A Phase III Randomized Trial of Metformin vs Placebo in Early Stage Breast Cancer
Summary
This study is looking at whether Metformin, an agent that is commonly used to treat diabetes, can decrease or affect the ability of breast cancer cells to grow and whether Metformin will work with other therapies to keep cancer from recurring. Health Canada has not approved the sale or use of Metformin to treat breast cancer, although they have approved its use in this clinical trial. Although Metformin is approved by the FDA for the treatment of diabetes, its use in breast cancer is considered investigational.
Timeline
- Start
- 2010-08-13
- Primary completion
- 2021-09-21
- Completion
- 2023-08-18
Outcome
Missed primary endpoint
registry analysis (superiority test); Metformin vs Placebo; p = 0.93; Hazard Ratio (HR) 1.01 (95% CI 0.84 to 1.21); Log Rank NCT01101438 ↗
registry analysis (superiority test); Metformin vs Placebo; p = 0.94; Hazard Ratio (HR) 1.01 (95% CI 0.87 to 1.17); Log Rank NCT01101438 ↗
Publications
- Background Goodwin PJ, Parulekar WR, Gelmon KA, Shepherd LE, Ligibel JA, Hershman DL, Rastogi P, Mayer IA, Hobday TJ, Lemieux J, Thompson AM, Pritchard KI, Whelan TJ, Mukherjee SD, Chalchal HI, Oja CD, Tonkin KS, Bernstein V, Chen BE, Stambolic V. Effect of metformin vs placebo on and metabolic factors in NCIC CTG MA.32. J Natl Cancer Inst. 2015 Mar 4;107(3):djv006. doi: 10.1093/jnci/djv006. Print 2015 Mar.
- Results Goodwin PJ, Chen BE, Gelmon KA, Whelan TJ, Ennis M, Lemieux J, Ligibel JA, Hershman DL, Mayer IA, Hobday TJ, Bliss JM, Rastogi P, Rabaglio-Poretti M, Mukherjee SD, Mackey JR, Abramson VG, Oja C, Wesolowski R, Thompson AM, Rea DW, Stos PM, Shepherd LE, Stambolic V, Parulekar WR. Effect of Metformin vs Placebo on Invasive Disease-Free Survival in Patients With Breast Cancer: The MA.32 Randomized Clinical Trial. JAMA. 2022 May 24;327(20):1963-1973. doi: 10.1001/jama.2022.6147.
- Goodwin PJ, Chen BE, Gelmon KA, Whelan TJ, Ennis M, Ligibel J, Stos PM, Shepherd LE, Parulekar WR, Stambolic V. Association of cancer antigen 15-3 with distant recurrence in immunohistochemically defined breast cancer subtypes in Canadian Cancer Trials Group MA.32. JNCI Cancer Spectr. 2026 Jun 25:pkag068. doi: 10.1093/jncics/pkag068. Online ahead of print.
- Liao L, Wang G, Li Y, Zou D, Liu J, Ma B, Ma J, Li Y, Qi Y, Ma J, Chen H. Nine-Year Recurrence-Free Survival in Gastric Signet-Ring Cell Carcinoma: A Case Report of Laparoscopic Radical Resection Combining Long-Term Systematic Therapy and Metformin Enteric-Coated Tablets. Case Rep Med. 2026 May 13;2026:6766219. doi: 10.1155/carm/6766219. eCollection 2026.
- Goodwin PJ, Chen BE, Gelmon KA, Whelan TJ, Ennis M, Lemieux J, Ligibel JA, Hershman DL, Mayer IA, Hobday TJ, Bliss JM, Rastogi P, Rabaglio-Poretti M, Thompson AM, Rea DW, Stos PM, Shepherd LE, Stambolic V, Parulekar WR. Effect of Metformin Versus Placebo on New Primary Cancers in Canadian Cancer Trials Group MA.32: A Secondary Analysis of a Phase III Randomized Double-Blind Trial in Early Breast Cancer. J Clin Oncol. 2023 Dec 10;41(35):5356-5362. doi: 10.1200/JCO.23.00296. Epub 2023 Sep 11.
Drugs
| Evaluation | Drug | Modality | Dose | Route |
|---|---|---|---|---|
| Subject | Metformin | Small molecule | 850 mg | Oral |