Administration of Oral Probiotic Streptococcus Salivarius K12

NCT07757360 | Active Not Recruiting

• 1 other identifier: BASEC-Nr. 2025-02383
• Study Type: interventional
• Target: 12
• Locations: 1 country
• Sites: 1

Brief Summary

The clinical trial is investigating the oral administration of probiotic Streptococcus salivarius K12 in the form of lozenges in healthy adults. The main outcome measures are:

• Potential for Streptococcus salivarius K12 to colonise the oral cavity
• Effect on other bacteria and Candida albicans in the oral cavity
• Possible anti-inflammatory effect Participants will:
• Take one lozenge containing Streptococcus salivarius K12 daily for 4 weeks
• Attend 3 dental check-ups (before starting the probiotic treatment, and after 4 and 8 weeks)
• Collect their own saliva samples in accordance with a sampling schedule

Conditions

Oral Health

Outcome Measures

Primary Outcomes (3)

• Impact of Streptococcus salivarius K12 on oral colonization

  Quantitative PCR (qPCR) for Streptococcus salivarius and BLIS-containing plasmid counts in saliva samples

  Baseline, intervention, and washout samples are collected according to a sampling schedule for 8 weeks.

• Impact of Streptococcus salivarius K12 on oral colonization

  Microbiome analysis of dental plaque samples (Bacteria, 16S rRNA gene sequencing)

  Three dental plaque samples are analysed: baseline, intervention (after 4 weeks), and washout (after 8 weeks)

• Impact of Streptococcus salivarius K12 on oral colonization

  Determination of Candida albicans load by culture from saliva samples

  Three saliva samples are analysed: baseline, intervention (after 4 weeks), and washout (after 8 weeks)

Secondary Outcomes (1)

• Impact of Streptococcus salivarius K12 on salivary immune markers

  Baseline, intervention, and washout samples (saliva) are collected according to a sampling schedule for 8 weeks.

Study Arms (1)

BIOTICS-O

EXPERIMENTAL

The study is designed with before-and-after controls.

Dietary Supplement: Probiotic

Interventions

Probiotic DIETARY_SUPPLEMENT

The intervention consists of daily consumption of 1 lozenge BIOTICS-O for 4 weeks. BIOTICS-O are probiotic lozenges from the manufacturer Burgerstein Vitamine. They contain viable Streptococcus salivarius K12 (BLIS® K12, ATCC BAA-1024), 1 billion colony-forming units (CFU) per lozenge. BIOTICS-O is a dietary supplement available over the counter in Swiss pharmacies.

Also known as: Streptococcus salivarius K12

BIOTICS-O

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Healthy volunteers
• Adults (\> 18 years)
• no caries or periodontal disease

You may not qualify if:

• Within the last 4 weeks before the trial, intake of...
• anti-inflammatory drugs
• antimicrobial substances
• probiotics

Sponsors & Collaborators

• University of Zurich: lead

Study Sites (1)

Center for Dental Medicine

Zurich, Canton of Zurich, 8032, Switzerland

Location

MeSH Terms

Interventions

Probiotics

Intervention Hierarchy (Ancestors)

Dietary Supplements; Food; Diet, Food, and Nutrition; Physiological Phenomena; Food and Beverages

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: June 10, 2026
• First Posted: August 11, 2026
• Study Start: May 6, 2026
• Primary Completion: August 1, 2026
• Study Completion: August 1, 2026
• Last Updated: August 11, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will not share

Locations

CH (1)