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T cells
The US Food and Drug Administration (FDA) has granted Regenerative Medicine Advanced Therapy (RMAT) designation to ATIR101™, which is intended to be used as an adjunct to haploidentical hematopoietic stem cell transplant (HSCT).
ATIR101 is a personalized T-cell immunotherapy—a donor lymphocyte preparation selectively depleted of host-alloreactive T cells through the use of photo-dynamic therapy.
Recipient-reactive T cells from the donor are activated in a unidirectional mixed-lymphocyte reaction. The cells are then treated with TH9402 (a rhodamide-like dye), which is selectively retained in activated T cells.
Subsequent light exposure eliminates the activated recipient-reactive T cells but preserves the other T cells.
The final product is infused after CD34-selected haploidentical HSCT with the goal of preventing infectious complications, graft-versus-host disease (GVHD), and relapse.
About RMAT designation
The RMAT pathway is analogous to the breakthrough therapy designation designed for traditional drug candidates and medical devices. RMAT designation was specifically created by the US Congress in 2016 in the hopes of getting new cell therapies and advanced medicinal products to patients earlier.
Just like breakthrough designation, RMAT designation allows companies developing regenerative medicine therapies to interact with the FDA more frequently in the clinical testing process. In addition, RMAT-designated products may be eligible for priority review and accelerated approval.
A regenerative medicine is eligible for RMAT designation if it is intended to treat, modify, reverse, or cure a serious or life-threatening disease or condition, and if preliminary clinical evidence indicates the treatment has the potential to address unmet medical needs for such a disease or condition.
“To receive the RMAT designation from the FDA is an important milestone for Kiadis Pharma and a recognition by the FDA of the significant potential for ATIR101 to help patients receive safer and more effective bone marrow transplantations,” said Arthur Lahr, CEO of Kiadis Pharma, the company developing ATIR101.
“We are now going to work even closer with the FDA to agree a path to make this cell therapy treatment available for patients in the US as soon as possible. In Europe, ATIR101 was filed for registration in April 2017, and we continue to prepare the company for the potential European launch in 2019.”
ATIR101 trials
Results of a phase 2 trial of ATIR101 were presented at the 42nd Annual Meeting of the European Society of Blood and Marrow Transplantation in 2016.
Patients who received ATIR101 after haploidentical HSCT had significant improvements in transplant-related mortality and overall survival when compared to historical controls who received a T-cell-depleted haploidentical HSCT without ATIR101.
None of the patients who received ATIR101 developed grade 3-4 GVHD, but a few patients did develop grade 2 GVHD.
A phase 3 trial of ATIR101 is now underway. The trial is expected to enroll 200 patients with acute myeloid leukemia, acute lymphoblastic leukemia, or myelodysplastic syndrome.
The patients will receive a haploidentical HSCT with either a T-cell-depleted graft and adjunctive treatment with ATIR101 or a T-cell-replete graft and post-transplant cyclophosphamide.
