Type 1 Diabetes (T1D)Phase 2Hybrid CATT1NCT07616206
Cadisegliatin as Adjunctive Therapy to Insulin in Participants With Type 1 Diabetes Who Are Using Hybrid Closed Loop (HCL) Systems
A Phase 2 study testing Cadisegliatin 800 mg QD in people with Type 1 Diabetes (T1D), run by vTv Therapeutics at 1 site in United States.
Trial summary
TTP399-206 is a Phase 2a multicenter double blind cross over randomized study of cadisegliatin in participants with T1D using hybrid closed loop systems to manage their diabetes. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Type 1 Diabetes (T1D)
- What is being tested?
- Cadisegliatin 800 mg QD
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 40 participants
- Where
- 1 siteUnited States
- Study dates
- Oct 2026to Jun 2027
- Phase
- Phase 2
- 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
- Participants >= 18 years of age
- Fasting C-peptide levels <0.6 ng/ml
- Average TIR < 70% recorded on their personal CGM data collected over the past 7 days prior to Visit 1
- Currently on a hybrid closed loop device for at least 3 months and willing to stay on the same model of pump device for study duration
- Willing to wear a study provided CGM for study duration
- Total bilirubin ≤2×ULN, ALT and AST ≤3×ULN
Who cannot join
- Have Type 2 Diabetes Mellitus (DM), monogenic diabetes, maturity-onset diabetes, other unusual or rare forms of DM, or diabetes resulting from a secondary disease.
- Have been hospitalized for DKA within 3 months
- Have uncontrolled hypothyroidism or hyperthyroidism
- Have QTcF interval > 450 msec for males or > 470 msec for females
- Have a personal or family history of long QT syndrome, Torsades de pointes, or other complex ventricular arrhythmias
- Have persistent, uncontrolled hypertension
Show all 11Show fewer
- Have clinically significant cardiovascular or cerebrovascular disease
- Have proliferative retinopathy or maculopathy requiring acute treatment
- Have a serious concomitant systemic disorder including but not limited to HIV or active Hep B or Hep C
- Have been diagnosed and/or treated for malignancy within 3 years
- Have used any of the following medications within the specified time periods: any non-insulin anti-diabetic therapies (e.g.SGLT-2 inhibitors, GLP-1 receptor agonists, metformin, sulfonylureas, DPP-4 inhibitors, pramlintide, a-glucosidase inhibitors, or glucose dependent insulinotropic polypeptide agonists) within 30 days, antipsychotic medications (e.g. olanzapine, risperidone, clozapine, quetiapine, and haloperidol) within 30 days, systemic corticosteroids for ≥7 days for a temporary medical condition within 30 days,
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site
Atlanta Diabetes Associates
Atlanta, Georgia, 30318
Bruce W Bode, MD
About this study
Official title: Hybrid CATT1: Hybrid Closed Loop Insulin Pumps With Cadisegliatin as Adjunctive Treatment in Patients With Type 1 Diabetes A Phase 2a Double Blind Randomized Cross-Over Study
TTP399-206 is a Phase 2a multicenter double blind cross over randomized study of cadisegliatin in participants with T1D using hybrid closed loop systems to manage their diabetes. Participants using a hybrid closed loop insulin pump to manage their diabetes will be randomized to either receive blinded cadisegliatin 800 mg QD as an adjunctive therapy to their insulin treatment or placebo QD along with their insulin treatment. The trial begins with a screening period of up to 2 weeks, followed by a device training and insulin adjustment period of 1-2 weeks leading into the first double-blind treatment period of 6 weeks. There will then be a washout period of 2 weeks followed by the second double-blind treatment period of 6 weeks where the participants will cross-over to the treatment that they did not receive in the first treatment period.
Read the detailed description
TTP399-206 is a 20 week, Phase 2a trial designed to evaluate efficacy and safety of cadisegliatin in participants with T1D who are using hybrid closed loop (HCL) systems to manage their condition to gather preliminary data to understand how cadisegliatin performs in an HCL setting.
- Conditions
- Type 1 Diabetes (T1D)
- Being tested
- Cadisegliatin 800 mg QD, Placebo
- Keywords
- Hybrid Closed Loop
- 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.
