MK-1903 is a potent and selective hydroxycarboxylic acid receptor 2 (HCA2, GPR109A) full agonist. Exhibits no binding at the GRP109B receptor. This drug had been in phase II clinical trial for the treatment of atherosclerosis and Dyslipidemia. But then, according to Merck, elevation of HDL cholesterol relative to placebo did not meet the trial's pre-specified primary objective for efficacy; no safety signals were implicated as drivers of the decision to discontinue development.

URB-597 (KDS-4103) is a highly potent and selective inhibitor of the enzyme fatty acid amide hydrolase (FAAH), which catalyzes the intracellular hydrolysis of the endocannabinoid anandamide. URB597 is one the best studied carbamate-based inhibitors. Early studies showed that the compound did not inhibit or bind related biological targets. Administration of URB597 to rats and subsequent in vivo evaluation of brain FAAH activity showed the compound elevated endogenous anandamide levels. Importantly, the compound did not produce catalepsy, hypothermia, or hyperphagia, three of the typical effects of exogenous cannabinoids. The compound did produce antinociceptive effects in the mouse hot-plate test, which were reversed by the CB1 antagonist rimonabant. These findings again support the expectation that inhibition of FAAH produces pharmacology distinct from an exogenous CB1 agonist. A more detailed study was published later showing time-course data in mice demonstrating elevation of anandamide, oleamide, and N-palmitoyl ethanolamine for 2–6 h after administration of URB597. In vivo administration of URB597 showed almost complete inhibition of FAAH by the compound, and the FAAH inhibition was still approximately 70% after 16 h. Complete recovery of CNS FAAH activity was observed 24 h after administration of URB597. In vivo administration of URB597 or the cannabinoid receptor agonist HU210 reduced both mechanical allodynia and thermal hyperalgesia in the CFA model of inflammatory pain. Effects in the inflammatory model were partially reversed by CB1 and CB2 antagonists. In a related study, the compound produced analgesic effects in the mouse CCI model (neuropathic) when administered orally. These effects were also reversed by both CB1 and CB2 antagonists.

Nacubactam (FPI-1459) was developed as an antibacterial drug. Nacubactam successfully has completed phase I clinical trials for the treatment of serious gram-negative bacterial infections. The drug is currently being developed for the treatment of complicated urinary tract infection, hospital-acquired bacterial pneumonia, ventilator-associated bacterial pneumonia, and complicated intra-abdominal infections. FPI-1459 works through several mechanisms of action, inhibiting a number of beta-lactamase enzymes as well as certain bacterial cell wall enzymes. In January 2019, FPI-1459 received Fast Track and Qualified Infectious Disease Product designations from the U.S. Food and Drug Administration (FDA).

(S,R)-3-Phenyl-4,5-dihydro-5-isoxasole acetic acid (VGX-1027, GIT-027) is an isoxazole compound that exhibits various immunomodulatory properties. This compound reduced the secretion of IL-1beta, TNF-alpha and IL-10 from purified murine macrophages stimulated "in vitro" with lipopolysaccharide (LPS), and it also modified the signaling pathways induced in these cells by LPS entailing reduced activation of NF-kappaB and p38 MAP kinase pathways along with up-regulation of ERK pathways. The animals receiving VGX-1027 exhibited reduced production of the proinflammatory mediators tumor necrosis factor-alpha, IL-1beta, macrophage migration inhibitory factor, and inducible nitric-oxide synthase-mediated nitric oxide generation in both pancreatic islets and peripheral compartments. Inovio Pharmaceuticals is developing VGX-1027 for the treatment of inflammatory conditions such as rheumatoid arthritis, type 1 diabetes mellitus, uveitis and ulcerative colitis.

PL-3994 is a novel natriuretic cyclic peptide. It is a receptor-A (NPR-A) and receptor-C (NPR-C) agonist. PL-3994 has high affinity for recombinant human, dog, or rat NPR-As. PL-3994 produced concentration-dependent relaxation of pre-contracted guinea-pig trachea. PL-3994 elicited a potent, concentration-dependent but small relaxation of pre-contracted human precision-cut lung slices. Intratracheal PL-3994 produced a dose-dependent inhibition of the bronchoconstrictor response evoked by aerosolized methacholine, but was without significant effect on cardiovascular parameters. PL-3994 was resistant to degradation by human neutral endopeptidase. PL-3994 was well tolerated in subjects with controlled hypertension. A phase I and phase II trial have been successfully completed with PL-3994 with no safety concerns identified. In phase II study in subjects with hypertension who were receiving >1 antihypertensive medications, a significant reduction in blood pressure compared with placebo was observed. It appears that PL-3994 works synergistically with ACE inhibitors.