Talk Bio

Cardiff Oncology presented preclinical data at the AACR Annual Meeting 2026 (April 17–22, San Diego) on its oral PLK1 inhibitor onvansertib combined with trastuzumab deruxtecan (T-DXd) in HER2-low breast cancer models. 1 4 The combination demonstrated synergistic inhibition of cell viability in HER2-low breast cancer cell lines, including fulvestrant- and CDK4/6i-resistant cells, robust antitumor activity, tumor regression, and overcame resistance. 1 2 4 In resistant triple-negative and hormone receptor-positive models, the combo drove tumor regression in nearly all mice, with complete response rates up to 62%, improved growth inhibition, extended event-free survival, and favorable tolerability. 1 4 5 Poster titled 'PLK1 inhibitor onvansertib potentiates the antitumor efficacy of trastuzumab deruxtecan (T-DXd) and reverses its resistance in therapy-resistant HER2-low breast cancer models' presented April 19, 2026, 2:00–5: 00 PM PT (Abstract #329). 2 4 Sources: 1. htt...