A Study of SGN-MesoC2 in Advanced Solid Tumors

A PHASE 1 OPEN-LABEL, MULTICENTER STUDY TO EVALUATE THE SAFETY, TOLERABILITY, PHARMACOKINETICS, AND ANTITUMOR ACTIVITY OF PF-08052666/SGN-MESOC2 IN PARTICIPANTS WITH ADVANCED SOLID TUMORS

This clinical trial is studying advanced solid tumors. Solid tumors are cancers that start in a part of your body like your lungs or liver instead of your blood. Once tumors have grown bigger in one place but haven't spread, they're called locally advanced. If your cancer has spread to other parts of your body, it's called metastatic. When a cancer has gotten so big it can't easily be removed or has spread to other parts of the body, it is called unresectable. These types of cancer are harder to treat.

Patients in this study must have cancer that has come back or did not get better with treatment. Patients must have a solid tumor cancer that can't be treated with standard of care drugs.

This clinical trial uses an experimental drug called PF-08052666/SGN-MesoC2. PF-08052666/SGN-MesoC2 is a type of antibody-drug conjugate (ADC). ADCs are designed to stick to cancer cells and kill them. They may also stick to some normal cells.

This study will have 3 parts. Part A and Part B of the study will find out how much PF-08052666/SGN-MesoC2 should be given to participants. Part C will use the information from Parts A and B to see if PF-08052666/SGN-MesoC2 is safe and if it works to treat solid tumor cancers.

Study Overview

• Status: Terminated
• Conditions: Carcinoma, Non-Small-Cell Lung; Colorectal Neoplasms; Pancreatic Adenocarcinoma; Ovarian Neoplasms; Mesothelioma; Other Solid Tumors; Endometrial
• Intervention / Treatment: Drug: PF-08052666

• Study Type: Interventional
• Enrollment (Actual): 19
• Phase: Phase 1

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Toronto, Ontario, Canada, M5G 2C4
      • University Health Network
    • Toronto, Ontario, Canada, M5G 2M9
      • University Health Network, Princess Margaret Cancer Centre
  • Quebec
    • Montreal, Quebec, Canada, H4A 3J1
      • McGill University Health Centre
• United States
  • Alabama
    • Birmingham, Alabama, United States, 35233
      • University of Alabama at Birmingham
    • Birmingham, Alabama, United States, 35249
      • University of Alabama at Birmingham
    • Birmingham, Alabama, United States, 35249
      • The University of Alabama at Birmingham
    • Birmingham, Alabama, United States, 35294
      • The Board of Trustees of the University of Alabama for the University of Alabama at Birmingham
  • Kansas
    • Fairway, Kansas, United States, 66205
      • The University of Kansas Clinical Research Center
    • Kansas City, Kansas, United States, 66160
      • The University of Kansas Hospital
    • Kansas City, Kansas, United States, 66160
      • The University of Kansas Medical Center Medical Office Building
    • Kansas City, Kansas, United States, 66160
      • The University of Kansas Hospital Cambridge North Tower A
    • Overland Park, Kansas, United States, 66211
      • The University of Kansas Cancer Center - Indian Creek Campus
    • Westwood, Kansas, United States, 66205
      • The University of Kansas Cancer Center, Investigational Drug Services
    • Westwood, Kansas, United States, 66205
      • The University of Kansas Cancer Center - Westwood
  • North Carolina
    • Winston-Salem, North Carolina, United States, 27157
      • Atrium Health Wake Forest Baptist
  • Tennessee
    • Nashville, Tennessee, United States, 37203
      • Sarah Cannon Research Institute - Pharmacy
    • Nashville, Tennessee, United States, 37203
      • SCRI Oncology Partners
  • Texas
    • San Antonio, Texas, United States, 78229
      • START San Antonio, LLC
  • Utah
    • West Valley City, Utah, United States, 84119
      • START Mountain Region, LLC

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Aged 18 years or older.
• Histologically- or cytologically-confirmed metastatic or locally advanced unresectable platinum-resistant ovarian cancer, NSCLC, pancreatic ductal adenocarcinoma, endometrial cancer, colorectal cancer, or mesothelioma, who have relapsed or progressed following standard therapies, or for which no standard therapies are available.
• An Eastern Cooperative Oncology Group performance status score of 0 or 1.
• At least 1 measurable lesion at baseline based on Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST v1.1).
• Archival tumor tissue or a fresh tumor biopsy during the screening period.
• Adequate hepatic, renal and bone marrow function.
• Participants must not have received more than 2 lines of cytotoxic systemic therapy in the metastatic setting (Parts B and C only).

