T2DMNCT06942195
Effects of Calcium on Gut Functions and Blood Glucose in Humans With Type 2 Diabetes
A study testing Ca-1000 and Ca-500 in people with T2DM, run by University of Adelaide at 1 site in Australia.
Trial summary
The intervention in this study consists of a 75-min intraduodenal infusion of an isotonic solution containing either of calcium chloride (CaCl2) or control (saline). Participants enrolled into the study will receive, in randomised, double-blind fashion (i) Saline (control), (ii) 500 mg CaCl2, or (iii) 1000 mg CaCl2 in… Read more about this study
- Who is it for?
- Ages 18 to 70 years, men only
- Conditions the study is for
- T2DM
- What is being tested?
- Ca-1000 and Ca-500
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 8 participants
- Where
- 1 siteAustralia
- Study dates
- 22 May 2025to 28 Apr 2026
- 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 to 70 years
- Men only
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Males with type 2 diabetes mellitus (T2DM). Diagnosis of T2DM will be based on WHO criteria. Only males will be included to avoid the confounding effects of the menstrual cycle on gastric emptying.
- BMI: 28-38 kg/m².
- HbA1c >=6.5 - <=7.9% at screening.
- Blood glucose medications will be required to be withheld for 48 hours prior to each study day.
- Weight-stable (i.e. <5% fluctuation) at study entry, which will be ascertained by a stable body weight in the preceding 3 months.
Who cannot join
- Significant GI symptoms, or history of GI disease or surgery
- Current gallbladder or pancreatic disease
- Cardiovascular or respiratory diseases
- Any other illnesses (except type 2 diabetes) as assessed by the investigator - (including chronic illnesses not explicitly listed above)
- Use of prescribed or non-prescribed medications (including vitamins and herbal supplements) which may affect energy metabolism, GI function, bodyweight or appetite (e.g. domperidone, cisapride, anticholinergic drugs (e.g. atropine), metoclopramide, erythromycin, hyoscine, orlistat, green tea extracts, Astragalus, St Johns Wort etc.)
- Lactose intolerance/other food allergy(ies)
Show all 18Show fewer
- Individuals with low ferritin levels (<30 ng/mL), or who have donated blood in the 12 weeks prior to taking part in the study
- High performance athletes
- Current intake of > 2 standard drinks on > 5 days per week (>140g/week)
- Current smokers of tobacco (cigarettes, cigars, pipes, sheesha, chewing, vaping etc.)
- Current use of recreational drugs, e.g. marijuana
- Current intake of any illicit substance
- Vegetarians
- Inability to tolerate nasoduodenal tube
- Inability to comprehend study protocol
- HbA1c <6% or >7.9%
- Estimated glomerular filtration rate <45 ml/min
- Any patient whose medication cannot be withheld for 48 hours for medical reasons
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Australia1 site, 1 recruiting
- Recruiting
Clinical Research Facility, Adelaide Health and Medical Sciences Building
Adelaide, South Australia, 5005
Parisa Rouhani, MsC, parisa.rouhani@adelaide.edu.au
About this study
Official title: Effects of Intraduodenal Calcium on Plasma Glucose, Glucoregulatory Hormones and Gastric Emptying in Response to a Mixed-nutrient Drink in Humans With Type 2 Diabetes
The intervention in this study consists of a 75-min intraduodenal infusion of an isotonic solution containing either of calcium chloride (CaCl2) or control (saline).
Participants enrolled into the study will receive, in randomised, double-blind fashion (i) Saline (control), (ii) 500 mg CaCl2, or (iii) 1000 mg CaCl2 in three separate sessions, each of which will be separated by at least 4 (and up to 10) days. Each study session will be 4-6 hours. Studies will be carried out in the Clinical Research Facility of the Adelaide Medical School, the University of Adelaide, by staff and students trained in the required techniques.
