This is a single-center, investigator-initiated, non-interventional study evaluating the role of the intestinal microbiome and autoimmune panels as a predictor for developing ≥ Grade 2 CTCAE v5.0 immune-related adverse event (irAE) and/or requiring systemic immunosuppression for irAEs in advanced solid tumor patients receiving immunooncology (IO) combinations at the Princess Margaret Cancer Centre. This is a minimal risk study involving the analysis of patient samples and does not involve therapeutic intervention.

The study will involve a prospective cohort of up to 120 patients and it is anticipated that patient accrual will be completed within 18 months.

Patients will receive IO combination as per their specific protocols from their other clinical trial or per their standard of care and samples will be collected at multiple time-points. No additional visits to the hospital will be needed for this study as safety assessments are already captured for all patients based on their participation in a clinical trial or per their standard of care.

Accumulating evidence supports that differential composition of fecal microbiome influences response to immunotherapy and development of colitis. Microbiome with different profiles are also associated with multiple diseases, including gastrointestinal (GI) or non-GI auto-immune pathologies. Little is known about the relationship between the microbiome composition or fecal calprotectin (fCal) and the development of non-colitis immune-related adverse events (irAEs) during treatment with IO combinations.

Autoimmune conditions and irAEs from immune checkpoint inhibitors (ICI) drugs both involve loss of tolerance to endogenous antigens and produce similar clinical presentations. ICI can increase humoral response. However, to date there is no evidence that autoimmune panels are correlated with the development of irAEs during IO combination therapy.

These findings suggest that analyzing the microbiome and autoimmune panels of patients treated with IO combinations at multiple time-points may be feasible. In addition, baseline, early shift and changes in microbiome and autoimmune panels at time of a serious irAE may be correlated with the development of serious irAEs and may change with appropriate immunosuppressive regimens.

We hypothesize that analysing the microbiome and autoimmune panels of patients treated with immunooncology (IO) combinations at multiple time-points is feasible. Additionally, we hypothesize that baseline, early shift and changes in microbiome and autoimmune panels at time of a serious immune-related adverse event (irAE) is correlated with the development of serious irAEs and will change with appropriate immunosuppressive regimens.

Inclusion Criteria:

1. Signed written and voluntary informed consent.
2. Patient must be willing and able to provide collection for blood and stool specimen analysis at the pre-specified time-points.
3. Age > 18 years, male or female.
4. Patient must be diagnosed with any advanced solid tumor deemed incurable and to be treated at Princess Margaret Cancer Centre.
5. Patients must be eligible to treatment with an IO combination.

Exclusion Criteria:

1. Any conditions that in the opinion of the Investigator would interfere with patient safety, or evaluation of the collected specimen and interpretation of study result.
2. History of autoimmune disease with a flare episode within one year before study screening.

Advanced solid tumor patients receiving immunooncology combinations