An isothermal calorimetry assay for determining steady state kinetic and enzyme inhibition parameters for SARS-CoV-2 3CL-protease.

This manuscript describes the application of Isothermal Titration Calorimetry (ITC) to characterize the kinetics of 3CL pro from the Severe Acute Respiratory Syndrome CoronaVirus-2 (SARS-CoV-2) and its inhibition by Ensitrelvir, a known non-covalent inhibitor. 3CL pro is the main protease that plays a crucial role of producing the whole array of proteins necessary for the viral infection that caused the spread of COVID-19, responsible for millions of deaths worldwide as well as global economic and healthcare crises in recent years. The proposed calorimetric method proved to have several advantages over the two types of enzymatic assays so far applied to this system, namely Förster Resonance Energy Transfer (FRET) and Liquid Chromatography-Mass Spectrometry (LC-MS). The developed ITC-based assay provided a rapid response to 3CL pro activity, which was used to directly derive the kinetic enzymatic constants K M and k cat reliably and reproducibly, as well as their temperature dependence, from which the activation energy of the reaction was obtained for the first time. The assay further revealed the existence of two modes of inhibition of 3CL pro by Ensitrelvir, namely a competitive mode as previously inferred by crystallography as well as an unprecedented uncompetitive mode, further yielding the respective inhibition constants with high precision. The calorimetric method described in this paper is thus proposed to be generally and widely used in the discovery and development of drugs targeting 3CL pro .

The efficacy of the analgesic GlyT2 inhibitor, ORG25543, is determined by two connected allosteric sites.

Glycine Transporter 2 (GlyT2) inhibitors have shown considerable potential as analgesics for the treatment of neuropathic pain but also display considerable side effects. One potential source of side effects is irreversible inhibition. In this study, we have characterized the mechanism of ORG25543 inhibition of GlyT2 by first considering three potential ligand binding sites on GlyT2-the substrate site, the vestibule allosteric site and the lipid allosteric site. The three sites were tested using a combination of molecular dynamics simulations and analysis of the inhibition of glycine transport of a series point mutated GlyT2 using electrophysiological methods. We demonstrate that the lipid allosteric site on GlyT2 is the most likely binding site for ORG25543. We also demonstrate that cholesterol derived from the cell membrane can form specific interactions with inhibitor-bound transporters to form an allosteric network of regulatory sites. These observations will guide the future design of GlyT2 inhibitors with the objective of minimising on-target side effects and improving the therapeutic window for the treatment of patients suffering from neuropathic pain.

Novel Phenylene Lipids That Are Positive Allosteric Modulators of Glycine Receptors and Inhibitors of Glycine Transporter 2.

Chronic pain is a complex condition that remains resistant to current therapeutics. We previously synthesized a series of N-acyl amino acids (NAAAs) that inhibit the glycine transporter, GlyT2, some of which are also positive allosteric modulators of glycine receptors (GlyRs). In this study, we have synthesized a library of NAAAs that contain a phenylene ring within the acyl tail with the objective of improving efficacy at both GlyT2 and GlyRs and also identifying compounds that are efficacious as dual-acting modulators to enhance glycine neurotransmission. The most efficacious positive allosteric modulator of GlyRs was 2-[8-(2-octylphenyl)octanoylamino]acetic acid (8-8 OPGly) which potentiates the EC5 for glycine activation of GlyRα1 by 1500% with an EC50 of 664 nM. Phenylene-containing NAAAs with a lysine headgroup were the most potent inhibitors of GlyT2 with (2S)-6-amino-2-[8-(3-octylphenyl)octanoylamino]hexanoic acid (8-8 MPLys) inhibiting GlyT2 with an IC50 of 32 nM. The optimal modulator across both proteins was (2S)-6-amino-2-[8-(2-octylphenyl)octanoylamino]hexanoic acid (8-8 OPLys), which inhibits GlyT2 with an IC50 of 192 nM and potentiates GlyRs by up to 335% at 1 µM. When tested in a dual GlyT2/GlyRα1 expression system, 8-8 OPLys caused the greatest reductions in the EC50 for glycine. This suggests that the synergistic effects of a dual-acting modulator cause greater enhancements in glycinergic activity compared to single-target modulators and may provide an alternate approach to the development of new non-opioid analgesics for the treatment of chronic pain.

Structural similarities between SARS-CoV2 3CLpro and other viral proteases suggest potential lead molecules for developing broad spectrum antivirals.

