Exploratory Clinical Study of ¹⁷⁷Lu-CTR-FAPI in Patients With Metastatic Solid Tumors

An Exploratory Clinical Study Evaluating the Safety, Tolerability, and Preliminary Efficacy of ¹⁷⁷Lu-CTR-FAPI in Patients With Metastatic Solid Tumors

This is a single-center, non-randomized, single-arm, open-label exploratory clinical study of ¹⁷⁷Lu-CTR-FAPI in patients with FAP-high expressing metastatic solid tumors, with a focus on breast cancer, sarcoma, and thyroid cancer.

The purpose of this study is to evaluate the safety and tolerability of ¹⁷⁷Lu-CTR-FAPI. The study will also assess its in vivo biodistribution, radiation absorbed dose in normal organs and target lesions, and preliminary clinical efficacy.

The main question this study aims to answer is whether ¹⁷⁷Lu-CTR-FAPI can be administered safely and shows sufficient tumor-targeting and preliminary therapeutic activity to support further clinical investigation in patients with FAP-high expressing metastatic solid tumors.

Study Overview

• Status: Completed
• Conditions: Metastatic Solid Tumors (Any Localization)
• Intervention / Treatment: Drug: radionuclide therapy with ¹⁷⁷Lu-CTR-FAPI

Detailed Description

This is an investigator-initiated, single-center, non-randomized, single-arm, open-label exploratory clinical trial of ¹⁷⁷Lu-CTR-FAPI in patients with FAP-high expressing metastatic solid tumors.

Participants will receive ¹⁷⁷Lu-CTR-FAPI by intravenous infusion. The planned standard activity is 200 mCi (7.4 GBq) ±10%, administered every 6±1 weeks for up to 4 cycles. Dose reduction to 100 mCi (3.7 GBq) may be performed according to predefined toxicity criteria.

During the first treatment cycle, participants will undergo intensive blood sampling and serial imaging to evaluate biodistribution and radiation dosimetry. Whole-body planar imaging and localized quantitative SPECT/CT will be performed at multiple time points from approximately 1 hour to 7-9 days after the initial administration. Regions of interest will be drawn for source organs and target lesions, and time-activity curves will be generated to estimate cumulative activity. Absorbed doses to normal organs and tumor lesions will be calculated using OLINDA/EXM software.

Safety will be monitored throughout the study by vital signs, physical examinations, laboratory tests, 12-lead electrocardiograms, and adverse event recording. Adverse events will be coded and graded according to CTCAE v5.0, with particular attention to hematologic, hepatic, and renal toxicities.

Tumor imaging evaluations will be performed according to the study schedule. Preliminary efficacy will be assessed using RECIST 1.1, including objective response rate and progression-free survival. Statistical analyses will be descriptive, and missing data will not be imputed.

• Study Type: Interventional
• Enrollment (Actual): 12
• Phase: Early Phase 1

Contacts and Locations

Study Locations

• China
  • Gansu
    • Lanzhou, Gansu, China, 730000
      • The Second Hospital & Clinical Medical School, Lanzhou University

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Pathological diagnosis confirmed metastatic solid tumors (breast cancer, sarcoma, and some thyroid cancers, etc.) that failed standard treatment or lacked standard treatment
• Age: 75 ≥ age ≥ 18 years
• ECOG score: 0 - 2
• 68Ga-CTR-FAPI PET/CT confirmed high expression of FAP in the tumor (more than 50% of the lesions with SUVmax ≥ 10)
• The FAP immunohistochemical score of tumor cells is ≥ 2 (except for thyroid cancer)
• There is at least one measurable lesion (RECIST 1.1)
• Organ/marrow functions meet the specified thresholds, and there are no severe electrocardiogram abnormalities (QTcF ≤ 470ms)

Exclusion Criteria:

• There is brain metastasis or other central nervous system lesions.
• The expected survival period is less than 6 months.
• Within 4 weeks before administration, the patient has received chemotherapy, targeted therapy, immunotherapy, or other anti-tumor treatments or investigational drugs.
• The patient has previously received other systemic radionuclide therapy (excluding 131I treatment for thyroid cancer).
• There is uncontrolled pleural effusion, ascites, severe cardiovascular or cerebrovascular diseases, or infection.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Patients with advanced metastatic solid tumors	Drug: radionuclide therapy with ¹⁷⁷Lu-CTR-FAPI; a novel covalent targeted radioligand (CTR), ¹⁷⁷Lu-CTR-FAPI, utilizing a sulfur(VI) fluoride exchange (SuFEx) click chemistry-based strategy

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants With Treatment-Emergent Adverse Events	Number of participants with treatment-emergent adverse events, serious adverse events, and adverse events leading to treatment discontinuation. Adverse events will be coded and graded according to the Common Terminology Criteria for Adverse Events version 5.0.	From first administration of [¹⁷⁷Lu]Lu-CTR-FAPI through 6 weeks after the last administration
Number of Participants With Abnormal Vital Signs	Number of participants with clinically significant abnormal vital signs, including systolic blood pressure, diastolic blood pressure, heart rate, respiratory rate, body temperature, and oxygen saturation, as determined by the investigator.	From first administration of [¹⁷⁷Lu]Lu-CTR-FAPI through 6 weeks after the last administration
Number of Participants With Abnormal Laboratory Test Results	Number of participants with clinically significant abnormal laboratory test results, including complete blood count, liver function tests, renal function tests, and serum electrolytes, graded according to the Common Terminology Criteria for Adverse Events version 5.0 when applicable.	From first administration of [¹⁷⁷Lu]Lu-CTR-FAPI through 6 weeks after the last administration

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Objective Response Rate	Objective response rate is defined as the proportion of participants with a best overall response of complete response or partial response according to RECIST version 1.1.	Every 8 weeks from baseline until disease progression, initiation of new anticancer therapy, withdrawal, death, or study completion, up to 12 months
Progression-Free Survival	Progression-free survival is defined as the time from the first administration of [¹⁷⁷Lu]Lu-CTR-FAPI to the first documented disease progression according to RECIST version 1.1 or death from any cause, whichever occurs first.	From first administration of [¹⁷⁷Lu]Lu-CTR-FAPI until disease progression or death, up to 12 months
Radiation dosimetry	Through whole-body planar imaging, local SPECT/CT quantitative tomographic imaging combined with blood sample determination, the radiation absorption doses of normal organs and target lesions were calculated using the OLINDA/EXM software.	It should be measured within 1 hour to 7 to 9 days after the first administration of the drug.

Collaborators and Investigators

• Sponsor: Lanzhou University Second Hospital

Study record dates

Study Major Dates

• Study Start (Actual): November 20, 2024
• Primary Completion (Actual): March 20, 2026
• Study Completion (Actual): April 20, 2026

Study Registration Dates

• First Submitted: May 2, 2026
• First Submitted That Met QC Criteria: May 8, 2026
• First Posted (Actual): May 14, 2026

Study Record Updates

• Last Update Posted (Actual): May 14, 2026
• Last Update Submitted That Met QC Criteria: May 8, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: 2024A-1337

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