Selective Kinase Research Articles

Design and optimization of selective and potent CDK9 inhibitors with flavonoid scaffold for the treatment of acute myeloid leukemia

Acute myeloid leukemia (AML) is a prevalent hematological tumor associated with a high morbidity and mortality rate. CDK9, functioning as a pivotal transcriptional regulator, facilitates transcriptional elongation through phosphorylation of RNA polymerase II, which further governs the protein levels of Mcl-1 and c-Myc. Therefore, CDK9 has been considered as a promising therapeutic target for AML treatment. Here, we present the design, synthesis, and evaluation of CDK9 inhibitors bearing a flavonoid scaffold. Among them, compound 21a emerged as a highly selective CDK9 inhibitor (IC50 = 6.7 nM), exhibiting over 80-fold selectivity towards most other CDK family members and high kinase selectivity. In Mv4-11 cells, 21a effectively hindered cell proliferation (IC50 = 60 nM) and induced apoptosis by down-regulating Mcl-1 and c-Myc. Notably, 21a demonstrated significant inhibition of tumor growth in the Mv4-11 xenograft tumor model. These findings indicate that compound 21a holds promise as a potential candidate for treating AML.

NTRK fusion events and targeted treatment of advanced radioiodine refractory thyroid cancer

PurposePathogenic fusion events involving neurotrophic receptor tyrosine kinase (NTRK) have been described in ~ 2% of differentiated thyroid cancer (DTC). The selective tropomyosin receptor kinase (TRK) inhibitors entrectinib and larotrectinib have been approved in a tumor agnostic manner based on phase 1/2 clinical trials. In a real-world setting at five referral centers, we aimed to describe the prevalence of NTRK gene fusions and the efficacy and safety of TRK inhibitor treatment for non-medullary, advanced thyroid cancer (TC).MethodsA total of 184 TC patients with testing for NTRK gene fusions were included. Progression-free survival (PFS) and overall survival (OS) probabilities were estimated using the Kaplan–Meier method in six patients with NTRK fusion-positive TC who underwent TRK inhibitor therapy.Results8/184 (4%) patients harbored NTRK gene fusions. Six patients with radioiodine (RAI)-refractory TC harboring NTRK1 (n = 4) and NTRK3 (n = 2) gene fusions were treated with larotrectinib. Five patients (83%) had received ≥ 1 prior systemic therapy and one patient did not receive prior systemic therapy. All patients had morphologically progressive disease before treatment initiation. Objective response rate was 83%, including two complete remissions. Median PFS from start of TRK inhibitor treatment was 23 months (95% confidence interval [CI], 0–57.4) and median OS was not reached (NR) (95% CI, NR). Adverse events were of grade 1–3.ConclusionThe prevalence of NTRK gene fusions in our cohort of RAI-refractory TC is slightly higher than reported for all TC patients. Larotrectinib is an effective treatment option in the majority of NTRK gene fusion-positive advanced TC patients after prior systemic treatment and has a favorable safety profile.

Design, synthesis, and biological evaluation of 1,6-naphthyridine-2-one derivatives as novel FGFR4 inhibitors for the treatment of colorectal cancer

Aberrant FGFR4 signaling has been implicated in the development of several cancers, making FGFR4 a promising target for cancer therapy. Several FGFR4-selective inhibitors have been developed, yet none of them have been approved. Herein, we report a novel series of 1,6-naphthyridine-2-one derivatives as potent and selective inhibitors targeting FGFR4 kinase. Preliminary structure-activity relationship analysis was conducted. The screening cascades revealed that 19g was the preferred compound among the prepared series. 19g demonstrated excellent kinase selectivity and substantial cytotoxic effect against all tested colorectal cancer cell lines. 19g induced significant tumor inhibition in a HCT116 xenograft mouse model without any apparent toxicity. Notably, 19g exhibited excellent potency in disrupting the phosphorylation of FGFR4 and downstream signaling proteins mediated by FGF18 and FGF19. Compound 19g might be a potential antitumor drug candidate for the treatment of colorectal cancer.

Preclinical Pharmacokinetics and in vitro Metabolism of FHND5071, a Novel Selective RET Kinase Inhibitor.

