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NCT03595683

Pembrolizumab and EDP1503 in Advanced Melanoma

Terminated Phase 2 Results posted Last updated 8 December 2025
What this trial tests

Phase 2 trial testing Pembrolizumab in Melanoma (Skin) in 8 participants. Terminated before completion.

Timeline
2 October 2018
Primary endpoint
31 July 2025
31 July 2025

Quick facts

Lead sponsorUniversity of Chicago
PhasePhase 2
StatusTerminated
Study typeINTERVENTIONAL
Allocationnon randomized
Designparallel
Maskingnone
Primary purposetreatment
Enrollment8
Start date2 October 2018
Primary completion31 July 2025
Estimated completion31 July 2025
Sites1 location across United States

Drugs / interventions tested

Conditions studied

Sponsor

University of Chicago

Who can join

18 and older, any sex, with Melanoma (Skin) or Melanoma. Patients with the condition only — healthy volunteers not accepted.

Results — posted to ClinicalTrials.gov

Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.

Response Rate Primary · 2 years

For Cohort 1, based on deep response (\>80% tumor reduction). Assessed by standard RECIST criteria for Cohort 2 (complete + partial response).

GroupValue95% CI
Cohort 1: Anti-PD1 Naive0
Cohort 2: Anti-PD1 Refractory0
Number of Participants With EPD1503 Related Adverse Events During the Run in Period Primary · 2 weeks

Assessed by CTCAE v4.0, grade 3 or higher

GroupValue95% CI
Cohort 1: Anti-PD1 Naive0
Cohort 2: Anti-PD1 Refractory0
Progression Free Survival (PFS) Secondary · 2 years

Time from first dose of either drug until disease progression or death from any cause. Surviving subjects without progression will be censored as of the date of the last negative examination. Estimated using the Kaplan-Meier method

GroupValue95% CI
Cohort 1: Anti-PD1 Naive8.6± 0.5
Cohort 2: Anti-PD1 Refractory2.7± 0.7
Number of Participants With Treatment Related Adverse Events During Combination Therapy Secondary · 2 years

Assessed by CTCAE v4.0, grade 3 or higher

GroupValue95% CI
Cohort 1: Anti-PD1 Naive1
Cohort 2: Anti-PD1 Refractory0

Adverse events — posted to ClinicalTrials.gov

Time frame: 2 years. Reporting threshold: 0%. Adverse-event reports describe events observed during the trial — not all are caused by the drug.

Cohort 1: Anti-PD1 Naive
Serious: 1/3 (33%)
Deaths: 1/3
Cohort 2: Anti-PD1 Refractory
Serious: 1/5 (20%)
Deaths: 3/5

Serious adverse events (5 terms)

ReactionSystemCohort 1: Anti-PD1 NaiveCohort 2: Anti-PD1 Refract…
SepsisInfections and infestations
PancreatitisGastrointestinal disorders
Lipase increasedInvestigations
FatigueGeneral disorders
DehydrationMetabolism and nutrition disorders
Other adverse events (14 terms — click to expand)

ReactionSystemCohort 1: Anti-PD1 NaiveCohort 2: Anti-PD1 Refract…
FatigueGeneral disorders
RashSkin and subcutaneous tissue disorders
PruritusSkin and subcutaneous tissue disorders
Abdominal painGastrointestinal disorders
ArthralgiaMusculoskeletal and connective tissue disorders
Hot flashesVascular disorders
Peripheral sensory neuropathyNervous system disorders
Alanine aminotransferase increasedInvestigations
HypocalcemiaMetabolism and nutrition disorders
HypokalemiaMetabolism and nutrition disorders
Platelet count decreasedInvestigations
Serum amylase increasedInvestigations
Elevated TSHInvestigations
BruisingInjury, poisoning and procedural complications

Most-reported serious reactions: Sepsis, Pancreatitis, Lipase increased, Fatigue, Dehydration.

Data from ClinicalTrials.gov NCT03595683 adverse events section.

Sponsor's own description

This study is being done to determine if orally administered EDP1503 will enhance the response to standard immunotherapy treatment (pembrolizumab) in participants with advanced melanoma. The study will involve initial administration of EDP1503 for a run-in period (2 weeks) followed by administration of both EDP1503 (twice daily) and pembrolizumab (every 3 weeks). Mandatory biopsies are required before starting study treatment and after 2 weeks of EDP1503 dosing.

Publications & conference data

8 peer-reviewed publications reference this trial (live from Europe PMC):

  1. Cancer and the Microbiome-Influence of the Commensal Microbiota on Cancer, Immune Responses, and Immunotherapy.
    Matson V, Chervin CS, Gajewski TF. · · 2021 · cited 286× · PMID 33253684 · DOI 10.1053/j.gastro.2020.11.041
  2. Cold and hot tumors: from molecular mechanisms to targeted therapy.
    Wu B, Zhang B, Li B, Wu H, et al · · 2024 · cited 280× · PMID 39420203 · DOI 10.1038/s41392-024-01979-x
  3. The role of the tumor microbe microenvironment in the tumor immune microenvironment: bystander, activator, or inhibitor?
    Ma J, Huang L, Hu D, Zeng S, et al · · 2021 · cited 105× · PMID 34656142 · DOI 10.1186/s13046-021-02128-w
  4. The gut microbiome: what the oncologist ought to know.
    Lee KA, Luong MK, Shaw H, Nathan P, et al · · 2021 · cited 90× · PMID 34262150 · DOI 10.1038/s41416-021-01467-x
  5. Role of gut microbiome in cancer immunotherapy: from predictive biomarker to therapeutic target.
    Zhang M, Liu J, Xia Q. · · 2023 · cited 77× · PMID 37770953 · DOI 10.1186/s40164-023-00442-x
  6. Modulating gut microbiome in cancer immunotherapy: Harnessing microbes to enhance treatment efficacy.
    Kang X, Lau HC, Yu J. · · 2024 · cited 65× · PMID 38631285 · DOI 10.1016/j.xcrm.2024.101478
  7. Intestinal microbiota: a new force in cancer immunotherapy.
    Dai Z, Zhang J, Wu Q, Fang H, et al · · 2020 · cited 62× · PMID 32522267 · DOI 10.1186/s12964-020-00599-6
  8. Manipulating Gut Microbiota Composition to Enhance the Therapeutic Effect of Cancer Immunotherapy.
    Yi M, Jiao D, Qin S, Chu Q, et al · · 2019 · cited 46× · PMID 31517538 · DOI 10.1177/1534735419876351

Verify or expand the search:

Other trials of Pembrolizumab

Trials testing the same drug.

Other recruiting trials for Melanoma (Skin)

Currently open trials in the same condition.

Other University of Chicago trials

Trials by the same sponsor.

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