(PLASTIC-3) [18F]FAPI-PET/CT and Laparoscopy in STagIng advanced gastric Cancer – a multicenter prospective study

Overview

Sponsor-declared trial summary

Key facts

Sponsor

Leids Universitair Medisch Centrum (LUMC)

Participant type

Patients

Age range

18-64 years

Gender

Male and Female

Therapeutic area

Diseases [C] - Neoplasms [C04], Analytical, Diagnostic and Therapeutic Techniques and Equipment [E] - Diagnosis [E01], Diseases [C] - Digestive System Diseases [C06]

Trial duration

3 Jul 2025 → ongoing

Decision date (initial)

2025-05-06

Transition trial

No

Low-intervention

No

Rare-disease indication

No

Vulnerable population

No

Funding sources

Dutch Cancer Society - Koningin Wilhelmina Fonds (KWF) voor kankerbestrijding

Trial design

CTIS Part I — objectives, methods, condition coding

Main objective

Scope: Diagnosis

To assess the applicability and impact of [18F]AlF-FAPI-74 PET/CT as a non-invasive imaging biomarker to optimize whole body staging of locally advanced gastric cancer, limiting the need for staging laparoscopy

Secondary objectives 10

1. To assess the diagnostic performance of [18F]AlF-FAPI-74 PET/CT, as compared to CT and staging laparoscopy, to detect M1- disease
2. To determine the occurrence and impact of incidental and/or non-specific findings on [18F]AlF-FAPI-74 PET/CT
3. To assess the diagnostic time delay occurring due to this extra investigation ([18F]AlF-FAPI-74 PET/CT)
4. To contribute to safety data regarding the clinical use of [18F]AlF-FAPI-74 PET/CT
5. To evaluate (on PCI regional level) the region based accuracy (sensitivity and specificity) between 18F]AlF FAPI 74 PET based PCI scores and staging laparoscopy based PCI scores
6. To establish a quantitative correlation between PCI-regional FAPI uptake and PCI-regional histopathological tumor scores, with the aim of developing a standardized, non-invasive method for PCI evaluation in the future
7. To assess the agreement between TSR and CAF-specific FAP expression determined on the diagnostic pre-operative tumor biopsies (D1D2 and CRITICS studies)
8. To assess the correlation between TSR/FAP expression and uptake on [18F]AlF-FAPI-74 PET/CT in tissue specimens collected in WP1 and 2.
9. To assess the characteristics of FAP expressing CAF subsets
10. A trial-based cost-effectiveness analysis will be conducted to calculate the incremental cost-effectiveness ratio (ICER) of [18F]AlF-FAPI-74 PET/CT compared with staging laparoscopy in the Dutch situation in case of sufficient diagnostic performance

Conditions and MedDRA coding

Advanced gastric cancer

Eligibility criteria

Principal inclusion / exclusion criteria as submitted by sponsor

Inclusion criteria 5

1. Histologically proven adenocarcinoma of the stomach or the esophagogastric junction (Siewert type III), by gastroscopy
2. Age greater than or equal to 18 years
3. Surgically resectable, advanced tumor (cT3-4b, N0-3, M0), as determined on gastroscopy and a contrast-enhanced CT of thorax and abdomen. Intention to perform a gastrectomy, based on a multidisciplinary team meeting and shared decision making
4. Patients must have given written informed consent
5. Patients who have recently participated in an interventional study with an investigational medicinal product (IMP) may only participate if an interaction with study procedures is deemed unlikely by the study team (e.g. based on mechanism or washout period)

Exclusion criteria 8

1. Siewert type I-II esophagogastric junction tumor
2. Unfit or unwilling to undergo study procedures
3. Unfit or unwilling to undergo surgery
4. Pregnancy at time of the [18F]AlF-FAPI-74 PET/CT scan, due to the investigational PET radiation burden
5. Incapacitated subjects without decision-making capacity
6. Medical or psychiatric conditions that compromise the patient’s ability to give informed consent
7. Illiterate patients unable to complete the resource use and quality of life questionnaires
8. Inability to undergo PET/CT scans due to factors such as claustrophobia, weight limits, or the inability to lie flat for the duration of the scan (approximately 30 minutes)

