CBD Reduced Joint Pain in Breast Cancer Patients on Aromatase Inhibitors
Nearly 44% of breast cancer patients taking CBD for aromatase inhibitor joint pain achieved a meaningful reduction in worst pain over 15 weeks.
Quick Facts
What This Study Found
In a phase 2 clinical trial, 17 of 39 breast cancer patients (43.6%) taking CBD (Epidiolex, titrated to 100mg twice daily) achieved at least a 2-point reduction in worst pain from aromatase inhibitor therapy. Among the 28 who completed the study, average worst pain decreased by 2.36 points over 15 weeks.
Key Numbers
39 eligible patients enrolled. 28 completed treatment. 11 discontinued (5 toxicity, 6 patient preference). 17/39 (43.6%, 95% CI 28-60%) met primary endpoint. Worst pain improved 0.13 points per week (p<0.001). Completers: average 2.36-point pain reduction (95% CI -3.22 to -1.49). CBD dose: 100mg BID.
How They Did This
Phase 2 clinical trial of 39 women with stage 0-3 hormone receptor-positive breast cancer experiencing aromatase inhibitor-associated musculoskeletal symptoms. CBD (Epidiolex) titrated to 100mg twice daily over 4 weeks, total treatment 15 weeks. Used paired t-tests and linear mixed models.
Why This Research Matters
Aromatase inhibitor joint pain causes some breast cancer patients to stop life-saving cancer treatment. Finding a tolerable pain management option like CBD could improve both quality of life and cancer outcomes by keeping patients on their medication.
The Bigger Picture
AIMSS affects up to half of breast cancer patients on aromatase inhibitors, and current pain management options are limited. This pilot suggests CBD warrants further study, though it helped some patients and not others.
What This Study Doesn't Tell Us
No placebo control group. Small sample (39 patients). Open-label design allows placebo effects. 28% dropout rate. Pharmaceutical-grade CBD (Epidiolex) may differ from commercially available products.
Questions This Raises
- ?Which patients are most likely to benefit from CBD for AIMSS?
- ?Would a placebo-controlled trial confirm these results?
- ?Could different CBD dosing strategies improve tolerability and reduce dropouts?
Trust & Context
- Key Stat:
- 43.6% of patients achieved clinically meaningful pain reduction with CBD
- Evidence Grade:
- Small phase 2 trial without placebo control; promising but needs confirmation in larger randomized studies.
- Study Age:
- 2025 study
- Original Title:
- Pilot Study of Cannabidiol for Treatment of Aromatase Inhibitor-Associated Musculoskeletal Symptoms in Breast Cancer.
- Published In:
- Cancer medicine, 14(15), e71117 (2025)
- Authors:
- Fleege, Nicole M G(2), Miller, Elise A, Kidwell, Kelley M(2), Zacharias, Zeb R, Houtman, Jon, Scheu, Kelly, Kemmer, Kathleen, Boehnke, Kevin F, Henry, N Lynn
- Database ID:
- RTHC-06465
Evidence Hierarchy
A small preliminary study to test whether a larger study is feasible.
What do these levels mean? →Frequently Asked Questions
What is AIMSS?
Aromatase inhibitor-associated musculoskeletal symptoms (AIMSS) include joint pain, stiffness, and muscle aches caused by aromatase inhibitor drugs used to prevent breast cancer recurrence. These side effects cause some patients to stop their cancer treatment.
What type of CBD was used?
The study used Epidiolex, the only FDA-approved prescription CBD product. It was titrated to 100mg twice daily over 4 weeks. This is pharmaceutical-grade CBD, which may differ from over-the-counter products.
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Cite This Study
https://rethinkthc.com/research/RTHC-06465APA
Fleege, Nicole M G; Miller, Elise A; Kidwell, Kelley M; Zacharias, Zeb R; Houtman, Jon; Scheu, Kelly; Kemmer, Kathleen; Boehnke, Kevin F; Henry, N Lynn. (2025). Pilot Study of Cannabidiol for Treatment of Aromatase Inhibitor-Associated Musculoskeletal Symptoms in Breast Cancer.. Cancer medicine, 14(15), e71117. https://doi.org/10.1002/cam4.71117
MLA
Fleege, Nicole M G, et al. "Pilot Study of Cannabidiol for Treatment of Aromatase Inhibitor-Associated Musculoskeletal Symptoms in Breast Cancer.." Cancer medicine, 2025. https://doi.org/10.1002/cam4.71117
RethinkTHC
RethinkTHC Research Database. "Pilot Study of Cannabidiol for Treatment of Aromatase Inhibi..." RTHC-06465. Retrieved from https://rethinkthc.com/research/fleege-2025-pilot-study-of-cannabidiol
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.