CRISPR Therapeutics and Vertex Score FDA RMAT Designation for Hemoglobinopathies Cell Therapy

The U.S. Food and Drug Administration granted Regenerative Medicine Advanced Therapy designation to CRISPR Therapeutics and Vertex Pharmaceuticals’ CTX001, their experimental stem cell therapy for the treatment of severe sickle cell disease and transfusion-dependent beta thalassemia.

Sickle cell disease (SCD) and transfusion-dependent beta thalassemia (TDT) are both genetic hemoglobinopathies that affect the ability of the blood to deliver oxygen to the cells throughout the body. In SCD, mutated hemoglobin causes the red blood cells to develop a sickle shape that impedes their flow through the body and causes anemia. TDT reduces the production of hemoglobin, the iron-containing protein in red blood that carries oxygen to cells.

CTX001 is an experimental ex vivo CRISPR gene-edited therapy that is being evaluated for patients suffering from SCD and TDT in which a patient’s hematopoietic stem cells are engineered to produce high levels of fetal hemoglobin (HbF) in red blood cells. HbF is a form of the oxygen-carrying hemoglobin that is naturally present at birth and is then replaced by the adult form of hemoglobin. The elevation of HbF by CTX001 has the potential to alleviate transfusion requirements for TDT patients and painful and debilitating sickle crises for SCD patients. CTX001 is the most advanced gene-editing approach in development for beta thalassemia and SCD.

CTX001 is being developed under a co-development and co-commercialization agreement between CRISPR Therapeutics and Vertex.

“RMAT designation is another important regulatory milestone for CTX001 and underscores the transformative potential of a CRISPR-based therapy for patients with severe hemoglobinopathies,” said Samarth Kulkarni, CEO of CRISPR Therapeutics. “We expect to share additional clinical data on CTX001 in medical and scientific forums this year as we continue to work closely with global regulatory agencies to expedite the clinical development of CTX001.”

RMAT designation is a program designed to expedite the drug development and review processes for promising pipeline products, including genetic therapies. The 21^st Century Cures Act established the program. A regenerative medicine therapy is eligible for RMAT designation if it is intended to treat, modify, reverse or cure a serious or life-threatening disease or condition, and preliminary clinical evidence indicates that the drug or therapy has the potential to address unmet medical needs for such disease or condition.

Similar to Breakthrough Therapy designation, RMAT designation provides the benefits of intensive FDA guidance on efficient drug development, including the ability for early interactions with FDA to discuss surrogate or intermediate endpoints, potential ways to support accelerated approval and satisfy post-approval requirements, potential priority review of the biologics license application and other opportunities to expedite development and review.

In addition to RMAT designation, CTX001 has received Orphan Drug designation from the FDA for TDT and from the European Commission for TDT and SCD. CTX001 also has Fast Track designation from the U.S. FDA for both TDT and SCD.

Photo: Samarth Kulkarni, CEO of CRISPR Therapeutics

Author: Rare Daily Staff