Considering the significant impact of the recent COVID-19 outbreak, development of broad-spectrum antivirals is a high priority goal to prevent future global pandemics. Antiviral development processes generally emphasize targeting a specific protein from a particular virus. However, some antiviral agents developed for specific viral protein targets may exhibit broad spectrum antiviral activity, or at least provide useful lead molecules for broad spectrum drug development. There is significant potential for repurposing a wide range of existing viral protease inhibitors to inhibit the SARS-CoV2 3C-like protease (3CLpro). If effective even as relatively weak inhibitors of 3CLpro, these molecules can provide a diverse and novel set of scaffolds for new drug discovery campaigns. In this study, we compared the sequence- and structure-based similarity of SARS-CoV2 3CLpro with proteases from other viruses, and identified 22 proteases with similar active-site structures. This structural similarity, characterized by secondary-structure topology diagrams, is evolutionarily divergent within taxonomically related viruses, but appears to result from evolutionary convergence of protease enzymes between virus families. Inhibitors of these proteases that are structurally similar to the SARS-CoV2 3CLpro protease were identified and assessed as potential inhibitors of SARS-CoV2 3CLpro protease by virtual docking. Several of these molecules have docking scores that are significantly better than known SARS-CoV2 3CLpro inhibitors, suggesting that these molecules are also potential inhibitors of the SARS-CoV2 3CLpro protease. Some have been previously reported to inhibit SARS-CoV2 3CLpro. The results also suggest that established inhibitors of SARS-CoV2 3CLpro may be considered as potential inhibitors of other viral 3C-like proteases.

The novel visual cycle inhibitor (±)-RPE65-61 protects retinal photoreceptors from light-induced degeneration.

The visual cycle refers to a series of biochemical reactions of retinoids in ocular tissues and supports the vision in vertebrates. The visual cycle regenerates visual pigments chromophore, 11-cis-retinal, and eliminates its toxic byproducts from the retina, supporting visual function and retinal neuron survival. Unfortunately, during the visual cycle, when 11-cis-retinal is being regenerated in the retina, toxic byproducts, such as all-trans-retinal and bis-retinoid is N-retinylidene-N-retinylethanolamine (A2E), are produced, which are proposed to contribute to the pathogenesis of the dry form of age-related macular degeneration (AMD). The primary biochemical defect in Stargardt disease (STGD1) is the accelerated synthesis of cytotoxic lipofuscin bisretinoids, such as A2E, in the retinal pigment epithelium (RPE) due to mutations in the ABCA4 gene. To prevent all-trans-retinal-and bisretinoid-mediated retinal degeneration, slowing down the retinoid flow by modulating the visual cycle with a small molecule has been proposed as a therapeutic strategy. The present study describes RPE65-61, a novel, non-retinoid compound, as an inhibitor of RPE65 (a key enzyme in the visual cycle), intended to modulate the excessive activity of the visual cycle to protect the retina from harm degenerative diseases. Our data demonstrated that (±)-RPE65-61 selectively inhibited retinoid isomerase activity of RPE65, with an IC50 of 80 nM. Furthermore, (±)-RPE65-61 inhibited RPE65 via an uncompetitive mechanism. Systemic administration of (±)-RPE65-61 in mice resulted in slower chromophore regeneration after light bleach, confirming in vivo target engagement and visual cycle modulation. Concomitant protection of the mouse retina from high-intensity light damage was also observed. Furthermore, RPE65-61 down-regulated the cyclic GMP-AMP synthase stimulator of interferon genes (cGAS-STING) pathway, decreased the inflammatory factor, and attenuated retinal apoptosis caused by light-induced retinal damage (LIRD), which led to the preservation of the retinal function. Taken together, (±)-RPE65-61 is a potent visual cycle modulator that may provide a neuroprotective therapeutic benefit for patients with STGD and AMD.

Psychometric Validation of the Psoriasis Symptoms and Impacts Measure (P-SIM): A Novel Patient-Reported Outcome Instrument for Patients with Plaque Psoriasis, Using Reported Data from the BE RADIANT Phase 3b Trial.

