We report results from a phase IIa study of efficacy and safety of PF-06700841, an oral TYK2/Jak1 inhibitor, in patients with moderate-to-severe plaque psoriasis (NCT02969018).
Patients were ...randomized to PF-06700841 30 mg once daily (QD), 60 mg QD, or placebo (4-week induction), followed by 10 mg QD, 30 mg QD, 100 mg once weekly, or placebo (8-week maintenance). The primary endpoint was week 12 change from baseline in PASI score. Secondary endpoints were the proportion of patients achieving 75% and 90% reduction from baseline PASI at week 12.
In total, 212 patients in 35 sites were treated; mean (SD) baseline PASI score was 20.8 (7.68). Decreases in PASI at week 12 were statistically significant compared with placebo in five treatment groups. The greatest change from baseline (least squares mean change –17.3 95% confidence interval, –20.0 to –14.6) was observed in the 30-mg QD continuous treatment group. Overall, 136 patients experienced treatment-emergent adverse events, including six serious adverse events in five patients and 13 discontinuations in treatment groups because of adverse events. No herpes zoster cases or major adverse cardiac events including thromboembolic events occurred.
PF-06700841 was generally effective and well tolerated in patients with moderate-to-severe plaque psoriasis.
Despite multiple efficacious therapies in common between psoriasis (PS) and Ulcerative Colitis (UC), mechanisms underlying their common pathophysiology remain largely unclear. Here we sought to ...establish a link by evaluating expression differences and pathway alterations in diseased tissues. We identified two sets of differentially expressed genes (DEGs) between lesional and nonlesional tissues in meta-analyses of data collected from baseline samples in 3 UC and then 3 PS available clinical studies from Pfizer. A shared gene signature was defined by 190 DEGs common to both diseases. Commonly dysregulated pathways identified via enrichment analysis include interferon signaling, partly driven by genes IFI6, CXCL9, CXCL10 and CXCL11, which may attract chemotaxis of Th1 cells to inflammatory sites; IL-23 pathway (IL-23A, CCL20, PI3, CXCL1, LCN2); and Th17 pathway except IL-17A. Elevated expression of costimulatory molecules ICOS and CTLA4 suggests ongoing T-cell activation in both diseases. The clinical value of the shared signature is demonstrated by a gene set improvement score reflecting post-treatment molecular improvement for each disease. This is the first study using transcriptomic meta-analysis to define a tissue gene signature and pathways dysregulated in both PS and UC. These findings suggest immune mechanisms may initiate and sustain inflammation similarly in the two diseases.
Challenges in using cytokine data are limiting Coronavirus Disease 2019 (COVID-19) patient management and comparison among different disease contexts. We suggest mitigation strategies to improve the ...accuracy of cytokine data, as we learn from experience gained during the COVID-19 pandemic.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Selective inhibition of tyrosine kinase 2 (TYK2) may offer therapeutic promise in inflammatory conditions, with its role in downstream pro‐inflammatory cytokine signaling. In this first‐in‐human ...study, we evaluated the safety, tolerability, and pharmacokinetics (PK) of a novel TYK2 inhibitor, PF‐06826647, in healthy participants. This phase I, randomized, double‐blind, placebo‐controlled, parallel‐group study included two treatment periods (single ascending dose (SAD) and multiple ascending dose (MAD)) in healthy participants and a cohort of healthy Japanese participants receiving 400 mg q.d. or placebo in the MAD period (NCT03210961). Participants were randomly assigned to PF‐06826647 or placebo (3:1). Participants received a single oral study drug dose of 3, 10, 30, 100, 200, 400, or 1,600 mg (SAD period), then 30, 100, 400, or 1,200 mg q.d. or 200 mg b.i.d. for 10 days (MAD period). Safety (adverse events (AEs), vital signs, and clinical laboratory parameters), tolerability, and PK were assessed. Overall, 69 participants were randomized to treatment, including six Japanese participants. No deaths, serious AEs, severe AEs, or AEs leading to dose reduction or temporary/permanent discontinuation were observed. All AEs were mild in severity. No clinically relevant laboratory abnormalities or changes in vital signs were detected. PF‐06826647 was rapidly absorbed with a median time to maximum plasma concentration of 2 hours in a fasted state, with modest accumulation (< 1.5‐fold) after multiple dosing and low urinary recovery. PF‐06826647 was well‐tolerated, with an acceptable safety profile for doses up to 1,200 mg q.d. for 10 days, supporting further testing in patients.
