The Chemo-Gut Trial: A double-blind randomized controlled trial investigating the effects of a multi-strain probiotic on gut microbiota, gastrointestinal symptoms, and psychosocial health in cancer survivors


The purpose of this study is to find out what effects a multistrain probiotic has on your gastrointestinal and psychosocial symptoms, and your gut microbiome after treatments for cancer. Specifically, we are trying to determine whether it is better to receive the probiotic, or nothing. To do this, some of the participants in this study will get the probiotic and some will receive a placebo (a substance that looks the same as the probiotic but does not have any active or medicinal ingredients). The placebo in this study is not intended to have any effect on your gastrointestinal and/or psychosocial symptoms or be of benefit to you. A placebo is used to make the results of the study more reliable.


Currently recruiting participants: Yes

Eligible ages: 18 to 100

Inclusion criteria:

You may be eligible for this study if you meet the following criteria:
1. Male, female, or non-binary person of any ethnicity
2. Aged 18 years or older
3. Diagnosed with a hematological cancer (leukemia, Hodgkin’s, and non-Hodgkin lymphoma), breast, osteosarcoma, Ewing’s sarcoma, gynecological (cervical, endometrial), prostate, or testicular cancer
4. Stages I – IV, or metastatic cancer IF you are stable and off treatment
5. Have received chemotherapy (with or without radiation, surgery, or hormone therapy)
6. Have completed primary cancer treatments (e.g. chemotherapy, radiation)
7. You are within 5 years from your final cancer treatments
8. Not currently pregnant or planning to become pregnant during the 12-week study
9. You experience clinically elevated levels of gastrointestinal (e.g. abdominal pain) and/or psychosocial symptoms (e.g. depression, anxiety) that began during or after treatments for cancer
10. Able to provide fecal samples
11. Fluent in English, and have access to a computer, smartphone, or tablet with internet access to complete questionnaires
12. Provide written informed consent

Exclusion criteria:

You will NOT be eligible for this study if you meet any of these criteria:
1. Diagnosis of central nervous system tumor, or colorectal cancer
2. Taken antibiotics and/or daily probiotic (including probiotic yogurt) within the 1 month prior to study participation (but you may be eligible after this 1 month has passed)
3. Currently or previously receiving immunotherapy
4. Diagnosed with irritable bowel syndrome or inflammatory bowel disease prior to being diagnosed with cancer
5. Diagnosed with a developmental/cognitive delay prior to cancer (e.g. autism spectrum disorder, downs syndrome)


Fill out the following form if you want to participate in this research

Method of contact

Additional information

Contact information

Please email Dr. Julie Deleemans and note "Chemo-Gut Probiotic Trial" in the subject line:

Principal investigator:

Linda Ellen Carlson

Clinical trial: