The US Food and Drug Administration (FDA) has placed a clinical hold on Arcellx’s IMMagine-1 Phase II study of CART-ddBCMA, a BCMA-specific CAR-modified T-Cell therapy, for the treatment of relapsed or refractory multiple myeloma (RRMM).

The clinical hold is placed following the recent death of a patient.

IMMagine-1, the multicentre, open-label study assessed the safety of its investigational new drug, CART-ddBCMA in patients with RRMM.

Evaluating the overall response rate over 24 months is the primary objective of this study.

The secondary endpoints include overall survival during the same period, duration of response, and depth of disease response.

Arcellx chairman and CEO Rami Elghandour said: “In coordination with our investigators, data safety monitoring board (DSMB), and our partners at Kite Pharma, we are working with the FDA to address the clinical hold.

“The expansion of bridging therapy regimens is consistent with what's currently available in clinical practice and is in the best interest of patients.

“Additionally, we continue to evaluate other potential improvements to the study.”

Arcellx will continue to dose patients who have undergone lymphodepletion, as per the FDA’s approval.

Elghandour added: “The manufacturing success rate remains 100% while ramping Lonza, our cell therapy manufacturer, to full scale. Fourteen clinical sites have been opened and study enrollment is tracking to our expectations.

“We look forward to resolving this matter expeditiously and to continue to advance our therapy to the benefit of patients suffering from RRMM.”