Optimization of allosteric MEK inhibitors. Part 1: Venturing into underexplored SAR territories.

Using PD325901 as a starting point for identifying novel allosteric MEK inhibitors with high cell potency and long-lasting target inhibition in vivo, truncation of its hydroxamic ester headgroup was combined with incorporation of alkyl and aryl ethers at the neighboring ring position. Whereas alkoxy side chains did not yield sufficient levels of cell potency, specifically substituted aryloxy groups allowed for high enzymatic and cellular potencies. Sulfamide 28 was identified as a highly potent MEK inhibitor with nanomolar cell potency against B-RAF (V600E) as well as Ras-mutated cell lines, high metabolic stability and resulting long half-lives. It was efficacious against B-RAF as well as K-Ras driven xenograft models and showed-despite being orally bioavailable and not a P-glycoprotein substrate-much lower brain/plasma exposure ratios than PD325901.

Efficacy of once-daily, single-inhaler, fixed-dose combination of mometasone/indacaterol/glycopyrronium in patients with asthma with or without persistent airflow limitation: Post hoc analysis from the IRIDIUM study.

BACKGROUND: A novel, once-daily, fixed-dose combination of mometasone furoate/indacaterol acetate/glycopyrronium bromide (MF/IND/GLY) delivered via Breezhaler® is the first inhaled corticosteroid/long-acting ꞵ2-agonist/long-acting muscarinic antagonist (ICS/LABA/LAMA) therapy approved for the maintenance treatment of asthma in adults inadequately controlled on ICS/LABA combination. In patients with asthma and persistent airflow limitation (PAL), maximal treatment, especially with combination is suggested. This post hoc analysis of data from the IRIDIUM study assessed the efficacy of MF/IND/GLY in asthma patients with and without PAL. METHODS: Patients with post-bronchodilator FEV1 ≤80% of predicted and FEV1/FVC ratio of ≤0.7 were categorised as PAL subgroup and the remaining as the non-PAL subgroup. Lung function parameters (FEV1, PEF, and FEF25%-75%) and annualised asthma exacerbations rates were evaluated in both subgroups across the treatment arms: once-daily high-dose MF/IND/GLY (160/150/50 µg), high-dose MF/IND (320/150 µg) and twice-daily high-dose fluticasone/salmeterol (FLU/SAL; 500/50 µg). RESULTS: Of the 3092 randomised patients, 64% (n = 1981) met the criteria for PAL. Overall, there was no evidence of treatment difference between PAL and non-PAL subgroups (interaction P-value for FEV1, FEF25%-75%, PEF, moderate or severe exacerbations, severe exacerbations and all exacerbations were 0.42, 0.08, 0.43 0.29, 0.35 and 0.12, respectively). In the PAL subgroup, high-dose MF/IND/GLY versus high-dose MF/IND and high-dose FLU/SAL improved trough FEV1 (mean difference: 102 mL [P < 0.0001] and 137 mL [P < 0.0001]) and reduced moderate or severe (16% and 32%), severe (25% and 39%) and all exacerbations (19% and 38%), respectively. CONCLUSIONS: Once-daily fixed-dose MF/IND/GLY was efficacious in asthma patients with and without persistent airflow limitation.

A Review of the Unique Drug Development Strategy of Indacaterol Acetate/Glycopyrronium Bromide/Mometasone Furoate: A First-in-Class, Once-Daily, Single-Inhaler, Fixed-Dose Combination Treatment for Asthma.

A novel, once-daily (o.d.), fixed-dose combination (FDC) of indacaterol acetate (IND), glycopyrronium bromide (GLY), and mometasone furoate (MF), delivered by the inhaler Breezhaler® device, is the first long-acting beta2-adrenergic agonist/long-acting muscarinic antagonist/inhaled corticosteroid (LABA/LAMA/ICS) therapy to be approved for maintenance treatment of asthma in adults inadequately controlled on LABA/ICS. The approval of IND/GLY/MF in the European Union (EU) also included an optional electronic sensor and smartphone (or other suitable device) application, making it the first "digital companion" that can be prescribed with an asthma medication. As a result, the European Medicines Agency included this approval as one of the "outstanding contributions to public health" (for Pneumology/Allergology) in their 2020 highlights report. Alongside IND/GLY/MF, an o.d. LABA/ICS FDC, IND/MF, was also developed and approved. This review outlines the unique strategy used in the accelerated development of IND/GLY/MF that combined various approaches: (1) selecting individual components with established efficacy/safety, (2) bridging doses to optimize efficacy/safety of IND/GLY/MF and IND/MF delivered via the Breezhaler® device, (3) developing IND/GLY/MF and IND/MF in parallel, and (4) submission for regulatory approval before formal completion of the pivotal phase III studies. IND/GLY/MF and IND/MF were combined in a single-development plan (PLATINUM program), which comprised four phase III studies: QUARTZ and PALLADIUM evaluated IND/MF while IRIDIUM and ARGON evaluated IND/GLY/MF. A unique feature was the inclusion of two LABA/ICS comparators in the pivotal IRIDIUM study-IND/MF as an internal comparator, and high-dose salmeterol xinafoate/fluticasone propionate (SAL/FLU) as a marketed comparator. In the ARGON study, IND/GLY/MF was compared against o.d. tiotropium (via Respimat®) plus twice-daily (b.i.d.) high-dose SAL/FLU (via Diskus®). As a result of this development strategy, the development and approval of IND/GLY/MF was accelerated by ca. 4 years as against what would be expected from a traditional approach, novel data were generated, and a unique optional digital companion was approved in the EU. A Video Abstract by Dr Dominic Brittain, Global Drug Development, Novartis. (MP4 228293 kb).

