Overview

The goal of this clinical trial is to investigate the use of the tracer [68Ga]Ga-FAPI-46 for PET/CT-imaging in response evaluation of patients with advanced stage malignant melanoma treated with immune checkpoint inhibitor therapy (ICT). The main question it aims to answer is:

• Can [68Ga]Ga-FAPI-46 PET/CT improve response evaluation in patients suffering from advanced stage malignant melanoma treated with ICT and potentially serve as a biomarker.

Researchers will compare findings on the experimental [68Ga]Ga-FAPI-46 PET/CT with findings on standard imaging ([18F]FDG PET/CT).

Participants will undergo:

• Two [68Ga]Ga-FAPI-46 PET/CT scans: one before treatment initiation with ICT and one after three months.
• Two blood samples
• Passive follow-up 6 months after the last scan [68Ga]Ga-FAPI-46 PET/CT

Eligibility

Inclusion Criteria:

1. Male or female, >/=18 years old
2. Histological verified metastatic or locally advanced malignant melanoma
3. Visible malignant lesions on [18F]FDG PET/CT or CT
4. Subjects must be considered inoperable
5. Subjects must be considered medically suitable for ICT
6. Subjects must be able to read and understand the patient information in Danish to give informed consent

Exclusion Criteria:

1. Ocular or mucosal melanoma
2. Other concurrent cancer disease
3. Previous systemic oncological treatment with ICT
4. Pregnancy or lactation
5. Weight more than the maximum limit of a PET/CT-scanner bed (140 kg)
6. History of allergic reaction due to compounds similar to the chemical composition of [68Ga]Ga-FAPI- 46