Monlunabant (INV-202, MRI-1891, or S-MRI-1891) is a peripherally selective cannabinoid receptor 1 inverse agonist, discovered as a ò-arrestin-2-biased cannabinoid receptor 1 antagonist by Dr George Kunos, Dr Resat Cinar, and Dr Malliga Iyer at the National Institutes of Health. It was developed as a weight loss drug by Inversago Pharma.
Novo NordiskâÂÂs obesity drug monlunabant showed only modest weight loss in a Phase 2a trial. The drug was associated with higher rates of mild to moderate neuropsychiatric side effects like anxiety and sleep disturbances. Suicidal ideations were not reported.