INTRODUCTION: This analysis assessed the psychometric properties of the Psoriasis Symptoms and Impacts Measure (P-SIM), a novel patient-reported outcome (PRO) tool designed to capture patient experiences of the signs, symptoms and impacts of psoriasis. METHODS: Blinded data from the BE RADIANT phase 3b trial of bimekizumab were analysed. In BE RADIANT, patients were randomised 1:1 to bimekizumab 320 mg every 4 weeks (Q4W) or secukinumab 300 mg (weekly until Week 4, then Q4W). Three items (itching, skin pain and scaling) of the P-SIM were electronically assessed throughout the trial and were scored from 0 to 10 (none to very severe signs/symptoms/impacts). Test-retest reliability was determined using intraclass correlations. Convergent validity was assessed between P-SIM and other relevant PRO and clinician-reported outcome (ClinRO) scores. Known-groups validity was assessed by comparing mean P-SIM item scores between patient subgroups based on the Psoriasis Area and Severity Index (PASI)/Investigator's Global Assessment (IGA) scores. Responsiveness was assessed via correlations between changes from baseline in P-SIM item scores and other relevant PRO and ClinRO scores. Anchor-based responder analyses and empirical cumulative distribution function (eCDF) curves determined responder thresholds. RESULTS: The three P-SIM items yielded high intraclass coefficients (> 0.70). By Week 48, the three P-SIM items had moderate (> 0.30 and ≤ 0.50) to strong (> 0.50) correlations with other PROs and weaker correlations with ClinROs, demonstrating good convergent validity. For almost all known-group comparisons, statistically significant between-subgroup score differences were seen across all three P-SIM items. Changes from baseline in the P-SIM and other relevant outcomes were above the acceptable threshold of ≤ 0.30, demonstrating sensitivity to change. Anchor-based analyses determined a ≥ four-point reduction from baseline to indicate marked clinically meaningful improvement for the P-SIM. CONCLUSION: These results support the validity, reliability and sensitivity to change of the P-SIM in assessing key symptoms (itching, skin pain and scaling) in patients with moderate to severe plaque psoriasis. TRIAL REGISTRATION: NCT03536884.

Inhibition of Glycine Re-Uptake: A Potential Approach for Treating Pain by Augmenting Glycine-Mediated Spinal Neurotransmission and Blunting Central Nociceptive Signaling.

Among the myriad of cellular and molecular processes identified as contributing to pathological pain, disinhibition of spinal cord nociceptive signaling to higher cortical centers plays a critical role. Importantly, evidence suggests that impaired glycinergic neurotransmission develops in the dorsal horn of the spinal cord in inflammatory and neuropathic pain models and is a key maladaptive mechanism causing mechanical hyperalgesia and allodynia. Thus, it has been hypothesized that pharmacological agents capable of augmenting glycinergic tone within the dorsal horn may be able to blunt or block aberrant nociceptor signaling to the brain and serve as a novel class of analgesics for various pathological pain states. Indeed, drugs that enhance dysfunctional glycinergic transmission, and in particular inhibitors of the glycine transporters (GlyT1 and GlyT2), are generating widespread interest as a potential class of novel analgesics. The GlyTs are Na+/Cl--dependent transporters of the solute carrier 6 (SLC6) family and it has been proposed that the inhibition of them presents a possible mechanism by which to increase spinal extracellular glycine concentrations and enhance GlyR-mediated inhibitory neurotransmission in the dorsal horn. Various inhibitors of both GlyT1 and GlyT2 have demonstrated broad analgesic efficacy in several preclinical models of acute and chronic pain, providing promise for the approach to deliver a first-in-class non-opioid analgesic with a mechanism of action differentiated from current standard of care. This review will highlight the therapeutic potential of GlyT inhibitors as a novel class of analgesics, present recent advances reported for the field, and discuss the key challenges associated with the development of a GlyT inhibitor into a safe and effective agent to treat pain.

Psychometric Validation of the Psoriasis Symptoms and Impacts Measure (P-SIM), a Novel Patient-Reported Outcome Instrument for Patients with Plaque Psoriasis, Using Data from the BE VIVID and BE READY Phase 3 Trials.

INTRODUCTION: Plaque psoriasis can significantly impact patients' quality of life. We assessed psychometric properties of the Psoriasis Symptoms and Impacts Measure (P-SIM), developed to capture patients' experiences of signs, symptoms and impacts of psoriasis. METHODS: Pooled, blinded, 16-week data from 1002 patients in the BE VIVID and BE READY bimekizumab phase 3 trials were analysed. The suitability of the P-SIM missing score rule (weekly scores considered missing if ≥ 4 daily scores were missing) was assessed. Test-retest reliability was evaluated using intraclass correlation coefficients (ICCs). Convergent validity was assessed between P-SIM and relevant patient-reported outcome (PRO) (Dermatology Life Quality Index [DLQI], DLQI item 1 [skin symptoms], Patient Global Assessment of Psoriasis) and clinician-reported outcome (ClinRO) scores (Psoriasis Area and Severity Index [PASI], Investigator's Global Assessment [IGA]) at baseline and week 16. Known-groups validity was assessed, comparing P-SIM scores between patient subgroups predefined using PASI/IGA scores. Sensitivity to change over 16 weeks was evaluated; responder definition (RD) thresholds were explored. RESULTS: The missing score rule used did not impact P-SIM scores. Test-retest reliability analyses demonstrated excellent score reproducibility (ICC 0.91-0.98). Inter-item correlations at baseline and week 16 were strong (> 0.5), apart from "choice of clothing" with "skin pain" and "burning" at baseline (both 0.49). All P-SIM scores were moderately to strongly correlated with other outcomes, demonstrating convergent validity, apart from ClinROs (PASI, IGA) at baseline that had low variability. P-SIM scores discriminated known groups at week 16, confirming known-groups validity. Changes from baseline to week 16 in P-SIM and other clinically relevant outcomes were strongly correlated (> 0.5; weaker with ClinROs), establishing sensitivity to change. Anchor-based RD analyses determined a four-point P-SIM item score decrease as indicative of marked clinically meaningful improvement. CONCLUSION: P-SIM scores demonstrated good reliability, validity and sensitivity to change. A four-point RD threshold could be used to assess 16-week treatment effects. TRIAL REGISTRATION: BE VIVID: NCT03370133; BE READY: NCT03410992.