Endpoints

Primary and secondary outcome measures (English text)

Primary endpoints 2

1. Proportion of patients in whom [18F]AlF-FAPI-74 PET/CT leads to detection of M1-disease resulting in change in treatment intent determined by the local multidisciplinary team (MDT) meetings, including: the number of prevented unnecessary surgeries (staging laparoscopies and/or gastrectomies) and the number of changes from curative to palliative treatment
2. Proportion of patients in whom [18F]AlF-FAPI-74 PET/CT leads to changes in diagnostic work-up determined by the local MDT meetings, including: the number of additional biopsies or longitudinal imaging and the number of changes in extent of surgery

Secondary endpoints 13

1. Diagnostic performance measured in sensitivity, specificity, diagnostic accuracy, positive predictive value and negative predictive value using histopathologic tumor tissue collected during biopsy, staging laparoscopy and follow-up imaging as refence test
2. Proportion of patients with relevant incidental findings (e.g. second primary tumors)
3. Patients’ extra burden of undergoing additional diagnostics due to incidental and/or non-specific [18F]AlF-FAPI-74 PET/CT findings using EORTC-QLQ-C30, EQ-5D-5L, and patient reported experience measure (PREM) questionnaires (section 6.1)
4. Time between pre-diagnostic and post-diagnostic MDT meetings
5. The occurrence, type, and severity of (serious) adverse events
6. Correlation between 18F]AlF FAPI 74 PET based Peritoneal Cancer Index (PCI) scores and staging laparoscopy based PCI scores as a reference standard for ‘true’ intraperitoneal tumor load
7. Correlation between PCI-regional FAPI uptake and PCI-regional histopathological tumor scores
8. Expression of CAF content as measured by tumor-stroma ratio (TSR) on tissue samples from D1D2/CRITICS and relation with FAP expression.
9. Analysis of TSR and FAP expression and correlation to [18F]AlF-FAPI-74 PET/CT signal
10. Analysis of all FAP expressing CAF subsets in obtained patient samples using imaging mass cytometry
11. Patient burden using a developed patient reported experience measure (PREM) questionnaire
12. Quality of life as measured using the EORTC-QLQ-C30 and EQ-5D5L questionnaires and compared to PLASTIC
13. Costs of [18F]AlF- FAPI-74 PET/CT compared with staging laparoscopy compared to PLASTIC for patients who received SL only, using the SL bottom-costing approach numbers from the PLASTIC-cost analysis study

Investigational products

Investigational medicinal products (IMPs), comparators, placebo, auxiliary

Test 1

Sponsors and contacts

Sponsor organisations, regulatory contacts, third parties

Leids Universitair Medisch Centrum (LUMC)

Sponsor organisation

Leids Universitair Medisch Centrum (LUMC)

Address

Albinusdreef 2

City

Leiden

Postcode

2333 ZA

Country

Netherlands

Scientific contact point

Organisation

Leids Universitair Medisch Centrum (LUMC)

Contact name

Department of Radiology (Nuclear Medicine)

Public contact point

Organisation

Leids Universitair Medisch Centrum (LUMC)

Contact name

Department of Radiology (Nuclear Medicine)

Locations

1 EU/EEA country · 12 investigational sites

By country

Investigational sites

Country notifications

Trial-start, recruitment-start, end and early-termination notifications submitted per Member State

Results and documents

Annex IV summary of results, Annex V layperson summary, and all documents registered in CTIS for this trial

Documents 9 files

Public protocol annexes, IB summaries, regulatory submissions and post-authorisation documents registered in CTIS.

Application history

3 submissions — initial application plus substantial / non-substantial modifications