Ulcerative Colitis (UC)Phase 2NCT07747155
A Study to Evaluate the Efficacy, Safety, Tolerability and Pharmacokinetics of PTT-621 in Patients With Moderately to Severely Active Ulcerative Colitis
A Phase 2 study testing PTT-621 Tablets in people with Ulcerative Colitis (UC), run by Pyrotech Therapeutics, Inc. at 1 site in China.
Trial summary
This Phase IIa, multicenter, single-arm trial evaluates the efficacy, safety, tolerability, and pharmacokinetics of PTT-621 tablets in adults (18-70 years) with moderate-to-severe active ulcerative colitis (UC) who have inadequate response/intolerance to standard therapies. Participants receive PTT-621 for 12 weeks. Read more about this study
- Who is it for?
- Ages 18 to 70 years
- Conditions the study is for
- Ulcerative Colitis (UC)
- What is being tested?
- PTT-621 Tablets
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 40 participants
- Where
- 1 siteChina
- Study dates
- Aug 2026to Jun 2028
- 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 to 70 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 1. Male or female participants aged 18-70 years inclusive at screening. 2. Diagnosed with ulcerative colitis (UC) at least 60 days prior to the first dose of IP.
- 3. Participants have active UC at screening, defined as a modified Mayo score of 5-9.
- 4. Endoscopic evidence of UC extending ≥15 cm from the anal verge during the screening period.
- 5. Participants have had inadequate/loss of response or intolerance to at least one of the following: 5-aminosalicylic acid, glucocorticoids, immunosuppressants, biologics, and/or small-molecule targeted therapies.
- 6. Participants currently receiving the following UC therapies are eligible if they meet stability requirements: Oral glucocorticoids: with stable dosing for ≥2 weeks prior to screening endoscopy；Oral 5-ASA: Stable dose for at least 2 weeks prior to the endoscopic assessment during the screening period.
- 7. Female participants of childbearing potential must have a negative serum/urine pregnancy test at screening.
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- 8. Willing to use at least one highly effective contraceptive method during sexual intercourse throughout the study and until 1 month after the last dose of IP.
- 9. Willing to refrain from sperm/ova donation throughout the study and until 1 month after the last dose of IP.
- 10. Able and willing to provide written informed consent and comply with all protocol-specified procedures and visit schedules.
Who cannot join
- 1. A current diagnosis of Crohn's disease (CD), indeterminate colitis, infectious colitis, or any other colitis/enteritis that could interfere with efficacy evaluation； 2. Has UC complications (e.g., fulminant colitis, toxic megacolon, prior total or partial colectomy, or other conditions requiring surgery)； 3. Prior or current gastrointestinal dysplasia； 4. History of gastrointestinal malignancy, or any current evidence of gastrointestinal cancer.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
China1 site
Renji Hospital-Shanghai Jiao Tong University School of Medicine
Shanghai, Shanghai Municipality, 200127
Qi Lu, +86 21 68383575, rjirbzc@vip.163.com
About this study
Official title: A Phase IIa, Multicenter, Single-Arm Study to Evaluate the Efficacy, Safety, Tolerability and Pharmacokinetic Characteristics of PTT-621 in Patients With Moderately to Severely Active Ulcerative
This Phase IIa, multicenter, single-arm trial evaluates the efficacy, safety, tolerability, and pharmacokinetics of PTT-621 tablets in adults (18-70 years) with moderate-to-severe active ulcerative colitis (UC) who have inadequate response/intolerance to standard therapies. Participants receive PTT-621 for 12 weeks. The primary endpoint is the proportion of participants achieving endoscopic improvement at Week 12. Secondary endpoints include safety, clinical remission, clinical response, symptom response, pharmacokinetics, and inflammatory biomarkers. The study is sponsored by Pyrotech Therapeutics, with ethical approval from Renji Hospital's IRB.
- Conditions
- Ulcerative Colitis (UC)
- Being tested
- PTT-621 Tablets
- Keywords
- Ulcerative Colitis, IBD
- Medical subject headings
- Colitis, Ulcerative
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
PTT-621 TabletsDrug
PTT-621 will be administered orally
| Study group | Role | What they receive |
|---|---|---|
| Participants receiving PTT-621 Dose A | Experimental | Not described Receives: Drug: PTT-621 Tablets |
What is being measured
The primary outcome is the main question the study is designed to answer.
