Ph II Intraperitoneal Paclitaxel + System Therapy in GI Ca w/Peritoneal Carcinomatosis (STOPGAP-B)

Phase II Basket Trial of Intraperitoneal Paclitaxel Plus Systemic Therapy in Gastrointestinal Malignancies With Peritoneal Carcinomatosis (STOPGAP - B)

This is a phase II open-label, basket clinical trial to assess the feasibility of systemic and Intraperitoneal chemotherapy in subjects with Gastrointestinal Malignancies with Peritoneal Carcinomatosis. These are subjects who have a proven primary carcinoma of the digestive tract..

Study Overview

• Status: Recruiting
• Conditions: Esophageal Carcinoma; Colorectal Adenocarcinoma; Appendiceal Adenocarcinoma; Small Bowel Adenocarcinoma; Gastric Cancer (Diagnosis); Hepatobiliary Carcinoma in Situ
• Intervention / Treatment: Drug: Paclitaxel Q2W; Drug: Paclitaxcel Q3W

• Study Type: Interventional
• Enrollment (Estimated): 55
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Chao Family Comprehensive Cancer Center University of California, Irvine; Phone Number: 1-877-827-8839; Email: ucstudy@uci.edu
• Study Contact Backup: Name: University of California Irvine Medical

Study Locations

• United States
  • California
    • Orange, California, United States, 92868
      • Recruiting
      • Chao Family Comprehensive Cancer Center, University of California, Irvine
      • Contact: Maheswari Senthil, MD; Phone Number: 877-827-8839; Email: ucstudy@uci.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Cohort A: Patients must have histologically or cytologically confirmed primary gastric or gastroesophageal adenocarcinoma with a clinical diagnosis of metachronous PC with a history of prior gastric cancer resection. Extraperitoneal metastases are allowed.
• Cohort B: Patients must have histologically or cytologically confirmed primary colorectal or appendiceal adenocarcinoma with PC . Extraperitoneal metastases are allowed. Patients with PC amenable to cytoreductive surgery (CRS) without the need for upfront systemic therapy as determined by a peritoneal malignancy surgeon within 4 weeks prior to enrollment are excluded.
• Cohort C: Patients must have adenocarcinomas of the digestive tract with PC not included in Cohorts A and B (including but not limited to carcinomas of the small bowel and hepatobiliary tract).
• Must have peritoneal cytology positive disease or peritoneal carcinomatosis detected by imaging, laparoscopy or laparotomy
• Age ≥ 18
• Performance status: ECOG performance status ≤ 2 (Appendix A) . ECOG 2 allowed if attributed to malignancy (rather than comorbidities)
• Life expectancy of greater than 3 months
• Adequate organ and marrow function as defined below: Leukocytes: ≥ 2,000/mcL; Absolute neutrophil count: ≥ 1,500/mcL (may receive gcsf); Platelets: ≥ 70,000/mcl (may receive TPO); Total bilirubin: within 2x of normal institutional limit; AST(SGOT)/ALT(SPGT): ≤5 X institutional upper limit of normal; Creatinine: < 2 X institutional upper limit of normal; Hemoglobin: Hemoglobin > 8.0 g/dL (may be transfused); Serum albumin: ≥ 2.5 g/dL
• Ability to understand and the willingness to sign a written informed consent

Exclusion Criteria:

• Any evidence of small or large bowel obstruction with the exception of gastric outlet obstruction due to primary malignancy
• Uncontrolled intercurrent illness including, but not limited to, the following conditions: Ongoing or active infection; Symptomatic congestive heart failure; Stroke (including transient ischemic attack [TIA]), myocardial infarction (MI), or other ischemic event,) within 3 months before initiation of treatment; Unstable angina pectoris; Cardiac arrhythmia
• History of another primary cancer within the last 3 years with the exception of non-melanoma skin cancer, early-stage prostate cancer, or curatively treated cervical carcinoma in-situ and not treated with systemic therapy.
• History of prior iterative intraperitonealtherapy administered either as HIPEC, PIPAC or NIPEC. Single exposure to HIPEC at the time of cytreduction is not an exclusion
• Inability to comply with study and follow-up procedures as judged by the Investigator
• Patients must not be pregnant or nursing due to the potential for congenital abnormalities and the potential of this regimen to harm nursing infants.
• Women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry, for the duration of study participation, and for 90 days following completion of therapy. Should a woman become pregnant or suspect she is pregnant while participating in this study, she should inform her treating physician immediately.
• Has an active infection requiring systemic therapy.
• Prior surgery that would preclude safe diagnostic laparoscopy and port placement
• Has a known history of active tuberculosis (TB; Bacillus tuberculosis).
• Has a history or current evidence of any condition, therapy, or laboratory abnormality that might confound the results of the study, interfere with the participant's participation for the full duration of the study, or is not in the best interest of the participant to participate, in the opinion of the treating investigator.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

