RecruitingPhase 1/2

A Study of ASP546C in Adults With Gastroesophageal Cancer, Pancreatic Cancer or Other Solid Tumors

United States150 participantsStarted 2026-03-20

Plain-language summary

This study will help find the most suitable dose of ASP546C in people with gastric cancer, gastroesophageal junction (GEJ) cancer, pancreatic cancer, and other specific solid tumors. GEJ is where the food pipe (esophagus) joins the stomach. This study is in 2 parts. In both parts of the study, ASP546C will be given once in 3-week cycles. It will be given slowly through a tube into a vein. This is called an infusion. In Part 1, people with gastric cancer or GEJ cancer can take part. They will receive an infusion of either a higher dose or a lower dose of ASP546C. In Part 2, people with pancreatic cancer or who have one of the other solid tumors can take part. Part 2 doesn't include people with gastric cancer or GEJ cancer. All people in this part of the study will receive an infusion of the higher dose of ASP546C. People will visit the clinic on certain days to receive ASP546C and have health checks. The number of visits and checks done during the study will depend on the health of each person and whether they are still receiving infusions of ASP546C.

Who can participate

Age range18 Years

SexALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Participant has a histologically confirmed diagnosis of gastroesophageal (gastric/GEJ/esophageal) adenocarcinoma, pancreatic adenocarcinoma, or pan-tumor (cholangiocarcinoma, colorectal adenocarcinoma, NSCLC \[adenocarcinoma\], SCLC, ovarian mucinous carcinoma or invasive breast cancer \[ER/PR+HER2-; ER/PR-HER2+; ER/PR+HER2+ (triple positive); ER/PR-HER2- (triple negative)\]. * Participant has radiologically confirmed uLA/m gastroesophageal (gastric/GEJ/esophageal) adenocarcinoma, pancreatic adenocarcinoma or pan-tumor within 28 days prior to the first dose of study intervention. * Cohorts 1 to 3 only: Participant has measurable disease according to RECIST v1.1 within 28 days prior to the first dose of study intervention. For participants with only 1 measurable lesion and prior radiotherapy, the lesion must be outside the field of prior radiotherapy or must have documented progression following radiation therapy. * Cohort 4 only: Participant has radiologically evaluable disease (measurable and/or non-measurable) according to RECIST v1.1, within 28 days prior to the first dose of study intervention. For participants with only 1 evaluable lesion and prior radiotherapy, the lesion must be outside the field of prior radiotherapy or must have documented progression following radiation therapy. * Participant's tumor expresses CLDN18.2. * Participant has received at least 1 line of therapy for uLA/m disease. * Participant has an ECOG performance status of 0 or…

What they're measuring

Part 1: Objective Response Rate (ORR) per Investigator-assessed per Response Evaluation Criteria in Solid Tumors (RECIST) v1.1

Timeframe: Up to 36 Months

Part 1: Pharmacokinetics (PK) of ASP546C Antibody-drug Conjugate (ADC): Serum Concentrations of Antibody-drug Conjugate

Timeframe: Up to 39 Months

Part 1: PK of ASP546C ADC: Maximum Concentration (Cmax)

Timeframe: Up to 39 Months

Part 1: PK of ASP546C ADC: Area Under the Serum Concentration-time Curve from Time Zero to 21Days (AUC0-21d)

Timeframe: Up to 39 Months

Part 1: Number of participants with Adverse events (AEs)

Timeframe: Up to 39 Months

Part 1: Number of Participants with Vital Sign Abnormalities and/or AEs

Timeframe: Up to 39 Months

Part 1: Number of Participants with Laboratory Value Abnormalities and/or AEs

Timeframe: Up to 39 Months

Trial details

NCT IDNCT07488676

SponsorAstellas Pharma Global Development, Inc.

Sponsor typeINDUSTRY

Study typeINTERVENTIONAL

Primary completion2029-07-31

Contact for this trial

Astellas Pharma Global Development, Inc

800-888-7704 Astellas.registration@astellas.com

View on ClinicalTrials.gov More Gastric or Gastro-esophageal Junction (GEJ) Adenocarcinoma trials

Plain-language summary

Who can participate

Age range18 Years

SexALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

What they're measuring

Part 1: Objective Response Rate (ORR) per Investigator-assessed per Response Evaluation Criteria in Solid Tumors (RECIST) v1.1

Timeframe: Up to 36 Months

Part 1: Pharmacokinetics (PK) of ASP546C Antibody-drug Conjugate (ADC): Serum Concentrations of Antibody-drug Conjugate

Timeframe: Up to 39 Months

Part 1: PK of ASP546C ADC: Maximum Concentration (Cmax)

Timeframe: Up to 39 Months

Part 1: PK of ASP546C ADC: Area Under the Serum Concentration-time Curve from Time Zero to 21Days (AUC0-21d)

Timeframe: Up to 39 Months

Part 1: Number of participants with Adverse events (AEs)

Timeframe: Up to 39 Months

Part 1: Number of Participants with Vital Sign Abnormalities and/or AEs

Timeframe: Up to 39 Months

Part 1: Number of Participants with Laboratory Value Abnormalities and/or AEs

Timeframe: Up to 39 Months