Protein biosynthesis and extracellular secretion are essential biological processes for therapeutic protein production in mammalian cells, which offer the capacity for correct folding and proper ...post-translational modifications. In this study, we have generated bispecific therapeutic fusion proteins in mammalian cells by combining a peptide and an antibody into a single open reading frame. A neutralizing peptide directed against interleukin-17A (IL17A) was genetically fused to the N termini of an anti-IL22 antibody, through either the light chain, the heavy chain, or both chains. Although the resulting fusion proteins bound and inhibited IL22 with the same affinity and potency as the unmodified anti-IL22 antibody, the peptide modality in the fusion scaffold was not active in the cell-based assay due to the N-terminal degradation. When a glutamine residue was introduced at the N terminus, which can be cyclized to form pyroglutamate in mammalian cells, the IL17A neutralization activity of the fusion protein was restored. Interestingly, the mass spectroscopic analysis of the purified fusion protein revealed an unexpected O-linked glycosylation modification at threonine 5 of the anti-IL17A peptide. The subsequent removal of this post-translational modification by site-directed mutagenesis drastically enhanced the IL17A binding affinity and neutralization potency for the resulting fusion protein. These results provide direct experimental evidence that post-translational modifications during protein biosynthesis along secretory pathways play critical roles in determining the structure and function of therapeutic proteins produced by mammalian cells. The newly engineered peptide-antibody genetic fusion is promising for therapeutically targeting multiple antigens in a single antibody-like molecule.
Background: Protein biosynthesis and secretion are essential biological processes for therapeutic protein production.
Results: Generating functional anti-IL17A and anti-IL22 peptide-antibody bispecific therapeutic proteins requires pyroglutamate addition and O-linked glycan removal.
Conclusion: Post-translational modifications play critical roles in determining structure and function of therapeutic proteins.
Significance: The peptide-antibody genetic fusion is promising for targeting multiple antigens in a single antibody-like molecule.
The safety, tolerability, pharmacokinetics, and pharmacodynamics of PF‐06700841 were assessed in a randomized, double‐blind, placebo‐controlled, single‐ and multiple‐dose escalation, parallel‐group ...study in healthy subjects and patients with plaque psoriasis. The single ascending dose (1, 3, 10, 30, 100, or 200 mg) and multiple ascending dose (MAD; PF‐06700841; up to 175 mg once daily or 50 mg twice daily for 10 days) periods included 54 healthy participants. In addition, 30 patients with psoriasis received PF‐06700841 30 or 100 mg or placebo once daily for 28 days. Single PF‐06700841 doses were rapidly absorbed, with peak plasma concentrations ≤ 1 hour, proportional exposure up to 100 mg, and mean half‐life 3.8–7.5 hours. On day 10 of MAD, plasma concentrations peaked at ≤1.5 hours postdose (10–175 mg once daily). Elimination half‐life was 4.9–10.7 hours; steady state was reached by day 8. In psoriasis patients on day 28, peak plasma concentrations occurred at 1–2 hours. Biomarkers IP‐10 and high‐sensitivity C‐reactive protein were reduced and returned to near baseline levels after dosing. Maximal mean percent change from baseline in the Psoriasis Area and Severity Index scores for PF‐06700841 30 mg once daily and 100 mg once daily were −67.92% and −96.31%, respectively, in week 4. All adverse events were mild/moderate. PF‐06700841 was safe and well tolerated up to 200 mg once daily in healthy subjects and 100 mg once daily in patients with psoriasis, suggesting potential therapeutic utility in plaque psoriasis and other inflammatory diseases.
