PL8177
PL8177, oral MC1R agonist peptide
Palatin's oral melanocortin-1 receptor agonist peptide for ulcerative colitis, with a small Phase 2 showing 33% remission versus 0% on placebo before the study was cut short for licensing.
Overview
PL8177 is a cyclic peptide agonist of MC1R designed to act in the gut and resolve inflammation rather than suppress the immune system. The Phase 2 in ulcerative colitis stopped at 12 patients when Palatin sought a partner, reporting clinical remission in 33% versus 0% and clinical response in 78% versus 33%, with no adverse events. The numbers are encouraging but the study is far too small to be conclusive. Palatin's separate oral MC4R agonist PL7737 for obesity had Phase 1 data expected in 2026.
Mechanism of action
MC1R agonism on immune cells and gut epithelium promoting resolution of inflammation.
Key studies & citations
- Human2025
Palatin announces positive topline results from Phase 2 ulcerative colitis study of PL8177
Remission 33% versus 0% in 12 patients.
Palatin press release - Human2025
PL8177 Phase 2 in ulcerative colitis
Stopped early for out-licensing; underpowered.
ClinicalTrials.gov NCT05466890
Frequently asked questions
Is PL8177 related to PT-141?
Both come from Palatin and both are melanocortin agonists, but PT-141 targets MC4R for sexual function while PL8177 targets MC1R for gut inflammation.