Identification of Transthyretin Tetramer Kinetic Stabilizers That Are Capable of Inhibiting the Retinol-Dependent Retinol Binding Protein 4-Transthyretin Interaction: Potential Novel Therapeutics for Macular Degeneration, Transthyretin Amyloidosis, and Their Common Age-Related Comorbidities.

Dissociation of transthyretin (TTR) tetramers may lead to misfolding and aggregation of proamyloidogenic monomers, which underlies TTR amyloidosis (ATTR) pathophysiology. ATTR is a progressive disease resulting from the deposition of toxic fibrils in tissues that predominantly presents clinically as amyloid cardiomyopathy and peripheral polyneuropathy. Ligands that bind to and kinetically stabilize TTR tetramers prohibit their dissociation and may prevent ATTR onset. Drawing from clinically investigated AG10, we designed a constrained congener (14) that exhibits excellent TTR tetramer binding potency, prevents TTR aggregation in a gel-based assay, and possesses desirable pharmacokinetics in mice. Additionally, 14 significantly lowers murine serum retinol binding protein 4 (RBP4) levels despite a lack of binding at that protein's all-trans-retinol site. We hypothesize that kinetic stabilization of TTR tetramers via 14 is allosterically hindering all-trans-retinol-dependent RBP4-TTR tertiary complex formation and that the compound could present ancillary therapeutic utility for indications treated with RBP4 antagonists, such as macular degeneration.

Bimekizumab versus Adalimumab in Plaque Psoriasis.

BACKGROUND: Bimekizumab is a monoclonal IgG1 antibody that selectively inhibits interleukin-17A and interleukin-17F. The efficacy and safety of bimekizumab as compared with the tumor necrosis factor inhibitor adalimumab in patients with moderate-to-severe plaque psoriasis have not been extensively examined. METHODS: We randomly assigned patients with moderate-to-severe plaque psoriasis in a 1:1:1 ratio to receive subcutaneous bimekizumab at a dose of 320 mg every 4 weeks for 56 weeks; bimekizumab at a dose of 320 mg every 4 weeks for 16 weeks, then every 8 weeks for weeks 16 to 56; or subcutaneous adalimumab at a dose of 40 mg every 2 weeks for 24 weeks, followed by bimekizumab at a dose of 320 mg every 4 weeks to week 56. The primary end points were a 90% or greater reduction from baseline in the Psoriasis Area and Severity Index (PASI) score (PASI 90 response; PASI scores range from 0 to 72, with higher scores indicating worse disease) and an Investigator's Global Assessment (IGA) score of 0 or 1, signifying clear or almost clear skin (scores range from 0 [clear skin] to 4 [severe disease]), at week 16. The analysis of the primary end points tested noninferiority at a margin of -10 percentage points and then tested for superiority. RESULTS: A total of 614 patients were screened, and 478 were enrolled; 158 patients were assigned to receive bimekizumab every 4 weeks, 161 to receive bimekizumab every 4 weeks and then every 8 weeks, and 159 to receive adalimumab. The mean age of the patients was 44.9 years; the mean PASI score at baseline was 19.8. At week 16, a total of 275 of 319 patients (86.2%) who received bimekizumab (both dose groups combined) and 75 of 159 (47.2%) who received adalimumab had a PASI 90 response (adjusted risk difference, 39.3 percentage points; 95% confidence interval [CI], 30.9 to 47.7; P<0.001 for noninferiority and superiority). A total of 272 of 319 patients (85.3%) who received bimekizumab and 91 of 159 (57.2%) who received adalimumab had an IGA score of 0 or 1 (adjusted risk difference, 28.2 percentage points; 95% CI, 19.7 to 36.7; P<0.001 for noninferiority and superiority). The most common adverse events with bimekizumab were upper respiratory tract infections, oral candidiasis (predominantly mild or moderate as recorded by the investigator), hypertension, and diarrhea. CONCLUSIONS: In this 56-week trial, bimekizumab was noninferior and superior to adalimumab through 16 weeks in reducing symptoms and signs of plaque psoriasis but was associated with a higher frequency of oral candidiasis and diarrhea. Longer and larger trials are required to determine the efficacy and safety of bimekizumab as compared with other agents in the treatment of plaque psoriasis. (Funded by UCB Pharma; BE SURE ClinicalTrials.gov number, NCT03412747.).

