A Pharmacometric Analysis of Patient-Reported Outcomes in Breast Cancer Patients Through Item Response Theory

• DOI: 10.1007/s11095-018-2403-8
• Publication Date: 2018-04-19T15:41:19Z
• Authors: Emilie Schindler; Lena E. Friberg; Bertram L. Lum; Bei Wang; Angelica Quartino; Chunze Li; Sandhya Girish; Jin Y. Jin; Mats O. Karlsson
• Keywords: Lapatinib; Trastuzumab emtansine

An item response theory (IRT) pharmacometric framework is presented to characterize Functional Assessment of Cancer Therapy-Breast (FACT-B) data in locally-advanced or metastatic breast cancer patients treated with ado-trastuzumab emtansine (T-DM1) capecitabine-plus-lapatinib. In the IRT model, four latent well-being variables, based on FACT-B general subscales, were used describe physical, social/family, emotional and functional well-being. Each subscale was reassigned one other subscales. Longitudinal changes responses covariate effects investigated. The model could both item-level subscale-level data. Non-Asian showed better baseline social/family than Asian patients. Moreover, Eastern Cooperative Oncology Group performance status 0 had physical Well-being described as initially increasing decreasing before reaching a steady-state, which varied substantially between T-DM1 exposure not related any variables. Physical worsening identified capecitabine-plus-lapatinib-treated patients, whereas T-DM1-treated typically stayed stable. developed provides thorough description longitudinal It acknowledges multi-dimensional nature questionnaire allows be evaluated responses.