Type 1 Diabetes MellitusPROSPERNCT07585994
Effect of 4 Weeks of Oral Probiotic Desulfovibrio Piger Supplementation on Immunological and Metabolic Parameters in Individuals With Longstanding Type 1 Diabetes
A study testing Probiotic dietary supplement in people with Type 1 Diabetes Mellitus, run by Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA) at 2 sites in Netherlands.
Trial summary
The goal is to establish the effect of oral probiotic Desulfovibrio piger (D. piger) supplementation on immunological and metabolic parameters in individuals with longstanding type 1 diabetes with residual beta cell function. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Type 1 Diabetes Mellitus
- What is being tested?
- Probiotic dietary supplement
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 20 participants
- Where
- 2 sitesNetherlands
- Study dates
- May 2026to May 2028
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Males or females, age >18 years
- A diagnosis of type 1 diabetes, with duration of more than 5 years, with minimally one of antiGAD65, IA2, ZnT8 autoantibodies present assessed at diagnosis or routine visits at Diabeter Centrum.
- Evidence of remaining residual beta cell function with detectable UCPCR (more than 0.01 nmol/mmol C-peptide/creatinine ratio) and or fasting plasma C-peptide more than 0.2 mmol/L.
- BMI 18-30 kg/m2
Who cannot join
- Use of antibiotics or proton-pump inhibitors within the last three months before screening or during study period
- Use of other probiotic supplementation within the last month before screening or during study period
- A history of cholecystectomy
- Overt untreated gastrointestinal disease, inflammatory bowel disease or abnormal bowel habits
- Absence of a large bowel (ie colostomy)
- Evidence for comprised immunity (HIV infection, chemotherapy, other autoimmune diseases, systemic anti-inflammatory therapy)
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- History of cardiovascular disaeses (CVD) events
- Hepatic enzymes>2.5 higher than the upper limit of normal range, determined during MARVEL visits/routine visits
- Kidney failure (eGFR <15ml.min/1.73m2), dialysis, kidney transplantation,
- Inability or unwillingness to donate feces or urine.
- Smoking or illicit drug use (e.g. MDMA/amphetamine/cocaine/heroin/GHB) in the past three months or use during the study period.
- Alcohol abuse (equal or above 21 units per week)
- Inability or unwillingness to provide informed consent.
Trial locations and contacts
2 sites in 1 country. Contact the study team or a site near you to ask about taking part.
Netherlands2 sites, 2 recruiting
- Recruiting
Diabeter Centrum Amsterdam
Amsterdam, 1066 EC
Max Nieuwdorp, Prof. Dr., +31 20-5669111, m.nieuwdorp@amsterdamumc.nl
- Recruiting
Amsterdam UMC
Amsterdam, 1105 AZ
Max Nieuwdorp, Prof. Dr., +31 20-5669111, m.nieuwdorp@amsterdamumc.nl
About this study
The goal is to establish the effect of oral probiotic Desulfovibrio piger (D. piger) supplementation on immunological and metabolic parameters in individuals with longstanding type 1 diabetes with residual beta cell function. The investigators will perform a double-blind, randomized, placebo-controlled trial in 2x10 participants to measure effects of D. piger on parameters of systemic and intestinal inflammation and residual beta cell function.
Read the detailed description
The investigators perform a double-blind, randomized, placebo-controlled trial with two arms (10 participants per arm, total of 20 participants) in adults with longstanding type 1 diabetes with residual beta cell function. The study duration is 6 weeks, with 4 weeks of intervention in which participants will be given D. piger or placebo once daily and 2 weeks of washout period. The main study enpoints include the changes (versus baseline) in parameters of systemic/intestinal inflammation and beta cell function between the placebo and D.piger-treatment arms at the end of treatment (4 weeks). In addition, any long-lasting effects will be determined by assessing the changes in the above described markers after a 2 week washout period (6 weeks).
Secondary endpoints include glucose variability (continuous glucose monitoring, CGM), fecal microbiome composition (including strain engraftment of D. piger, plasma metabolites), immune cell phenotype and frequency and validated questionnaires (gastro-intestinal complaints) at these three timepoints (0,4,6 weeks).