Rearranged during transfection (RET) is a transmembrane receptor tyrosine kinase that plays a crucial role in tumorigenesis. FHND5071, a potent and selective RET kinase inhibitor, could exert antitumor effects by inhibiting RET autophosphorylation. The present work aims to profile the pharmacokinetics of FHND5071 in in vivo and in vitro experiments as a ground work for further clinical research. The absorption, distribution, metabolism, and excretion properties of FHND5071 were examined, along with metabolite production and cytochrome P450 (CYP) phenotyping assay. Additionally, plasma protein binding and pharmacokinetics in mice were investigated. Microsomal stability assay corroborated moderate to high clearance of FHND5071, and the use of UPLC-Q-TOF-MS identified a total of six metabolites and suggested a possible metabolic pathway involving oxidation, demethylation, and N-dealkylation. Primary contributors to the CYP-mediated metabolism of FHND5071 were found to be CYP2C8 and CYP3A4, and FHND5071 displayed low permeability and acted as a substrate for the P-glycoprotein (P-gp). FHND5071 had a moderate to high binding in plasma and exhibited a moderate absorption degree (absolute bioavailability > 60%) The distribution of FHND5071 in mouse tissues was rapid (mostly peaking at 1-4 h) and wide (detectable in almost all tissues and organs), with the highest exposure in the spleen. A small fraction of FHND5071 was excreted via the urine and feces, and a presumed metabolic pathway involving 20 metabolites in mice is proposed. Pharmacokinetic characteristics of FHND5071 were systemically profiled, which may lay the foundation for further clinical development as a drug candidate.

Activity of ceritinib in crizotinib-resistant ROS1-rearranged non-small-cell lung cancer patients.

As a second-generation selective oral anaplastic lymphoma kinase inhibitor, ceritinib is an effective first-line treatment for c-ros oncogene 1 (ROS1)-rearranged non-small-cell lung cancer (NSCLC). Its efficacy and safety for the treatment of crizotinib-resistant ROS1-rearranged NSCLC were explored in the study. A retrospective single-center study was conducted to investigate the efficacy of ceritinib in crizotinib-resistant ROS1-rearranged NSCLC. The objective response rate was the primary objective, while the disease control rate, progression-free survival and adverse events were secondary objectives. From December 2015 to October 2021, a total of 246 patients with ROS1-rearranged NSCLC were screened, 12 (4.9%) of whom were treated with ceritinib after the development of crizotinib resistance. Among the 12 crizotinib-resistant patients included, 3 displayed the efficacy of partial response and 3 had the efficacy of stable condition. The objective response rate, disease control rate and median progression-free survival of all patients were 25% (95% confidence interval [CI]: -3.7% to 53.7%; 3 of 12 patients), 50% (95% CI: 16.8% to 83.2%; 6 of 12 patients), and 10.5 months (95% CI, 5.7 to 15.3 months), respectively. In addition, of the 6 patients with brain metastases, an intracranial disease control rate of 66.7% (95% CI:12.5% to 120.9%) was obtained. The research results reveal that ceritinib can be a treatment option for ROS1-rearranged NSCLC patients after the development of crizotinib resistance.

Discovery of novel and selective SIK2 inhibitors by the application of AlphaFold structures and generative models

Salt-inducible kinase 2 (SIK2) has been recognized as a potential target for anti-inflammation and anti-cancer therapy. In this paper, based on the binding pose of the reported compound (GLPG-3970, 3) with AlphaFold protein structure, a series of hinge cores were generated via AI-generative models (Chemistry42). After the molecular docking, synthesis, and biological evaluation, a hit molecule (7f) targeting SIK2 was obtained with a novel scaffold. Further SAR exploration led to the discovery of compound 8g with superior potency against SIK2 compared with the reported inhibitors. Furthermore, 8g also demonstrated excellent selectivity over other AMPK kinases, favorable in vitro ADMET profiles and decent cellular activities. This work provides an alternative approach to the discovery of novel and selective kinase inhibitors.

Selective targeting of Aurora kinase B over A: Uncovering the structural basis for inhibitor specificity through molecular dynamics simulations

