Long-term CR Seen With Allo-CAR-NK Cell Therapy Plus Rituximab in Waldenstrom NHL

A pair of patients with Waldenstrom’s non-Hodgkins lymphoma (NHL) remain in complete remission (CR) after 7 and 15 months following treatment with an off-the-shefl chimeric antigen receptor (CAR) natural killer (NK) cell therapy alongside rituximab, according to leaders from ImmunityBio, who on Friday shared an update from an ongoing trial.¹

Durable CRs were seen in patients who had failed to response to current standard therapy. The treatment from ImmunityBio is the first chemotherapy-free, lymphodepletion-free CAR NK therapy to show 100% disease control in its first 4 patients, all of whom have been treated as outpatients, according to a statement from the company.¹

The update for the QUILT-106 clinical study (NCT06334991), which is ongoing, offered details for ImmunityBIo’s allogeneic cell therapy engineered to express a CD19-specific CAR NK and a high-affinity CD16 (FcγRIIIa 158V) receptor. The dual anti-tumor design creates a more potent tumor-fighting effect when paired with the anti-CD20 monoclonal antibody rituximab, as is the case in QUILT-106.¹

Rituximab targets CD20 on B cells,² and the QUILT-106 is using the combination regiment to treat Waldenström NHL, a rare B-cell malignancy whose patients have significant unmet need. Patients with Waldenström non-Hodgkins lymphoma who relapse or become refractory to available targeted and antibody-based therapies have limited options.¹

Patients received a total of 8 doses of cell therapy in the outpatient setting without lymphodepletion, which requires chemotherapy. Tumors were targeted with both CD19 and CD20 by infusing CD19 CAR NK cells with rituximab, 2 doses per cycle every 21 days for a total of 4 cycles (8 doses of NK-CAR and 6 doses of rituximab) and no further therapy thereafter. Responses were evaluated after 2 cycles.

The 2 patients in long-term follow-up remain in CR despite having no additional treatment, the company said in its statement.¹

Both the speed to remission and treatment’s durability show the potential for long-term immune-mediated disease control without continuous therapy, officials said, underscoring the current trend toward time-limited regimens that spare patients toxicity and achieve savings for health systems.³

“This updated follow-up reinforces the central thesis that restoring and activating the immune system can deliver durable control of disease without chemotherapy or lymphodepletion,” Patrick Soon‑Shiong, MD, ImmunityBio’s founder, executive chairman, and global chief medical and scientific officer said in a statement. “Seeing complete responses persist beyond a year after treatment has stopped, in patients who had exhausted available options, represents a meaningful advance for patients with this rare disease of Waldenström lymphoma and validates CAR-NK as a potential next-generation immunotherapy platform.”¹

In the 2 patients with evaluable follow up, 1 began with multiple lymphomatous bone lesions and 1 had with approximately 95% bone marrow infiltration by tumor cells. Both had complete responses after only 4 doses of CAR-NK plus rituximab.

Company officials said the patient with significant bone marrow involvement had complete bone morphological remission. In this patient, tumor cells had replaced 95% of the bone marrow, but after just 4 doses the patient achieved a CR that has now been maintained for 15 months, with no treatment beyond the scheduled 8 doses.

This approach “eliminates the need for cytotoxic conditioning for lymphodepletion or inpatient hospitalization, addressing key limitations associated with conventional CAR-T therapies,” ImmunityBio officials said in their statement.¹

“These data highlight a favorable safety and efficacy profile that is particularly important for patients with indolent yet incurable lymphomas,” Lennie Sender, MD, ImmunityBio chief medical officer for liquid tumors and cell therapy, said in the statement.¹So far, patients have not experienced any serious adverse events, Sender said.¹

ImmunityBio plans a follow-up study is that will combine the CAR-NK therapy, rituximab, and the company’s nogapendekin alfa inbakicept treatment, an immunotherapy marketed as Anktiva. This triplet will be evaluated in indolent lymphoma, including Waldenström’s macroglobulinemia.¹ At present, nogapendekin alfa inbakicept is approved by FDA with Bacillus Calmette-Guérin (BCG) to treat BCG-unresponsive nonmuscle invasive bladder cancer (NMIBC), specifically with carcinoma in situ.⁴

References

1. ImmunityBio announces durable complete response of 15 months with a chemotherapy-free CD19 CAR-NK cell therapy in Waldenstrom lymphoma. News release. ImmunityBIo. January 16, 2026. Accessed January 17, 2026. https://ir.immunitybio.com/news-releases/news-release-details/immunitybio-announces-durable-complete-response-15-months
2. Maloney DG. Mechanism of action of rituximab. Anticancer Drugs. 2001;12(suppl 2:S1-4.
3. Caffrey M. Time-limited regimens gain notice, offering a break for patients with blood cancer and savings for payers. Am J Manag Care. 2026;32(Spec 1):SP12.
4. FDA approves nogapendekin alfa inbakicept-pmln for BCG-unresponsive non-muscle invasive bladder cancer. News release. April 22, 2024. Accessed January 17, 2026. https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-nogapendekin-alfa-inbakicept-pmln-bcg-unresponsive-non-muscle-invasive-bladder-cancer