The IL-23/T helper type 17 cell axis is a target for psoriasis. The TYK2/Janus kinase 1 inhibitor PF-06700841 will directly suppress TYK2-dependent IL-12 and IL-23 signaling and Janus kinase ...1–dependent signaling in cells expressing these signaling molecules, including T cells and keratinocytes. This clinical study sought to define the inflammatory gene and cellular pathways through which PF-06700841 improves the clinical manifestations of psoriasis. Patients (n = 30) with moderate-to-severe psoriasis were randomized to once-daily 30 mg (n = 14) or 100 mg (n = 7) PF-06700841 or placebo (n = 9) for 28 days. Biopsies were taken from nonlesional and lesional skin at baseline and weeks 2 and 4. Changes in the psoriasis transcriptome and genes induced by IL-17 in keratinocytes were evaluated with microarray profiling and reverse transcriptase–PCR. Reductions in IL-17A, IL-17F, and IL-12B mRNA were observed as early as 2 weeks and approximately 70% normalization of lesional gene expression after 4 weeks. Immunohistochemistry showed significant decreases in markers of keratinocyte activation, epidermal thickness, KRT16 and Ki-67 expression, and immune cell infiltrates CD3+/CD8+ (T cells) and CD11c (dendritic cells) after 2 weeks of treatment, corresponding with improvement in histologic score. PF-06700841 improves clinical symptoms of chronic plaque psoriasis by inhibition of proinflammatory cytokines that require TYK2 and Janus kinase 1 for signal transduction.
Aims
To determine the safety, tolerability, pharmacokinetics and pharmacodynamics of the Janus kinase 1‐selective inhibitor, PF‐04965842.
Methods
This was a phase 1, first‐in‐human, randomized, ...double‐blind, placebo‐controlled, combination single‐ and multiple‐dose escalation, parallel design study in healthy subjects (http://clinicaltrials.gov, NCT01835197). Subjects received a single dose of placebo or 3, 10, 30, 100, 200, 400 or 800 mg PF‐04965842 (single ascending dose phase) and placebo or 30 mg once daily (QD), 100 mg QD, 200 mg QD, 400 mg QD, 100 mg twice daily (BID) or 200 mg BID PF‐04965842 for 10 consecutive days (multiple ascending dose phase). The primary objective was to determine the safety and tolerability of PF‐04965842.
Results
Seventy‐nine subjects were randomized and received study treatments. There were no deaths or serious adverse events. The most frequent treatment‐emergent adverse events were headache (n = 13), diarrhoea (n = 11) and nausea (n = 11). PF‐04965842 was absorbed rapidly (median time at which maximum plasma concentration occurred generally ≤1 h following either single‐ or multiple‐dose administration) and eliminated rapidly (mean t½ 2.8−5.2 h after 10 days of QD or BID administration in the multiple ascending dose phase). Increases in maximum plasma concentration and area under the concentration–time curve were dose proportional up to 200 mg (single or total daily doses) with an apparent trend towards greater than proportional increases with higher doses. Less than 4.4% of the dose was recovered unchanged in urine. Changes in pharmacodynamic biomarkers were consistent with the known effects of Janus kinase signalling inhibition.
Conclusions
These results support further evaluation of PF‐04965842 for clinical use in patients with inflammatory diseases.
