ATIR™, treated T cells for immune reconstitution

ATIR™ is used to treat patients requiring haploidentical stem cell transplantation, and who are unable to find a suitable matched donor. ATIR™ consists of donor immune cells (CD3+), from which the alloreactive T-cells, that would otherwise attack the patient’s body and cause graft vs host disease (GvHD), have been selectively eliminated by photodepletion. ATIR™ is infused into the patient about 4 weeks after the patient has undergone a standard stem cell transplantation, to boost immune reconstitution; the treatment obviates the need for immune suppressants post-transplantation. ATIR™ was found to be safe and effective. No patients developed grade III–IV acute GVHD and all had decreased rate of infections. Treatment resulted in an overall survival of 67% over the 5-year follow up period. In an additional study, chronic GvHD patients underwent leukapheresis and their cells were photodepleted and reinfused, inducing an increase in the number of Tregs in the peripheral blood and decreased signs of GvHD.