General information
  • Disease category Digestive Systems diseases (non cancer) (BASEC)
  • Study Phase Phase 2 (ICTRP)
  • Recruitment status recruitment ongoing (BASEC/ICTRP)
  • Trial sites
    Bern
    (BASEC)
  • Contact Prof Dr. med. Frank Seibold studien.seibold@intesto.ch (BASEC)
  • Data Source(s) BASEC: Import from 07.01.2026 ICTRP: Import from 15.03.2026
  • Last update 15.03.2026 02:00
HumRes63610 | SNCTP000005427 | BASEC2022-01995 | NCT06029972

Study to assess the efficacy and safety of GS-5290 in adults with moderate to severe active ulcerative colitis (Palekona)

  • Disease category Digestive Systems diseases (non cancer) (BASEC)
  • Study Phase Phase 2 (ICTRP)
  • Recruitment status recruitment ongoing (BASEC/ICTRP)
  • Trial sites
    Bern
    (BASEC)
  • Contact Prof Dr. med. Frank Seibold studien.seibold@intesto.ch (BASEC)
  • Data Source(s) BASEC: Import from 07.01.2026 ICTRP: Import from 15.03.2026
  • Last update 15.03.2026 02:00

Summary description of the study

The purpose of this study is to find out whether GS-5290 is effective and safe in treating individuals with moderate to severe ulcerative colitis (UC). In the study, participants will be compared in different treatment groups with GS-5290 to individuals receiving a placebo. The individuals receiving placebo will get tablets that look like GS-5290 but contain no active ingredient. About 176 participants will be included in this study, 5 of whom will be in Switzerland. The study will be conducted at approximately 125 trial centers in around 15 countries. One trial center is located in Switzerland. The study participation will last a maximum of 52 weeks for participants who respond and 64 weeks for participants who do not respond (not including pre-examinations and follow-up). Participants may not derive any benefit from participating in this study. Participants help future patients with their participation. GS-5290 has been administered to healthy volunteers in two ongoing Phase I studies. In the first-in-human study, 42 volunteers received GS-5290 over a short period (1 day or 10 days) to determine whether it causes any undesirable or harmful side effects. Only a few side effects were reported, and all were of mild nature. Almost half of the volunteers who received GS-5290 showed increases in two substances in the blood (creatinine and bilirubin). The increases were mild to moderate without associated symptoms. The creatinine and bilirubin levels decreased after discontinuation of GS-5290.

(BASEC)

Intervention under investigation

Patients who agree to participate in this study and meet all inclusion criteria will be assigned to a treatment and have a 25% chance of receiving GS-5290 (600 mg), a 25% chance of receiving GS-5290 (300 mg), a 25% chance of receiving GS-5290 (150 mg), and a 25% chance of receiving placebo during the first 12 weeks of the study.

Patients who respond to treatment at week 12 according to the investigator can continue the blinded treatment (neither the participant nor the doctor knows whether placebo or active substance is being taken) and will receive either 300 mg or 150 mg of GS-5290 depending on their prior assignment. If no clinical response is observed at week 12 during the blinded treatment period, patients may receive 300 mg or 600 mg of GS-5290 daily for 12 weeks depending on their prior assignment, if they agree. At week 12 of the treatment phase for non-responding participants, participants who achieve a clinical response are eligible to receive 300 mg of GS-5290 once daily until week 52, if they agree.

(BASEC)

Disease under investigation

Moderate to severe active ulcerative colitis (UC)

(BASEC)

Criteria for participation in trial
1) Men or non-pregnant women aged 18 to 75 years 2) Ulcerative colitis (UC) of at least 90 days duration prior to randomization, confirmed by endoscopy and histology at any time in the past AND a minimum disease extent of 15 cm from the anal margin. 3) Moderately to severely active UC. 4) Previous treatment with an approved UC therapy with at least one predefined mechanism of action for novel therapies, but failure. 5) Ability to understand and sign a written informed consent. (BASEC)

Exclusion criteria
1) Current diagnosis of Crohn's disease (a chronic inflammation in the gastrointestinal tract) or diagnosis of indeterminate colitis. 2) Participants with a disease limited to the rectum. 3) Female participants who were assigned female at birth, are pregnant, breastfeeding, wish to become pregnant, or are of childbearing age and are not using an appropriate method of contraception. 4) Known hypersensitivity to the study drug, its metabolites, or a formulation excipient. 5) Participants who are susceptible to hyperbilirubinemia, as determined by UGT1A1 genotyping. 6) Requirement for ongoing therapy with or previous use of prohibited medications listed in the protocol. 7) Previous surgery for ulcerative colitis. Additional inclusion/exclusion criteria defined in the protocol apply. (BASEC)

Trial sites

Bern

(BASEC)

Australia, Austria, Belgium, Canada, France, Germany, Hungary, Italy, Japan, Poland, South Korea, Switzerland, United Kingdom, United States (ICTRP)

Sponsor

Gielead Sceinces Switzerland Sàrl

(BASEC)

