A Phase 3 trial investigating accelerated radiation therapy for Breast Cancer, NCT04175210, reached primary completion on 2025-07-15, with 397 participants enrolled.
Background
Breast cancer remains a significant global health challenge, with radiotherapy being a cornerstone of treatment for many patients following surgery. Standard radiation regimens often involve daily treatments over several weeks, which can be burdensome for patients due to travel, time commitment, and potential side effects. Accelerated radiation therapy aims to deliver the same therapeutic effect in a shorter timeframe, potentially improving patient convenience and adherence while maintaining efficacy and an acceptable toxicity profile. Investigating shorter regimens is crucial for optimizing breast cancer care.
Trial design
This Phase 3 randomized study, titled "Prospective Randomized Study of Accelerated Radiation Therapy (PRART)", enrolled 397 participants with Stage 0 ductal carcinoma in situ (Tis (DCIS), Stage T1-T2, lymph node negative (N0) breast cancers. Participants were randomized to receive whole breast radiotherapy with a concomitant boost to the tumor bed. Arm 1, the standard arm, involved radiation over 15 fractions (4050cGY and Boost to Tumor Bed of 4800cGY). Arm 2, the experimental arm, involved radiation over 10 fractions (3200cGY and Boost to Tumor Bed of 4200cGY). The primary endpoint was the "Proportion of Patients With Acute Toxicity Grade ≥ 2 on the 10-fraction Arm Compared to Proportion of Patients With Acute Toxicity Grade ≥ 2 on the 15-fraction Arm Evaluated up to 1-month Post-radiation Treatment".
Key results
The trial reported the proportion of patients with acute toxicity Grade ≥ 2 evaluated up to 1-month post-radiation treatment for both arms:
- For ARM 1 (15-fractions), the proportion of participants with acute toxicity Grade ≥ 2 was 0.1624365482233.
- For ARM 2 (10-fractions), the proportion of participants with acute toxicity Grade ≥ 2 was 0.095.
What this means
The primary completion data suggests that the experimental 10-fraction accelerated radiation therapy regimen for breast cancer resulted in a lower proportion of acute toxicity Grade ≥ 2 compared to the standard 15-fraction regimen within one month post-treatment. This finding indicates a potential benefit of the shorter regimen in terms of reducing immediate side effects for patients. While these results focus on acute toxicity, further analysis would be needed to assess long-term toxicity, local control, and overall efficacy to fully understand the clinical implications of this accelerated approach for breast cancer treatment.
Source
The information regarding the primary completion of this trial was obtained from ClinicalTrials.gov, a public database of clinical studies. The event, "Phase 3 primary completion: NCT04175210", was recorded on 2025-07-15 on clinicaltrials.gov.