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.

Fruquintinib is a highly selective small molecule drug candidate that has been shown to inhibit VEGFR 24 hours a day via an oral dose, with lower off-target toxicities compared to other targeted therapies. Mechanistically, Fruquintinib selectively blocks VEGF-mediated receptor autophosphorylation, thus inhibiting endothelial cell proliferation and migration. In preclinical in vitro studies using a 32P-ATP assay, Fruquintinib selectively inhibited the tyrosine kinase activity associated with VEGFR-1, VEGFR-2, and VEGFR-3 at concentrations in the nanomolar range, but showed little inhibition against a panel of 254 kinases related to cell cycle or cell proliferation, including cyclin-dependent kinase (CDK1, 2, 5), the epidermal growth factor receptor (EGFR), the mesenchymal-epithelial transition factor (c-Met), and platelet-derived growth factor receptor β (PDGFRβ) kinase. In cellular assays, Fruquintinib potently inhibited VEGF-stimulated VEGFR phosphorylation and proliferation in human umbilical vein endothelial cells. Fruquintinib demonstrated potent antiangiogenic effect and anti-tumor activity in xenograft models of colon adenocarcinoma (HT-29), non-small cell lung cancer (NSCLC; NCI-H460), renal clear cell carcinoma (Caki-1), and gastric carcinoma (BGC823) in mice treated for 3 weeks. Fruquintinib is currently under joint development in China by Chi-Med and its partner Eli Lilly and Company (“Lilly”). Chi-Med and Lilly jointly announced top-line results from the FRESCO CRC trial on March 3, 2017. In addition, Fruquintinib is being studied in China in Phase III pivotal trial in non-small cell lung cancer (“NSCLC”), known as FALUCA; and a Phase II study using Fruquintinib combined with Iressa® (gefitinib) in the first-line setting for patients with advanced or metastatic NSCLC.

Leniolisib (JOENJA®) is an oral selective phosphoinositide 3-kinase-delta (PI3Kdelta) inhibitor being developed by Pharming Group NV in-licensed from Novartis for the treatment of immunodeficiency disorders. Leniolisib inhibits PI3K-delta by blocking the active binding site of PI3K-delta. In cell-free isolated enzyme assays, leniolisib was selective for PI3K-delta over PI3K-alpha (28-fold), PI3K-beta (43-fold), and PI3K-gamma (257-fold), as well as the broader kinome. In cell-based assays, leniolisib reduced pAKT pathway activity and inhibited proliferation and activation of B and T cell subsets. Gain-of-function variants in the gene encoding the p110-delta catalytic subunit or loss of function variants in the gene encoding the p85-alpha regulatory subunit each cause hyperactivity of PI3K-delta. Leniolisib inhibits the signalling pathways that lead to increased production of PIP3, hyperactivity of the downstream mTOR/AKT pathway, and to the dysregulation of B and T cells. In March 2023, leniolisib received its first approval for the treatment of activated PI3Kdelta syndrome (APDS) in adult and paediatric patients 12 years of age and older. Leniolisib is also under regulatory review in European Union for the treatment of APDS. Development of leniolisib for the treatment of Sjögren's syndrome has been discontinued.

Oteseconazole (VIVJOA™) is an orally administered azole antifungal agent developed by Mycovia Pharmaceuticals for the treatment of fungal infections. It inhibits cytochrome P450 (CYP) 51, thereby affecting the formation and integrity of the fungal cell membrane, but has a low affinity for human CYP enzymes due to its tetrazole metal-binding group. Oteseconazole is the first agent to be approved (in April 2022) for recurrent vulvovaginal candidiasis (RVVC) in the USA, where it is indicated to reduce the incidence of RVVC in females with a history of RVVC who are NOT of reproductive potential. Clinical development for the treatment of onychomycosis, and invasive and opportunistic infections is ongoing.

Amisulpride, a benzamide derivative, shows a unique therapeutic profile being atypical antipsychotic. At low doses, it enhances dopaminergic neurotransmission by preferentially blocking presynaptic dopamine D2/D3 autoreceptors. At higher doses, amisupride antagonises postsynaptic dopamine D2 and D3 receptors, preferentially in the limbic system rather than the striatum, thereby reducing dopaminergic transmission. In addition its antagonism at serotonin 5-HT7 receptors likely underlies the antidepressant actions. Amisulpride is approved for clinical use in treating schizophrenia in a number of European countries and also for treating dysthymia, a mild form of depression, in Italy.

Fostemsavir (BMS-663068) is an investigational attachment inhibitor with a unique mechanism of action. It is a prodrug of temsavir, which binds to HIV envelope glycoprotein 120 (gp120), thereby preventing viral attachment to the host CD4 cell surface receptor. In the absence of effective binding of HIV gp120 with the host CD4 receptor, HIV does not enter the host cell. Because fostemsavir has a novel mechanism of action, the drug should have full activity against HIV strains that have developed resistance to other classes of antiretroviral medications. In a phase 2b study of treatment-experienced individuals, fostemsavir appeared to be well tolerated. Phase 3 studies are ongoing.

Selumetinib (AZD6244 or ARRY-142886) is a potent, selective, and ATP-uncompetitive inhibitor of Ras-Raf-mitogen-activated protein kinase kinase (MEK1/2). This inhibition can prevent ERK activation, disrupt downstream signal transduction, and inhibit cancer cell proliferation and survival. Selumetinib has shown tumour suppressive activity in multiple rodent models of human cancer including melanoma, pancreatic, colon, lung, and breast cancers. AstraZeneca is responsible for development and commercialization of selumetinib.

Tenapanor is an inhibitor of the sodium-proton (Na(+)/H(+)) exchanger NHE3 and reduces sodium absorption in the GI tract, thus increasing intestinal fluid. Ardelyx has completed Phase 3 development of tenapanor for the treatment of irritable bowel syndrome with constipation (IBS-C) and submitted a new drug application to the U.S. Food and Drug Administration for the treatment of patients with IBS-C. In addition, tenapanor successfully completed phase III clinical trial for the treatment of hyperphosphatemia in people with end-stage renal disease who are on dialysis and RDX013, a potassium secretagogue program for the potential treatment of high potassium, or hyperkalemia, a problem among certain patients with kidney and/or heart disease.

Cenobamate (also known as YKP3089) is a small molecule sodium channel blocker in development for the treatment of partial-onset seizures in adult patients. In mice and rats, Cenobamate displayed an anticonvulsant activity in the maximal electroshock test and prevented seizures induced by chemical convulsants such as pentylenetetrazol and picrotoxin. In addition, Cenobamate was reported to be effective in two models of focal seizure, the hippocampal kindled rat and the mouse 6 Hz psychomotor seizure models. Two completed adequate and well-controlled clinical studies demonstrated a significant reduction in focal seizures with Cenobamate in patients with epilepsy, and a long-term open-label phase 3 safety clinical trial is currently ongoing. Cenobamate is considered a new generation antiepileptic therapy and clinical trials have shown that it may be more effective and safer than existing drugs. If licensed, Cenobamate will offer a new adjunctive treatment option for patients with partial focal epilepsy.

LASMIDITAN is a serotonin (5-HT) receptor agonist without vasoconstrictor activity, which selectively binds to the 5-HT(1F) receptor subtype. It is under development for the treatment of migraine.