Bimekizumab versus Secukinumab in Plaque Psoriasis.

BACKGROUND: Bimekizumab is a monoclonal IgG1 antibody that selectively inhibits both interleukin-17A and interleukin-17F. The efficacy and safety of bimekizumab as compared with secukinumab, which selectively inhibits interleukin-17A alone, in patients with moderate-to-severe plaque psoriasis have not been extensively examined. METHODS: In this phase 3b trial, we randomly assigned patients with moderate-to-severe plaque psoriasis, in a 1:1 ratio, to receive bimekizumab subcutaneously at a dose of 320 mg every 4 weeks or secukinumab subcutaneously at a dose of 300 mg weekly to week 4, followed by every 4 weeks to week 48. At week 16, patients receiving bimekizumab underwent rerandomization, in a 1:2 ratio, to receive maintenance dosing every 4 weeks or every 8 weeks to week 48. The primary end point was 100% reduction from baseline in the Psoriasis Area and Severity Index (PASI) score at week 16. The primary analysis was first tested for the noninferiority of bimekizumab to secukinumab at a margin of -10 percentage points and then tested for superiority. RESULTS: A total of 1005 patients were screened and 743 were enrolled; 373 patients were assigned to receive bimekizumab and 370 to receive secukinumab. At week 16, a total of 230 patients (61.7%) in the bimekizumab group and 181 (48.9%) in the secukinumab group had a 100% reduction from baseline in the PASI score (PASI 100) (adjusted risk difference, 12.7 percentage points; 95% confidence interval [CI], 5.8 to 19.6); bimekizumab was shown to be noninferior and superior to secukinumab (P<0.001 for noninferiority and superiority). At week 48, a total of 250 patients (67.0%) treated with bimekizumab had a PASI 100 response, as compared with 171 patients (46.2%) treated with secukinumab (adjusted risk difference, 20.9 percentage points; 95% CI, 14.1 to 27.7; P<0.001). At the week 4 time point, 265 patients (71.0%) in the bimekizumab group had 75% or greater reduction from baseline in the PASI score, as compared with 175 patients (47.3%) in the secukinumab group (adjusted risk difference, 23.7; 95% CI, 17.0 to 30.4; P<0.001). Oral candidiasis occurred more often with bimekizumab (72 patients, 19.3%) than with secukinumab (11 patients, 3.0%). CONCLUSIONS: In patients with moderate-to-severe psoriasis, treatment with bimekizumab resulted in greater skin clearance than treatment with secukinumab over 16 and 48 weeks but was associated with oral candidiasis (predominantly mild or moderate as recorded by the investigator). Longer and larger trials are required to determine the comparative effect and risks of interleukin-17 inhibitors in psoriasis. (Funded by UCB Pharma; BE RADIANT ClinicalTrials.gov number, NCT03536884.).

Bimekizumab efficacy and safety in moderate to severe plaque psoriasis (BE READY): a multicentre, double-blind, placebo-controlled, randomised withdrawal phase 3 trial.

