Postprandial Amino Acid Concentrations in Healthy AdultsNCT07479173
Effects of P24 on Postprandial Aminoacidemia
A study testing Protease enzyme supplement in people with Postprandial Amino Acid Concentrations in Healthy Adults, run by Amplifye at 1 site in United States.
Trial summary
The purpose of this study is to quantify the acute effects of an acid-active protease enzyme supplement (P24) on postprandial aminoacidemia following consumption of a standardized mixed-protein meal containing both plant- and animal-derived protein sources. Read more about this study
- Who is it for?
- Ages 45 to 75 yearsHealthy volunteers can take part
- Conditions the study is for
- Postprandial Amino Acid Concentrations in Healthy Adults
- What is being tested?
- Protease enzyme supplement
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 30 participants
- Where
- 1 siteUnited States
- Study dates
- 5 Sep 2026to 15 Dec 2027
- 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 45 to 75 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Healthy adults aged 45-75 years
- BMI 18.5-35 kg/m2
- Able to provide informed consent and comply with study procedure
- Willing to consume the standardized mixed-protein test meal
Who cannot join
- BMI outside of 18.5-35 kg/m2
- Gastrointestinal disorders or malabsorption syndromes that could affect digestion/absorption (e.g., inflammatory bowel disease, celiac disease)
- Diagnosed diabetes
- Current use of medications or supplements that materially affect glucose metabolism or digestion (e.g., GLP-1 receptor agonists, chronic digestive enzyme supplementation)
- Resting blood pressure ≥ 140/90 mmHg
- Self-reported cancer within past 5 years
Show all 10Show fewer
- Known allergy or intolerance to meal components or capsule ingredients
- Self-reported anemia or other conditions that increase risk from blood draws
- Pregnancy or breastfeeding
- Current smoking or nicotine use, heavy alcohol use (defined as > 5 drinks/day or > 15 drinks/week), or other factors that in the investigator's judgment make participation unsafe
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Holt contact
United States1 site, 1 recruiting
- Recruiting
Ragle Human Nutrition Center
Davis, California, 95616
Roberta H Holt, PhD, 530-400-5952, rrholt@ucdavis.edu
About this study
Official title: Effects of an Acid-Active Protease (P24) on Postprandial Aminoacidemia Following a Standardized Mixed-Protein Burger Meal in Healthy Adults
The purpose of this study is to quantify the acute effects of an acid-active protease enzyme supplement (P24) on postprandial aminoacidemia following consumption of a standardized mixed-protein meal containing both plant- and animal-derived protein sources. Secondary objectives include evaluating the postprandial plasma peptidomic response, characterizing the postprandial hormonal responses (GLP-1, insulin, and GIP), and assessing the postprandial glucose response using standardized capillary blood glucose measurements. The study will also evaluate subjective responses including satiety and hunger and gastrointestinal symptoms.
Read the detailed description
This study is a randomized, double-blind, placebo-controlled crossover trial designed to evaluate the acute effects of an acid-active protease enzyme supplement (P24) on postprandial amino acid availability after consumption of a standardized mixed-protein meal in healthy adults. Each participant will complete two morning test visits separated by an approximately 7-day washout period and will receive P24 during one visit and placebo during the other visit in randomized order. Each participant will therefore serve as his or her own control.
The primary objective is to compare postprandial circulating total amino acid responses between the P24 and placebo conditions following the test meal. Secondary objectives are to evaluate essential amino acids, branched-chain amino acids, postprandial glucose responses, postprandial hormonal responses including GLP-1, GIP, and insulin, plasma peptide profiles, and subjective responses such as hunger, satiety, and gastrointestinal symptoms.
Visits will be conducted in the morning after an overnight fast. Pre-visit standardization will include restrictions on vigorous exercise, alcohol, nicotine, and caffeine prior to each test visit, as well as instructions to maintain similar dietary intake before each study period. At the first visit, height and weight will be measured. At each visit, participants will complete brief questionnaires related to recent diet and activity, sleep, gastrointestinal symptoms, and subjective appetite.
An indwelling intravenous catheter will be placed in a forearm vein for repeated venous blood collection. Venous blood samples will be collected at baseline and at multiple postprandial timepoints over 180 minutes following meal consumption. Capillary blood glucose will also be assessed at matched timepoints using standardized finger-prick measurements. Participants will remain on site during the postprandial observation period and will be monitored for adverse events and procedure-related symptoms.