Percentage of participants achieving endoscopic improvement at Week 12
Measured: Week 12
Secondary outcomes (6)
Percentage of participants with adverse events (AEs)
Measured: Baseline, Week 2, 4, 8, 12
Percentage of participants achieving clinical remission、clinical response
Measured: Week 12
Percentage of participants achieving symptom remission, symptom response
Measured: Weeks 2, 4, 8, 12
Pharmacokinetic (PK) characteristics: Plasma concentrations of PTT-621
Measured: Baseline, Weeks 2, 4, 8, 12
Changes in fecal calprotectin from baseline
Measured: Weeks 2, 4, 8, 12
Changes in high-sensitivity C-reactive protein (hsCRP) from baseline
Measured: Week 2, 4, 8, 12
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted5 Aug 2026
- Study startAug 2026 (estimated)
- Primary completionDec 2027 (estimated)
- Study completionJun 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Ulcerative Colitis (UC)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
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 40 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Pyrotech Therapeutics, Inc.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07747155
- Sponsor's protocol ID
- PTT-621-201
- Status last verified
- Jul 2026
- First submitted
- 27 Jul 2026
- Last updated
- 7 Aug 2026
- Results posted
- 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 7 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase IIa, Multicenter, Single-Arm Study to Evaluate the Efficacy, Safety, Tolerability and Pharmacokinetic Characteristics of PTT-621 in Patients With Moderately to Severely Active Ulcerative
- ClinicalTrials.gov ID
- NCT07747155
- Acronym / sponsor ID
- PTT-621-201
- Conditions
- Ulcerative Colitis (UC)
- Keywords
- Ulcerative Colitis, IBD
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 40 participants (estimated)
- Lead sponsor
- Pyrotech Therapeutics, Inc.Industry (pharma, biotech, devices)
- Study start
- Aug 2026 (estimated)
- Primary completion
- Dec 2027 (estimated)
- Study completion
- Jun 2028 (estimated)
- First posted
- 5 Aug 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.
This Phase IIa, multicenter, single-arm trial evaluates the efficacy, safety, tolerability, and pharmacokinetics of PTT-621 tablets in adults (18-70 years) with moderate-to-severe active ulcerative colitis (UC) who have inadequate response/intolerance to standard therapies. Participants receive PTT-621 for 12 weeks. The primary endpoint is the proportion of participants achieving endoscopic improvement at Week 12. Secondary endpoints include safety, clinical remission, clinical response, symptom response, pharmacokinetics, and inflammatory biomarkers. The study is sponsored by Pyrotech Therapeutics, with ethical approval from Renji Hospital's IRB.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Participants receiving PTT-621 Dose A | Experimental | Drug: PTT-621 Tablets |
Who may qualify
- Ages
- 18 to 70 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (9 listed)
- 1. Male or female participants aged 18-70 years inclusive at screening. 2. Diagnosed with ulcerative colitis (UC) at least 60 days prior to the first dose of IP.
- 3. Participants have active UC at screening, defined as a modified Mayo score of 5-9.
- 4. Endoscopic evidence of UC extending ≥15 cm from the anal verge during the screening period.
- 5. Participants have had inadequate/loss of response or intolerance to at least one of the following: 5-aminosalicylic acid, glucocorticoids, immunosuppressants, biologics, and/or small-molecule targeted therapies.
- 6. Participants currently receiving the following UC therapies are eligible if they meet stability requirements: Oral glucocorticoids: with stable dosing for ≥2 weeks prior to screening endoscopy；Oral 5-ASA: Stable dose for at least 2 weeks prior to the endoscopic assessment during the screening period.
Key exclusion criteria (1 listed)
- 1. A current diagnosis of Crohn's disease (CD), indeterminate colitis, infectious colitis, or any other colitis/enteritis that could interfere with efficacy evaluation； 2. Has UC complications (e.g., fulminant colitis, toxic megacolon, prior total or partial colectomy, or other conditions requiring surgery)； 3. Prior or current gastrointestinal dysplasia； 4. History of gastrointestinal malignancy, or any current evidence of gastrointestinal cancer.
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 |
|---|---|---|
| PTT-621 TabletsPTT-621 will be administered orally | Drug | Participants receiving PTT-621 Dose A |
Primary outcome
Percentage of participants achieving endoscopic improvement at Week 12
Time frame: Week 12
6 secondary outcomes
Percentage of participants with adverse events (AEs)
Time frame: Baseline, Week 2, 4, 8, 12
Percentage of participants achieving clinical remission、clinical response
Time frame: Week 12
Percentage of participants achieving symptom remission, symptom response
Time frame: Weeks 2, 4, 8, 12
Pharmacokinetic (PK) characteristics: Plasma concentrations of PTT-621
Time frame: Baseline, Weeks 2, 4, 8, 12
Changes in fecal calprotectin from baseline
Time frame: Weeks 2, 4, 8, 12
Changes in high-sensitivity C-reactive protein (hsCRP) from baseline
Time frame: Week 2, 4, 8, 12
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 7 Aug 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.
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 PTT-621 Tablets in people with Ulcerative Colitis (UC), run by Pyrotech Therapeutics, Inc. at 1 site in China.
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 9 inclusion and 1 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 7 Aug 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 China. 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 Ran Wei (+86 10 81938094, ran.wei@pyrotech.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Percentage of participants achieving endoscopic improvement at Week 12 (time frame: Week 12). 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 7 Aug 2026.