Sanofi has reported positive results from a pivotal Phase III trial of sutimlimab for the treatment of people with cold agglutinin disease (CAD), a serious, chronic, rare blood disorder.

The open-label, single-arm CARDINAL trial evaluated the safety and efficacy of the novel investigational C1s inhibitor and met its primary and secondary endpoints.

The results also demonstrated rapid inhibition of hemolysis and clinically significant improvements in anaemia and fatigue within one week of treatment.

Sutimlimab has been designed to selectively target and inhibit C1s in the classical complement pathway, a part of the immune system that activates the mechanism of hemolysis in CAD.

Sanofi intends to submit a Biologics License Application to the US Food and Drug Administration in the near future for sutimlimab, which has the potential to be the first approved therapy for CAD.

Sanofi Research and Development global head John Reed said: “CAD is a disease in which the immune system attacks red blood cells and causes a cascade of symptoms for patients. In our study, sutimlimab achieved clinically meaningful results by impacting the central mechanism of CAD, bringing about marked improvements in patients’ hemolysis, anaemia and fatigue.

“We are eager to share these results with regulatory authorities beginning with the US FDA in the near future in an effort to provide patients with a first-in-class targeted therapy that we believe has the potential to change the treatment paradigm for CAD.”

For the pivotal CARDINAL trial, 24 patients were enrolled and received at least one dose of the therapy.

Subjects were given a fixed weight-based dose of 6.5g or 7.5g through intravenous infusion on day one, day seven and then once every other week up to week 26.

All 22 patients who completed part A of the trial elected to continue the therapy in ongoing safety and durability of the response extension study, part B.

The study showed an overall mean increase in haemoglobin of 2.6 g/dL at the treatment assessment timepoint.

CAD is a chronic rare blood disease where a part of the body’s immune system mistakenly attacks a person’s own healthy red blood cells.

In July this year, Sanofi announced top-line data from three Phase III clinical trials performed to assess Zynquista (sotagliflozin) in adults with type 2 diabetes.