood cells (hemolysis) by the body's immune system. People with CAD suffer from chronic hemolytic anemia, which is associated with debilitating fatigue, poor quality of life, and life-threatening TEs. There are currently no approved treatments for the disease.

In the survival study, researchers conducted a population-based analysis to identify and characterize CAD patients. Using data from the Danish National Patient Registry, 72 patients with a diagnosis of CAD were compared to a cohort of 720 people without CAD matched for age, gender, and region of residence. The study found that the risk of death was 2.27 times higher in the CAD cohort than in the general population in the first five years from diagnosis. Further, the probability of survival was only 61% among CAD patients five years after diagnosis versus 82% for individuals in the general population cohort.

The study also identified an increased incidence of TEs among CAD patients. This finding is consistent with the largest retrospective study of CAD patients, which was recently presented at the American Society of Hematology annual meeting and found a 55% overall increased rate of TEs such as heart attack and stroke in CAD patients versus matched controls (31% vs. 20%), as well as a statistically significant higher frequency of multiple TEs.

"These data show that greater understanding is required about the risks associated with cold agglutinin disease, and they reinforce the pressing need for an approved and targeted treatment for this life-threatening condition," said Jaime Morales, MD, FAAP, Executive Director, Medical, Bioverativ. "That is why we are conducting Phase 3 trials of sutimlimab, a novel treatment that has been designed to directly and specifically target CAD."

Sutimlimab (formerly BIVV009) is an investigational monoclonal antibody designed to inhibit C1s in the classical complement pathway, a part of the immune system that is responsible for activating hemolysis in people with CAD. Sutimlimab has been awarded Breakthrough Therapy Designation by the U.S. Food and Drug Administration, and Phase 3 studies are ongoing to determine the safety and efficacy of BIVV009 in primary CAD patients. For more information about the sutimlimab Phase 3 studies, visit clinicaltrials.gov (study numbers: NCT03347396 and NCT03347422).