- Conditions
- Type 1 Diabetes Mellitus
- Being tested
- Probiotic dietary supplement, Placebo
- Keywords
- type 1 diabetes mellitus, gut microbiome, probiotics, immunological parameters, residual beta cell function
- Medical subject headings
- Diabetes Mellitus, Type 1
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Probiotic dietary supplementDietary supplement
Probiotic bacteria D. piger (10^9 colony forming units (CFU) in 10ml PBS containing 10% glycerol and 10% maltodextrin)
PlaceboDietary supplement
Placebo (10ml PBS containing 10% glycerol and 10% maltodextrin)
| Study group | Role | What they receive |
|---|---|---|
| Probiotic Desulfovibrio piger | Experimental | Probiotic bacteria D. piger (10^9 colony forming units (CFU) in 10ml PBS containing 10% glycerol and 10% maltodextrin) Receives: Dietary Supplement: Probiotic dietary supplement |
| Placebo | Placebo comparator | placebo (10ml PBS containing 10% glycerol and 10% maltodextrin) Receives: Dietary Supplement: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Parameters of systemic and intestinal inflammation
systemic inflammation determined by measuring plasma CRP, and proinflammatory cytokines (IFNgamma, IFN alpha, TNFalpha)
intestinal inflammation assessed by LB, iFABP, zonulin in plasma
Measured: From start treatment to the end of treatment at 4 weeks and washout at 6 weeks.
Residual beta cell function
Assessed by C peptide AUC during mixed meal tolerance test and/or post meal urine C-peptide/creatinine ratio levels.
Measured: From start treatment to the end of treatment at 4 weeks and washout at 6 weeks.
Secondary outcomes (4)
Glucose variability
percentage time in euglycemic range, time above range, time below range and glucose variability measured by continuous glucose monitoring (CGM)
Measured: From start treatment to the end of treatment at 4 weeks and washout at 6 weeks.
Immune cell phenotypes and frequency
Immunophenotyping by flow cytometry of PBMC (peripheral blood mononuclear cells) to determine frequency of T cell subsets with activation/exhaustion marker expression
Measured: From start treatment to the end of treatment at 4 weeks and washout at 6 weeks.
Fecal microbiome composition and strain engraftment
using 16s rRNA sequencing, primer-specific quantitative PCR for D. piger detection in feces and plasma metabolites
Measured: From start treatment to the end of treatment at 4 weeks and washout at 6 weeks.
Gastrointestinal Symptom Rating Scale (GSRS)
Questionnaire. The minimum and maximum score are 15 and 105 points respectively, and a higher score in the scale reflects more gastro-intestinal complaints.
Measured: From start treatment to the end of treatment at 4 weeks and washout at 6 weeks.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted14 May 2026
- Study startMay 2026 (estimated)
- Primary completionMay 2028 (estimated)
- Study completionMay 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Type 1 Diabetes MellitusStudies of the same condition, open and under way.
- More trials run by Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA)The sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- 2x10 participants will be randomly allocated to probiotic D. piger or placebo once daily for 4 weeks.
- Masking
- Triple blind
- Who is masked
- Participant, Care provider, Investigator
- Enrolment
- 20 participants (estimated)
Sponsor and investigators
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Max Nieuwdorp, Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA)
- Investigators
- Max Nieuwdorp, Prof. Dr., Principal investigator, Amsterdam UMC
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07585994
- Sponsor's protocol ID
- 2025.1139
- Acronym
- PROSPER
- Status last verified
- May 2026
- First submitted
- 5 May 2026
- Last updated
- 14 May 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 14 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Effect of 4 Weeks of Oral Probiotic Desulfovibrio Piger Supplementation on Immunological and Metabolic Parameters in Individuals With Longstanding Type 1 Diabetes
- ClinicalTrials.gov ID
- NCT07585994
- Acronym / sponsor ID
- PROSPER / 2025.1139
- Conditions
- Type 1 Diabetes Mellitus
- Keywords
- type 1 diabetes mellitus, gut microbiome, probiotics, immunological parameters, residual beta cell function
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 20 participants (estimated)
- Lead sponsor
- Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA)University, hospital or other
- Study start
- May 2026 (estimated)
- Primary completion
- May 2028 (estimated)
- Study completion
- May 2028 (estimated)
- First posted
- 14 May 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal is to establish the effect of oral probiotic Desulfovibrio piger (D. piger) supplementation on immunological and metabolic parameters in individuals with longstanding type 1 diabetes with residual beta cell function. The investigators will perform a double-blind, randomized, placebo-controlled trial in 2x10 participants to measure effects of D. piger on parameters of systemic and intestinal inflammation and residual beta cell function.