6

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: CohtAQ2W: Chort A Gastric/Esophageal Carcinoma (Paclitaxel Q2W)	Drug: Paclitaxel Q2W; Given IP-IV, every 2 weeks
Experimental: CohtAQ3W: Cohort A Gastric/Esophageal Carcinoma (Paclitaxel Q3W)	Drug: Paclitaxcel Q3W; Given IP-IV, every 3 weeks
Experimental: CohtBQ2W: Cohort B Colorectal/Appendiceal Adenocarcinoma (Paclitaxel Q2W)	Drug: Paclitaxel Q2W; Given IP-IV, every 2 weeks
Experimental: CohtBQ3W: Cohort B Colorectal/Appendiceal Adenocarcinoma (Paclitaxel Q3W)	Drug: Paclitaxcel Q3W; Given IP-IV, every 3 weeks
Experimental: CohtCQ2W: Cohort C Other Malignancies of the Digestive Tract (Paclitaxel Q2W)	Drug: Paclitaxel Q2W; Given IP-IV, every 2 weeks
Experimental: CohtCQ3W: Cohort C Other Malignancies of the Digestive Tract (Paclitaxel Q3W)	Drug: Paclitaxcel Q3W; Given IP-IV, every 3 weeks

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Protocol Treatment Completion Rate	Number of patients that complete treatment at 2 cycles	6 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Overall Survival of Participants	To assess the overall survival of participants from the start of systemic treatment to the death from any cause.	3 years
Participants with Progression Free Survival	Progression-free survival is defined as the duration of time from start of systemic treatment to time of progression, death, or clinical deterioration attributed to disease progression as judged by the investigator. Radiographic progression is defined using the Response Evaluation Criteria in Solid Tumors Criteria (RECIST v1.1) as a 20% increase in the sum of diameters of target lesions and an absolute increase of at least 5 mm and/or appearance of new lesions.	3 years
Patient Reported Quality of Life Outcomes	To assess the quality of life of participants such as mobility, self-care, daily activities, pain/discomfort and anxiety/depression and a visual analog scale (VAS). VAS consists of endpoints labeled best imaginable health status at the top and worse imaginable health state at the bottom having numeric values of 100 and 0 respectively.	1 year
Incidence of Treatment-Emergent Adverse Events [Safety]	To evaluate the safety of IP paclitaxel and IV paclitaxel, 5-FU, and leucovorin in patients with primary gastric/GEJ adenocarinoma with peritoneal carcinomatosis determined by the incidence of treatment-emergent adverse events. Adverse events are based on the CTCAE (NCI Common Terminology Criteria for Adverse Events) Version 5.0.	1 year
Overall Response Rate (ORR) by RECIST v1.1	Sum of Complete Response (CR) and Partial Response (PR) by RECIST v1.1. Per Response Evaluation Criteria in Solid Tumors (RECIST v1.1): Complete Response (CR) is defined as the disappearance of all target lesions; Partial Response (PR) is defined as a 30% decrease in the sum of diameters of target lesions. ORR = CR + PR	1 year

Collaborators and Investigators

• Sponsor: University of California, Irvine
• Investigators: Principal Investigator: Maheswari Senthil, MD, Chao Family Comprehensive Cancer Center

Study record dates

Study Major Dates

• Study Start (Actual): August 4, 2026
• Primary Completion (Estimated): August 31, 2029
• Study Completion (Estimated): August 31, 2029

Study Registration Dates

• First Submitted: August 26, 2026
• First Submitted That Met QC Criteria: August 26, 2026
• First Posted (Actual): August 31, 2026

Study Record Updates

• Last Update Posted (Actual): August 31, 2026
• Last Update Submitted That Met QC Criteria: August 26, 2026
• Last Verified: August 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Neoplasms by Site; Neoplasms; Neoplasms by Histologic Type; Gastrointestinal Neoplasms; Digestive System Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Stomach Diseases; Head and Neck Neoplasms; Neoplasms, Glandular and Epithelial; Adenocarcinoma; Esophageal Diseases; Carcinoma; Neoplasms, Cystic, Mucinous, and Serous; Pathological Conditions, Signs and Symptoms; Stomach Neoplasms; Esophageal Neoplasms; Disease; Adenocarcinoma, Mucinous
• Other Study ID Numbers: STUDY00001075; UCI 25-190 (Other Identifier: UCI CFCCC)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: Yes