Read the detailed description
Each participant will be required to consume a standardised dinner meal (beef lasagne; total energy content: 602 kcal; McCain Food, Wendouree, Victoria, Australia) on the night before each visit by 7 pm. After fasting overnight for ~ 13.5 hours and refraining from exercise and alcohol during the previous 24 hours, the participant will arrive in the laboratory at 8.30 am. After confirming adherence to the study requirements, vital signs ( blood pressure, heart rate and body temperature) will be measured to establish baseline values for safety, and they will be monitored throughout the study. Then, a manometric catheter will be inserted through an anaesthetised nostril and allowed to pass through the stomach and into the duodenum by peristalsis. The infusion port will be positioned ~ 14 cm distal to the pylorus. The correct positioning of the catheter will be monitored continuously by measurement of the transmucosal potential difference in the stomach (~ -40 mV) and the duodenum (~ 0 mV). Once the catheter has been positioned correctly, an intravenous cannula will be placed into a forearm vein for regular blood sampling. At time = -30 minute, a baseline blood sample (7 ml), visual analogue scale (VAS) questionnaire to assess gastrointestinal (GI) symptoms, and breath sample to assess gastric emptying will be collected. Then the infusion of one of the study treatments, i.e. i) saline, ii) 500 mg CaCl2 or iii) 1000 mg CaCl2), will commence and continue for 75 minutes (times = -30 to 45 minutes). At time = -1 minute, participants will consume, within 1 minute, a mixed-nutrient drink (350 mL, containing 500 kcal, 74 g carbohydrates) labelled with 100 mg 13C-acetate for measurement of gastric emptying by non-invasive breath sampling at regular intervals, for subsequent analysis of 13CO2 levels. Blood samples for the measurement of plasma glucose and hormone concentrations, and VAS questionnaires, will be collected before and after the mixed-nutrient drink. At time = 240 minute, after collecting final blood and breath samples and VAS questionnaire, the intravenous cannula will be removed and the participant will be served a light lunch, after which they will be allowed to leave the laboratory. A total of 98 mL of blood (14 sampling time points, 7 mL each) will be taken on each study day (study total of 310 mL, including screening and glucose tolerance test samples).
- Conditions
- T2DM
- Being tested
- Ca-1000, Ca-500, Control
- Keywords
- Intraduodenal, Calcium, Gastric emptying, Glucoregulatory hormones, Plasma glucose, Human
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Ca-1000Other
Calcium, an essential mineral and a key component of dairy, is a regular part of our daily diet. Recent studies have shown that calcium, at doses of 1000 mg, stimulates gut hormones and motility, will be 'higher dose' in this condition.
Ca-500Other
Calcium, an essential mineral and a key component of dairy, is a regular part of our daily diet. Recent studies have shown that calcium, at doses of 500 mg, stimulates gut function. In this condition, it will be considered 'lower dose.'
ControlOther
Saline (an isotonic solution containing 2.8 g of sodium chloride (NaCl), dissolved in 225 mL of distilled water).
| Study group | Role | What they receive |
|---|---|---|
| Ca-1000 | Active comparator | In this arm, participants will receive a 75-minute intraduodenal infusion of an isotonic solution containing 3.68 g of calcium chloride dihydrate (CaCl₂·2H₂O), dissolved in 225 mL of distilled water. Receives: Other: Ca-1000 |
| Ca-500 | Active comparator | In this arm, participants will receive a 75-minute intraduodenal infusion of an isotonic solution containing 1.84 g of calcium chloride dihydrate (CaCl₂·2H₂O), dissolved in 225 mL of distilled water. Additionally, 1.2 g of sodium chloride (NaCl) will be added to ensure the solution is isosmotic (300 mOsm). Receives: Other: Ca-500 |
| Control | Placebo comparator | In this arm, participants will receive a 75-minute intraduodenal infusion of saline (an isotonic solution containing 2.8 g of sodium chloride (NaCl), dissolved in 225 mL of distilled water). Receives: Other: Control |
What is being measured
The primary outcome is the main question the study is designed to answer.
