Anito-cel Advances Toward Pivotal Phase 3 Study as Kite and Arcellx Share iMMagine-3 Trial Design

Kite, a Gilead Company, and Arcellx have unveiled crucial details on their collaborative Phase 3 clinical investigation, iMMagine-3, which will evaluate the efficacy and safety of anito-cel in multiple myeloma patients. The global randomized controlled trial represents a significant milestone for this BCMA CAR T therapy and addresses a considerable treatment gap in the relapsed and/or refractory segment.

iMMagine-3 Trial Architecture and Patient Population

The iMMagine-3 study targets approximately 450 adult patients with relapsed or refractory multiple myeloma who have undergone one to three prior treatment lines, including exposure to both an immunomodulatory drug (IMiD) and an anti-CD38 monoclonal antibody. This patient population represents an emerging clinical need, particularly as anti-CD38 therapies move into front-line treatment settings.

The trial will compare anito-cel against standard-of-care regimens, which investigators may select from pomalidomide-bortezomib-dexamethasone (PVd), daratumumab-pomalidomide-dexamethasone (DPd), carfilzomib-daratumumab-dexamethasone (KDd), or carfilzomib-dexamethasone (Kd). Patients receiving anito-cel will undergo leukapheresis followed by optional bridging therapy, lymphodepleting chemotherapy with fludarabine and cyclophosphamide, and a single infusion of anito-cel (115×10⁶ CAR+ T cells) on Day 1.

Primary and Secondary Endpoints

Progression-free survival (PFS) serves as the primary endpoint, measured through blinded independent review using the 2016 IMWG uniform response criteria. Key secondary endpoints encompass complete response rates (CR/sCR), minimal residual disease negativity, overall survival, and comprehensive safety assessments.

Manufacturing and Trial Launch Timeline

The technical transfer of anito-cel manufacturing from a third-party contract manufacturing organization to Kite’s Frederick, Maryland facility has been completed. This manufacturing shift enables Kite to produce anito-cel for the iMMagine-3 investigation, leveraging the company’s established cell therapy production infrastructure. The trial is anticipated to launch in the second half of 2024 across approximately 130 study sites spanning North America, Europe, and international regions.

Anito-cel’s Technological Advantage

Anito-cel incorporates Arcellx’s proprietary D-Domain binder technology, a compact 8kDa CAR design that promotes enhanced T-cell transduction and elevated CAR expression per individual T-cell. This structural innovation generates higher quantities of CAR-positive cells compared to conventional approaches. The FDA has designated anito-cel with Fast Track, Orphan Drug, and Regenerative Medicine Advanced Therapy designations.

Strategic Partnership and Previous Trial Progress

Kite and Arcellx jointly develop and commercialize anito-cel for the United States, while Kite retains commercialization rights for markets outside the U.S. The companies remain on schedule to present preliminary iMMagine-1 trial data by year-end, with the Phase 3 iMMagine-3 program positioned to build upon these findings.

Cindy Perettie, Executive Vice President at Kite, emphasized that “manufacturing quality, reliability and speed are critical as every day matters for these patients.” Rami Elghandour, Arcellx’s Chairman and Chief Executive Officer, noted that the iMMagine-3 design “captures what will become the largest second-line patient population based on current treatment paradigm shifts,” enabling broader and earlier patient access to this novel cell therapy candidate.