Novartis Discontinues Phase II CIRRUS-1 Study of CD40 Monoclonal Antibody Iscalimab (CFZ533) for Prevention of Kidney Transplant Rejection

On the 3rd, Novartis announced the termination of the CIRRUS-1 study of CFZ533 (iscalimab) for the prevention of organ transplant rejection in kidney transplant recipients. Novartis made this decision following an interim analysis of the study.

Interim analysis results showed that in kidney transplant recipients, CFZ533 (iscalimab) demonstrated inferior efficacy to tacrolimus in preventing organ transplant rejection when used in combination with other immunosuppressants (induction therapy, mycophenolate, and corticosteroids). Novartis is currently further evaluating the trial data from the CIRRUS-1 study and will discuss the findings in detail with the Scientific Committee upon completion.

Iscalimab was engineered from lucatumumab by introducing an N297A mutation in the Fc region, thereby abolishing its ability to bind Fcγ receptors and eliminating Fc-mediated effector functions. Iscalimab does not deplete B cells but inhibits the activation of the CD40 signaling pathway.

Clinical trials of CFZ533 for liver transplant recipients and indications such as hidradenitis suppurativa and Sjögren's syndrome are still ongoing.