BACKGROUND: Bimekizumab is a monoclonal IgG1 antibody that selectively inhibits interleukin (IL)-17F in addition to IL-17A. This study investigated the efficacy and safety of bimekizumab in patients with moderate to severe plaque psoriasis, the effects of treatment withdrawal, and two maintenance dosing schedules over 56 weeks. METHODS: BE READY was a phase 3, multicentre, randomised, double-blind, placebo-controlled trial done at 77 sites (hospitals, clinics, private doctor's practices, and dedicated clinical research centres) in nine countries across Asia, Australia, Europe, and North America. Adult patients aged 18 years or older with moderate to severe plaque psoriasis were stratified by region and previous biologic exposure, and randomly assigned (4:1) to receive bimekizumab 320 mg every 4 weeks or placebo every 4 weeks by use of interactive response technology. Coprimary endpoints were the proportion of patients achieving 90% or greater improvement from baseline in the Psoriasis Area Severity Index (PASI90) and the proportion of patients achieving a score of 0 (clear) or 1 (almost clear) on the five-point Investigator's Global Assessment (IGA) scale at week 16 (non-responder imputation). Bimekizumab-treated patients achieving PASI90 at week 16 were re-allocated (1:1:1) to receive bimekizumab 320 mg every 4 weeks, every 8 weeks, or placebo for weeks 16-56. Efficacy analyses were done in the intention-to-treat population; the safety analysis set comprised all patients who received at least one dose of study treatment. This trial is registered with ClinicalTrials.gov (NCT03410992), and is now completed. FINDINGS: Between Feb 5, 2018, and Jan 7, 2020, 435 patients were randomly assigned to receive either bimekizumab 320 mg every 4 weeks (n=349) or placebo every 4 weeks (n=86). Coprimary endpoints were met: at week 16, 317 (91%) of 349 patients receiving bimekizumab 320 mg every 4 weeks achieved PASI90, compared with one (1%) of 86 patients receiving placebo (risk difference 89·8 [95% CI 86·1-93·4]; p<0·0001); and 323 (93%) of 349 patients receiving bimekizumab 320 mg every 4 weeks achieved an IGA score of 0 or 1 versus one (1%) of 86 patients receiving placebo (risk difference 91·5 [95% CI 88·0-94·9]; p<0·0001). Responses were maintained through to week 56 with bimekizumab 320 mg every 8 weeks and every 4 weeks. Treatment-emergent adverse events in the initial treatment period (up to week 16) were reported in 213 (61%) of 349 patients receiving bimekizumab 320 mg every 4 weeks and 35 (41%) of 86 patients receiving placebo every 4 weeks. From week 16 to week 56, treatment-emergent adverse events were reported in 78 (74%) of 106 patients receiving bimekizumab 320 mg every 4 weeks, 77 (77%) of 100 patients receiving bimekizumab 320 mg every 8 weeks, and 72 (69%) of 105 patients receiving placebo. INTERPRETATION: Bimekizumab showed high levels of response, which were durable over 56 weeks, with both maintenance dosing schedules (every 4 weeks and every 8 weeks). Moreover, bimekizumab was well tolerated, with no unexpected safety findings. Data presented here further support the therapeutic value of bimekizumab and inhibition of IL-17F in addition to IL-17A for patients with moderate to severe plaque psoriasis. FUNDING: UCB Pharma.

Bimekizumab versus ustekinumab for the treatment of moderate to severe plaque psoriasis (BE VIVID): efficacy and safety from a 52-week, multicentre, double-blind, active comparator and placebo controlled phase 3 trial.

BACKGROUND: There is an unmet need for a treatment for psoriasis that results in complete skin clearance with a reliably quick response. Bimekizumab is a monoclonal IgG1 antibody that selectively inhibits interleukin (IL)-17F in addition to IL-17A. We aimed to compare the efficacy and safety of bimekizumab with placebo and ustekinumab in patients with moderate to severe plaque psoriasis over 52 weeks. METHODS: BE VIVID was a multicentre, randomised, double-blind, active comparator and placebo controlled phase 3 trial done across 105 sites (clinics, hospitals, research units, and private practices) in 11 countries in Asia, Australia, Europe, and North America. Adults aged 18 years or older with moderate to severe plaque psoriasis (Psoriasis Area and Severity Index [PASI] score ≥12, ≥10% body surface area affected by psoriasis, and Investigator's Global Assessment [IGA] score ≥3 on a five point scale) were included. Randomisation was stratified by geographical region and previous exposure to biologics; patients, investigators, and sponsors were masked to treatment assignment. Patients were randomly assigned (4:2:1) using an interactive response technology to bimekizumab 320 mg every 4 weeks, ustekinumab 45 mg or 90 mg (baseline weight-dependent dosing) at weeks 0 and 4, then every 12 weeks, or placebo every 4 weeks. At week 16, patients receiving placebo switched to bimekizumab 320 mg every 4 weeks. All study treatments were administered as two subcutaneous injections. Coprimary endpoints were the proportion of patients with 90% improvement in the PASI (PASI90) and the proportion of patients with an IGA response of clear or almost clear (score 0 or 1) at week 16 (non-responder imputation). Efficacy analyses included the intention-to-treat population; safety analysis included patients who received at least one dose of study treatment. This trial was registered at ClinicalTrials.gov, NCT03370133 (completed). FINDINGS: Between Dec 6, 2017, and Dec 13, 2019, 735 patients were screened and 567 were enrolled and randomly assigned (bimekizumab 320 mg every 4 weeks n=321, ustekinumab 45 mg or 90 mg every 12 weeks n=163, placebo n=83). At week 16, 273 (85%) of 321 patients in the bimekizumab group had PASI90 versus 81 (50%) of 163 in the ustekinumab group (risk difference 35 [95% CI 27-43]; p<0·0001) and four (5%) of 83 in the placebo group (risk difference 80 [74-86]; p<0·0001). At week 16, 270 (84%) patients in the bimekizumab group had an IGA response versus 87 (53%) in the ustekinumab group (risk difference 30 [95% CI 22-39]; p<0·0001) and four (5%) in the placebo group (risk difference 79 [73-85]; p<0·0001). Over 52 weeks, serious treatment-emergent adverse events were reported in 24 (6%) of 395 patients in the bimekizumab group (including those who switched from placebo at week 16) and 13 (8%) of 163 in the ustekinumab group. INTERPRETATION: Bimekizumab was more efficacious than ustekinumab and placebo in the treatment of moderate to severe plaque psoriasis. The bimekizumab safety profile was consistent with that observed in previous studies. FUNDING: UCB Pharma.