Cardiovascular safety of mometasone/indacaterol and mometasone/indacaterol/glycopyrronium once-daily fixed-dose combinations in asthma: pooled analysis of phase 3 trials.

OBJECTIVE: To evaluate cardiovascular safety of two new inhaled fixed-dose combinations for treatment of asthma: (i) the inhaled corticosteroid/long-acting beta2-agonist (ICS/LABA) mometasone furoate/indacaterol acetate (MF/IND), (ii) the ICS/LABA/long-acting muscarinic antagonist (LAMA) MF/IND/glycopyrronium bromide (GLY). METHODS: Patient-level data were pooled from four randomized trials, including 52-week studies PALLADIUM (n = 2216) and IRIDIUM (n = 3092), 24-week study ARGON (n = 1426), and 12-week study QUARTZ (n = 802). Cardio-/cerebrovascular (CCV) event frequencies were examined in the following comparisons: (1) LABA effect: pooled-dose MF/IND vs. pooled-dose MF; (2) LAMA effect: pooled-dose MF/IND/GLY vs. pooled-dose MF/IND; (3) ICS-dose effects: (a) high-dose MF/IND vs. medium-dose MF/IND, (b) high-dose MF/IND/GLY vs. medium-dose MF/IND/GLY; (4) intra-class effects: (a) high-dose MF/IND vs. Fluticasone/Salmeterol (F/S), (b) high-dose MF/IND/GLY vs. F/S + Tiotropium (TIO). Risk estimates (percentage of patients with ≥1 CCV event) and risk differences (RDs) with 95% confidence intervals (CIs) were calculated for each comparison. RESULTS: The frequency of CCV events was low, without notable differences between comparison groups. Risk estimates and corresponding RDs (95% CIs) were as follows: (1) pooled-dose MF/IND = 2.35%, pooled-dose MF = 2.18%, RD = 0.17% (-1.00%, 1.34%); (2) pooled-dose MF/IND/GLY = 3.65%, pooled-dose MF/IND = 3.77%, RD = -0.12% (-1.63%, 1.39%); (3a) high-dose MF/IND = 3.69%, medium-dose MF/IND = 3.35%, RD = 0.34% (-1.25%, 1.94%); (3b) high-dose MF/IND/GLY = 2.84%, medium-dose MF/IND/GLY = 2.02%, RD = 0.82% (-0.49%, 2.13%); (4a) high-dose MF/IND = 3.69%, F/S = 2.82%, RD = 0.87% (-0.66%, 2.40%); (4b) high-dose MF/IND/GLY = 1.26%, F/S + TIO = 1.05%, RD = 0.21% (-1.26%, 1.68%). CONCLUSIONS: There was no evidence of increased cardiovascular risk attributable to the addition of IND to MF or addition of GLY to MF/IND. Similarly, no evidence of increased cardiovascular risk was observed with an increase in the ICS-dose or relative to F/S ± TIO.

G protein-coupled receptor 30 localizes to the endoplasmic reticulum and is not activated by estradiol.

The classical estrogen receptor (ER) mediates genomic as well as rapid nongenomic estradiol responses. In case of genomic responses, the ER acts as a ligand-dependent transcription factor that regulates gene expression in estrogen target tissues. In contrast, nongenomic effects are initiated at the plasma membrane and lead to rapid activation of cytoplasmic signal transduction pathways. Recently, an orphan G protein-coupled receptor, GPR30, has been claimed to bind to and to signal in response to estradiol. GPR30 therefore might mediate some of the nongenomic estradiol effects. The present study was performed to clarify the controversy about the subcellular localization of GPR30 and to gain insight into the in vivo function of this receptor. In transiently transfected cells as well as cells endogenously expressing GPR30, we confirmed that the receptor localized to the endoplasmic reticulum. However, using radioactive estradiol, we observed only saturable, specific binding to the classical ER but not to GPR30. Estradiol stimulation of cells expressing GPR30 had no impact on intracellular cAMP or calcium levels. To elucidate the physiological role of GPR30, we performed in vivo experiments with estradiol and G1, a compound that has been claimed to act as selective GPR30 agonist. In two classical estrogen target organs, the uterus and the mammary gland, G1 did not show any estrogenic effect. Taken together, we draw the conclusion that GPR30 is still an orphan receptor.

Synthesis of 7a-substituted Hajos-Wiechert ketone analogues.

A general and efficient route to 2-substituted 1,3-cyclopentadiones 3 has been developed. This operationally simple, two-step procedure is amenable to multigram scale preparations of these useful synthetic intermediates. These compounds are then transformed to previously unknown, higher analogues of the Hajos-Parrish-Eder-Sauer-Wiechert ketone (enone 1, R = Me) following an enantioselective Robinson annulation.

From solution-phase to solid-phase enyne metathesis: crossover in the relative performance of two commonly used ruthenium pre-catalysts.

A crossover in the ability of two distinct ruthenium-based metathesis pre-catalysts to effect the synthesis of dialkenylboronic esters in solution and on the solid-phase was observed. Specifically, while the Grubbs 2nd generation pre-catalyst 3 affords a greater degree of conversion to product than the Hoveyda-Grubbs pre-catalyst 2 in a solution-phase enyne-metathesis reaction, this trend is reversed in the solid-phase variant. Systematic investigation showed this trend to be general, regardless of variations in the homoallylic alcohol and alkynylboronic ester components of the reaction, as well as in the type of solid support employed. Experiments to determine a mechanistic hypothesis for this trend highlighted the significance of the ruthenium remaining bound to the substrate after metathetic rearrangement and found the presence of phosphine ligand to be detrimental to the success of the solid-phase reaction. Therefore, these results suggest an expanded role for phosphine-free pre-catalysts, such as 2, in challenging solid-phase metathesis reactions.