NXC-201 Elicits High Complete Response Rate in R/R AL Amyloidosis

Treatment with NXC-201, a sterically optimized BCMA-directed CAR T-cell therapy, produced a high level of complete response (CR) in patients with relapsed/refractory light chain (AL) amyloidosis, according to an interim update from the phase 1b/2 NEXICART-2 trial (NCT06097832).¹

Findings showed that evaluable patiens (n = 45) achieved a CR rate of 89%, as assessed by an independent review committee, Among 25 patients added to the analysis since the prior update, all achieved either a CR (n = 21) or minimal residual disease (MRD) negativity (n = 4). According to a news release from Immix Biopharma, all patients in the trial who previously achieved MRD negativity went on to reach a CR within 1 year of treatment; if the 4 patients who are currently MRD negative convert to CR, the CR rate could reach up to 98% (n = 44/45). No relapses have been observed to date among patients who achieved a CR or MRD negativity.

Regarding safety, no neurotoxicity or enterocolitis was reported.

Final data from NEXICART-2 are expected to read out in 2027, and Immix plans to submit a biologics license application (BLA) to the FDA for NXC-201 in the relapsed/refractory AL amyloidosis setting at that time. NXC-201 holds breakthrough therapy, regenerative medicine advanced therapy, and orphan drug designations from the FDA, as well as orphan drug designation from the European Medicines Agency.

"Today, patients with AL Amyloidosis face years of burdensome, continuous treatment. As a potential one-and-done treatment option, NXC-201 could liberate patients from that burden. We are thrilled with NXC-201's magnitude of effect across a broad range of relapsed/refractory AL Amyloidosis patients in NEXICART-2," Ilya Rachman, MD, PhD, chief executive officer of Immix Biopharma, stated in a news release.

How was NEXICART-2 designed?

The open-label, multicenter phase 1b/2 NEXICART-2 trial, which the company describes as registrational, enrolled 45 patients across 18 sites in the United States.^1,2 Eligible patients were at least 18 years of age with histologically confirmed systemic AL amyloidosis with measurable hematologic disease, and symptomatic organ involvement of the heart, kidney, liver/gastrointestinal tract, or peripheral nervous system.² Patients needed to have received at least 1 prior line of therapy containing an anti-CD38 monoclonal antibody and a proteasome inhibitor and could not be in very good partial response or better at enrollment. An ECOG performance status of 0 to 2 was also required.

Key exclusion criteria included prior CAR T-cell or BCMA-directed therapy, stage IIIb cardiac disease, New York Heart Association class III or IV heart failure, a left ventricular ejection fraction below 35%, and bone marrow plasma cells exceeding 30% with clinically symptomatic multiple myeloma.

Patients underwent leukapheresis at least 1 month before lymphodepletion with cyclophosphamide at 250 mg/m² and fludarabine at 25 mg/m² on days –5, –4, and –3, followed by a single infusion of NXC-201 on day 0.

The primary end points were the incidence and severity of adverse effects, with cytokine release syndrome and immune effector cell–associated neurotoxicity syndrome graded per ASTCT consensus criteria, as well as confirmation of the maximum tolerated dose and recommended phase 2 dose. A secondary end point was the rate of hematologic and organ response per 2012 consensus criteria.

What’s next for the development of NXC-201?

NXC-201 is also slated for evaluation in the newly diagnosed setting in the randomized phase 3 NEXICART-3 trial (NCT07709715), which plans to compare the CAR T-cell therapy with daratumumab (Darzalex) plus cyclophosphamide, bortezomib (Velcade), and dexamethasone (CyBorD) in 260 patients with newly diagnosed systemic AL amyloidosis.³

"NXC-201's complete response rate continues to increase over time, even as reported patient counts have now more than doubled. We look forward to final readout, BLA submission and potentially making NXC-201 available to relapsed/refractory AL Amyloidosis patients at commercial launch," Gabriel Morris, president of Immix Biopharma, added in a news release.¹

References

1. Immix Biopharma announces 89% complete response rate at interim update across all NEXICART-2 patients, with MRD-negativity indicating potential to reach up to 98% complete response rate, supporting potential best-in-class therapy for relapsed/refractory AL amyloidosis. News release. Immix Biopharma. September 29, 2026. Accessed September 30, 2026. https://www.globenewswire.com/news-release/2026/09/29/3370648/0/en/immix-biopharma-announces-89-complete-response-rate-at-interim-update-across-all-nexicart-2-patients-with-mrd-negativity-indicating-potential-to-reach-up-to-98-complete-response-ra.html
2. Study of NXC-201 CAR-T in patients with light chain (AL) amyloidosis (NEXICART-2). ClinicalTrials.gov. Updated July 14, 2026. Accessed September 30, 2026. https://clinicaltrials.gov/study/NCT06097832
3. A randomized phase 3 study to evaluate the efficacy and safety of NXC-201 compared with daratumumab with cyclophosphamide, bortezomib and dexamethasone (CyBorD) in newly diagnosed systemic AL amyloidosis (NEXICART-3). ClinicalTrials.gov. Updated July 16, 2026. Accessed September 30, 2026. https://clinicaltrials.gov/study/NCT07709715