T-DM1 Breast Cancer Treatment Could Lack Side Effects

Unfortunately, while a variety of treatment options exist for different conditions, many come with unwanted adverse reactions or side effects. However, this might soon change for patients with HER2 positive breast cancer. According to Medical XPress, data from the Phase 2 PREDIX HER2 clinical trial evaluated trastuzumab emtansin (T-DM1) for patients with HER2 positive breast cancer. During this study, researchers determined that this treatment combination may be just as effective as the current standards-of-care, while also offering fewer adverse reactions. 

Interested in learning more? Check out the full published data in JAMA Oncology.


According to the National Cancer Institute (NCI), T-DM1 is:

A drug used to treat certain patients with HER2-positive breast cancer that has already been treated with trastuzumab and a type of anticancer drug called a taxane. T-DM1 contains a monoclonal antibody called trastuzumab that binds to a protein called HER2, which is found on some breast cancer cells, [and] also contains an anticancer drug called DM1, which may help kill cancer cells.

Within this study, researchers wanted to understand the safety and efficacy of T-DM1 treatment as opposed to the current standard-of-care, which consists of trastuzumab, pertuzumab, and docetaxel. Altogether, researchers sought to understand how effective the treatments were compared to how many side effects they prompted. During the course of the study, patients received 6 treatments every 3rd week. The median follow-up period was 40.4 weeks. Findings included:

  • Both T-DM1 and trastuzumab, pertuzumab, and docetaxel showed efficacy in treating patients with HER2 positive breast cancer.
  • Through testing and analysis, researchers determined that both patient groups saw pathologic complete responses. 
  • Patients treated with T-DM1 had significantly fewer, and more mild, side effects. Additionally, this same patient group reported a higher quality of life (QOL).

While these results show promise, researchers hope to replicate these findings in future trials before any definitive ruling can be made.

Breast Cancer

As the name suggests, breast cancer occurs in breast cells. While it may affect both males and females, breast cancer is significantly more common in females. In fact, it is the 2nd most common female cancer! Generally, the cause of breast cancer is unknown. However, up to 10% of cases are caused from BRCA gene mutations. Additional risk factors include obesity, early menstruation or late menopause, older age, radiation exposure, never having been pregnant, or alcohol consumption.

There are also multiple breast cancer subtypes, such as triple-negative breast cancer or, as described above, HER2 positive breast cancer. This form of breast cancer tests positive for human epidermal growth factor receptor 2 (HER2), which promotes cancer cell growth. Because of this, HER2 positive breast cancer is considered a fairly aggressive subtype.

Symptoms related to breast cancer include: 

  • Inverted nipples
  • Nipple discharge
  • A change in the breast’s size, shape, or appearance
  • Breast skin redness
  • Dimpling, peeling, scaling, crusting, flaking, or pitting of the breast skin

Learn more about breast cancer.

Jessica Lynn

Jessica Lynn

Jessica Lynn has an educational background in writing and marketing. She firmly believes in the power of writing in amplifying voices, and looks forward to doing so for the rare disease community.

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