Trial results for a study investigating the dose timing of endocrine therapy for Breast Cancer were posted on ClinicalTrials.gov on 2026-01-08, with 245 participants enrolled.
Background
Endocrine therapy is a standard treatment for hormone receptor-positive breast cancer, but it can lead to significant side effects that impair quality of life. These side effects are well-recognized and can contribute to patients stopping or not fully complying with their treatment. Chronotherapy, or chronotherapeutics, involves administering medication in sync with the body's circadian rhythm to potentially reduce side effects and enhance efficacy. This study aimed to explore the impact of morning versus evening administration of endocrine therapy on tolerability and compliance.
Trial design
This completed study, designated as Phase 4, enrolled 245 participants with Breast Cancer. The trial was an open-label, randomized clinical trial designed to evaluate the effects of dose timing (morning versus evening) of endocrine therapy on tolerability and compliance. The primary outcome was not specified in the provided data, but key measurements focused on changes in endocrine toxicity and tolerability, as well as health-related quality of life scores.
Key results
The trial reported several key measurements related to changes in endocrine toxicity and tolerability, and health-related quality of life scores:
- Change in Endocrine Toxicity and Tolerability at 12 Weeks:
- For Morning Administration of Endocrine Therapy, the mean change was -2.2 (Standard Deviation 14.1 units on a scale).
- For Evening Administration of Endocrine Therapy, the mean change was -5.0 (Standard Deviation 16.8 units on a scale).
- Change in Endocrine Toxicity and Tolerability (first reported measurement):
- For Morning Administration of Endocrine Therapy, the mean change was -0.3 (Standard Deviation 12.6 units on a scale).
- For Evening Administration of Endocrine Therapy, the mean change was -0.5 (Standard Deviation 14.6 units on a scale).
- Change in Endocrine Toxicity and Tolerability (second reported measurement):
- For Morning Administration of Endocrine Therapy, the mean change was -1.6 (Standard Deviation 13.7 units on a scale).
- For Evening Administration of Endocrine Therapy, the mean change was -2.3 (Standard Deviation 13.6 units on a scale).
- Change in Endocrine Toxicity and Tolerability (third reported measurement):
- For Morning Administration of Endocrine Therapy, the mean change was -2.2 (Standard Deviation 14.1 units on a scale).
- For Evening Administration of Endocrine Therapy, the mean change was -5.0 (Standard Deviation 16.8 units on a scale).
- Change in Endocrine Toxicity and Tolerability (fourth reported measurement):
- For Morning Administration of Endocrine Therapy, the mean change was -3.0 (Standard Deviation 18.7 units on a scale).
- For Evening Administration of Endocrine Therapy, the mean change was -4.7 (Standard Deviation 15.6 units on a scale).
- Change in Health Related Quality of Life Scores:
- For Morning Administration of Endocrine Therapy, the mean change was 1.9 (Standard Deviation 12.0 units on a scale).
- For Evening Administration of Endocrine Therapy, the mean change was 1.2 (Standard Deviation 11.6 units on a scale).
What this means
The results suggest that administering endocrine therapy in the evening may lead to a greater reduction in endocrine toxicity compared to morning administration, as indicated by several mean change measurements. For instance, one key measurement showed a mean reduction of -5.0 for evening administration versus -2.2 for morning administration. This finding could have implications for improving patient tolerability and adherence to long-term endocrine therapy for breast cancer. While changes in health-related quality of life scores were also measured, the observed differences between morning and evening administration were smaller. No statistical significance or comparative analyses were provided in the posted data.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for the study NCT04864405, titled "Evaluating the Dose Timing (Morning vs Evening) of Endocrine Therapy and Its Effects on Tolerability and Compliance", were posted on 2026-01-08 on clinicaltrials.gov.