e18094 Background: Palbociclib has been approved as a first line therapy in hormone-receptor positive (HR+) and HER-2 negative metastatic breast cancer(MBC) manifesting significant improvement in progression free survival (PFS). We studied this drug in a community setting. The endpoints were estimated PFS, objective response, toxicities and patient outcomes. Methods: This was a single-center, retrospective study of HR+MBC patients receiving palbociclib after its FDA approval. 22 patients were selected Results: A total of 22 patients were included (Male = 2, Female = 20). Median age was 60-years (range, 49-84). About 90% patients had received at least one previous therapy and the median number was 1.5. 13% patients were on fulvestrant, 86% on letrozole and 4.5% on exemestane. About 64% of patients had ECOG status of ≥ 1. Median duration of palbociclib treatment was 5-months, therefore, an estimated PFS at 18-months was 50%. 4.5% patients attained complete response. 22% patients achieved partial response, 22% had stable disease and 50% patients demonstrated disease progression. 72% patients had neutropenia, of which 45% were grade ≥ 3. Thrombocytopenia and anemia were common (63% and 58%, respectively) but grade ≥ 3 thrombocytopenia or anemia was not observed. 50% patients required dose reductions and 18% required drug cessation owing to side effects. Conclusions: PFS was much lower as compared to actual trials in our real-world experience. Despite, several interesting observations were good objective response rates in males and HER-2+ patients underscoring its potential clinical efficacy in these subsets. Furthermore, apart from myelosuppressive side effects, pneumonitis was observed in one patient necessitating vigilance in clinical practice
Optimal regimen for treatment-naive hormone receptor-positive HER-2 negative metastatic breast cancer