Long-Term Safety Profile of Palbociclib With Endocrine Therapy
Posted: Tuesday, October 2, 2018
Treatment of patients with hormone receptor–/HER2-negative advanced breast cancer with the combination of palbociclib and endocrine therapy seems to have a manageable long-term safety profile, with no apparent cumulative or delayed toxicities. Véronique Diéras, MD, of the Institut Curie in Paris, and colleagues published the findings of their pooled analysis in the Journal of the National Cancer Institute, expanding on the data from the previous PALOMA trials.
“[This pooled analysis] represents the most comprehensive safety report of CDK4/6 inhibitor use for advanced breast cancer at this time,” commented the study authors.
Using data from the 3 previous PALOMA trials, the investigators focused on 872 patients who had received palbociclib with endocrine therapy and 471 patients who had received endocrine therapy alone; long-term (follow-up of 50 months) adverse event rates were assessed.
Hematologic toxicities were reported in 98.6% of patients receiving palbociclib and 3.6% of patients receiving endocrine therapy alone, with the most common hematologic adverse event being neutropenia. However, just 1.5% of patients with neutropenia in the palbociclib-treatment arm permanently discontinued treatment. Overall treatment discontinuation rates for both hematologic and nonhematologic adverse events were reportedly low at 8.3%, and the researchers concluded palbociclib-related toxicities could be well managed via dose reductions and temporary treatment discontinuations.
The researchers further suggested that investigating predictive markers for short- and long-term toxicity may improve the treatment’s clinical safety and efficacy.