Cadisegliatin 800 mg QDDrug
Also called TTP399
Cadisegliatin is an orally bioavailable small-molecule glucokinase activator, adjunctive therapy to insulin
PlaceboDrug
Placebo (insulin alone)
| Study group | Role | What they receive |
|---|---|---|
| Cadisegliatin 800 mg QD, then Placebo | Experimental | If a participant is randomized to receive cadisegliatin 800 mg QD as an adjunctive therapy to their insulin treatment in the first double-blind treatment period of 6 weeks, there will then be a washout period of 2 weeks followed by the second double-blind treatment period of 6 weeks where the participant will cross-over to the placebo QD along with their insulin treatment Receives: Drug: Cadisegliatin 800 mg QD; Drug: Placebo |
| Placebo, then Cadisegliatin 800 mg QD | Experimental | If a participant is randomized to receive placebo QD along with their insulin treatment in the first double-blind treatment period of 6 weeks, there will then be a washout period of 2 weeks followed by the second double-blind treatment period of 6 weeks where the participant will cross-over to the cadisegliatin 800 mg QD as an adjunctive therapy to their insulin treatment Receives: Drug: Cadisegliatin 800 mg QD; Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
To assess the change in Time in Range (TIR)
Time in Range (TIR) based on study CGM in participants with T1D who are using hybrid closed loop systems on cadisegliatin vs placebo
Measured: last 2 weeks of the two 6-week treatment periods
Secondary outcomes (14)
CGM-based metric for glycemic control
Time In Tight Range (TITR)
Measured: last 2 weeks of each treatment period
CGM-based metric for glycemic control
Time Above Range (TAR)
Measured: last 2 weeks of each treatment period
CGM-based metric for glycemic control
Time Below Range (TBR)
Measured: last 2 weeks of each treatment period
CGM-based metric for glycemic control
Glucose Management Indicator (GMI)
Measured: last 2 weeks of each treatment period
CGM-based metric for glycemic control
Glucose variability (GV)
Measured: last 2 weeks of each treatment period
CGM-based metric for glycemic control
Time in Range (TIR) > 70%
Measured: last 2 weeks of each treatment period
Change in glucose control after standardized mixed meal tolerance test (MMTT)
Glucose Peak Plasma Concentration (Cmax) based on study CGM after standardized mixed meal tolerance test (MMTT)
Measured: 12 weeks
Change in glucose control after standardized mixed meal tolerance test (MMTT)
Glucose Area under the plasma concentration versus time curve (AUC) based on study CGM after standardized mixed meal tolerance test (MMTT)
Measured: 12 weeks
To assess the change in Level 1, Level 2 , and Level 3 hypoglycemic incidence
Number of events of Level 1 and Level 2 hypoglycemia as determined by CGM and Level 3 hypoglycemic events in participants with T1D who are using hybrid closed loop systems on cadisegliatin vs placebo
Measured: 12 weeks
Assess incidence of Serious Adverse Events (SAEs)
Number of Serious Adverse Events (SAEs)
Measured: 14 weeks
Assess incidence of Treatment Emergent Adverse Events (TEAEs)
Number of treatment emergent adverse events (TEAEs)
Measured: 14 weeks
Assess incidence of Treatment Emergent Adverse Events (TEAEs) leading to discontinuation
Number of treatment emergent adverse events (TEAEs) leading to discontinuation of study drug
Measured: 14 weeks
Assess incidence of Adverse Events of Special Interest (AESIs)
Number of adverse events of special interest (AESIs)
Measured: 14 weeks
Change from baseline in average daily total insulin dose
Change from baseline in average daily total insulin dose in units (IU) based on manual entry in eDiary records from participants with T1D who are using hybrid closed loop systems on cadisegliatin vs placebo
Measured: last week of the two 6-week treatment periods
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted1 Jun 2026
- Study startOct 2026 (estimated)
- Primary completionJun 2027 (estimated)
- Study completionJun 2027 (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 (T1D)Studies 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 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Model description
- Double-blind placebo-controlled, cross-over
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 40 participants (estimated)
Sponsor and investigators
- Lead sponsor
- vTv Therapeutics
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Maria Alba, MD, Study director, vTv Therapeutics LLC
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07616206
- Sponsor's protocol ID
- TTP399-206
- Acronym
- Hybrid CATT1
- Status last verified
- Sep 2026
- First submitted
- 15 May 2026
- Last updated
- 21 Sep 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 21 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Hybrid CATT1: Hybrid Closed Loop Insulin Pumps With Cadisegliatin as Adjunctive Treatment in Patients With Type 1 Diabetes A Phase 2a Double Blind Randomized Cross-Over Study
- ClinicalTrials.gov ID
- NCT07616206
- Acronym / sponsor ID
- Hybrid CATT1 / TTP399-206
- Conditions
- Type 1 Diabetes (T1D)
- Keywords
- Hybrid Closed Loop
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 40 participants (estimated)
- Lead sponsor
- vTv TherapeuticsIndustry (pharma, biotech, devices)
- Study start
- Oct 2026 (estimated)
- Primary completion
- Jun 2027 (estimated)
- Study completion
- Jun 2027 (estimated)
- First posted
- 1 Jun 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.
TTP399-206 is a Phase 2a multicenter double blind cross over randomized study of cadisegliatin in participants with T1D using hybrid closed loop systems to manage their diabetes. Participants using a hybrid closed loop insulin pump to manage their diabetes will be randomized to either receive blinded cadisegliatin 800 mg QD as an adjunctive therapy to their insulin treatment or placebo QD along with their insulin treatment. The trial begins with a screening period of up to 2 weeks, followed by a device training and insulin adjustment period of 1-2 weeks leading into the first double-blind treatment period of 6 weeks. There will then be a washout period of 2 weeks followed by the second double-blind treatment period of 6 weeks where the participants will cross-over to the treatment that they did not receive in the first treatment period.