Plasma glucose concentrations
Plasma glucose concentrations (mmol/L) will be assessed using glucose oxidase method.
Measured: Blood samples will be collected over 4.5 hours: at baseline (time = -30 minutes), then at regular intervals before and after drink administration (times = -25, -15, 0, 10, 20, 30, 45, 60, 75, 90, 120, 180, 240 minutes).
Secondary outcomes (3)
Gastric emptying
13C-acetate breath test, measuring 13CO2 concentrations in end-expiratory breath samples.
Measured: Breath samples will be collected in sealed tubes over 4.5 hours: at baseline (time = -30 minutes) (prior to treatment administration), every 5 minutes after the drink (times = 0 to 60 minutes), then every 10 minutes until 240 minutes post-drink.
Plasma concentrations of glucoregulatory hormones e.g. glucagon-like peptide (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), C-peptide, glucagon, insulin and cholecystokinin (CCK)
Plasma concentration of hormones e.g. GLP-1, GIP and CCK (pmol/L) will be determined using radioimmunoassays, and plasma C-peptide, glucagon and insulin concentrations (pmol/L) will be measured using ELISA immunoassays.
Measured: Blood samples will be collected over 4.5 hours: at baseline (time = -30 minutes), then at regular intervals before and after the drink (times = -25, -15, 0, 10, 20, 30, 45, 60, 75, 90, 120, 180, 240 minutes).
GI symptoms (nausea and bloating) will be assessed as a composite secondary outcome.
These will be measured using 100mm VAS questionnaire.
Measured: Visual Analogue questionnaires will be collected over 4.5 hours: at baseline (time = -30 minutes), at regular intervals before and after the drink (times = -25, -15, 0, 20, 30, 45 minutes), then every 10 minutes until 240 minutes.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted24 Apr 2025
- Study start22 May 2025
- Primary completion28 Mar 2026 (estimated)
- Study completion28 Apr 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for T2DMStudies of the same condition, open and under way.
- 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
- Other
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Triple blind
- Who is masked
- Participant, Investigator, Outcomes assessor
- Enrolment
- 8 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of Adelaide
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Christine Feinle-Bisset, University of Adelaide
- Investigators
- Prof Christine Feinle-Bisset, Principal investigator, Adelaide Medical School University of Adelaide Level 5 Adelaide Health and Medical Sciences Building, Cnr George St and North Tce, Adelaide, SA 5005
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06942195
- Sponsor's protocol ID
- 13243-1
- Status last verified
- Apr 2025
- First submitted
- 8 Apr 2025
- Last updated
- 26 Dec 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: The datasets generated during and/or analysed during the current study are not publicly available due to the ethical statement and informed consent that require privacy of data.
Study at a glance
From the registry record, last updated by the sponsor on 26 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Effects of Intraduodenal Calcium on Plasma Glucose, Glucoregulatory Hormones and Gastric Emptying in Response to a Mixed-nutrient Drink in Humans With Type 2 Diabetes
- ClinicalTrials.gov ID
- NCT06942195
- Acronym / sponsor ID
- 13243-1
- Conditions
- T2DM
- Keywords
- Intraduodenal, Calcium, Gastric emptying, Glucoregulatory hormones, Plasma glucose, Human
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 8 participants (estimated)
- Lead sponsor
- University of AdelaideUniversity, hospital or other
- Study start
- 22 May 2025 (actual)
- Primary completion
- 28 Mar 2026 (estimated)
- Study completion
- 28 Apr 2026 (estimated)
- First posted
- 24 Apr 2025 (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 intervention in this study consists of a 75-min intraduodenal infusion of an isotonic solution containing either of calcium chloride (CaCl2) or control (saline).
