In the SWOG S1105 trial reported in the Journal of Clinical Oncology, Dawn L. Hershman, MD, MS, and colleagues found that a text message intervention did not reduce the rate of early discontinuation of adjuvant aromatase inhibitor therapy in postmenopausal women with early-stage breast cancer.
Dawn L. Hershman, MD, MS
In the trial, 702 women from 40 U.S. sites were randomly assigned to receive text messaging encouraging adherence to aromatase inhibitor therapy (n = 348) or no text messaging (n = 354). Patients had been taking aromatase inhibitors for > 30 days with a planned therapy duration of ≥ 36 months. Text messages were sent twice a week over 36 months; messages included statements on overcoming barriers to adherence and medication efficacy and reinforced the recommendation to take aromatase inhibitors. Patients were assessed for adherence every 3 months by urine assay and queries regarding adherence.
The primary outcome measure was time to adherence failure, defined as urine aromatase inhibitor metabolite assays showing levels < 10 ng/mL or undetectable levels or absence of a submitted specimen.
Adherence Failure Rates
Observed adherence at 36 months was 55.5% in the intervention group vs 55.4% in the control group. No significant difference in time to adherence failure was observed, with rates of adherence failure at 3 years being 81.9% in the intervention group vs 85.6% in the control group (hazard ratio [HR] = 0.89, P = .18). Rates at 1 and 2 years were 50.9% vs 57.2% and 70.4% vs 74.4%, respectively.
No significant differences were observed in rates of patient-reported aromatase inhibitor discontinuation, with 10.4% vs 10.3% reporting discontinuation at 3 years (HR = 1.16, P = .57). No significant differences in rates of study site-reported patient discontinuation were observed, with sites reporting discontinuation in 21.9% vs 18.9% at 3 years (HR = 1.31, P = .21).
The investigators concluded, “To our knowledge, this was the first large, long-term, randomized trial of an intervention directed at improving aromatase inhibitor adherence. We found high rates of aromatase inhibitor adherence failure. Twice-weekly text reminders did not improve adherence to [therapy]…improving long-term adherence will likely require personalized and sustained behavioral interventions.”
Dr. Hershman, of Columbia University Medical Center, is the corresponding author for the Journal of Clinical Oncology article.
Disclosure: The study was supported by a National Institutes of Health/National Cancer Institute/Division of Cancer Prevention grant, ASCO’s Conquer Cancer Foundation, and Breast Cancer Research Foundation. For full disclosures of the study authors, visit ascopubs.org.The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.