The test meal will be a standardized mixed-protein burger meal designed to include both animal-derived and plant-derived protein sources. Meal composition, preparation, and serving procedures will be standardized across visits. Participants will consume the meal with water within a defined time window. On each study day, participants will receive either one P24 capsule or one matching placebo capsule immediately prior to the meal according to the study randomization schedule. Active and placebo products will be identical in appearance to maintain blinding.
Targeted amino acid analysis will be performed using LC-MS/MS to quantify circulating amino acid concentrations across the postprandial period. The primary endpoint will be incremental area under the curve for total amino acids over 0 to 180 minutes. Secondary amino acid outcomes will include essential amino acids, branched-chain amino acids, and selected kinetic parameters including maximum observed concentration and time to maximum concentration. Hormonal outcomes will include GLP-1, GIP, and insulin measured at prespecified timepoints. Glucose outcomes will include postprandial incremental area under the curve and related peak and variability measures based on discrete capillary sampling.
Exploratory plasma peptidomic profiling will be conducted in a subset of participants using aliquots from routine plasma samples collected during study visits, without additional blood collection. Subset selection will be performed using prespecified balancing criteria and will not be based on the magnitude or direction of observed treatment effects.
Data will be analyzed using statistical methods appropriate for a crossover design, including paired or mixed-effects approaches as appropriate for each outcome. Standardized procedures for visit conduct, sample handling, laboratory processing, and data review will be used to support data quality and protocol consistency.
- Being tested
- Protease enzyme supplement, Placebo
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Protease enzyme supplementDietary supplement
Also called P24
Participants receive one capsule containing P24, an acid-active protease enzyme preparation, prior to consumption of a standardized mixed-protein burger meal during one study visit. The intervention is administered in a randomized, double-blind, placebo-controlled crossover design and is compared with a matching placebo capsule containing microcrystalline cellulose. Postprandial responses are assessed over 180 minutes following meal consumption.
PlaceboOther
Participants receive one matching placebo capsule containing microcrystalline cellulose prior to consumption of a standardized mixed-protein burger meal during one study visit. The placebo is identical in appearance to the active capsule and is administered in a randomized, double-blind, placebo-controlled crossover design. Postprandial responses are assessed over 180 minutes following meal consumption.
| Study group | Role | What they receive |
|---|---|---|
| Protease enzyme supplement | Experimental | P24 is an acid-active protease enzyme supplement administered as one capsule prior to the standardized mixed-protein burger meal. The active product contains P24 and is compared with a matching placebo capsule in a randomized, double-blind crossover design in healthy adults Receives: Dietary Supplement: Protease enzyme supplement |
| Placebo | Placebo comparator | Matching placebo capsule containing microcrystalline cellulose, administered prior to the standardized mixed-protein burger meal. Placebo capsules are identical in appearance to the active product and are used to maintain blinding in the randomized crossover design. Receives: Other: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Postprandial total amino acid incremental area under the curve after the test meal with P24 versus placebo
Incremental area under the curve for circulating total amino acids following consumption of the standardized test meal with P24 compared with placebo.
Measured: 0 to 180 minutes after meal consumption
Secondary outcomes (4)
Postprandial essential amino acid and branched-chain amino acid responses after the test meal with P24 versus placebo
Incremental area under the curve for circulating essential amino acids and branched-chain amino acids, as well as maximum observed concentration and time to maximum concentration, following consumption of the standardized test meal with P24 compared with placebo.
Measured: 0 to180 minutes after meal consumption
Postprandial plasma hormone responses after the test meal with P24 versus placebo
Incremental area under the curve, maximum observed concentration, and time to maximum concentration for GLP-1, GIP, and insulin following consumption of the standardized test meal with P24 compared with placebo. Hormones will be measured at baseline and at 60 and 180 minutes after meal consumption.
Measured: Baseline, 60 minutes after meal consumption, and 180 minutes after meal consumption
Postprandial plasma peptide profile after the test meal with P24 versus placebo
Differential peptide abundances in plasma following consumption of the standardized test meal with P24 compared with placebo. Plasma peptide profiling will be assessed at baseline and at 60 and 180 minutes after meal consumption.