Contact

Contact Person Switzerland

Prof Dr. med. Frank Seibold

+41 31 302 32 34

studien.seibold@intesto.ch

Intesto

(BASEC)

General Information

Gilead Sciences,

1-833-445-3230 (GILEAD-0)

GileadClinicalTrials@gilead.com

(ICTRP)

General Information

Gilead Sciences

1-833-445-3230 (GILEAD-0)

GileadClinicalTrials@gilead.com

(ICTRP)

Scientific Information

Gilead Sciences,

1-833-445-3230 (GILEAD-0)

GileadClinicalTrials@gilead.com

(ICTRP)

Name of the authorising ethics committee (for multicentre studies, only the lead committee)

Ethics Committee Bern

(BASEC)

Date of authorisation

30.03.2023

(BASEC)


ICTRP Trial ID
NCT06029972 (ICTRP)

Official title (approved by ethics committee)
A Phase 2, Double-Blinded, Randomized, Placebo-Controlled, Dose-Ranging Study Evaluating the Efficacy and Safety of GS-5290 in Participants With Moderately to Severely Active Ulcerative Colitis (BASEC)

Academic title
A Phase 2, Double-Blinded, Randomized, Placebo-Controlled, Dose-Ranging Study Evaluating the Efficacy and Safety of GS-5290 in Participants With Moderately to Severely Active Ulcerative Colitis (ICTRP)

Public title
Study of Tilpisertib Fosmecarbil in Participants With Moderately to Severely Active Ulcerative Colitis (ICTRP)

Disease under investigation
Ulcerative Colitis (ICTRP)

Intervention under investigation
Drug: Tilpisertib FosmecarbilDrug: Placebo (ICTRP)

Type of trial
Interventional (ICTRP)

Trial design
Allocation: Randomized. Intervention model: Parallel Assignment. Primary purpose: Treatment. Masking: Double (Participant, Investigator). (ICTRP)

Inclusion/Exclusion criteria
Key Inclusion Criteria:

- Individuals assigned male at birth, or nonpregnant, nonlactating individuals
assigned female at birth, 18 to 75 years of age based on the date of the screening
visit.

- Ulcerative colitis (UC) of at least 90-day duration before randomization confirmed
by endoscopy and histology at any time in the past AND a minimum disease extent of
15 cm from the anal verge. Documentation of endoscopy and histology consistent with
the diagnosis of UC must be available in the source documents prior to the
initiation of screening.

- Moderately to severely active UC as determined during screening with a modified Mayo
Clinic Score based on the sum of Stool Frequency, Rectal Bleeding, and Endoscopic
Finding of 5 to 9 points and an endoscopic subscore of 2 to 3 (determined by central
reader).

- Previous treatment history of approved UC therapy with at least one advanced therapy
mechanisms of action but failure (ie, loss of response or lack of response) of no
more than 3 different advanced therapy mechanisms of action.

- A surveillance colonoscopy for dysplasia is required prior to randomization if
indicated by regional guidelines for individuals with UC.

Key Exclusion Criteria:

- Current diagnosis of Crohn's Disease (CD) or diagnosis of indeterminate colitis due
to an enteric pathogen, lymphocytic or collagenous colitis.

- Individuals with disease limited to the rectum (ulcerative proctitis) during
screening endoscopy.

- Requirement for ongoing therapy with or prior use of any prohibited medications.

- Active clinically significant infection, or any infection requiring hospitalization
or treatment with intravenous anti-infectives within 8 weeks.

of randomization or any infection requiring oral anti-infective therapy within 6 weeks
of randomization.

- History of opportunistic infection.

- Current diagnosis of acute severe colitis, fulminant colitis, or toxic megacolon.

Note: Other protocol-defined Inclusion/Exclusion criteria may apply. (ICTRP)

not available

Primary and secondary end points
Proportion of Participants Achieving Clinical Response Per Modified Mayo Clinic Score at Week 12 (ICTRP)

Proportion of Participants Achieving Clinical Remission Per Modified Mayo Clinic Score at Week 12;Proportion of Participants Achieving Endoscopic Response at Week 12;Proportion of Participants Achieving Histologic Endoscopic Mucosal Improvement at Week 12;Percentage of Participants Experiencing Treatment-emergent Adverse Events (TEAEs);Percentage of Participants Experiencing Clinically Significant Laboratory Abnormalities (ICTRP)

Registration date
not available

Incorporation of the first participant
not available

Secondary sponsors
not available

Additional contacts
Gilead Study Director;Gilead Clinical Study Information Center, GileadClinicalTrials@gilead.com, 1-833-445-3230 (GILEAD-0), Gilead Sciences, (ICTRP)

Secondary trial IDs
2022-501119-14, jRCT2031230403, GS-US-457-6411 (ICTRP)

Results-Individual Participant Data (IPD)
not available

Further information on the trial
https://clinicaltrials.gov/study/NCT06029972 (ICTRP)

Results of the trial

Results summary

not available

Link to the results in the primary register

not available