Detailed description
TTP399-206 is a 20 week, Phase 2a trial designed to evaluate efficacy and safety of cadisegliatin in participants with T1D who are using hybrid closed loop (HCL) systems to manage their condition to gather preliminary data to understand how cadisegliatin performs in an HCL setting.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Double blind (participant, investigator)
- Number of arms
- 2
- Model description
- Double-blind placebo-controlled, cross-over
| Arm | Type | Receives |
|---|---|---|
| Cadisegliatin 800 mg QD, then Placebo | Experimental | Drug: Cadisegliatin 800 mg QD, Drug: PlaceboIf a participant is randomized to receive cadisegliatin 800 mg QD as an adjunctive therapy to their insulin treatment in the first double-blind treatment period of 6 weeks, there will then be a washout period of 2 weeks followed by the second double-blind treatment period of 6 weeks where the participant will cross-over to the placebo QD along with their insulin treatment |
| Placebo, then Cadisegliatin 800 mg QD | Experimental | Drug: Cadisegliatin 800 mg QD, Drug: PlaceboIf a participant is randomized to receive placebo QD along with their insulin treatment in the first double-blind treatment period of 6 weeks, there will then be a washout period of 2 weeks followed by the second double-blind treatment period of 6 weeks where the participant will cross-over to the cadisegliatin 800 mg QD as an adjunctive therapy to their insulin treatment |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Participants >= 18 years of age
- Fasting C-peptide levels <0.6 ng/ml
- Average TIR < 70% recorded on their personal CGM data collected over the past 7 days prior to Visit 1
- Currently on a hybrid closed loop device for at least 3 months and willing to stay on the same model of pump device for study duration
- Willing to wear a study provided CGM for study duration
Key exclusion criteria (11 listed)
- Have Type 2 Diabetes Mellitus (DM), monogenic diabetes, maturity-onset diabetes, other unusual or rare forms of DM, or diabetes resulting from a secondary disease.
- Have been hospitalized for DKA within 3 months
- Have uncontrolled hypothyroidism or hyperthyroidism
- Have QTcF interval > 450 msec for males or > 470 msec for females
- Have a personal or family history of long QT syndrome, Torsades de pointes, or other complex ventricular arrhythmias
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 |
|---|---|---|
| Cadisegliatin 800 mg QDAlso: TTP399Cadisegliatin is an orally bioavailable small-molecule glucokinase activator, adjunctive therapy to insulin | Drug | Cadisegliatin 800 mg QD, then Placebo, Placebo, then Cadisegliatin 800 mg QD |
| PlaceboPlacebo (insulin alone) | Drug | Cadisegliatin 800 mg QD, then Placebo, Placebo, then Cadisegliatin 800 mg QD |
Primary outcome
To assess the change in Time in Range (TIR)
Time frame: last 2 weeks of the two 6-week treatment periods
Time in Range (TIR) based on study CGM in participants with T1D who are using hybrid closed loop systems on cadisegliatin vs placebo
14 secondary outcomes
CGM-based metric for glycemic control
Time frame: last 2 weeks of each treatment period
CGM-based metric for glycemic control
Time frame: last 2 weeks of each treatment period
CGM-based metric for glycemic control
Time frame: last 2 weeks of each treatment period
CGM-based metric for glycemic control
Time frame: last 2 weeks of each treatment period
CGM-based metric for glycemic control
Time frame: last 2 weeks of each treatment period
CGM-based metric for glycemic control
Time frame: last 2 weeks of each treatment period
Change in glucose control after standardized mixed meal tolerance test (MMTT)
Time frame: 12 weeks
Change in glucose control after standardized mixed meal tolerance test (MMTT)
Time frame: 12 weeks
To assess the change in Level 1, Level 2 , and Level 3 hypoglycemic incidence
Time frame: 12 weeks
Assess incidence of Serious Adverse Events (SAEs)
Time frame: 14 weeks
Assess incidence of Treatment Emergent Adverse Events (TEAEs)
Time frame: 14 weeks
Assess incidence of Treatment Emergent Adverse Events (TEAEs) leading to discontinuation
Time frame: 14 weeks
Assess incidence of Adverse Events of Special Interest (AESIs)
Time frame: 14 weeks
Change from baseline in average daily total insulin dose
Time frame: last week of the two 6-week treatment periods
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 21 Sep 2026.
- Individual participant dataSharing planned: Undecided
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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.
Maria Alba, MD study director
vTv Therapeutics LLC
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Cadisegliatin 800 mg QD in people with Type 1 Diabetes (T1D), run by vTv Therapeutics 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 6 inclusion and 11 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: opening soon, as of the sponsor's last update on 21 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. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
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 Meaghan Marnell ((336) 888-0435, clinicaltrials@vtvtherapeutics.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
To assess the change in Time in Range (TIR) (time frame: last 2 weeks of the two 6-week treatment periods). 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 21 Sep 2026.