Participants enrolled into the study will receive, in randomised, double-blind fashion (i) Saline (control), (ii) 500 mg CaCl2, or (iii) 1000 mg CaCl2 in three separate sessions, each of which will be separated by at least 4 (and up to 10) days. Each study session will be 4-6 hours. Studies will be carried out in the Clinical Research Facility of the Adelaide Medical School, the University of Adelaide, by staff and students trained in the required techniques.
Detailed description
Each participant will be required to consume a standardised dinner meal (beef lasagne; total energy content: 602 kcal; McCain Food, Wendouree, Victoria, Australia) on the night before each visit by 7 pm. After fasting overnight for ~ 13.5 hours and refraining from exercise and alcohol during the previous 24 hours, the participant will arrive in the laboratory at 8.30 am. After confirming adherence to the study requirements, vital signs ( blood pressure, heart rate and body temperature) will be measured to establish baseline values for safety, and they will be monitored throughout the study. Then, a manometric catheter will be inserted through an anaesthetised nostril and allowed to pass through the stomach and into the duodenum by peristalsis. The infusion port will be positioned ~ 14 cm distal to the pylorus. The correct positioning of the catheter will be monitored continuously by measurement of the transmucosal potential difference in the stomach (~ -40 mV) and the duodenum (~ 0 mV). Once the catheter has been positioned correctly, an intravenous cannula will be placed into a forearm vein for regular blood sampling. At time = -30 minute, a baseline blood sample (7 ml), visual analogue scale (VAS) questionnaire to assess gastrointestinal (GI) symptoms, and breath sample to assess gastric emptying will be collected. Then the infusion of one of the study treatments, i.e. i) saline, ii) 500 mg CaCl2 or iii) 1000 mg CaCl2), will commence and continue for 75 minutes (times = -30 to 45 minutes). At time = -1 minute, participants will consume, within 1 minute, a mixed-nutrient drink (350 mL, containing 500 kcal, 74 g carbohydrates) labelled with 100 mg 13C-acetate for measurement of gastric emptying by non-invasive breath sampling at regular intervals, for subsequent analysis of 13CO2 levels. Blood samples for the measurement of plasma glucose and hormone concentrations, and VAS questionnaires, will be collected before and after the mixed-nutrient drink. At time = 240 minute, after collecting final blood and breath samples and VAS questionnaire, the intravenous cannula will be removed and the participant will be served a light lunch, after which they will be allowed to leave the laboratory. A total of 98 mL of blood (14 sampling time points, 7 mL each) will be taken on each study day (study total of 310 mL, including screening and glucose tolerance test samples).
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Triple blind (participant, investigator, outcomes assessor)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Ca-1000 | Active comparator | Other: Ca-1000In this arm, participants will receive a 75-minute intraduodenal infusion of an isotonic solution containing 3.68 g of calcium chloride dihydrate (CaCl₂·2H₂O), dissolved in 225 mL of distilled water. |
| Ca-500 | Active comparator | Other: Ca-500In this arm, participants will receive a 75-minute intraduodenal infusion of an isotonic solution containing 1.84 g of calcium chloride dihydrate (CaCl₂·2H₂O), dissolved in 225 mL of distilled water. Additionally, 1.2 g of sodium chloride (NaCl) will be added to ensure the solution is isosmotic (300 mOsm). |
| Control | Placebo comparator | Other: ControlIn this arm, participants will receive a 75-minute intraduodenal infusion of saline (an isotonic solution containing 2.8 g of sodium chloride (NaCl), dissolved in 225 mL of distilled water). |
Who may qualify
- Ages
- 18 to 70 years
- Sex
- Male only
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- Males with type 2 diabetes mellitus (T2DM). Diagnosis of T2DM will be based on WHO criteria. Only males will be included to avoid the confounding effects of the menstrual cycle on gastric emptying.
- BMI: 28-38 kg/m².
- HbA1c >=6.5 - <=7.9% at screening.
- Blood glucose medications will be required to be withheld for 48 hours prior to each study day.