Measured: Baseline, 60 minutes after meal consumption, and 180 minutes after meal consumption
Postprandial capillary blood glucose responses after the test meal with P24 versus placebo
Incremental area under the curve, peak glucose, time to peak glucose, and variability metrics for capillary blood glucose following consumption of the standardized test meal with P24 compared with placebo.
Measured: Baseline and 30, 60, 90, 120, and 180 minutes after meal consumption
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted18 Mar 2026
- Study start5 Sep 2026
- Primary completion31 Mar 2027 (estimated)
- Study completion15 Dec 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Postprandial Amino Acid Concentrations in Healthy AdultsStudies 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
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Amplifye
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Roberta H Holt, PhD, Principal investigator, University of California, Davis
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07479173
- Sponsor's protocol ID
- 2419791
- Status last verified
- Sep 2026
- First submitted
- 11 Mar 2026
- Last updated
- 9 Sep 2026
- Results posted
- No
- Data monitoring committee
- No
- 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 9 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Effects of an Acid-Active Protease (P24) on Postprandial Aminoacidemia Following a Standardized Mixed-Protein Burger Meal in Healthy Adults
- ClinicalTrials.gov ID
- NCT07479173
- Acronym / sponsor ID
- 2419791
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- AmplifyeIndustry (pharma, biotech, devices)
- Study start
- 5 Sep 2026 (actual)
- Primary completion
- 31 Mar 2027 (estimated)
- Study completion
- 15 Dec 2027 (estimated)
- First posted
- 18 Mar 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 purpose of this study is to quantify the acute effects of an acid-active protease enzyme supplement (P24) on postprandial aminoacidemia following consumption of a standardized mixed-protein meal containing both plant- and animal-derived protein sources. Secondary objectives include evaluating the postprandial plasma peptidomic response, characterizing the postprandial hormonal responses (GLP-1, insulin, and GIP), and assessing the postprandial glucose response using standardized capillary blood glucose measurements. The study will also evaluate subjective responses including satiety and hunger and gastrointestinal symptoms.
Detailed description
This study is a randomized, double-blind, placebo-controlled crossover trial designed to evaluate the acute effects of an acid-active protease enzyme supplement (P24) on postprandial amino acid availability after consumption of a standardized mixed-protein meal in healthy adults. Each participant will complete two morning test visits separated by an approximately 7-day washout period and will receive P24 during one visit and placebo during the other visit in randomized order. Each participant will therefore serve as his or her own control.
The primary objective is to compare postprandial circulating total amino acid responses between the P24 and placebo conditions following the test meal. Secondary objectives are to evaluate essential amino acids, branched-chain amino acids, postprandial glucose responses, postprandial hormonal responses including GLP-1, GIP, and insulin, plasma peptide profiles, and subjective responses such as hunger, satiety, and gastrointestinal symptoms.
Visits will be conducted in the morning after an overnight fast. Pre-visit standardization will include restrictions on vigorous exercise, alcohol, nicotine, and caffeine prior to each test visit, as well as instructions to maintain similar dietary intake before each study period. At the first visit, height and weight will be measured. At each visit, participants will complete brief questionnaires related to recent diet and activity, sleep, gastrointestinal symptoms, and subjective appetite.
An indwelling intravenous catheter will be placed in a forearm vein for repeated venous blood collection. Venous blood samples will be collected at baseline and at multiple postprandial timepoints over 180 minutes following meal consumption. Capillary blood glucose will also be assessed at matched timepoints using standardized finger-prick measurements. Participants will remain on site during the postprandial observation period and will be monitored for adverse events and procedure-related symptoms.
The test meal will be a standardized mixed-protein burger meal designed to include both animal-derived and plant-derived protein sources. Meal composition, preparation, and serving procedures will be standardized across visits. Participants will consume the meal with water within a defined time window. On each study day, participants will receive either one P24 capsule or one matching placebo capsule immediately prior to the meal according to the study randomization schedule. Active and placebo products will be identical in appearance to maintain blinding.
Targeted amino acid analysis will be performed using LC-MS/MS to quantify circulating amino acid concentrations across the postprandial period. The primary endpoint will be incremental area under the curve for total amino acids over 0 to 180 minutes. Secondary amino acid outcomes will include essential amino acids, branched-chain amino acids, and selected kinetic parameters including maximum observed concentration and time to maximum concentration. Hormonal outcomes will include GLP-1, GIP, and insulin measured at prespecified timepoints. Glucose outcomes will include postprandial incremental area under the curve and related peak and variability measures based on discrete capillary sampling.
