Grant Number:	1R01CA305818-01A1 Interpret this number
Primary Investigator:	Phillips, Siobhan
Organization:	Northwestern University
Project Title:	FIT2THRIVEMB: Optimization of a Physical Activity Promotion Intervention for Metastatic Breast Cancer Patients
Fiscal Year:	2026

PROJECT SUMMARY/ABSTRACT There are approximately 168,000 individuals living with metastatic breast cancer (MBC) in the United States and this number is expected to increase by 54% to ~250,000 from 2015 to 2030. MBC patients have poorer quality of life (QOL) and higher rates of functional decline and premature mortality compared to early-stage survivors and non-cancer controls. There is a paucity of research on health-enhancing interventions in MBC patients. Interventions are critically needed to alleviate adverse health effects and allow metastatic patients to function optimally in the years they survive with advanced cancer. Increased physical activity (PA) is consistently associated with fewer treatment-related side effects, higher QOL, increased survival and reduced recurrence and mortality among early-stage survivors. Increasing light intensity PA and reducing time spent sedentary may also reduce functional decline, improve QOL and reduce mortality independent of more intense PA. Existing studies of PA in MBC patients largely consist of small pilot trials of supervised PA using multicomponent interventions. Digital PA interventions may be particularly useful for these MBC patients because they allow for remote monitoring to enhance safety and tailoring and increase access for those who may be unable to travel to on-site, supervised PA sessions. Yet, no studies have examined a fully-powered digital PA intervention in MBC patients. We propose to address these critical research gaps by using Multiphase Optimization Strategy (MOST) methodology to determine which intervention components or component combinations optimally increase daily steps in a 12-week intervention with a 12-week follow-up. MOST is a framework adapted from engineering that uses highly efficient factorial experiments to evaluate individual, and combined, effects of intervention components to determine which ones can be reduced, eliminated, or replaced to improve efficiency. Insufficiently active MBC patients (n=224) will receive a core intervention consisting of the FIt2ThriveMB app and Fitbit and be randomly assigned to four components, each with two-levels, under consideration for inclusion in the optimized intervention: 1) EHR-integration (on v. off); 2) coaching dose (weekly v. bi-weekly; 3) social+ (on v. off) and 4) goal-setting type (highly tailored v. static). We will also examine the effects of increasing PA on symptom burden, other intensity activities (i.e. moderate to vigorous, light and sedentary), and functional performance and potential mediators and moderators of component effects. The proposed study represents the first systematic effort to use MOST to design an optimized, scalable digital PA intervention in MBC patients. Knowledge gained from this study will inform the development of more effective and scalable interventions to improve health and disease outcomes among this high need population.





None