As promising therapeutic targets for various types of cancers, Aurora kinases A and B share high sequence and structural similarity, posing a challenge for designing subtype-selective small-molecule inhibitors. Since Aurora kinase A functions as both an oncogene and a haploinsufficient tumor suppressor, selectively inhibiting Aurora kinase B with highly specific inhibitors offers a less toxic anti-cancer strategy. However, the molecular mechanism governing ligand selectivity for Aurora kinase B over A remains unclear. In this study, we used Barasertib, an experimentally validated ligand with 1000-fold selectivity for Aurora kinase B over A, as a template molecule to investigate the selectivity mechanism through molecular dynamics simulations and binding free energy analyses. Our studied showed that in the ATP-binding pocket, the hinge residue Arg159 (−2.21 kcal/mol), exclusive to Aurora kinase B, significantly contributed to Barasertib binding, whereas no such binding occurred with the corresponding residue Leu215 (−0.10 kcal/mol) in Aurora kinase A. In the hydrophobic back pocket, the sum of binding free energies for key residues Lys106, Glu125, and Asp218 in Aurora kinase B (−4.02 kcal/mol) was substantially lower than that (7.89 kcal/mol) for the corresponding residues Lys162, Glu181, and Asp274 in Aurora kinase A. This finding suggests that binding interactions at the hydrophobic back pocket play a crucial role in Barasertib's selectivity for Aurora kinase B over A. Interestingly, in contrast to the complexes without partner proteins, the binding of partner proteins in both Aurora kinase A and B models induced the aC helix and the beta sheets in the N-lobe to move inward towards the ATP-binding pocket, resulting in a smaller hydrophobic back pocket and unfavorable Barasertib binding. In summary, our results demonstrate how differential ligand behavior arises from a complex interplay of subtle but relevant structural differences upon binding to distinct kinase subtypes. The insights into the structural determinants of subtype selectivity will facilitate the development of highly selective and potent Aurora kinase B inhibitors as drug candidates for cancer therapy.

Management of radioiodine refractory differentiated thyroid cancer: the Latin American perspective.

Radioiodine (RAI) refractory differentiated thyroid cancer is an uncommon and challenging situation that requires a multidisciplinary approach to therapeutic strategies. The definition of RAI-refractoriness is usually a clear situation in specialized centers. However, the right moment for initiation of multikinase inhibitors (MKI), the time and availability for genomic testing, and the possibility of prescribing MKI and selective kinase inhibitors differ worldwide.Latin America (LA) refers to the territories of the world that stretch across two regions: North America (including Central America and the Caribbean) and South America, containing 8.5% of the world's population. In this manuscript, we critically review the current standard approach recommended for patients with RAI refractory differentiated thyroid cancer, emphasizing the challenges faced in LA. To achieve this objective, the Latin American Thyroid Society (LATS) convened a panel of experts from Brazil, Argentina, Chile, and Colombia. Access to MKI compounds continues to be a challenge in all LA countries. This is true not only for MKI but also for the new selective tyrosine kinase inhibitor, which will also require genomic testing, that is not widely available. Thus, as precision medicine advances, significant disparities will be made more evident, and despite efforts to improve coverage and reimbursement, molecular-based precision medicine remains inaccessible to most of the LA population. Efforts should be undertaken to alleviate the discrepancies between the current state-of-the-art care for RAI-refractory differentiated thyroid cancer and the present situation in Latin America.

P64 Efficacy of baricitinib in patients with different degrees of severe alopecia areata: 52-week results from BRAVE-AA1 and BRAVE-AA2

Abstract Baricitinib, an oral selective Janus kinase (JAK)1/JAK2 inhibitor, demonstrated efficacy in adults with severe alopecia areata (AA) over 36 weeks in two phase III, randomized, double-blind, placebo-controlled trials, BRAVE-AA1 (NCT03570749) and BRAVE-AA2 (NCT03899259). Using integrated data from the long-term extension periods of both trials, we report treatment response to baricitinib by the AA severity subgroup based on the Severity of Alopecia Tool (SALT) score over 52 weeks. Patients randomized to baricitinib at baseline (n = 855) retained their treatment allocation (2 mg/4 mg) through to week 52 in both trials and were included in week 52 analyses; placebo nonresponders were rescued at week 36. Severity of AA at baseline was defined as severe (SALT score 50–94) or very severe (SALT score 95–100). Key inclusion criteria were SALT score ≥ 50, current AA episode lasting > 6 months to < 8 years without spontaneous improvement within 6 months prior to screening, and no previous inadequate response to oral JAK inhibitors. Efficacy endpoints included the proportion of patients achieving a SALT score ≤ 20 and the proportion of patients achieving Clinician-Reported Outcome (ClinRO) Measure for Eyebrow/Eyelash Hair Loss™ 0,1 (no, minimal gaps) with ≥ 2-point improvement from baseline among patients with baseline scores 2,3 (significant gaps, no notable eyebrows/eyelashes). Analyses were presented descriptively for each subgroup up to week 52. Nonresponder imputation was used for missing data. Data collected after permanent study drug discontinuation or at remote visits due to the COVID-19 pandemic were excluded. In total, 1200 patients were enrolled (BRAVE-AA1, n = 654; BRAVE-AA2, n = 546). At baseline, the overall mean (SD) age was 37.5 (12.9) years; 60.7% were female and 46.8% and 53.2% of patients had severe and very severe AA, respectively. At week 52, a SALT score ≤ 20 was achieved by 36.1% and 51.2% of patients on baricitinib 2 mg and baricitinib 4 mg, respectively, with severe AA and 12.4% and 27.7% of patients on baricitinib 2 mg and baricitinib 4 mg, respectively, with very severe AA. Eyebrow/Eyelash Hair Loss™ scores 0,1 with ≥ 2-point improvement from baseline at week 52 were achieved by 19.4% and 26.0% (baricitinib 2 mg) and 37.5% and 38.5% (baricitinib 4 mg) of patients with severe AA and 24.3% and 25.3% (baricitinib 2 mg) and 47.6% and 48.1% (baricitinib 4 mg) of patients with very severe AA. Following 52 weeks of treatment with both baricitinib doses, clinical responses of SALT score ≤ 20 were observed both in patients with severe and very severe AA. Proportions of patients achieving full coverage or minimal gaps in eyebrows and eyelashes were similar at week 52, regardless of scalp hair-loss severity. Funding sources: Eli Lilly and Company.

