Pseudovav - A Cancer Vaccine Targeting Mutated GNAS Combined With Immune Checkpoint Inhibition for Patienes With Pseudomyxoma Peritonei
Participants will receive vaccination with Pseudovax/GM-CSF in combination with PD-1 inhibitor tislelizumab over a period of up to two years. The vaccine is expected to reactivate measurable immune response, and tislelizumab to restore anticancer immunity in patients with GNAS mutated pseudomyxoma peritonei.
• The subject is ≥ 18 years of age on the day of signing the informed consent form, able to provide written informed consent and can understand and agree to comply with the requirements of the study and the schedule of assessments.
• Confirmed diagnosis of recurrent or non-resectable PMP with no other available treatment options that are expected to be efficacious.
• The subject's tumor must carry a mutation in the GNAS oncogene\*
• Subjects must have peritoneal tumor distribution at screening that, in the opinion of the Investigator, is suitable for repeat biopsies: Up to 3 biopsies of target tissue are planned for subjects that complete the study.
• Adequate organ, bone marrow, liver, and renal function at screening, including:
‣ Absolute neutrophil count: ≥ 1,5 x109/L
⁃ Platelets: ≥ 100 x109/L
⁃ Hemoglobin: ≥ 9 x109/L
⁃ Creatinine ≤ 1,5 upper limit normal (ULN) OR measured/calculated GFR ≥60 mL/min
⁃ Albumin ≥ 30 g/L
⁃ Total bilirubin ≤ 1,5 ULN
⁃ ASAT and ALAT ≤ 3 ULN
⁃ International Normalized Ratio (INR) ≤ 1,5 ULN and Activated Partial Thromboplastin Time (aPTT) ≤ 1,5 ULN unless subject is receiving anticoagulant therapy.
• ECOG performance status of 0 or 1.
• Life expectancy of \>6 months, at the time of signing the informed consent.
• Women of childbearing potential must have a negative serum pregnancy test within 48 hours of the first study intervention, and must not be breast-feeding. 8ai. Female participant:
• i. Unless documented not to have childbearing potential: Subject is willing to use contraceptive measures for the duration of the study, and ≥ 6 months after the last dose of IMP, as prescribed by the protocol (according to the applicable guidance: CTFG, 2020). The Investigator should counsel women of childbearing potential of the importance of pregnancy prevention.
∙ 8aii. Women of childbearing potential must have a negative serum pregnancy test within 48 hours of the first study intervention.
∙ 8b. Male subject: Sexually active males must be willing to use a condom during sex for the duration of the study and for ≥ 6 months after the last dose of IMP. Males must also be willing to abstain from donating sperm during the same period.