The safety and efficacy of palbociclib in older patients with advanced breast cancer in a real-world setting

Aims:Palbociclib has been approved in combination with endocrine therapy(ET)for hormone receptor-positive(HR+)/human epidermal growth factor receptor 2-negative(HER2-)advanced breast cancer(ABC),regardless of age.Even though ABC is one of the most prevalent cancers in older patients,very few patients≥65 years old were included in pivotal trials.Therefore,the current study evaluated the safety and efficacy of palbociclib in“real-world”routine treatment of unselected older patients with HR+/HER2-ABC.Methods:Data were collected on patients>70 years old who were treated with palbociclib plus ET for HR+/HER2-ABC in our institution.We analyzed safety data(CTCAE v4.0 criteria)and outcomes,such as progression-free survival(PFS)and overall survival(OS),as well as any associations between main geriatric characteristics and our results.Furthermore,we assessed safety at a national level by analyzing all palbociclib-related adverse events(AEs)reported in the French Pharmacovigilance Database(FPVD)during the same period.Results:From February 2016 to July 2019,52 patients were identified with a median age of 80.9 years,of whom 88%presented an AE.The most common grade 3-4 AE was neutropenia(64%).Median PFS and OS were nine months and not reached,respectively.The FPVD reports 227 cases of palbociclib-related AEs,with older and younger patients sharing similar characteristics.Conclusion:Palbociclib is well tolerated in older patients with efficacy comparable to that in younger patients.However,the addition of palbociclib to ET should be evaluated individually in this older and frailer subgroup.