Acne Among Japanese Patients with Atopic Dermatitis Receiving Upadacitinib in the Phase3 RisingUp Study.

Upadacitinib, an oral selective Janus kinase (JAK) inhibitor, is used to treat moderate-to-severe atopic dermatitis (AD). Acne is the most common treatment-emergent adverse event in patients with AD treated with upadacitinib. In this post hoc analysis, we describe the acne events in Japanese patients with AD who received upadacitinib during the RisingUp study. In this phase3, double-blind, 3-year trial evaluating the safety and efficacy of upadacitinib 15mg or 30mg in Japanese patients with moderate-to-severe AD, patients were randomized 1:1:1 to receive upadacitinib 15mg, 30mg, or placebo for up to 16weeks. At week16, placebo-treated patients were re-randomized 1:1 to receive upadacitinib 15mg or 30mg. The incidence, characteristics, and management of treatment-emergent acne events up to the 52-week cutoff date were summarized. Among 272 patients in this analysis, the incidence of acne was higher in patients receiving upadacitinib compared with patients who received placebo. The rate of acne was higher in patients receiving upadacitinib 30mg (32.4%) compared with those taking upadacitinib 15mg (17.3%) during the long-term treatment period. All cases of acne were mild or moderate; no cases led to study drug discontinuation. The mean (range) of acne onset was 135.4 (7-465) days after starting study drug. Most acne occurred on the face; inflammatory papules were the most common morphology. Risk factors for acne included relevant concomitant medications (e.g., corticosteroids) started before acne onset and family and personal history of acne. Acne was generally managed with topical treatments. Mild or moderate acne reported in Japanese patients with AD receiving upadacitinib occurred in a dose-dependent manner and had a variable onset time. Acne was readily managed with topical treatments. Patients and clinicians should be aware of the risk of acne associated with upadacitinib treatment for AD. ClinicalTrials.gov identifier, NCT03661138.

AiKPro: deep learning model for kinome-wide bioactivity profiling using structure-based sequence alignments and molecular 3D conformer ensemble descriptors

The discovery of selective and potent kinase inhibitors is crucial for the treatment of various diseases, but the process is challenging due to the high structural similarity among kinases. Efficient kinome-wide bioactivity profiling is essential for understanding kinase function and identifying selective inhibitors. In this study, we propose AiKPro, a deep learning model that combines structure-validated multiple sequence alignments and molecular 3D conformer ensemble descriptors to predict kinase-ligand binding affinities. Our deep learning model uses an attention-based mechanism to capture complex patterns in the interactions between the kinase and the ligand. To assess the performance of AiKPro, we evaluated the impact of descriptors, the predictability for untrained kinases and compounds, and kinase activity profiling based on odd ratios. Our model, AiKPro, shows good Pearson’s correlation coefficients of 0.88 and 0.87 for the test set and for the untrained sets of compounds, respectively, which also shows the robustness of the model. AiKPro shows good kinase-activity profiles across the kinome, potentially facilitating the discovery of novel interactions and selective inhibitors. Our approach holds potential implications for the discovery of novel, selective kinase inhibitors and guiding rational drug design.

An effective kinase inhibition strategy for metastatic recurrent childhood medulloblastoma.

