Phase 1b Clinical Study in Patients With Active Ulcerative Colitis (TP317-301)

A Randomized, Double-Blind, Placebo-Controlled, Multi-Center Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Efficacy Signal of TP-317 in Patients With Active Ulcerative Colitis

Purpose of study is to evaluate the safety, tolerability, pharmacokinetics of TP317 vs. placebo in adults with active ulcerative colitis. Participants will be randomly assigned to receive either daily oral tablets (8 tablets) of TP317 (80 mg) or an identical placebo pill. Study will include 2 colonoscopies, daily dosing (including at home and in clinic), safety assessments, diary and questionnaire completion and 5 in clinic visits.

Study Overview

• Status: Not yet recruiting
• Conditions: Ulcerative Colitis (UC)
• Intervention / Treatment: Drug: TP317; Drug: Matching placebo

• Study Type: Interventional
• Enrollment (Estimated): 24
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: Head of Clinical Development Operations; Phone Number: 203-936-8936; Email: bpaperiello@thetispharma.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Diagnosis of UC with disease duration of at least 12 weeks prior to randomization

• Evidence of active UC at Screening, defined by all of the following:

  1. MMS of 5 to 8, inclusive;
  2. ES ≥ 2;
  3. RBS of ≥ 1; and
  4. Evidence of active UC extending ≥15 cm from the anal verge via colonoscopy (confirmed by central read)

• UCEIS score ≥ 4 with erosion/ulcer sub-score of ≥1 (confirmed by central read)

• An inadequate response to, loss of response to, or intolerance to at least 1 of the following conventional therapies as defined below:

  1. Oral 5-ASA compounds
  2. Glucocorticoids (topical or systemic)
  3. Thiopurines

• If receiving oral 5-aminosalicylates (5-ASAs) or oral corticosteroids (≤20 mg prednisolone equivalent) for treatment of their UC, they must be on a stable dose for at least 28 days prior to randomization

• Previous exposure to a single biologic agent, JAK inhibitor, or S1P inhibitor is allowed (not required) if it was discontinued for reasons other than primary no response. Discontinuation must have been more than 8 weeks or 5 half-lives (whichever is longer) prior to first dose of study treatment.

Exclusion Criteria:

• Severe extensive colitis as evidenced by:

  1. Likeliness to require hospitalization for medical care or surgical intervention of any kind for UC (e.g., colectomy) within 12 weeks after randomization
  2. Current evidence of fulminant colitis, toxic megacolon, or recent history (within 6 months prior to screening) of toxic megacolon, or bowel perforation

• Has severe UC during as defined by ≥6 bloody stools per day AND at least 1 of the following during Screening:

  1. Pulse >90 bpm
  2. Oral temperature of >37.8 °C
  3. Hemoglobin <10.5 g/dL
  4. CRP of >30 mg/L
  5. Erythrocyte sedimentation rate >30 mm/h

• Diagnosis of Crohn's disease (CD) or indeterminate colitis, microscopic colitis, ischemic colitis, radiation colitis, acute diverticulitis, or the presence or history of a fistula consistent with CD based on medical history

• History of or current evidence of colonic dysplasia; or recent history (within 2 years prior to randomization). Note: If adenomatous polyps present, must be completely removed per routine practice prior to the study participant's first dose of investigational product.

• History of colectomy (total or subtotal), ileoanal pouch, Kock pouch, or ileostomy; or is planning to undergo bowel surgery during the course of the study.

• History of spontaneous gastrointestinal (GI) perforation (other than appendicitis or mechanical injury), or at significantly increased risk of GI perforation based on the Investigator's judgment

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Active TP317 80 mg; Participants will receive 8 tablets (80 mg) of TP317 daily, via oral administration for 12 weeks	Drug: TP317; 8 tablets (80 mg) of TP317 oral tablets, taken once daily under fasted conditions for a total duration of 12 weeks.
Placebo Comparator: Placebo; Participants will receive 8 tablets of matching Placebo daily, via oral administration for 12 weeks	Drug: Matching placebo; Matching oral tablet containing no active ingredients, taken once daily for 12 weeks to maintain blinding.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Safety of TP317	Incidence, duration and severity of all adverse events (AEs).	Collected from baseline through Week 12
Safety of TP317	Number of Participants with Clinically Significant Laboratory Abnormalities	Baseline through Week 12
Safety of TP317	Number of Participants with Clinically Significant ECG Abnormalities	Baseline through Week 12
Safety of TP317	Changes in 12-lead electrocardiogram parameters	Baseline to Week 12
Pharmacokinetics of TP317	Maximum observed plasma concentration (Cmax) of TP317	Baseline through Week 12
Pharmacokinetics of TP317	Time to maximum observed plasma concentration (Tmax) of TP317	Baseline through Week 12
Pharmacokinetics of TP317	Area under the plasma concentration-time curve	Baseline through Week 12
Pharmacokinetics of TP317	Plasma elimination half-life (t1/2) of TP317	Baseline through Week 12

Collaborators and Investigators

• Sponsor: Thetis Pharmaceuticals LLC

Study record dates

Study Major Dates

• Study Start (Estimated): September 16, 2026
• Primary Completion (Estimated): July 29, 2027
• Study Completion (Estimated): August 29, 2027

Study Registration Dates

• First Submitted: July 20, 2026
• First Submitted That Met QC Criteria: September 16, 2026
• First Posted (Actual): September 22, 2026

Study Record Updates

• Last Update Posted (Actual): September 22, 2026
• Last Update Submitted That Met QC Criteria: September 16, 2026
• Last Verified: September 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Intestinal Diseases; Digestive System Diseases; Gastrointestinal Diseases; Colonic Diseases; Gastroenteritis; Inflammatory Bowel Diseases; Colitis; Colitis, Ulcerative
• Other Study ID Numbers: TP317-301

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No