Lilly wins the breast cancer adjuvant race
Sales of Lilly’s CDK4/6 inhibitor Verzenio are still forecast to lag those of Pfizer’s rival Ibrance in breast cancer, but since the latter’s blow-up in the Pallas trial in mid-2020 expectations for the two products have converged. The FDA today greenlit Verzenio for the adjuvant treatment of patients with HR-positive, Her2-negative, node-positive breast cancer at high risk of recurrence and with a Ki-67 score of at least 20%. Ki-67 score is a marker of cellular proliferation, and the requirement could reduce Verzenio’s addressable market markedly. Ibrance does not have approval in the adjuvant setting – that was what Pallas was intended to accomplish – but competition for Verzenio here could yet arrive in the shape of Kisqali. The Natalee trial assessing Novartis’s CDK4/6 inhibitor is due to report towards the end of next year, though an interim cut could arrive before then. Natalee enrolled intermediate as well as high-risk patients. Since the success of Verzenio’s MonarchE trial was attributed to the fact that it only recruited patients at high risk of disease recurrence it is possible Natalee could follow Pallas into failure. All three are already approved in a metastatic setting.