Xanomeline (LY-246,708) is an orthosteric muscarinic acetylcholine receptor (mAChR) agonist, often referred to as M1/M4-preferring. It is also known to act as a M5 receptor antagonist. Xanomeline was studied in clinical trials phase I in schizophrenia. In Phase II clinical trials in Alzheimer’s patients, xanomeline significantly improved several measures of cognitive function, yet produced unwanted side effects that limited patient compliance. The side effects seem to be associated with rapid metabolism of the alkyloxy side chain following oral administration, resulting in a nonselective, yet active compound with limited therapeutic utility. Despite a second Phase II clinical trial with a patch formulation, the liabilities of xanomeline still outweigh its benefits.

MGL-3196 is a first-in-class, orally administered, small-molecule, liver-directed, THR β-selective agonist. Preclinical, toxicology and Phase 1 clinical data suggest MGL-3196 has an attractive, differentiated profile as a potential treatment for non-alcoholic steatohepatitis (NASH) and dyslipidemias. THR-β selectivity also enhances the safety profile of MGL-3196, compared to non-selective agents. MGL-3196 has shown no suppression of the central thyroid axis, no THR-α effects on heart rate or bone, and no elevation of liver enzymes. These characteristics make MGL-3196 among the most promising molecules in development in this therapeutic area. MGL-3196 is in a Phase 2 clinical trial for the treatment of non-alcoholic steatohepatitis (NASH).

Elafibranor (GFT505) is an agonist of the peroxisome proliferator-activated receptor-α and peroxisome proliferator-activated receptor-δ. GFT505 has an active metabolite, GFT1007, and both have potent agonist activity for PPAR-a and to a lesser extent for PPAR-d. Elafibranor improves insulin sensitivity, glucose homeostasis, and lipid metabolism and reduces inflammation. Elafibranor (GFT505) reverses nonalcoholic steatohepatitis (NASH) to prevent fibrosis progression. With an outstanding safety and tolerance profile, elafibranor provides NASH patients with needed cardio-protective benefits. Elafibranor is currently being evaluated in the clinical Phase 3 study RESOLVE-IT. The safety profile of GFT505 from the completed clinical trials appears satisfactory with no indication of PPAR-g agonist effects such as edema or body weight gain.

MBX-8025 (Seladelpar) is an agonist of peroxisome proliferator-activated receptor delta. MBX-8025 improves insulin sensitivity and reverses dyslipidemia and hepatic storage of lipotoxic lipids to improve nonalcoholic steatohepatitis pathology in atherogenic diet-fed obese diabetic mice. MBX-8025 improves lipoprotein subfractions associated with atherogenic dyslipidemia. CymaBay Therapeutics is developing MBX-8025 for the treatment of patients with the autoimmune liver disease, primary biliary cholangitis and nonalcoholic steatohepatitis.

Palovarotene (R-667, RO-3300074) was developed by Roche Holding AG as a selective retinoic acid receptor gamma agonist for the treatment of emphysema. Phase I clinical trials of palovarotene in patients with emphysema demonstrated that the drug is well tolerated, with improvements observed in markers of emphysema progression. Unlike all-trans retinoic acid, the pharmacokinetic profile of palovarotene appears to be dose-proportional. However, those studies were discontinued. Palovarotene is also being investigated in phase II of the clinical trial in the treatment of Fibrodysplasia Ossificans Progressiva (FOP). Palovarotene received Fast Track designation from the U.S. Food and Drug Administration (FDA) and orphan designations for the treatment of FOP from both the FDA and the European Medicines Agency (EMA).

Tapinarof (also known as benvitimod, WB-1001; GSK-2894512), a therapeutic aryl hydrocarbon receptor agonist that selectively modulates the cytokine cascade deep under the skin, a process that rapidly decreases inflammations and skin plague. Tapinarof cream 1% (VTAMA®) is being developed by Dermavant Sciences Inc. (a subsidiary of Roivant Sciences Inc.) as a once-daily topical treatment for plaque psoriasis and atopic dermatitis. In May 2022, tapinarof cream 1% was approved in the USA for the topical treatment of plaque psoriasis in adults. Tapinarof cream 1% is also being investigated for the treatment of atopic dermatitis.

Difelikefalin (Korsuva™) is a synthetic peptide agonist of the kappa opioid receptor being developed by Cara Therapeutics for the treatment of pruritus. In August 2021, intravenous difelikefalin was approved in the USA for the treatment of moderate-to-severe pruritus associated with chronic kidney disease (CKD) in adults undergoing haemodialysis. Difelikefalin selectively acts on kappa opioid receptors in peripheral tissues, which contribute to pruritis and nociception. The activation of opioid receptors in peripheral neurons and keratinocytes reduces afferent (sensory) impulses towards the central nervous system, decreasing pain signals. Activating kappa opioid receptors on immune cells, including monocytes and T lymphocytes, decreases the release of pro-inflammatory chemicals such as prostaglandins.

Remimazolam is an intravenous benzodiazepine sedative-hypnotic with rapid onset and offset of action. This compound undergoes organ-independent metabolism to an inactive metabolite. Like other benzodiazepines, remimazolam can be reversed with flumazenil to rapidly terminate sedation and anesthesia. Phase I and II clinical trials have shown that remimazolam is safe and effective when used for procedural sedation. Phase III clinical trials have been completed investigating efficacy and safety in patients undergoing bronchoscopy and colonoscopy. The developer of this drug has suggested that intensive care unit sedation (beyond 24 hours) could be another possible indication for further development, since it is unlikely that prolonged infusions or higher doses of remimazolam would result in accumulation and extended effect.

Setmelanotide (IMCIVREE™) is a melanocortin-4 (MC4) receptor agonist developed by Rhythm Pharmaceuticals (Rhythm) for the treatment of ultrarare genetic disorders of obesity. Setmelanotide was approved on 27 November 2020 in the USA as a subcutaneous (SC) injectable formulation for chronic weight management in adult and pediatric patients 6 years of age and older with obesity due to proopiomelanocortin (POMC), proprotein convertase subtilisin/kexin type 1 (PCSK1), or leptin receptor (LEPR) deficiency confirmed by genetic testing demonstrating variants in POMC, PCSK1, or LEPR genes that are interpreted as pathogenic, likely pathogenic, or of uncertain significance (VUS). Rhythm are also developing the drug for the treatment of obesity associated with other rare genetic disorders including Bardet–Biedl Syndrome, Alström Syndrome, POMC and other MC4R pathway heterozygous defciency obesities, and POMC epigenetic disorders.

Vibegron is a selective beta 3 adrenergic receptor (β3AR) agonist that is being developed in Japan jointly by Kyorin Pharmaceutical Co., Ltd and Kissei Pharmaceutical Co., Ltd and in other regions worldwide (except in several other Asian countries) by Urovant Sciences for the treatment of overactive bladder (OAB). Vibegron potently activates human b3AR and increases cAMP levels, with an EC50 of 1.1 nM. Based on results from Japanese phase III trials, vibegron received approval in Japan in September 2018 for this indication. Vibegron, an active ingredient of Beova® Tablets, is a novel once-daily oral treatment for overactive bladder (OAB), acts selectively on the bladder's β3-adrenergic receptor, relaxes the bladder and enhances the urine collection, and consequently improves the symptoms of urgency, urinary frequency and urge urinary incontinence associated with OAB. On December 23, 2020 the FDA approved vibegron (Gemtesa) for the treatment of adult patients with overactive bladder (OAB) with symptoms of urge urinary incontinence (UUI), urgency, and urinary frequency.