Positive results from SOLAR-1 trial of BYL 719 + fulvestrant for (HR+/HER2-) PIK3CA-mutant advanced or metastatic breast cancer .- Novartis.

Novartis announced the global Phase III SOLAR-1 trial evaluating the investigational alpha-specific PI3K inhibitor BYL 719 (alpelisib) has met the primary endpoint showing an improvement in progression-free survival (PFS). SOLAR-1 is evaluating BYL 719 in combination with fulvestrant compared to fulvestrant alone in postmenopausal women and men with hormone-receptor positive, human epidermal growth factor receptor-2 negative (HR+/HER2-) PIK3CA-mutant advanced or metastatic breast cancer that progressed on or following aromatase inhibitor treatment with or without a CDK4/6 inhibitor.

"BYL719 is the only alpha-specific PI3K inhibitor and the first one to show potential increased benefit and acceptable tolerability for patients," said Samit Hirawat, MD, Head, Novartis Oncology Global Drug Development. "We are encouraged by the results observed in the SOLAR-1 study and look forward to submitting the data to an upcoming medical congress and starting discussions with health authorities worldwide."

Currently, there are no approved PI3K inhibitors for HR+ advanced breast cancer. The PI3K pathway plays an important role in regulating cell processes and is the most frequently altered pathway promoting tumor growth, disease progression and treatment resistance in HR+ advanced breast cancer. Adverse events observed with investigational BYL 719 in combination with fulvestrant in SOLAR-1 were generally consistent with those observed in previous BYL 719 and fulvestrant studies. The SOLAR-1 trial will continue to assess data for secondary endpoints. Novartis will begin discussions with global health authorities based on these results.