Administration of Oral Probiotic Streptococcus Salivarius K12

NCT07757360 — Not applicable, Active not recruiting, 12 participants, University of Zurich

ClinicalTrials Daily · Areas · Conditions · Drugs · Sponsors ·

Administration of Oral Probiotic Streptococcus Salivarius K12: Oral Colonization, Impact on Oral Microbiome and Inflammatory Markers

Registry	NCT07757360
Status	Active not recruiting
Phase	Not applicable
Study type	Interventional; na, single group, masking: none, treatment
Enrollment	12 (Actual)
Sponsor	University of Zurich (Other)
Conditions	Oral Health
Interventions	Probiotic (Dietary supplement)
Dates	start 2026-05-06, primary completion 2026-08-01 (estimated), completion 2026-08-01 (estimated), first posted 2026-08-11, last updated 2026-08-11
Locations	1 site in Switzerland

-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

Expand all sections · Collapse all

+Arms and interventions

Arm	Type	Interventions	Description
BIOTICS-O	Experimental	Dietary Supplement: Probiotic	The study is designed with before-and-after controls.

Probiotic (Dietary supplement), also known as Streptococcus salivarius K12: 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.

+Outcome measures

Primary outcomes

Impact of Streptococcus salivarius K12 on oral colonization [Baseline, intervention, and washout samples are collected according to a sampling schedule for 8 weeks.]: Quantitative PCR (qPCR) for Streptococcus salivarius and BLIS-containing plasmid counts in saliva samples
Impact of Streptococcus salivarius K12 on oral colonization [Three dental plaque samples are analysed: baseline, intervention (after 4 weeks), and washout (after 8 weeks)]: Microbiome analysis of dental plaque samples (Bacteria, 16S rRNA gene sequencing)
Impact of Streptococcus salivarius K12 on oral colonization [Three saliva samples are analysed: baseline, intervention (after 4 weeks), and washout (after 8 weeks)]: Determination of Candida albicans load by culture from saliva samples

Secondary outcomes

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.]: Determination of immune marker concentration (IL-1 beta, IL-6, IL-10, MMP-8, and TNF alpha) in saliva using the Luminex technology

+Eligibility

Sex: All, ages: 18 Years to any, accepts healthy volunteers

Inclusion Criteria:

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

Exclusion Criteria:

Within the last 4 weeks before the trial, intake of...

* anti-inflammatory drugs
* antimicrobial substances
* probiotics

+Locations (1)

Facility	City	Country	Status
Center for Dental Medicine	Zurich, Canton of Zurich	Switzerland