Medulloblastomas (MBs) constitute the most common malignant brain tumor in children and adolescents. MYC-amplified Group 3 MBs are characterized by disease recurrence, specifically in the leptomeninges, whereby patients with these metastatic tumors have a mortality rate nearing 100%. Despite limited research on such tumors, studies on MB metastases at diagnosis suggest targeting kinases to be beneficial. To identify kinase inhibitors that eradicate cells driving therapy evasion and tumor dissemination, we utilized our established patient-derived xenograft (PDX) mouse-adapted therapy platform that models human MB metastatic recurrences following standard chemoradiotherapy. High-throughput screens of 640 kinase inhibitors were conducted against cells isolated from mouse spines in the PDX model and human fetal neural stem cells to reveal compounds that targeted these treatment-refractory, metastatic cells, whilst sparing healthy cells. Blood-brain barrier permeability assays and additional in vitro experimentation helped select top candidates for in vivo studies. Recurrent Group 3MB PDX spine cells were therapeutically vulnerable to a selective checkpoint kinase 1 (CHK1) inhibitor and small molecular inhibitor of platelet-derived growth factor receptor beta (PDGFRβ). Inhibitor-treated cells showed a significant reduction in MB stem cell properties associated with treatment failure. Mice also demonstrated survival advantage when treated with a CHK1 inhibitor ex vivo. We identified CHK1 and PDGFRβ inhibitors that effectively target MB cells fueling treatment-refractory metastases. With limited research on effective therapies for Group 3MB metastatic recurrences, this work highlights promising therapeutic options to treat these aggressive tumors. Additional studies are warranted to investigate these inhibitors' mechanisms and recommended in vivo administration.

Pharmacokinetics of baricitinib in critically ill COVID-19 patients

BackgroundThe use of the selective Janus Kinase 1/2 inhibitor baricitinib has shown a survival benefit in mechanically ventilated COVID-19 patients but this is not without adverse drug reactions. Although critically ill patients are at risk of altered drug exposure, data on baricitinib pharmacokinetics (PK) are scarce. This study describes real-life baricitinib plasma exposure in critically ill COVID-19 patients. MethodsThis retrospective observational study was conducted in critically ill patients with COVID-19 treated with baricitinib 4 mg/day. Plasma concentrations were measured at predose (C0), 1 h (C1) and 3 h (C3) after the drug intake. PK and area under the curve (AUC) were estimated using non-compartmental pharmacokinetic analysis. ResultsSeven patients contributed to 22 baricitinib plasma concentration measurements after a median [range] of 3 days [2–3] of treatment. Median baricitinib plasma concentrations were 2.2 ng/mL [1.4–8.0], 24.0 ng/mL [4.9–37.3] and 14.1 ng/mL [8.3–15.1] for trough (C0), C1 and C3 concentrations respectively. The median AUC 0–24 h was 188.8 ng.h/mL [141.3–236.3]. No difference was observed in C0 and C1 when comparing patients according to body mass index < or > 30. The patient with the lowest glomerular filtration rate (74 mL/min) had the highest baricitinib trough concentration. Overall, 2 patients had liver function test perturbation and both of them had atypical PK with delayed time to reach maximum concentration. ConclusionHigh inter-patient variability and relatively low baricitinib trough concentrations and AUC were observed in critically ill COVID-19 patients receiving the usual dosage of 4 mg/day. This preliminary study encourages further exploration of the concentration-effect relationship of baricitinib in this clinical context.

Baricitinib provides rapid and sustained improvements in absolute EASI and SCORAD outcomes in adults with moderate-to-severe atopic dermatitis

BackgroundBaricitinib is an oral selective Janus kinase 1/2 inhibitor approved for moderate-to-severe atopic dermatitis (AD) in adults.ObjectivesTo evaluate absolute Eczema Area and Severity Index (EASI) and SCORing of Atopic Dermatitis (SCORAD) outcomes over 16 weeks and to link disease severity categories to quality of life (QoL) improvements.MethodsThis post-hoc analysis included patients enrolled in Phase3 monotherapy (BREEZE-AD1/AD2) and topical corticosteroid (TCS) combination therapy (BREEZE-AD7) trials and analyzed baricitinib 2 and 4 mg vs. placebo. Categorical outcomes were analyzed using Fisher’s exact test.ResultsSignificantly more baricitinib-treated patients reached EASI ≤ 7 and SCORAD < 25 as early as week 1 in monotherapy and week 2 in TCS combination therapy, compared to placebo. Significant response vs. placebo was sustained until week 16 for EASI ≤ 7 (AD1/2 [p-value vs. placebo]: 2 mg = 19.9%, 4 mg = 25.4% [p = 0.001] and AD7: 2 mg = 40.4% [p = 0.087], 4 mg = 48.6% [p = 0.003]) and SCORAD < 25 (AD1/2: 2 mg = 12.2%, 4 mg = 19.4% [p = 0.001] and AD7: 2 mg = 30.3% [p = 0.025], 4 mg = 34.2% [p = 0.004]) severity categories. These effects were accompanied by rapid improvements in QoL.ConclusionBaricitinib-treated patients rapidly achieved recommended absolute EASI and SCORAD treatment outcomes which were sustained until week 16. Improvements in QoL were greater than EASI severity categories reflected, indicating that physician-assessed scores do not necessarily correlate with patients’ impression of AD severity.

