Lilly's experimental breast cancer therapy abemaciclib has failed to hit interim efficacy targets in a late-stage combination trial, but the study will continue as planned on the recommendation of an independent data monitoring committee (DMC).

The MONARCH 2, Phase III trial is comparing a combination of abemaciclib plus fulvestrant (AstraZeneca's Faslodex) versus placebo with fulvestrant in women with hormone-receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) locally advanced or metastatic breast cancer.

"We had stringent criteria set for this interim analysis and we look forward to receiving the final MONARCH 2 results in the first half of 2017," said Richard Gaynor, senior vice president, product development and medical affairs for Lilly Oncology. "We remain optimistic that treatment with abemaciclib, in combination with fulvestrant could offer improved outcomes for patients."

The primary endpoint of the trial is progression-free survival, but overall survival and safety data will also be analysed, the firm noted.

Lilly is currently assessing its drug as a single agent in breast cancer patients with refractory metastatic breast cancer, whose disease had progressed following multiple prior treatments, including chemotherapy. Three other trials are also investigating abemaciclib in combination with other therapies.

Abemaciclib (LY2835219) is an investigational, oral cell cycle inhibitor, designed to block the growth of cancer cells by specifically inhibiting cyclin-dependent kinases, CDK 4 and CDK 6.