CART-ddBCMA Produces Deep, Durable Responses in Early Phase 1 Results for RRMM

"When you think about some the challenges with CAR Ts...they've been really limited to a handful of indications. With ARC-SparX, we believe we can get into more difficult-to-treat indications. For example, we're going after acute myeloid leukemia next." —Rami Elghandour, Chairman & CEO, Arcellx

One of the key factors to cell therapy is accessibility, and Rami Elghandour, chairman and CEO of Arcellx, is trying to change that.

"Cell therapies are obviously a very innovative and very impactful technology, but they've historically been very limited in their use," Elghandour tells CGTL in a video interview. "Really at the core of the founding of Arcellx was engineering cell therapies and immunotherapies that can really be much more broadly accessible...and expanding access to many more patients who can benefit."

Arcellx focuses on developing cell therapies in areas of high unmet need, and its pipeline features a number of clinical programs in multiple myeloma, myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML), as well as solid tumors.

The company leverages D-Domain technology, a synthetic binding scaffold, that has the potential to enable higher transduction efficiency, high cell surface expression, and low tonic signaling.

"When you transduce your cells using a viral vector to produce a CAR T therapy, a higher percentage of our cells are CAR-positive, or, in effect, they would be tumor-identifying and killing," Elghandour said. "As a result of having that higher transduction efficiency, we can, in effect, have a lower overall total cell dose, which we believe can contribute to having a therapy that is both effective and more tolerated, o r the potential for a better safety profile."

Phase 1 data (NCT04155749) on CART-ddBCMA, one of Arcellx's CAR T-cell therapies powered by the D-Domain, were published recently in Blood Advances.¹ CART-ddBCMA, which targets the BCMA antigen, contributed to a 100% overall response rate and a nearly 70% complete response rate in patients with relapsed and refractory multiple myeloma, according to Elghandour.

"These are obviously early results but they're very encouraging results," he said. "We have an upcoming presentation at the ASCO meeting in June where we're excited to show further results."

Reference:

Frigault MJ, Bishop MR, Rosenblatt J, et al. Phase 1 Study of CART-ddBCMA for the treatment of subjects with relapsed and refractory multiple myeloma [published online ahead of print, 2022 Apr 25]. Blood Adv. 2022;bloodadvances.2022007210. doi:10.1182/bloodadvances.2022007210