AbbVie has helped Oncternal Therapeutics move a step closer to the start of a phase 3 trial by agreeing to supply the Bruton’s tyrosine kinase inhibitor ibrutinib for use in the study.
Oncternal is preparing to test zilovertamab, an antibody targeting a tyrosine-protein kinase transmembrane receptor called ROR1, in combination with ibrutinib, the active ingredient in Imbruvica, in patients with relapsed or refractory mantle cell lymphoma (MCL). The phase 3 study will randomize 250 patients to receive zilovertamab or placebo on top of ibrutinib to show whether the investigational candidate improves response rate and progression-free survival.
With the global registrational study set to start in the third quarter, Oncternal has entered into a clinical trial collaboration with AbbVie’s Pharmacyclics to secure supplies of ibrutinib. Oncternal CEO James Breitmeyer, M.D., Ph.D., set out the importance of the deal in a statement.
“This agreement represents a significant milestone for Oncternal as we advance towards the planned initiation of our registrational study ZILO-301 in the third quarter of 2022,” Breitmeyer said. “We are pleased that this collaboration will support the development of an innovative combination of zilovertamab and ibrutinib that we believe may address important unmet needs of patients with MCL.”
Oncternal ended March with $82.2 million in the bank, a sum that, following the deprioritization of the early-phase candidate ONCT-216, it expects to keep the lights on well into the third quarter of 2023. The forecast means the biotech is set to reach the end of its runway before it delivers data from the phase 3 trial of zilovertamab. Oncternal’s interim data could drop two years after the first patientis dosed, with final data taking another year.
Zilovertamab is the monoclonal antibody used in the ROR1-directed antibody-drug conjugate at the heart of Merck’s $2.75 billion takeover of VelosBio. While VelosBio used the antibody to get a payload to target cells, Oncternal sees potential to inhibit cancer growth and metastasis by blocking the WNT5A pathway.