Metformin in Pseudomyxoma Peritonei Secondary to Appendiceal Mucinous Neoplasms

The film gives the main points. The full list below is copied from the registry; the study team makes the final decision.

• Age18 Years to no maximum
• SexAll
• Healthy volunteersNo

You may be able to join if

• Key Inclusion Criteria (complete details available in protocol):
• Patients with clinical diagnosis of pseudomyxoma peritonei (PMP) secondary to presumed appendiceal mucinous neoplasms (AMNs) with recurrent/refractory disease s/p cytoreductive surgery(CRS)/hyperthermic intraperitoneal chemotherapy (HIPEC), unresectable disease, or without planned CRS/HIPEC
• Age ≥18 years
• ECOG performance status ≤2
• Key Exclusion Criteria (complete details available in protocol):
• Patients with a clinical diagnosis of PMP secondary to presumed AMNs with resectable disease who are planned to undergo CRS/HIPEC
• Patients currently taking metformin for another medical indication
• Patients with a prior adverse event to administration of metformin

This is how the treatment is meant to work. Whether it helps, and how safe it is, is what this trial is testing.

extended release metformin hydrochloride. An extended-release (ER) tablet composed of the hydrochloride salt form of the biguanide metformin, with antihyperglycemic and potential prostate-cancer protective and antineoplastic activities. Upon oral administration, metformin targets and inhibits complex I (NADPH:ubiquinone oxidoreductase) of the mitochondrial respiratory chain and increases the cellular adenosine monophosphate (AMP) to adenosine triphosphate (ATP) ratio leading to activation of AMP-activated protein kinase (AMPK). This modulates AMPK-mediated transcription of target genes, which prevents hepatic gluconeogenesis, decreases intestinal absorption of glucose, enhances insulin sensitivity and fatty acid oxidation, and increases glucose uptake and utilization in target tissues. This lowers blood glucose levels. Metformin may exert antineoplastic effects through AMPK-mediated or AMPK-independent inhibition of mammalian target of rapamycin (mTOR), which is up-regulated in many cancer tissues. It also reduces cyclin D1. This inhibits cancer cell proliferation. Furthermore, this agent also inhibits tumor cell migration and invasion by inhibiting matrix metalloproteinase-9 (MMP-9) expression which is mediated through the suppression of transcription activator protein-1 (AP-1) activation. Also, metformin reduces hyperinsulinemia which may contribute to an anti-tumor effect. Metformin may increase the prostate-specific antigen (PSA) doubling time and may lower serum PSA levels. NCI Drug Dictionary

Treatments listed in the registry

• Metformin (Drug): Given PO

Na · Single Group · masking: None

Main goals

• Proportion of Participants who have completed at least (≥) 80% of planned metformin doses by 6 months (6 months)

Other goals

• Progression Free Survival (PFS)

Planned enrollment: 15 (estimated).

• Chao Family Comprehensive Cancer Center, University of California, Irvine, Orange, California

Site status as of Oct 30, 2026. Check the live record before contacting a site.

• ClinicalTrials.gov NCT07693452
• NCI Drug Dictionary: C29251

Registry record reviewed as fetched Oct 30, 2026, last updated by the sponsor Jul 12, 2026. Public record; not medical advice.