Nurix Therapeutics Presents Positive Results from the Ongoing Clinical Trial of Its BTK Degrader NX-5948 in Patients with Relapsed/Refractory Waldenstrom’s Macroglobulinemia

Nurix Therapeutics, Inc.
Nurix Therapeutics, Inc.

In This Article:

NX-5948 demonstrated robust clinical activity with objective responses observed in 7 of 9 (77.8%) evaluable Waldenstrom’s patients in the ongoing Phase 1a/1b clinical trial

Responses are durable and deepen over time with two patients on treatment for greater than one year

Data were presented at the 12th International Workshop on Waldenstrom’s Macroglobulinemia (IWWM-12)

SAN FRANCISCO, Oct. 19, 2024 (GLOBE NEWSWIRE) -- Nurix Therapeutics, Inc. (Nasdaq: NRIX), a clinical stage biopharmaceutical company developing targeted protein modulation drugs designed to treat patients with cancer and inflammatory diseases, today announced the presentation of clinical data from its ongoing Phase 1a/1b clinical trial of NX-5948, an orally bioavailable, brain penetrant degrader of Burton’s tyrosine kinase (BTK), in patients with relapsed/refractory Waldenstrom’s macroglobulinemia (WM) at the 12th International Workshop on Waldenstrom’s Macroglobulinemia (IWWM-12) which is being held in Prague, Czech Republic October 17–19, 2024.

“We are encouraged by the emerging positive data from NX-5948 in patients with Waldenstrom’s macroglobulinemia, which add to the previously disclosed robust clinical activity observed in patients with chronic lymphocytic leukemia,” said Paula G. O’Connor, M.D., chief medical officer of Nurix. “These data support our decision to advance NX-5948 into the ongoing Phase 1b expansion cohort in patients who have previously received at least one prior line of therapy including a BTK inhibitor and patients presenting with Bing-Neel syndrome, a rare form of WM with central nervous system involvement where NX-5948’s ability to penetrate the brain may offer a distinct advantage.”

The data presented at IWWM-12 included previously reported safety findings for all patients in the Phase 1a dose escalation study treated with NX-5948 at doses ranging from 50 mg to 600 mg once daily by oral administration regardless of diagnosis (n=79) based on an April 17, 2024 data cut. NX-5948 demonstrated a tolerable safety profile, and the safety profile for patients with WM was consistent with the safety profile for the overall population (WM patient safety data not shown separately).

New data from an October 10, 2024 data cut include the baseline characteristics of the first 13 patients with WM enrolled across both the Phase 1a and Phase 1b portions of the trial, clinical response assessments in 9 response-evaluable patients, and duration on study for all 13 patients. Among the 13 WM patients, the median age was 74 years and the median number of prior lines of therapy was 3. All 13 patients previously had been treated with both BTK inhibitors (BTKi) and chemotherapy/chemo-immunotherapy. Three patients (23.1%) had received prior treatment with the non-covalent BTKi pirtobrutinib, and one patient (7.7%) had received prior treatment with a BCL2 inhibitor. Baseline mutation status in MYD88 and CXCR4 was captured from patient records, and eight patients (61.5%) had mutations in MYD88, and two patients (15.4%) had mutations in CXCR4. Among the nine patients who were evaluable for response, seven patients (77.8%) had an objective response and two patients experienced stable disease (22.2%). All seven responses were observed at the first assessment at 8 weeks, and five remain on treatment with two patients on treatment for longer than one year. Responses were observed in patients regardless of their baseline mutations in MYD88 and CXCR4.