Verubecestat (MK 8931) is a potentially first-in-class, potent β-site amyloid precursor protein cleaving enzyme 1 (BACE1) inhibitor being developed by Merck. Verubecestat (MK-8931) is a selective, structurally unique BACE1 inhibitor that reduced plasma, cerebrospinal fluid (CSF), and brain concentrations of Aβ40, Aβ42, and sAPPβ (a direct product of BACE1 enzymatic activity) after acute and chronic administration to rats and monkeys. Verubecestat was under investigation for the treatment of Alzheimer's disease, prodromal Alzheimer's disease, and amnestic mild cognitive impairment. In November 2013, Merck began the APECS trial in 1,500 participants with prodromal AD, aka mild cognitive impairment due to AD (aMCI). These patients have measurable cognitive deficits and a positive PET scan with the newly FDA-approved amyloid tracer flutemetamol, but are not functionally impaired. APECS compared 12 and 40 mg once-daily doses to placebo; treatment was to last for two years. APECS usef change from baseline on the Clinical Dementia Rating Sum of Boxes (CDR-SB), a continuous measure, as its primary outcome. Secondary outcomes evaluated a range of newer measures, including a cognitive composite, CSF tau, brain imaging of hippocampal volume and amyloid load, and others. This trial was being conducted in more than 90 locations worldwide; it completed enrollment in November 2016 and was expected to complete data collection for its primary outcome in 2019. In February 2018, APECS was discontinued and Merck no longer listed verubecestat in its research pipeline. APECS participants on 40 mg verubecestat scored worse than the placebo group on the CDR-SB and ADAS-Cog13 starting at 13 weeks. The effect was small and did not progress over time. The 12 mg treatment group also performed slightly worse than controls, with the difference reaching significance at scattered time points.

ISOMETHEPTENE, (R)- is an antimigraine drug candidate, which development was discontinued in 2016. It is a potent agonist of the imidazoline-1-receptor.

AZD-3759 is an oral inhibitor of both wild-type and mutant EGFR with IC50 values in nanomolar range. The drug was discovered by AstraZeneca for the treatment of non-small-cell lung cancer with CNS metastases. AZD-3759 can penetrate the blood-brain barrier and was confirmed to be effective in vitro with NSCLC cell lines as well as in mouse model of brain metastases. AZD-3759 is currently in Phase 1 clinical trial.

ETC-159 (ETC-1922159) is an inhibitor of membrane-bound O-acyltransferase porcupine. Porcupine palmitoleates Wnt and this modification is essential for binding to chaperone WLS and Frizzled receptors and is therefore required for the activity of all Wnts. ETC-159 exerts antineoplastic properties both in vitro and in vivo due to inhibition of Wnt pathway. ETC-159 development has progressed to phase I clinical trial.

BI 44370 was developed as a calcitonin gene-related peptide receptor antagonist for the treatment of acute migraine attacks. In spite of the positive results from the phase II clinical trials, the BI-44370 study has been discontinued.

Ajulemic acid, designated as Resunab™, is being developed by Corbus Pharmaceuticals, for the treatment of cystic fibrosis, systemic sclerosis, systemic lupus erythematosus.Ajulemic acid (AJA) is a first-in-class, synthetic, orally active, cannabinoid-derived drug that preferentially binds to the CB2 receptor and is nonpsychoactive. In preclinical studies, and in Phase 1 and 2 clinical trials, AJA showed a favorable safety, tolerability, and pharmacokinetic profile. It also demonstrated significant efficacy in preclinical models of inflammation and fibrosis. It suppresses tissue scarring and stimulates endogenous eicosanoids that resolve chronic inflammation and fibrosis without causing immunosuppression. AJA is currently being developed for use in 4 separate but related indications including systemic sclerosis (SSc), cystic fibrosis, dermatomyositis (DM), and systemic lupus erythematosus. Phase 2 clinical trials in the first 3 targets demonstrated that it is safe, is a potential treatment for these orphan diseases and appears to be a potent inflammation-resolving drug with a unique mechanism of action, distinct from the nonsteroidal anti-inflammatory drug (NSAID), and will be useful for treating a wide range of chronic inflammatory diseases.

Pranolium (UM-272) is propranolol derivative. It can reduce the extent of myocardial injury sustained during severe ischemia. UM-272 lacks significant beta-adrenergic blocking activity but retains the negative chronotropic, negative inotropic and antiarrhythmic effects common to both d- and l-propranolol. The protective effects of UM-272 during myocardial ischemia cannot be due to metabolic effects of the beta-adrenergic blockade but may be due to effects on oxygen consumption or to effects on myocardial membrane properties that are related to its antiarrhythmic and myocardial depressant activity. The ability of UM-272 to enhance blood flow to subendocardial myocardium may also play a role in its beneficial effects during ischemia. UM-272 may protect the ischemic heart through direct effects on myocardial Ca++ regulating mechanisms. UM-272 has kinetically similar use-dependent inhibitory action of the fast sodium channels of cardiac muscles as other Class Ia antiarrhythmic drugs like quinidine or procainamide. Pranolium was investigated as an antiarrhythmic agent.