- Eli Lilly hopes to vault ahead of its competitors with its CDK 4/6 inhibitor abemaciclib, presenting data aimed to differentiating the drug from potential rivals like Pfizer's Ibrance and Novartis' developmental ribociclib, FierceBiotech reports.
- In a phase 1 study, abemaciclib was better tolerated than its competitors in treating a range of cancers, suggesting continuous dosing might be possible for the drug. Lilly is also presenting data from a phase 2 study in HR+/HER2- breast cancer next month at the annual meeting of the American Society of Clinical Oncology (ASCO).
- Pfizer's Ibrance, however, is quickly racing towards blockbuster status roughly a year post-launch, while a phase 3 trial of Novartis' ribociclib was stopped early due to positive results—suggesting Lilly may face stiff competition in the field.
Ibrance has already shifted the treatment paradigm in the breast cancer market. But now two other CDK4/6 inhibitors are aiming to muscle in, with Novartis' ribociclib generating strong results.
A phase 1 study of the drug in a range of cancers suggests Lilly may have an advantage with abemaciclib because of its dosing schedule, however. The other two drugs are intended to be dosed on a three week on/one week off schedule, thereby allowing patients' white blood cell counts to recover, so they are not depleted by severe neutropenia, FierceBiotech notes.
Abemaciclib, however, affected white blood counts less severely, possibly allowing the drug to be used more effectively as a monotherapy. Ibrance and ribociclib are intended to be used in combination with chemotherapy.
In another study, called MONARCH-1, Lily evaluated abemaciclib in 132 women with HR+/HER2- metastatic breast cancer who had already undergone chemotherapy or endocrine therapy. After eight months, median progression-free survival was 5.8 months and the confirmed overall response rate was 17.4%.
Lilly will be presenting additional data from this study at the upcoming American Society of Clinical Oncology (ASCO) meeting.