Long-term efficacy and safety of guselkumab, a monoclonal antibody specific to the p19 subunit of interleukin-23, through two years: results from a phase III, randomized, double-blind, placebo-controlled study conducted in biologic-naive patients with active Psoriatic Arthritis

Objective To assess long-term efficacy and safety of guselkumab, an interleukin-23 p19 subunit (IL-23p19) inhibitor, in patients with active psoriatic arthritis (PsA) from the phase III DISCOVER-2 trial. Methods In the DISCOVER-2 trial, patients with active PsA (>= 5 swollen joints and >= 5 tender joints; C-reactive protein level >= 0.6 mg/dl) despite prior nonbiologic therapy were randomized to receive the following: guselkumab 100 mg every 4 weeks; guselkumab 100 mg at weeks 0 and 4 and then every 8 weeks; or placebo with crossover to guselkumab 100 mg every 4 weeks, beginning at week 24. Efficacy assessments included American College of Rheumatology >= 20%/50%/70% improvement criteria (ACR20/50/70), Investigator's Global Assessment (IGA) of psoriasis score of 0 (indicating complete skin clearance), resolution of enthesitis (Leeds Enthesitis Index) and dactylitis (Dactylitis Severity Score), and changes in the Sharp/van der Heijde modified radiographic scores for PsA. Clinical data (imputed as no response/no change from baseline if missing) and observed radiographic data were summarized through week 100; safety assessments continued through week 112. Results Of the 739 randomized and treated patients, 652 (88%) completed treatment through week 100. Across groups of guselkumab-treated patients (including those in the placebo-guselkumab crossover group), the following findings at week 100 indicated that amelioration of arthritis signs/symptoms and extraarticular manifestations was durable through 2 years: ACR20 response (68-76%), ACR50 response (48-56%), ACR70 response (30-36%), IGA score of 0 (55-67%), enthesitis resolution (62-70%), and dactylitis resolution (72-83%). Mean changes in the Sharp/van der Heijde modified score for PsA from weeks 52 to week 100 (range 0.13-0.75) indicated that the low rates of radiographic progression observed among guselkumab-treated patients at earlier time points extended through week 100. Through week 112, 8% (5.8 per 100 patient-years) and 3% (1.9 per 100 patient-years) of the 731 guselkumab-treated patients had a serious adverse event or serious infection, respectively; 1 death occurred (road traffic accident). Conclusion In biologic-naive PsA patients, guselkumab provided durable improvements in multiple disease domains with no unexpected safety findings through 2 years.Pathophysiology and treatment of rheumatic disease

Mathematics of Gravitational Lensing: Multiple Imaging and Magnification

The mathematical theory of gravitational lensing has revealed many generic and global properties. Beginning with multiple imaging, we review Morse-theoretic image counting formulas and lower bound results, and complex-algebraic upper bounds in the case of single and multiple lens planes. We discuss recent advances in the mathematics of stochastic lensing, discussing a general formula for the global expected number of minimum lensed images as well as asymptotic formulas for the probability densities of the microlensing random time delay functions, random lensing maps, and random shear, and an asymptotic expression for the global expected number of micro-minima. Multiple imaging in optical geometry and a spacetime setting are treated. We review global magnification relation results for model-dependent scenarios and cover recent developments on universal local magnification relations for higher order caustics.Comment: 25 pages, 4 figures. Invited review submitted for special issue of General Relativity and Gravitatio

Guselkumab in biologic-naïve patients with active psoriatic arthritis (DISCOVER-2): a double-blind, randomised, placebo-controlled phase 3 trial

Background The interleukin-23 (IL-23)/T-helper 17 cell pathway is implicated in psoriatic arthritis pathogenesis. Guselkumab, an IL-23 inhibitor that specifically binds the IL-23 p19 subunit, significantly and safely improved psoriatic arthritis in a phase 2 study. DISCOVER-2 was a phase 3 trial to assess guselkumab in biologic-naive patients with psoriatic arthritis.Methods This phase 3, double-blind, placebo-controlled study was done at 118 sites in 13 countries across Asia, Europe, and North America. We enrolled biologic-naive patients with active psoriatic arthritis (at least five swollen joints, at least five tender joints, and C-reactive protein =0.6 mg/dL) despite standard therapies. Patients were randomly assigned (1:1:1, computer-generated permuted blocks; stratified by baseline disease-modifying antirheumatic drug use and C-reactive protein concentration) to subcutaneous injections of guselkumab 100 mg every 4 weeks; guselkumab 100 mg at weeks 0, 4, then every 8 weeks; or placebo. The primary endpoint was American College of Rheumatology 20% improvement (ACR20) response at week 24 in all patients per assigned treatment group. Safety was assessed in all patients per treatment received. This trial is registered at ClinicalTrials.gov, NCT03158285 (active, not recruiting).Findings From July 13, 2017, to Aug 3, 2018, 1153 patients were screened, of whom 741 were randomly assigned to receive guselkumab every 4 weeks (n=246), every 8 weeks (n=248), or placebo (n=247). One patient in the every 4 weeks group and one in the placebo group did not start treatment, and the remaining 739 patients started treatment; 716 patients continued treatment up to week 24. Significantly greater proportions of patients in the guselkumab every 4 weeks group (156 [64%] of 245 [95% CI 57-70]) and every 8 weeks group (159 [64%] of 248 [58-70]) than in the placebo group ( 81 [33%] of 246 [27-39]) achieved an ACR20 response at week 24 (percentage differences vs placebo 31% [95% CI 22-39] for the every 4 weeks group and 31% [23-40] for the every 8 weeks group; both p<0.0001). Up to week 24, serious adverse events occurred in eight (3%) of 245 patients receiving guselkumab every 4 weeks (three serious infections), three (1%) of 248 receiving guselkumab every 8 weeks (one serious infection), and seven (3%) of 246 receiving placebo (one serious infection). No deaths occurred.Interpretation Guselkumab, a human monoclonal antibody that specifically inhibits IL-23 by binding the cytokine's p19 subunit, was efficacious and demonstrated an acceptable benefit-risk profile in patients with active psoriatic arthritis who were naive to treatment with biologics. These data support the use of selective inhibition of IL-23 to treat psoriatic arthritis

Apoptotic cell death makes a minor contribution to reperfusion injury in skeletal muscle in the rat

Objective: to determine if apoptotic cell death contributes to skeletal muscle reperfusion injury. Methods: leg ischaemia was induced in rats with a tourniquet and maintained for 4 h before reperfusion for 24 or 72 h. Apoptosis was assessed by morphology, in situ end labelling of DNA fragments, DNA laddering, expression of p53 mRNA and detection of caspase-3-like proteolytic activity. Results: increased caspase-3-like activity was detected in muscle following ischaemia and zero, 24 h or 72 h of reperfusion. Levels remained relatively low but with a highly significant difference in enzyme activity between the ischaemic and non-ischaemic legs (p <0.0001, Repeated Measures Analysis of Variance). Morphological examination showed considerable oedema, disruption of muscle fibres and infiltration of white cells into tissues. Muscle nuclei did not show any morphological evidence of apoptosis and were negative for DNA fragmentation, while occasional neutrophils contained fragmented DNA. Expression of p53 was not induced by ischaemia and reperfusion and DNA ladders were not detected. Conclusions: the cells undergoing apoptosis were infiltrating neutrophils rather than muscle cells and reperfused muscle was damaged largely by an inflammatory process involving considerable oedema.P.A. Cowled, L. Leonardos, S.H. Millard and R.A. Fitridg