Discovery of Bispecific Antagonists of Retinol Binding Protein 4 That Stabilize Transthyretin Tetramers: Scaffolding Hopping, Optimization, and Preclinical Pharmacological Evaluation as a Potential Therapy for Two Common Age-Related Comorbidities.

Accumulation of cytotoxic lipofuscin bisretinoids may contribute to atrophic age-related macular degeneration (AMD) pathogenesis. Retinal bisretinoid synthesis depends on the influx of serum all-trans-retinol (1) delivered via a tertiary retinol binding protein 4 (RBP4)-transthyretin (TTR)-retinol complex. We previously identified selective RBP4 antagonists that dissociate circulating RBP4-TTR-retinol complexes, reduce serum RBP4 levels, and inhibit bisretinoid synthesis in models of enhanced retinal lipofuscinogenesis. However, the release of TTR by selective RBP4 antagonists may be associated with TTR tetramer destabilization and, potentially, TTR amyloid formation. We describe herein the identification of bispecific RBP4 antagonist-TTR tetramer kinetic stabilizers. Standout analogue (±)-44 possesses suitable potency for both targets, significantly lowers mouse plasma RBP4 levels, and prevents TTR aggregation in a gel-based assay. This new class of bispecific compounds may be especially important as a therapy for dry AMD patients who have another common age-related comorbidity, senile systemic amyloidosis, a nongenetic disease associated with wild-type TTR misfolding.

Development and Content Validation of the Psoriasis Symptoms and Impacts Measure (P-SIM) for Assessment of Plaque Psoriasis.

INTRODUCTION: Patients with plaque psoriasis experience a variety of signs and symptoms that can impact daily life, which may not be evaluated by clinician-reported outcomes. This study aimed to develop and assess the content validity of a new patient-reported outcome (PRO) measure to capture patient experiences of the signs, symptoms and impacts of psoriasis and aid integration of the patient perspective in treatment benefit-risk decision-making. METHODS: The psoriasis symptoms and impacts measure (P-SIM) was developed based on a literature search and interviews with five clinical experts in psoriasis to identify frequent signs, symptoms and impacts of psoriasis. Hybrid concept elicitation, cognitive debriefing and usability testing interviews were conducted with moderate to severe psoriasis patients to evaluate the content validity and patient understanding of the preliminary P-SIM. The preliminary P-SIM was refined using initial quantitative analyses of phase 2b data from psoriasis patients to inform the removal of any items. RESULTS: A preliminary 19-item P-SIM was developed for administration on a hand-held electronic tablet device using a 0-10 numerical response scale over a 24-h recall period. Patient interviews and testing demonstrated most patients interpreted the items and responses as intended, would not re-word any items, felt the responses matched the items and rated the device as easy to use. After quantitative testing, five items were removed from the preliminary 19-item measure because of conceptual overlap, floor effects and/or skewed distributions to generate the final 14-item P-SIM. CONCLUSIONS: The P-SIM questionnaire has good content validity; patients reported it was easy to understand and reflective of their experiences. Following psychometric validation, the P-SIM may be a useful PRO measure for capturing the signs, symptoms and impacts of psoriasis and may support clinician-reported outcomes when assessing treatment benefits in clinical trials.

Bimekizumab for patients with moderate to severe plaque psoriasis: 60-week results from BE ABLE 2, a randomized, double-blinded, placebo-controlled, phase 2b extension study.

