Onconova Therapeutics, Inc. presented preclinical data on narazaciclib at the 17thInternational Conference on Malignant Lymphoma (ICML), which is taking place in Lugano, Switzerland, through June 17, 2023. Data from the Josep Carreras Leukaemia Research Institute expanded on a prior presentation at the recent American Association for Cancer Research (AACR) Annual Meeting, showing that narazaciclib's antitumor activity against mantle cell lymphoma (MCL) cell lines was superior to that of the FDA-approved CDK 4/6 inhibitors palbociclib and ribociclib, and similar to that of the FDA-approved CDK 4/6 inhibitor abemaciclib. Combining narazaciclib with the FDA-approved Bruton's tyrosine kinase inhibitor ibrutinib led to synergistic increases in antitumor activity against both ibrutinib-sensitive and ibrutinib-resistant MCL cell lines.

In addition, treatment with narazaciclib combined with ibrutinib led to significant inhibition of tumor growth and significant reductions in malignant B cell infiltration into the bone marrow in multiple chicken embryo chorioallantoic membrane xenograft models of MCL.