Ritlecitinib is a small molecule in clinical development that covalently and irreversibly inhibits Janus kinase 3 (JAK3) and the TEC family of kinases (BTK, BMX, ITK, TXK, and TEC). This phase 1, ...open-label, parallel-group study assessed target occupancy and functional effects of ritlecitinib on JAK3 and TEC family kinases in healthy participants aged 18-60 years who received 50 or 200 mg single doses of ritlecitinib on day 1. Blood samples to assess ritlecitinib pharmacokinetics, target occupancy, and pharmacodynamics were collected over 48 hours. Target occupancy was assessed using mass spectroscopy. Functional inhibition of JAK3-dependent signaling was measured by the inhibition of the phosphorylation of its downstream target signal transducer and activator of transcription 5 (pSTAT5), following activation by interleukin 15 (IL-15). The functional inhibition of Bruton's tyrosine kinase (BTK)-dependent signaling was measured by the reduction in the upregulation of cluster of differentiation 69 (CD69), an early marker of B-cell activation, following treatment with anti-immunoglobulin D. Eight participants received one 50 mg ritlecitinib dose and 8 participants received one 200 mg dose. Ritlecitinib plasma exposure increased in an approximately dose-proportional manner from 50 to 200 mg. The maximal median JAK3 target occupancy was 72% for 50 mg and 64% for 200 mg. Ritlecitinib 50 mg had >94% maximal target occupancy of all TEC kinases, except BMX (87%), and 200 mg had >97% for all TEC kinases. For BTK and TEC, ritlecitinib maintained high target occupancy throughout a period of 48 hours. Ritlecitinib reduced pSTAT5 levels following IL-15- and BTK-dependent signaling in a dose-dependent manner. These target occupancy and functional assays demonstrate the dual inhibition of the JAK3- and BTK-dependent pathways by ritlecitinib. Further studies are needed to understand the contribution to clinical effects of inhibiting these pathways.
Background Inducible costimulator (ICOS) and its ligand (ICOSL) are a pair of costimulatory molecules that co-localize in germinal centers (GC). This interaction is critical for the maturation of GC ...B cells to affinity-matured memory B cells and long-lived plasma cells. Both ICOS and ICOSL are implicated in systemic lupus erythematosus (SLE). It is known that ICOSL sheds from the cell membrane and that the soluble form of ICOSL (sICOSL) is elevated in SLE; though the function of sICOSL is poorly understood. While it is known that binding of ICOSL on antigen-presenting cells (APC) to ICOS on T cells leads to cell signaling resulting in T cell activation and differentiation, there is also some preliminary evidence that reverse signaling may also occur through ICOSL in APCs. The binding interaction between ICOS and sICOSL has not been fully characterized and is important to understand if either molecule is to be targeted therapeutically. The hypothesis evaluated in this study was that the ICOS: ICOSL interaction is a potent and critical mediator of proinflammatory signaling and immune activation that functions both via activated T cell-mediated forward signaling and APC-mediated reverse signaling mechanisms and that ectodomain shedding of ICOSL is a protective mechanism that leads to down-regulation of the proinflammatorysignaling cascade initiated by this interaction. The aim of this thesis is to characterize the binding interaction between ICOS and ICOSL and to provide a review of the literature and discuss future work that would enhance the biological understanding of this interaction and its role in lupus and other autoimmune diseases. Methods The binding interaction between ICOS and ICOSL was characterized using both soluble proteins and cells with expressed recombinant proteins. Purified soluble ICOSL (sICOSL) was characterized using size-exclusion chromatography multiangle light scattering (SEC-MALS). Surface plasmon resonance (SPR) was used to measure the binding affinity between sICOSL and human ICOS fused to the fragment crystallizable (Fc) portion of an immunoglobulin molecule (hICOS.Fc). The binding interaction was further characterized to account for avidity between hICOS.Fc and sICOSL and between hICOS.Fc and ICOSL expressed recombinant on the cell surface using a solution-based binding method. Results Expressed recombinant and purified sICOSL dimerized over time and with increasing temperatures. The sICOSL: hICOS.Fc interaction did not follow a typical 1:1 binding interaction. In-solution binding experiments resulted in a tighter equilibrium dissociation binding constant (KD) than the surface-based results obtained by SPR. The KD for hICOS.Fc binding to human ICOSL(hICOSL) expressed on cells agreed well with the KD for hICOS.Fc to the soluble protein, indicating that the in-solution binding measurement may measure binding avidity rather than affinity and that this may be the more physiologically relevant interaction. Conclusions I show in the experimental part of this study that the interaction between ICOS and ICOSL is quite potent and that much of the binding strength is due to avidity, or the combined strength of multiple parts of the molecules interacting with one another, rather than the affinity alone. As this interaction is implicated in SLE pathogenesis, it would be useful to develop a clearer understanding of the most relevant physiological form of these molecules (soluble or transmembrane) and of the biological signaling events that are initiated via this interaction in order to determine whether targeting ICOS or ICOSL may be therapeutically viable approaches.
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