Safety and Tolerability Evaluationof Phascolarcobacterium Faecium

Primary outcomes

1. Incidence of adverse events and general health status

   Time frame: 21 days

   Participants will have access to a 24-hour contact number to report any inconvenience or adverse effects. All adverse effects will be recorded throughout the intervention period and for one additional week after completion. Outcomes will be reported as the presence or absence of adverse effects.

2. Systemic safety of P. faecium intake assessed in all the clinical trial participants by biochemical markers

   Time frame: 15 days

   Complete hemogram and biochemical analysis will be permormed at baseline and after bacterum intervention and includes red blood cells, white blood cells, and assessments of lipid profile (triglycerides, total cholesterol, LDL cholesterol, HDL cholesterol, and non-HDL cholesterol), renal function (urea, creatinine, and uric acid), hepatic function (total protein, AST, and ALT), and glucose homeostasis (glucose, insulin, HbA1c, and HOMA-IR).

   All parameters will be measured using standard units commonly applied in clinical practice, and results will be compared before and after the intervention. It will be interpreted as either unchanged or altered relative to baseline values.

3. Tolerability assessment measured by stool habit

   Time frame: 15 days

   To assess the tolerability of P. faecium, participants will complete gastrointestinal symptom questionnaires before and after the intervention, capturing both weekly bowel movement frequency and stool consistency using the Bristol Stool Scale. Stool habits will be evaluated by integrating these two variables: a normal habit will be defined as 4-14 bowel movements per week together with a Bristol score of 3-5, whereas any deviation from these ranges will be classified as an altered stool habit.

4. Tolerability assessment measured by the frequency of heartburn.

   Time frame: 15 days

   Use of probiotic bacteria may occasionally elicit mild gastrointestinal discomfort, including bloating, gas or abdominal cramps. To assess the tolerability of the tested bacterium, participants will complete gastrointestinal symptom questionnaires before and after the intervention, which also capture the frequency of heartburn. Response options include: "all the time," "most of the time," "sometimes," "a few times," and "never." Changes in frequency will be compared between pre- and post-treatment assessments.

5. Tolerability assessment measured by the frequency of abdominal bloating.

   Time frame: 15 days

   Use of probiotic bacteria may occasionally elicit mild gastrointestinal discomfort, including bloating, gas or abdominal cramps. To assess the tolerability of the tested bacterium, participants will complete gastrointestinal symptom questionnaires before and after the intervention, which also capture the frequency of abdominal bloating. Response options include: "all the time," "most of the time," "sometimes," "a few times," and "never." Changes in frequency will be compared between pre- and post-treatment assessments.

6. Tolerability assessment measured by the frequency of constipation.

   Time frame: 15 days

   Use of probiotic bacteria may occasionally elicit mild gastrointestinal discomfort, including bloating, gas or abdominal cramps. To assess the tolerability of the tested bacterium, participants will complete gastrointestinal symptom questionnaires before and after the intervention, which also capture the frequency of constipation. Response options include: "all the time," "most of the time," "sometimes," "a few times," and "never." Changes in frequency will be compared between pre- and post-treatment assessments.

7. Tolerability assessment measured by the frequency of diarrhea.

   Time frame: 15 days

   Use of probiotic bacteria may occasionally elicit mild gastrointestinal discomfort, including bloating, gas or abdominal cramps. To assess the tolerability of the tested bacterium, participants will complete gastrointestinal symptom questionnaires before and after the intervention, which also capture the frequency of diarrhea. Response options include: "all the time," "most of the time," "sometimes," "a few times," and "never." Changes in frequency will be compared between pre- and post-treatment assessments.

8. Tolerability assessment measured by the frequency of nausea.

   Time frame: 15 days

   Use of probiotic bacteria may occasionally elicit mild gastrointestinal discomfort, including bloating, gas or abdominal cramps. To assess the tolerability of the tested bacterium, participants will complete gastrointestinal symptom questionnaires before and after the intervention, which also capture the frequency of nausea. Response options include: "all the time," "most of the time," "sometimes," "a few times," and "never." Changes in frequency will be compared between pre- and post-treatment assessments.

9. Tolerability assessment measured by the frequency of flatulence.

   Time frame: 15 days

   Use of probiotic bacteria may occasionally elicit mild gastrointestinal discomfort, including bloating, gas or abdominal cramps. To assess the tolerability of the tested bacterium, participants will complete gastrointestinal symptom questionnaires before and after the intervention, which also capture the frequency of flatulence. Response options include: "all the time," "most of the time," "sometimes," "a few times," and "never." Changes in frequency will be compared between pre- and post-treatment assessments.