Discovery of novel hypoxia-activated, nitroimidazole constructed multi-target kinase inhibitors on the basis of AZD9291 for the treatment of human lung cancer

A group of 4-(1-methyl-1H-indol-3-yl)pyrimidin-2-amine derivatives containing a hypoxia-activated nitroimidazole group were designed as EGFR inhibitors. Among this series, A14 was identified as the optimal compound, exhibiting potent anti-proliferative activities against H1975 and HCC827 cells. Under hypoxic condition, the anti-proliferative activities of A14 improved by 4–6-fold (IC50 < 10 nM), indicating its hypoxia-selectivity. A14′s high potency may be attributed to its inhibition against multiple kinases, including EGFR, JAK2, ROS1, FLT3, FLT4 and PDGFRα, which was confirmed by binding assays on a panel of 30 kinases. Furthermore, A14 exhibited good bio-reductive property and could bind with nucleophilic amino acids after being activated under hypoxic conditions. With its anti-proliferative activities and selectivity for hypoxia and oncogenic kinases, A14 shows promise as a multi-target kinase inhibitor for cancer therapy.

396 Rapid, substantial and sustained reduction of itch in adults with atopic dermatitis applying ruxolitinib cream 1.5% (SCRATCH-AD)

Abstract Atopic dermatitis (AD) is a chronic, recurring, highly pruritic inflammatory skin disease. The mechanical injury from scratching contributes to skin inflammation and barrier disruption, exacerbating the itch–scratch cycle, which perpetuates the disease. Ruxolitinib cream is a topical formulation of ruxolitinib, a selective Janus kinase (JAK) 1/JAK2 inhibitor, approved in the USA for the short-term and noncontinuous chronic treatment of mild to moderate AD in patients ≥12 years old whose disease is not adequately controlled with topical prescription therapies or when those therapies are not advisable. In two pivotal phase 3 trials (TRuE-AD1 and TRuE-AD2) in adolescents and adults with AD, ruxolitinib cream 1.5% demonstrated significant improvement in itch vs. vehicle cream, as early as 12 h after initial application. A phase 2, open-label, single-site study (SCRATCH-AD; NCT04839380) was undertaken to further understand the short-term clinical benefits of ruxolitinib cream to control pruritus and reduce disease severity in participants with AD. Participants enrolled in the study were aged 18–65 years with AD for ≥6 months, with chronic itch related to AD for ≥3 months, 1–20% affected body surface area (BSA), Investigator’s Global Assessment (IGA) of ≥2 and a peak pruritus numerical rating scale (PP-NRS) score ≥4 at baseline. Participants applied ruxolitinib cream 1.5% twice daily to all lesions identified at baseline and any new lesions for 28 days. The primary endpoint was change from baseline in PP-NRS at Day 2 (24 h after the first application of ruxolitinib cream). Secondary endpoints included change from baseline in modified PP-NRS (mPP-NRS; current itch intensity) at 15 and 30 min and at 1, 2, 4, 6 and 12 h post-treatment on Day 1, as well as change from baseline in PP-NRS from Days 3 through 29, change from baseline in IGA at Days 8, 15 and 29, and safety. The primary analysis included 46 participants in the modified intent-to-treat population. Median age (range) was 30 (18–64) years; 69.6% were female, and 89.1% were White. At baseline, mean (SD) affected BSA was 9.5% (4.94%), mean (SD) 7-day average PP-NRS score was 6.7 (1.36), mean (SD) pretreatment mPP-NRS score was 6.4 (1.72) and 89.1% had an IGA score of 3. The mean (SD) change from baseline in PP-NRS on Day 2 was –3.4 (1.85). The mean (SD) change from baseline in mPP-NRS at 15 min post-treatment was –2.3 (2.34), peaking at –4.2 (2.12) at 4 h post-treatment and was –3.1 (2.00) at 12 h post-treatment. The mean (SD) change from baseline PP-NRS continued to increase through Day 29 [–5.7 (1.60)]. The mean (SD) changes from baseline in IGA score on Days 8, 15 and 29 were –1.4 (0.73), –2.0 (0.87) and –2.2 (0.90), respectively. Treatment-emergent adverse events (TEAEs) were reported in 15/49 (30.6%) participants (none were serious); one participant had a treatment-related TEAE [grade 1 application site reaction (acne)]. No participant discontinued treatment due to TEAE. Lesional skin treated with ruxolitinib cream 1.5% twice daily showed substantial decrease in transepidermal water loss from a baseline mean (SD) score of 35.0 (17.47) to 13.1 (4.42) over 4 weeks, thus reaching similar levels to the nonlesional skin score of 12.7 (4.56) at Day 29. Participants with AD applying ruxolitinib cream 1.5% experienced rapid, substantial improvement in itch, which was sustained and further improved through 28 days of treatment. Itch reduction was observed as early as 15 min, and peak reduction was observed at 4 h after first cream application. These results further demonstrate the clinical benefits and are consistent with the established data on ruxolitinib cream as an effective, well-tolerated topical treatment for AD.

