The specificity of the immune response relies on processing of foreign proteins and presentation of antigenic peptides at the cell surface. Inhibition of antigen presentation, and the subsequent activation of T-cells, should, in theory, modulate the immune response. The cysteine protease Cathepsin S performs a fundamental step in antigen presentation and therefore represents an attractive target for inhibition. Herein, we report a series of potent and reversible Cathepsin S inhibitors based on dipeptide nitriles. These inhibitors show nanomolar inhibition of the target enzyme as well as cellular potency in a human B cell line. The first X-ray crystal structure of a reversible inhibitor cocrystallized with Cathepsin S is also reported.

A series of inhibitors of Pim-2 kinase identified by high-throughput screening is described. Details of the hit validation and lead generation process and structure-activity relationship (SAR) studies are presented. Disclosure of an unconventional binding mode for 1, as revealed by X-ray crystallography using the highly homologous Pim-1 protein, is also presented, and observed binding features are shown to correlate with the Pim-2 SAR. While highly selective within the kinase family, the series shows similar potency for both Pim-1 and Pim-2, which was expected on the basis of homology, but unusual in light of reports in the literature documenting a bias for Pim-1. A rationale for these observations based on Pim-1 and Pim-2 K(M(ATP)) values is suggested. Some interesting cross reactivity with casein kinase-2 was also identified, and structural features which may contribute to the association are discussed.

A greater understanding of pathological mechanisms for Pim kinases has stimulated the recent development of a variety of inhibitor classes with one compound advancing into the clinic earlier this year. Ongoing studies will help define applications for these inhibitors in the treatment of Pim-associated human diseases.

High-throughput screening is routinely employed as a method for the identification of novel hit structures. Large numbers of active compounds are typically procured in this way and must undergo a rigorous validation process. This process is described in detail for a collection of screening hits identified as inhibitors of IkappaB kinase-beta (IKKbeta), a key regulatory enzyme in the nuclear factor-kappaB (NF-kappaB) pathway. From these studies, a promising hit series was selected. Subsequent lead generation activities included the development of a pharmacophore hypothesis and structure-activity relationship (SAR) for the hit series. This led to the exploration of related scaffolds offering additional opportunities, and the various structural classes were comparatively evaluated for enzyme inhibition, selectivity, and drug-like properties. A novel lead series of thienopyridines was thereby established, and this series advanced into lead optimization for further development.

IntroductionThis study compared the efficacy and safety of similar U-100 insulin glargine products, namely, Lilly insulin glargine (LY IGlar; Basaglar®) and the reference insulin glargine product (IGlar; Lantus®), used once daily in combination with oral antihyperglycemic medications (OAMs) in adults with type 2 diabetes (T2D).MethodsELEMENT 5 was a phase III, randomized, multinational, open-label, treat-to-target, 24-week trial. Participants were insulin naïve (glycated hemoglobin [HbA1c] ≥ 7.0% to ≤ 11.0%) or on basal insulin (IGlar, neutral protamine Hagedorn or insulin detemir; HbA1c ≤ 11.0%) and taking ≥ 2 OAMs. The primary objective was to show  that LY IGlar is noninferior to IGlar in terms of HbA1c reduction (0.4% noninferiority margin).ResultsThe study population (N = 493) was predominantly Asian (48%) or White (46%), with similar baseline characteristics between arms (P > 0.05). At 24 weeks, LY IGlar was noninferior to IGlar in terms of change in HbA1c level from baseline (− 1.25 vs. − 1.22%, respectively; least squares mean difference − 0.04%; 95% confidence interval − 0.22%, 0.15%). Other 24-week efficacy and safety results were also similar between treatments (P > 0.05), including insulin dose; percentage of patients having HbA1c of < 7% and ≤ 6.5%; overall rate and incidence of total, nocturnal, and severe hypoglycemia; adverse events; insulin antibody response; and weight gain. Daily mean 7-point self-monitored blood glucose reduction was similar between treatments at 24 weeks, with no differences at any time point except premorning-meal (fasting) blood glucose (LY IGlar − 2.37 mmol/L; IGlar − 2.69 mmol/L; P = 0.007).ConclusionOverall, LY IGlar and IGlar combined with OAMs provided similar glucose control and safety findings in this T2D population, which included a greater proportion of Asian patients and had broader background basal insulin experience than a previously studied T2D population.Trial RegistrationClinicalTrials.gov identifier, NCT02302716.FundingEli Lilly and Company and Boehringer Ingelheim.Plain Language SummaryPlain language summary available for this article.Electronic supplementary materialThe online version of this article (10.1007/s13300-018-0549-3) contains supplementary material, which is available to authorized users.