Onconova announces presentation of new preclinical data on narazaciclib

Onconova Therapeutics announced new preclinical data on narazaciclib in two poster presentations at the American Association for Cancer Research, AACR, Annual Meeting. Poster 5987: Differential targets engaged by narazaciclib in comparison to the approved CDK 4/6 inhibitors contribute to enhanced inhibition of tumor cell growth. Featured in this poster are data characterizing narazaciclib’s mechanism of action and activity in preclinical cancer models. Results showed that, in addition to inhibiting kinases such as CDK 4/6, narazaciclib treatment led to the degradation of other kinases not targeted by the FDA-approved CDK 4/6 inhibitor palbociclib. These kinases included BUB1, the overexpression of which was shown to be associated with poor prognosis in breast cancer and uterine corpus endometrial carcinomas. Poster 5974: Synergistic activity of the CDK 4/6 antagonist narazaciclib with irreversible BTK inhibition in ibrutinib-resistant mantle cell lymphoma. Data featured in this poster demonstrate narazaciclib’s potent antitumor activity against mantle cell lymphoma cell lines, independent of their sensitivity to the FDA-approved Bruton’s tyrosine kinase inhibitor ibrutinib. Narazaciclib’s activity against MCL cell lines was shown to be 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 ibrutinib led to synergistic increases in antitumor activity against both ibrutinib-sensitive and ibrutinib-resistant MCL cell lines.