Cellectis’ CAR-T Trial for Multiple Myeloma on Clinical Hold

 

Cellectis, based in Paris and New York, announced that the U.S. Food and Drug Administration (FDA) has placed a clinical hold on its MELANI-01 trial. MELANI-01 is a Phase I open-label first-in-human dose escalation study of UCARTCS1A for relapsed or refractory multiple myeloma (MM).

UCARETCS1A is an allogeneic, off-the-shelf, gene-edited T-cell therapy designed to treat CS1/SLAMF7-expressing hematologic cancers. CS1 (SLAMF7) is highly expressed on multiple myeloma cancer cells.

The hold was apparently based on a safety issue in one patient enrolled at the study at dose level two (DL2). The patient had r/r multiple myeloma. The patient had been treated previously with several lines of therapy, including autologous CAR T-cells, without success. During this trial, the patient had a fatal treatment-emergent cardiac arrest. The company is continuing to evaluate the clinical data and other details related to the causes of the death.

Prior to the clinical hold, Cellectis had planned to expand enrollment at DL1, which the company believes may be the appropriate dose in the expansion cohort and potentially be the recommended dose for a Phase II trial.

“We share the FDA’s commitment to patient safety and are working collaboratively with the agency and the investigators to resolve this clinical hold,” said Carrie Brownstein, chief medical officer of Cellectis. “The safety of patients enrolled in our clinical trials is our utmost priority and we at Cellectis remain committed to safely resuming the clinical development of UCART product candidate targeting CS1 for patients with multiple myeloma and unmet medical need.”

Cellectis is continuing patient enrollment in two other ongoing Phase I dose escalation trials. AMELI-01 is studying UCART123 in relapsed and refractory acute myeloid leukemia and BALLI-01 is investigating UCART22 in relapsed and refractory B-cell acute lymphoblastic leukemia.

It was also announced today that Andre Choulika, chairman and chief executive officer of Cellectis, is retiring from the board of directors of Calyxt, effective immediately. He indicated he plans to focus all his energy on Cellectis’ development activities.

“Back in March 2010, Cellectis started Cellectis Plant Sciences, now Calyxt,” said Choulika. “I’m very proud of this amazing journey, which was brought to fruition by using our leading-edge TALEN technology to bring healthier, more sustainable products to market. Tens of thousands of acres have been planted with Calyxt seeds across multiple states, and this is just the beginning. Calyxt is at a pivotal stage in its growth, and at a point of maturity that requires deep commitment to reach the next development steps.”

He went on to say, “At the same time, Cellectis is at a critical turning point with very promising programs in development. We have ongoing clinical trials and more product candidates in preclinical development. It is for this reason that I have decided to focus 100% of my energy on Cellectis moving forward. My focus cannot be divided. I am confident that with Yves Ribeill’s guidance, in close collaboration with Jim Blome, Calyxt’s CEO, the company will continue to provide plant-based solutions to the world.”

Cellectis’ TALEN is a gene editing technology. Along with PulseAgile, its electroporation system, the company is working to develop off-the-shelf and ready-to-use gene-edited CAR-T products for cancer. To date, CAR-T therapies are uniquely engineered for individual patients, which is time-consuming and expensive. There are currently two CAR-T products approved, Novartis’ Kymriah (tisagenlecleucel) and Gilead Sciences’ Yescarta (axicabtagene ciloleucel).