425 Effect of upadacitinib on SCORAD intensity items: analysis from the Measure Up 1 and Measure Up 2 studies

Abstract Atopic dermatitis (AD) is a chronic, inflammatory disease characterized by typical clinical signs (erythema, edema/papulation, oozing/crusting, excoriation, lichenification and dryness) and prominent itch that can markedly impact a patient’s sleep and quality of life (QoL). Upadacitinib is a selective oral Janus kinase (JAK) inhibitor with greater inhibitory potency for JAK1 vs. JAK2, JAK3 and tyrosine kinase 2. The SCORing Atopic Dermatitis (SCORAD) measure is a validated assessment tool that evaluates the extent of disease based on the area of the body affected, intensity of clinical signs of AD, and itch and sleeplessness due to AD. In this integrated post hoc analysis of the Measure Up 1 and Measure Up 2 studies, we compared the effects of upadacitinib (15 and 30 mg) vs. placebo on the intensity of the individual signs assessed by the SCORAD at Week 2 and Week 16. Measure Up 1 and Measure Up 2 are replicate phase 3 multicenter, randomized, double-blind studies comparing the safety and efficacy of upadacitinib 15 mg and upadacitinib 30 mg to placebo in adolescent and adult patients with moderate-to-severe AD. Patients were randomized to upadacitinib 15 mg, upadacitinib 30 mg or placebo orally once daily. All patients received additive-free, bland emollient twice daily for at least 7 days before baseline and during the study until week 16. The current study assessed the intensity of the six clinical signs assessed by the SCORAD (erythema, edema/papulation, oozing/crusting, excoriation, lichenification and dryness with a 4-level rating scale of none, mild, moderate and severe). The proportions of patients achieving resolution (i.e. an intensity rating of ‘none’) of each clinical sign at Week 2 and Week 16 were evaluated among patients with mild, moderate or severe intensity at baseline. Resolution rates were compared using the Mantel–Haenszel test. Missing data were handled using nonresponder imputation. A total of 1679 participants (placebo, 558; upadacitinib 15 mg, 557; upadacitinib 30 mg, 564) were included in the analysis of integrated data from the Measure Up 1 and Measure Up 2 studies. Differences in the proportion of patients achieving resolution for both upadacitinib doses (15 mg/30 mg) vs. placebo were observed at Week 2 (P &amp;lt; 0.0001) for erythema (3.1%/6.0% vs. 0.0%), edema/papulation (13.1%/16.6% vs. 1.3%), oozing/crusting (49.8%/59.1% vs. 15.6%), excoriation (26.9%/34.6% vs. 3.1%), lichenification (9.6%/13.5% vs. 1.4%) and dryness (8.6%/11.9% vs. 1.8%). Resolution rates were also higher with upadacitinib (15 mg/30 mg) vs. placebo at Week 16 (P &amp;lt; 0.0001) for erythema (22.2%/29.7% vs. 2.2%), edema/papulation (33.6%/42.8% vs. 4.9%), oozing/crusting (62.1%/72.0% vs. 20.5%), excoriation (43.3%/54.6% vs. 8.5%), lichenification (30.8%/40.7% vs. 5.2%) and dryness (28.7%/35.9% vs. 4.4%). Greater proportions of patients treated with upadacitinib 15 mg or upadacitinib 30 mg achieved resolution of erythema, edema/papulation, oozing/crusting, excoriation, lichenification or dryness compared with placebo at Week 2 and Week 16. Complete resolution of these clinical signs of AD may correspond to reductions in disease burden that translate to improved QoL. Consideration of the clinical signs of AD as assessed by the SCORAD may help inform physicians as they tailor their treatment choices specifically to the unique skin manifestations of each individual patient.