BACKGROUND: Dual neutralization of both interleukin 17A and 17F with the monoclonal antibody bimekizumab may have greater efficacy in psoriasis than neutralization of interleukin 17A alone. OBJECTIVE: To provide longer-term efficacy and safety data for bimekizumab from a phase 2b extension study in patients with moderate to severe psoriasis (BE ABLE 2). METHODS: After the 12-week initial study (BE ABLE 1), patients who had a 90% improvement in Psoriasis Area and Severity Index (PASI 90) at week 12 received bimekizumab 64, 160, or 320 mg for an additional 48 weeks (60 weeks in total). The primary objective was safety. RESULTS: Across all dose groups (N = 217), initial PASI 90 responders generally maintained high levels of efficacy through week 60: PASI 90, 80% to 100%; 100% improvement in PASI, 69% to 83%; Investigator's Global Assessment score 0 or 1, 78% to 100% (all nonresponder imputation). Incidence of serious treatment-emergent adverse events was 15/217 (6.9%). No cases of inflammatory bowel disease, major adverse cardiovascular events, or suicidal ideation or behavior were reported. LIMITATIONS: Low numbers in the bimekizumab 64 mg group (n = 15). The majority of 60-week data reported here are primarily for the week 12 PASI 90 responders only. CONCLUSION: Bimekizumab response rates were maintained through week 60. A substantial proportion of patients achieved complete skin clearance. Bimekizumab was generally well tolerated.

Photoswitchable ORG25543 Congener Enables Optical Control of Glycine Transporter 2.

Glycine neurotransmission in the dorsal horn of the spinal cord plays a key role in regulating nociceptive signaling, but in chronic pain states reduced glycine neurotransmission is associated with the development of allodynia and hypersensitivity to painful stimuli. This suggests that restoration of glycine neurotransmission may be therapeutic for the treatment of chronic pain. Glycine transporter 2 inhibitors have been demonstrated to enhance glycine neurotransmission and provide relief from allodynia in rodent models of chronic pain. In recent years, photoswitchable compounds have been developed to provide the possibility of controlling the activity of target proteins using light. In this study we have developed a photoswitchable noncompetitive inhibitor of glycine transporter 2 that has different affinities for the transporter at 365 nm compared to 470 nm light.

Stringent response governs the oxidative stress resistance and virulence of Francisella tularensis.

Francisella tularensis is a Gram-negative bacterium responsible for causing tularemia in the northern hemisphere. F. tularensis has long been developed as a biological weapon due to its ability to cause severe illness upon inhalation of as few as ten organisms and, based on its potential to be used as a bioterror agent is now classified as a Tier 1 Category A select agent by the CDC. The stringent response facilitates bacterial survival under nutritionally challenging starvation conditions. The hallmark of stringent response is the accumulation of the effector molecules ppGpp and (p)ppGpp known as stress alarmones. The relA and spoT gene products generate alarmones in several Gram-negative bacterial pathogens. RelA is a ribosome-associated ppGpp synthetase that gets activated under amino acid starvation conditions whereas, SpoT is a bifunctional enzyme with both ppGpp synthetase and ppGpp hydrolase activities. Francisella encodes a monofunctional RelA and a bifunctional SpoT enzyme. Previous studies have demonstrated that stringent response under nutritional stresses increases expression of virulence-associated genes encoded on Francisella Pathogenicity Island. This study investigated how stringent response governs the oxidative stress response of F. tularensis. We demonstrate that RelA/SpoT-mediated ppGpp production alters global gene transcriptional profile of F. tularensis in the presence of oxidative stress. The lack of stringent response in relA/spoT gene deletion mutants of F. tularensis makes bacteria more susceptible to oxidants, attenuates survival in macrophages, and virulence in mice. This work is an important step forward towards understanding the complex regulatory network underlying the oxidative stress response of F. tularensis.

Design, Synthesis, and Preclinical Efficacy of Novel Nonretinoid Antagonists of Retinol-Binding Protein 4 in the Mouse Model of Hepatic Steatosis.

Retinol-binding protein 4 (RBP4) serves as a transporter for all- trans-retinol (1) in the blood, and it has been proposed to act as an adipokine. Elevated plasma levels of the protein have been linked to diabetes, obesity, cardiovascular diseases, and nonalcoholic fatty liver disease (NAFLD). Recently, adipocyte-specific overexpression of RBP4 was reported to cause hepatic steatosis in mice. We previously identified an orally bioavailable RBP4 antagonist that significantly lowered RBP4 serum levels in Abca4-/- knockout mice with concomitant normalization of complement system protein expression and reduction of bisretinoid formation within the retinal pigment epithelium. We describe herein the discovery of novel RBP4 antagonists 48 and 59, which reduce serum RBP4 levels by >80% in mice upon acute oral dosing. Furthermore, 59 demonstrated efficacy in the transgenic adi-hRBP4 murine model of hepatic steatosis, suggesting that RBP4 antagonists may also have therapeutic utility for the treatment of NAFLD.