Exploratory plasma peptidomic profiling will be conducted in a subset of participants using aliquots from routine plasma samples collected during study visits, without additional blood collection. Subset selection will be performed using prespecified balancing criteria and will not be based on the magnitude or direction of observed treatment effects.
Data will be analyzed using statistical methods appropriate for a crossover design, including paired or mixed-effects approaches as appropriate for each outcome. Standardized procedures for visit conduct, sample handling, laboratory processing, and data review will be used to support data quality and protocol consistency.
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Double blind (participant, investigator)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Protease enzyme supplement | Experimental | Dietary Supplement: Protease enzyme supplementP24 is an acid-active protease enzyme supplement administered as one capsule prior to the standardized mixed-protein burger meal. The active product contains P24 and is compared with a matching placebo capsule in a randomized, double-blind crossover design in healthy adults |
| Placebo | Placebo comparator | Other: PlaceboMatching placebo capsule containing microcrystalline cellulose, administered prior to the standardized mixed-protein burger meal. Placebo capsules are identical in appearance to the active product and are used to maintain blinding in the randomized crossover design. |
Who may qualify
- Ages
- 45 to 75 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Healthy adults aged 45-75 years
- BMI 18.5-35 kg/m2
- Able to provide informed consent and comply with study procedure
- Willing to consume the standardized mixed-protein test meal
Key exclusion criteria (10 listed)
- BMI outside of 18.5-35 kg/m2
- Gastrointestinal disorders or malabsorption syndromes that could affect digestion/absorption (e.g., inflammatory bowel disease, celiac disease)
- Diagnosed diabetes
- Current use of medications or supplements that materially affect glucose metabolism or digestion (e.g., GLP-1 receptor agonists, chronic digestive enzyme supplementation)
- Resting blood pressure ≥ 140/90 mmHg
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 |
|---|---|---|
| Protease enzyme supplementAlso: P24Participants receive one capsule containing P24, an acid-active protease enzyme preparation, prior to consumption of a standardized mixed-protein burger meal during one study visit. The intervention is administered in a randomized, double-blind, placebo-controlled crossover design and is compared with a matching placebo capsule containing microcrystalline cellulose. Postprandial responses are assessed over 180 minutes following meal consumption. | Dietary supplement | Protease enzyme supplement |
| PlaceboParticipants receive one matching placebo capsule containing microcrystalline cellulose prior to consumption of a standardized mixed-protein burger meal during one study visit. The placebo is identical in appearance to the active capsule and is administered in a randomized, double-blind, placebo-controlled crossover design. Postprandial responses are assessed over 180 minutes following meal consumption. | Other | Placebo |
Primary outcome
Postprandial total amino acid incremental area under the curve after the test meal with P24 versus placebo
Time frame: 0 to 180 minutes after meal consumption
Incremental area under the curve for circulating total amino acids following consumption of the standardized test meal with P24 compared with placebo.
4 secondary outcomes
Postprandial essential amino acid and branched-chain amino acid responses after the test meal with P24 versus placebo
Time frame: 0 to180 minutes after meal consumption
Postprandial plasma hormone responses after the test meal with P24 versus placebo
Time frame: Baseline, 60 minutes after meal consumption, and 180 minutes after meal consumption
Postprandial plasma peptide profile after the test meal with P24 versus placebo
Time frame: Baseline, 60 minutes after meal consumption, and 180 minutes after meal consumption
Postprandial capillary blood glucose responses after the test meal with P24 versus placebo
Time frame: Baseline and 30, 60, 90, 120, and 180 minutes after meal consumption
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 9 Sep 2026.
- Individual participant dataSharing planned: No
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.
Holt contact
Roberta H Holt, PhD principal investigator
University of California, Davis
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Protease enzyme supplement in people with Postprandial Amino Acid Concentrations in Healthy Adults, run by Amplifye at 1 site in United States.
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 10 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 9 Sep 2026. 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 United States. 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 Roberta Holt, PhD (530-400-5952, rrholt@ucdavis.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Postprandial total amino acid incremental area under the curve after the test meal with P24 versus placebo (time frame: 0 to 180 minutes after meal consumption). 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 9 Sep 2026; AzTrials last refreshed its copy on 7 Nov 2026.