Oncternal Therapeutics, Inc. (NASDAQ:ONCT), a clinical-stage biopharmaceutical company focused on the development of novel oncology therapies, today announced that the rationale and plans for its upcoming Phase 3 ZILO-301 (zilovertamab plus ibrutinib targeting ROR1 for patients with Mantle Cell Lymphoma) clinical trial will be highlighted in a poster presentation at the European Hematology Association (EHA) 2022 Hybrid Congress. ZILO-301 is designed to evaluate the efficacy and safety of zilovertamab, an investigational anti-ROR1 monoclonal antibody, plus ibrutinib compared to ibrutinib monotherapy for the treatment of patients with relapsed or refractory mantle cell lymphoma (R/R MCL).
- Poster Title: Study ZILO-301: A Phase 3, Randomized, Double-Blind, Placebo-Controlled, Multicenter Study of Zilovertamab Plus Ibrutinib vs. Ibrutinib in Patients with Relapsed or Refractory Mantle Cell Lymphoma
- Abstract Number: P1154
- Session Title: Indolent and mantle-cell non-Hodgkin lymphoma - Clinical
- Session Date and Time: June 10, 2022 at 16:30 CEST
"The recently announced updated interim data from our Phase 1/2 study presented at ASCO 2022, provides ample support for the rationale of the design of our global registration Phase 3 study, ZILO-301, evaluating the combination of zilovertamab and ibrutinib in patients with MCL," noted Salim Yazji, M.D., Oncternal's Chief Medical Officer. "We are excited to pursue a registrational pathway for zilovertamab based on an innovative enrichment study design that we believe can provide both an accelerated approval and regular approval in a single study. We expect to initiate ZILO-301 in the third quarter of 2022."
Zilovertamab is being evaluated in combination with ibrutinib in patients with R/R MCL and chronic lymphocytic leukemia (CLL) in the Phase 1/2 study, CIRM-0001. The most recent interim data update showed an Objective Response Rate (ORR) of 85% and a Complete Response (CR) rate of 41% in 27 evaluable patients with mantle cell lymphoma, both of which compare favorably to the historical ORR of 66% and CR rate of 20% for ibrutinib monotherapy.
The phase 3 study, ZILO-301, will evaluate the potential benefit for patients who achieve either a partial response (PR) or stable disease (SD) during a lead-in with ibrutinib monotherapy. Initially, patients enrolled in ZILO-301 will receive single agent ibrutinib (560 mg daily) for 4 months. Patients with an inadequate response (PR or SD) will be randomized (1:1) to receive zilovertamab or placebo while continuing to receive ibrutinib. The study aims to randomize approximately 250 patients.
- Key Inclusion criteria:
- Adults with histologically confirmed MCL
- Relapsed or refractory with at least 1 prior therapy
- Primary Objective
- Progression-free survival (PFS) among subjects who had a PR or SD after open-label ibrutinib monotherapy phase and were randomized to receive zilovertamab + ibrutinib or ibrutinib + placebo
- Secondary Objectives
- Objective Response Rate (ORR) and Duration of Response (DoR)
- Complete Response Rate (CR Rate)
- Overall Survival (OS)
- Proportion of subjects experiencing grade 3 or 4 neutrophil count decrease and overall safety profile