Exclusion Criteria:

• Previously received or currently receiving any systemic anticancer therapy or focal radiotherapy within 4 weeks prior to the first dose of MesoC2 or within 2 weeks prior to the first dose of MesoC2 if the underlying disease had progressed on treatment.
• Prior anti-MSLN antibody or MSLN-directed ADC (Part C only).
• Unresolved toxicities from prior therapy greater than NCI CTCAE v5.0 grade 1 at the time of study treatment (except alopecia).
• Inadequate hepatic dysfunction, renal function, or hematologic abnormalities.
• Previously untreated brain metastases. Participants who received radiation or surgery for brain metastases are eligible if therapy was completed at least 4 weeks prior to study treatment initiation, and there was no evidence of central nervous system progression nor requirements for chronic corticosteroid therapy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: PF-08052666; PF-08052666 monotherapy	Drug: PF-08052666; Given into the vein (IV; intravenously); Other Names: HBM9033; SGN-MesoC2

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of participants with adverse events (AEs)	An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention.	Through 30-37 days after the last dose of study treatment, 48 Months
Number of participants with laboratory abnormalities		Through 30-37 days after the last dose of study treatment, 48 Months
Number of participants with dose modifications	Frequency of dose modifications (eg, dose delay, treatment interruptions, dose reductions and treatment discontinuations) due to AEs	Up to 4 months
Number of participants with dose-limiting toxicities (DLTs)	Incidence of dose-limiting toxicities (DLTs)	Cycle 1 (21 days)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Objective response rate (ORR)	ORR is defined as the proportion of participants in the relevant analysis set with best response of complete response (CR) or partial response (PR) according to Response Evaluation Criteria in Solid Tumors (RECIST) v1.1.	Approximately 1 year 4 months
Best response	The best timepoint response achieved for the subject during the protocol specified period according to RECIST V1.1.	Approximately 1 year 4 months
Duration of response (DOR)	DOR is defined as the time interval from first occurrence of documented objective response to the time of progressive disease (PD) according to RECIST v1.1 or death from any cause, whichever comes first.	Approximately 1 year 4 months
Disease control rate (DCR)	DCR is defined as the proportion of participants with best response of CR, PR or stable disease (SD) according to RECIST v1.1.	Approximately 1 year 4 months
Progression-free survival (PFS)	PFS is defined as the time from first dosing to the first occurrence of PD according to RECIST v1.1 or death from any cause, whichever comes first.	Approximately 1 year 4 months
Overall survival (OS)	Overall survival (OS) defined as the time from first dosing to death.	Approximately 1 year 4 months
Pharmacokinetic (PK) parameter - Area under the serum concentration (AUC)		Cycles 1, 2, and 3 (each cycle is up to 21 days)
Pharmacokinetic (PK) parameter - Maximum serum concentration (Cmax)		Cycles 1, 2, and 3 (each cycle is up to 21 days)
Pharmacokinetic (PK) parameter - Time to reach maximum serum concentration (Tmax)		Cycles 1, 2, and 3 (each cycle is up to 21 days)
Pharmacokinetic (PK) parameter - Half-life		Cycles 1, 2, and 3 (each cycle is up to 21 days)
Number of participants with antidrug antibodies		Cycles 1, 2, and 3 (each cycle is up to 21 days)

Collaborators and Investigators

• Sponsor: Seagen, a wholly owned subsidiary of Pfizer
• Investigators: Study Director: Pfizer CT.gov Call Center, Pfizer

Publications and helpful links

Helpful Links

• To obtain contact information for a study center near you, click here.

Study record dates

Study Major Dates

• Study Start (Actual): August 2, 2024
• Primary Completion (Actual): May 27, 2026
• Study Completion (Actual): May 27, 2026

Study Registration Dates

• First Submitted: June 11, 2024
• First Submitted That Met QC Criteria: June 17, 2024
• First Posted (Actual): June 20, 2024

Study Record Updates

• Last Update Posted (Actual): July 7, 2026
• Last Update Submitted That Met QC Criteria: July 6, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Colorectal Cancer; Ovarian Cancer; Seattle Genetics; Endometrial; Lung Neoplasm; Colorectal Tumors; NSCL; Cancer of Ovary
• Additional Relevant MeSH Terms: Urogenital Diseases; Genital Diseases; Endocrine System Diseases; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Intestinal Diseases; Respiratory Tract Diseases; Neoplasms by Histologic Type; Gastrointestinal Neoplasms; Digestive System Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Intestinal Neoplasms; Rectal Diseases; Genital Diseases, Female; Lung Diseases; Endocrine Gland Neoplasms; Neoplasms, Glandular and Epithelial; Respiratory Tract Neoplasms; Thoracic Neoplasms; Colonic Diseases; Ovarian Diseases; Adnexal Diseases; Genital Neoplasms, Female; Gonadal Disorders; Adenoma; Neoplasms, Mesothelial; Carcinoma, Bronchogenic; Bronchial Neoplasms; Lung Neoplasms; Colorectal Neoplasms; Ovarian Neoplasms; Mesothelioma; Carcinoma, Non-Small-Cell Lung
• Other Study ID Numbers: C5991001 (Pfizer); SGNMesoC2-001 (Other Identifier: Alias Study Number)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical_trials/trial_data_and_results/data_requests.

Drug and device information, study documents

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