The drug is approved in combination with letrozole, to treat postmenopausal women with estrogen receptor-positive, human epidermal growth factor receptor 2-negative (ER+/HER2-) advanced breast cancer as initial endocrine-based therapy for their metastatic disease.
The combination was approved for this indication under accelerated approval based on progression-free survival (PFS).
The company said that the continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial.
The new drug application (NDA) of Ibrance was based on the final results of the Phase II PALOMA-1 trial and the most frequently reported adverse event for the combination was neutropenia.
According to the company, the confirmatory Phase III trial, PALOMA-2, is now fully enrolled.
Pfizer chairman and CEO Ian Read said: "I am proud of the clinical program for Ibrance, which was discovered in Pfizer laboratories, and the innovation we are able to bring forward to the breast cancer community today.
"The registration trial showed that, compared to letrozole alone for first-line treatment of ER+/HER2- advanced breast cancer, IBRANCE in combination with letrozole almost doubled the time before tumor progression, delaying the need for later-line therapies including other hormonal agents and chemotherapies."