In the Russian Federation on 05.10.2016 the American company Pfizer Inc. registered a commercial drug Ibrans (Palbocyclibe).
Ibrans is the first drug approved by the FDA from a new class of anti-cancer agents - inhibitors of cyclin-dependent kinases 4/6 (CDK 4/6).
Ibrans is recommended for postmenopausal women who have an estrogen receptor positive (ER +) metastatic breast cancer, a human epidermal growth factor 2 receptor negative (HER2-) metastatic breast cancer, and who have not previously received systemic therapy. Ibrans is prescribed together with the drug letrozole (letrozole), previously recommended by the FDA for the treatment of breast cancer in menopause.
In the study PALOMA-1 took part 165 women in postmenopause with the presence of ER-positive, HER2-negative common breast cancer, who were not treated at the metastatic stage of the disease. The subjects were randomly assigned to groups: 1) Ibrans together with letrozole, 2) only letrozole.
In the first group, the survival rate without signs of progression of the process was 20.2 months, in the second group - 10.2 months. Data on overall survival is currently not available.
Combination pallbocyclob + letrozole is characterized by good tolerability.
The most common side effects are neutropenia, leukopenia, fatigue and anemia.
Drug therapy it is recommended to start with a dosage of 125 mg - for 21 days, with a weekly break after. Before the beginning of treatment it is necessary to conduct a general blood test, and also before each subsequent cycle of therapy, and on the 14th day in the first two cycles of taking the drug.
Richard Pasdar, MD, Head of the Department of Hematology and Oncology at the Center for Evaluation and Research of Medicines, FDA believes that "the combined use of pablosiclib and letrozole provides a new treatment option for women diagnosed with metastatic breast cancer."
Complete drug instruction Ibrans here.