PMID- 35000092 OWN - NLM STAT- MEDLINE DCOM- 20220318 LR - 20220318 IS - 1573-7217 (Electronic) IS - 0167-6806 (Linking) VI - 192 IP - 2 DP - 2022 Apr TI - Factors leading to alpelisib discontinuation in patients with hormone receptor positive, human epidermal growth factor receptor-2 negative breast cancer. PG - 303-311 LID - 10.1007/s10549-021-06476-1 [doi] AB - PURPOSE: Alpelisib is a phosphoinositide-3-kinase inhibitor approved for hormone-receptor-positive, PIK3CA-mutated metastatic breast cancer. However, length of drug exposure, maximum-tolerated dose, and therefore clinical response can vary significantly outside of the trial setting. This study evaluates our center's "real world" experience with alpelisib and focuses on duration of therapy and factors associated with cancer progression. METHODS: Patients receiving alpelisib at our center between 2019 and 2021 were identified. We evaluated duration of alpelisib therapy and the causative reasons for drug discontinuation. The association of drug duration and dose with subsequent cancer progression were assessed, along with the association between hyperglycemia during alpelisib therapy and cancer progression. RESULTS: Sixty-two women prescribed alpelisib were included (mean age 61 years). Disease progression was the most common reason for drug discontinuation, while discontinuation within 30 days was primarily attributed to adverse events (AEs). Among those who progressed, median time to progression was longer in those on alpelisib for > 90 days compared with those on alpelisib for 90 days compared to those receiving therapy for