Dual-Targeted Therapy in Pediatric Inflammatory Bowel Disease: A Comprehensive Review.

Inflammatory bowel disease (IBD) is a chronic systemic immune-mediated disorder. The disease is triggered and perpetuated by a complex interplay between genetic predisposition, dysregulated immune responses, and environmental factors. Pediatric IBD is considered to be more aggressive compared with adult-onset IBD, and commonly requires more intensive pharmacological and surgical treatments. Although the use of targeted therapy, such as biologic therapy and small molecule therapy, is on the rise, there are children with IBD who are refractory to all current therapeutic options. For them, a combination of biologic agents or a biologic agent with small molecules as dual-targeted therapy (DTT) may be a possible therapeutic option. The main indications for DTT are high inflammatory burden and refractoriness to standard therapy, extra-intestinal manifestations of IBD, adverse effects of therapy, and co-existing immune-mediated inflammatory disorders. Several combination therapies were described for pediatric refractory IBD. The main ones were anti-tumor necrosis factor (TNF) agents and vedolizumab (VDZ), anti-TNF and ustekinumab (UST), VDZ and UST, and biologic agents with tofacitinib. DTT exhibits high efficacy, with high rates of clinical response and remission as well as biomarker remission. The data on endoscopic and radiologic remission are scarce. Most of the adverse effects reported under DTT were mild; however, the serious ones that had been observed mandate a profoundly cautious approach when considering it. Triple immunosuppressive therapy and combinations of biologics with emergent therapies such as selective Janus kinase inhibitors, sphingosine-1-phosphate receptor modulators, and anti-interleukin-23 agents, are potential future regimens for children with IBD who are refractory to current therapeutic options. This review provides an update of publications on these issues.

Synthesis and biological evaluation of thieno[3,2-c]pyrazol-3-amine derivatives as potent glycogen synthase kinase 3β inhibitors for Alzheimer’s disease

Glycogen synthase kinase 3β (GSK-3β) is a potential target for anti-Alzheimer’s disease (AD) drug development. In this study, a series of novel thieno[3,2-c]pyrazol-3-amine derivatives was synthesized and evaluated as potential GSK-3β inhibitors by structure-based drug design. The thieno[3,2-c]pyrazol-3-amine derivative 54 with a 4-methylpyrazole moiety which interacted with Arg141 by π-cation interaction was identified as a potent GSK-3β inhibitor with an IC50 of 3.4 nM and an acceptable kinase selectivity profile. In the rat primary cortical neurons, compound 54 showed neuroprotective effects on Aβ-induced neurotoxicity. Western blot analysis indicated that 54 inhibited GSK-3β by up-regulating the expression of phosphorylated GSK-3β at Ser9 and down-regulating the expression of phosphorylated GSK-3β at Tyr216. Meanwhile, 54 decreased tau phosphorylation at Ser396 in a dose-dependent way. In astrocytes and microglia cells, 54 inhibited the expression of inducible nitric oxide synthase (iNOS), indicating that 54 showed an anti-neuroinflammatory effect. In the AlCl3-induced zebrafish AD model, 54 significantly ameliorated the AlCl3-induced dyskinesia, demonstrating its anti-AD activity in vivo.

CDK2 regulates collapsed replication fork repair in CCNE1-amplified ovarian cancer cells via homologous recombination.

CCNE1 amplification is a common alteration in high-grade serous ovarian cancer and occurs in 15-20% of these tumors. These amplifications are mutually exclusive with homologous recombination deficiency, and, as they have intact homologous recombination, are intrinsically resistant to poly (ADP-ribose) polymerase inhibitors or chemotherapy agents. Understanding the molecular mechanisms that lead to this mutual exclusivity may reveal therapeutic vulnerabilities that could be leveraged in the clinic in this still underserved patient population. Here, we demonstrate that CCNE1-amplified high-grade serous ovarian cancer cells rely on homologous recombination to repair collapsed replication forks. Cyclin-dependent kinase 2, the canonical partner of cyclin E1, uniquely regulates homologous recombination in this genetic context, and as such cyclin-dependent kinase 2 inhibition synergizes with DNA damaging agents in vitro and in vivo. We demonstrate that combining a selective cyclin-dependent kinase 2 inhibitor with a DNA damaging agent could be a powerful tool in the clinic for high-grade serous ovarian cancer.