Detailed description
The investigators perform a double-blind, randomized, placebo-controlled trial with two arms (10 participants per arm, total of 20 participants) in adults with longstanding type 1 diabetes with residual beta cell function. The study duration is 6 weeks, with 4 weeks of intervention in which participants will be given D. piger or placebo once daily and 2 weeks of washout period. The main study enpoints include the changes (versus baseline) in parameters of systemic/intestinal inflammation and beta cell function between the placebo and D.piger-treatment arms at the end of treatment (4 weeks). In addition, any long-lasting effects will be determined by assessing the changes in the above described markers after a 2 week washout period (6 weeks).
Secondary endpoints include glucose variability (continuous glucose monitoring, CGM), fecal microbiome composition (including strain engraftment of D. piger, plasma metabolites), immune cell phenotype and frequency and validated questionnaires (gastro-intestinal complaints) at these three timepoints (0,4,6 weeks).
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind (participant, care provider, investigator)
- Number of arms
- 2
- Model description
- 2x10 participants will be randomly allocated to probiotic D. piger or placebo once daily for 4 weeks.
| Arm | Type | Receives |
|---|---|---|
| Probiotic Desulfovibrio piger | Experimental | Dietary Supplement: Probiotic dietary supplementProbiotic bacteria D. piger (10^9 colony forming units (CFU) in 10ml PBS containing 10% glycerol and 10% maltodextrin) |
| Placebo | Placebo comparator | Dietary Supplement: Placeboplacebo (10ml PBS containing 10% glycerol and 10% maltodextrin) |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Males or females, age >18 years
- A diagnosis of type 1 diabetes, with duration of more than 5 years, with minimally one of antiGAD65, IA2, ZnT8 autoantibodies present assessed at diagnosis or routine visits at Diabeter Centrum.
- Evidence of remaining residual beta cell function with detectable UCPCR (more than 0.01 nmol/mmol C-peptide/creatinine ratio) and or fasting plasma C-peptide more than 0.2 mmol/L.
- BMI 18-30 kg/m2
Key exclusion criteria (13 listed)
- Use of antibiotics or proton-pump inhibitors within the last three months before screening or during study period
- Use of other probiotic supplementation within the last month before screening or during study period
- A history of cholecystectomy
- Overt untreated gastrointestinal disease, inflammatory bowel disease or abnormal bowel habits
- Absence of a large bowel (ie colostomy)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Probiotic dietary supplementProbiotic bacteria D. piger (10^9 colony forming units (CFU) in 10ml PBS containing 10% glycerol and 10% maltodextrin) | Dietary supplement | Probiotic Desulfovibrio piger |
| PlaceboPlacebo (10ml PBS containing 10% glycerol and 10% maltodextrin) | Dietary supplement | Placebo |
Primary outcome
Parameters of systemic and intestinal inflammation
Time frame: From start treatment to the end of treatment at 4 weeks and washout at 6 weeks.
systemic inflammation determined by measuring plasma CRP, and proinflammatory cytokines (IFNgamma, IFN alpha, TNFalpha) intestinal inflammation assessed by LB, iFABP, zonulin in plasma
Residual beta cell function
Time frame: From start treatment to the end of treatment at 4 weeks and washout at 6 weeks.
Assessed by C peptide AUC during mixed meal tolerance test and/or post meal urine C-peptide/creatinine ratio levels.
4 secondary outcomes
Glucose variability
Time frame: From start treatment to the end of treatment at 4 weeks and washout at 6 weeks.
Immune cell phenotypes and frequency
Time frame: From start treatment to the end of treatment at 4 weeks and washout at 6 weeks.
Fecal microbiome composition and strain engraftment
Time frame: From start treatment to the end of treatment at 4 weeks and washout at 6 weeks.
Gastrointestinal Symptom Rating Scale (GSRS)
Time frame: From start treatment to the end of treatment at 4 weeks and washout at 6 weeks.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 14 May 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Max Nieuwdorp, Prof. Dr. principal investigator
Amsterdam UMC
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Probiotic dietary supplement in people with Type 1 Diabetes Mellitus, run by Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA) at 2 sites in Netherlands.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 13 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 14 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in Netherlands. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Max Nieuwdorp, Prof. Dr. (+31 20-5669111, m.nieuwdorp@amsterdamumc.nl), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Parameters of systemic and intestinal inflammation (time frame: From start treatment to the end of treatment at 4 weeks and washout at 6 weeks.). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 14 May 2026.