- Weight-stable (i.e. <5% fluctuation) at study entry, which will be ascertained by a stable body weight in the preceding 3 months.
Key exclusion criteria (18 listed)
- Significant GI symptoms, or history of GI disease or surgery
- Current gallbladder or pancreatic disease
- Cardiovascular or respiratory diseases
- Any other illnesses (except type 2 diabetes) as assessed by the investigator - (including chronic illnesses not explicitly listed above)
- Use of prescribed or non-prescribed medications (including vitamins and herbal supplements) which may affect energy metabolism, GI function, bodyweight or appetite (e.g. domperidone, cisapride, anticholinergic drugs (e.g. atropine), metoclopramide, erythromycin, hyoscine, orlistat, green tea extracts, Astragalus, St Johns Wort etc.)
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 |
|---|---|---|
| Ca-1000Calcium, an essential mineral and a key component of dairy, is a regular part of our daily diet. Recent studies have shown that calcium, at doses of 1000 mg, stimulates gut hormones and motility, will be 'higher dose' in this condition. | Other | Ca-1000 |
| Ca-500Calcium, an essential mineral and a key component of dairy, is a regular part of our daily diet. Recent studies have shown that calcium, at doses of 500 mg, stimulates gut function. In this condition, it will be considered 'lower dose.' | Other | Ca-500 |
| ControlSaline (an isotonic solution containing 2.8 g of sodium chloride (NaCl), dissolved in 225 mL of distilled water). | Other | Control |
Primary outcome
Plasma glucose concentrations
Time frame: Blood samples will be collected over 4.5 hours: at baseline (time = -30 minutes), then at regular intervals before and after drink administration (times = -25, -15, 0, 10, 20, 30, 45, 60, 75, 90, 120, 180, 240 minutes).
Plasma glucose concentrations (mmol/L) will be assessed using glucose oxidase method.
3 secondary outcomes
Gastric emptying
Time frame: Breath samples will be collected in sealed tubes over 4.5 hours: at baseline (time = -30 minutes) (prior to treatment administration), every 5 minutes after the drink (times = 0 to 60 minutes), then every 10 minutes until 240 minutes post-drink.
Plasma concentrations of glucoregulatory hormones e.g. glucagon-like peptide (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), C-peptide, glucagon, insulin and cholecystokinin (CCK)
Time frame: Blood samples will be collected over 4.5 hours: at baseline (time = -30 minutes), then at regular intervals before and after the drink (times = -25, -15, 0, 10, 20, 30, 45, 60, 75, 90, 120, 180, 240 minutes).
GI symptoms (nausea and bloating) will be assessed as a composite secondary outcome.
Time frame: Visual Analogue questionnaires will be collected over 4.5 hours: at baseline (time = -30 minutes), at regular intervals before and after the drink (times = -25, -15, 0, 20, 30, 45 minutes), then every 10 minutes until 240 minutes.
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 26 Dec 2025.
- Individual participant dataSharing planned: No. The datasets generated during and/or analysed during the current study are not publicly available due to the ethical statement and informed consent that require privacy of data.
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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.
Prof Christine Feinle-Bisset principal investigator
Adelaide Medical School University of Adelaide Level 5 Adelaide Health and Medical Sciences Building, Cnr George St and North Tce, Adelaide, SA 5005
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Ca-1000 and Ca-500 in people with T2DM, run by University of Adelaide at 1 site in Australia.
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 5 inclusion and 18 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 26 Dec 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Australia. 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 Prof Christine Feinle-Bisset (+61 8 8313 6053, christine.feinle@adelaide.edu.au), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Plasma glucose concentrations (time frame: Blood samples will be collected over 4.5 hours: at baseline (time = -30 minutes), then at regular intervals before and after drink administration (times = -25, -15, 0, 10, 20, 30, 45, 60, 75, 90, 120, 180, 240 minutes).). 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 26 Dec 2025.