Real-World Incidence and Determinants of Infection in Patients With Rheumatoid Arthritis Treated With Golimumab After a Median Follow-Up Time of 27 Months

OBJECTIVE

To characterize the long-term incidence of infection in patients with rheumatoid arthritis (RA) treated with subcutaneous golimumab (GOL) in Canadian routine care, assess the effect of infections on GOL retention, and explore factors associated with infection incidence.

METHODS

Patients with RA enrolled in the Biologic Treatment Registry Across Canada (BioTRAC) initiating GOL treatment were included. The incidence density rates (IDRs) of total infection (TI), serious infection (SI), and nonserious infection (NSI) were calculated for the overall follow-up (90 months) and by 6-month intervals. Determinants of infection over time or within the first 6 months were explored using generalized estimating equation models and logistic regression, respectively.

RESULTS

Five hundred thirty patients were included; mean baseline age was 57.7 years and RA duration was 8.0 years. Over an average follow-up of 27.0 months, the IDR for TIs was 35.1 events per 100 person-years (PYs), the majority occurring during the first 6 months; IDRs for NSIs and SIs were 32.9 and 2.2 events per 100 PYs, respectively. No predictors were identified for infection incidence within 6 months. Comorbid pulmonary disease was associated with significantly higher odds of TIs and NSIs over time, whereas higher age and high corticosteroid (CS) dose (> 5 mg/day) predicted higher odds of SIs. Incidence of SIs, but not NSIs, was associated with significantly higher odds of GOL discontinuation.

CONCLUSION

Long-term GOL treatment was associated with relatively low infection rates, most being nonserious and occurring during the first 6 months. Pulmonary disease, higher age, and high CS dose were identified as significant predictors of infections. SIs, but not NSIs, predicted higher odds of GOL discontinuation. (ClinicalTrials.gov: NCT00741793).

Safety of Guselkumab With and Without Prior Tumor Necrosis Factor Inhibitor Treatment: Pooled Results Across 4 Studies in Patients With Psoriatic Arthritis

OBJECTIVE

Assess pooled safety results through the end of the phase II/III studies of guselkumab (GUS; ≤ 2 years) in tumor necrosis factor inhibitor (TNFi)-naïve and -experienced patients with psoriatic arthritis (PsA).

METHODS

Data were pooled from the Phase 2 and DISCOVER-1 (both TNFi-naïve and -experienced), DISCOVER-2 (TNFi-naïve), and COSMOS (TNFi-experienced) studies. Patients with active PsA were randomized to GUS 100 mg every 4 or 8 weeks (Q4W + Q8W = Combined GUS) or placebo (PBO) with crossover to GUS Q4W or Q8W at week 24. Time-adjusted adverse event (AE) rates (events/100 patient-years [PY]) and clinical laboratory findings were assessed during the PBO-controlled period and through end of study (≤ 2 years).

RESULTS

Of 1554 randomized patients (n = 373 [GUS Q4W], 664 [GUS Q8W], and 517 [PBO]), 1138 (73.23%) were TNFi-naïve and 416 (26.77%) were TNFi-experienced. Respective AE rates through week 24 were 220.8/100 PY (TNFi-naïve) and 251.6/100 PY (TNFi-experienced) in the Combined GUS group and 196.1/100 PY (TNFi-naïve) and 303.0/100 PY (TNFi-experienced) in the PBO group. Among all GUS-treated patients (including those who crossed over from PBO), low AE rates were maintained during long-term evaluation in both TNFi-naïve (139.7/100 PY) and TNFi-experienced (174.0/100 PY) patients. Rates/100 PY of AEs leading to treatment discontinuation, serious AEs, and other AEs of interest, as well as occurrence of elevated hepatic transaminase levels and decreased neutrophil counts were consistent between PBO and GUS-treated patients through week 24 regardless of prior TNFi use and remained low through the end of the studies.

CONCLUSION

The safety profile of GUS in TNFi-experienced patients was consistent with that in TNFi-naïve patients, which remained favorable for up to 2 years. [ClinicalTrials.gov: Phase 2 (NCT02319759), DISCOVER-1 (NCT03162796), DISCOVER-2 (NCT03158285), and COSMOS (NCT03796858)].

Patterns and predictors of long-term retention of inflammatory bowel or rheumatoid disease patients on innovator infliximab: an analysis of a Canadian prescriptions claims database

BACKGROUND

Long-term effectiveness is an important factor when considering treatment decisions.

OBJECTIVE

To determine the long-term retention patterns of Canadian inflammatory bowel disease (IBD) and rheumatologic disease (RD) patients, including rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis, treated with innovator infliximab (IFX) and to assess the impact of year-over-year cumulative IFX exposure on retention in both patient populations.

PATIENTS AND METHODS

This analysis used a Canadian longitudinal prescription claims database to measure retention on IFX over a period of 5 years. Twelve-month unadjusted odds ratios of retention by time on IFX were calculated for the overall cohort, and within-group comparisons evaluated differences according to age, sex, region, insurance coverage, use of concomitant immunosuppressant therapy, indication (RD cohort only), and previous biologic experience. Between-group analyses compared unadjusted 5-year retention among the same variables. Variables that were independently associated with longer retention on IFX were identified using multivariable regression.

RESULTS

Seven thousand eight hundred and six IBD patients and 2,935 RD patients on stable treatment with IFX were included in the analysis. Sixty-nine percent of IBD patients and 66% of RD patients were retained on IFX after 1 year and 33% and 29%, respectively, were retained after 5 years. Moreover, the probability of being retained on IFX significantly increased with cumulative time on IFX. Independent predictors of 5-year retention included sex, region, and type of insurance coverage among IBD patients and region, type of insurance, prior biologic therapy, and specific indication among RD patients. Patients with IBD were 17% more likely to be retained on IFX over 5 years compared to patients with RD.

CONCLUSION

Real-world Canadian IBD and RD patients on IFX have good overall long-term treatment retention. Previous duration of IFX treatment predicts better future retention, and this knowledge could help inform treatment decisions when patients have been stable on IFX treatment for varying periods of time.

Proinflammatory gene induction by platelet-activating factor mediated via its cognate nuclear receptor

It has been postulated that intracellular binding sites for platelet-activating factor (PAF) contribute to proinflammatory responses to PAF. Isolated nuclei from porcine cerebral microvascular endothelial cells (PCECs) produced PAF-molecular species in response to H(2)O(2). Using FACS analysis, we demonstrated the expression of PAF receptors on cell and nuclear surfaces of PCECs. Confocal microscopy studies performed on PCECs, Chinese hamster ovary cells stably overexpressing PAF receptors, and isolated nuclei from PCECs also showed a robust nuclear distribution of PAF receptors. Presence of PAF receptors at the cell nucleus was further revealed in brain endothelial cells by radioligand binding experiments, immunoblotting, and in situ in brain by immunoelectron microscopy. Stimulation of nuclei with methylcarbamate-PAF evoked a decrease in cAMP production and a pertussis toxin-sensitive rise in nuclear calcium, unlike observations in plasma membrane, which exhibited a pertussis toxin-insensitive elevation in inositol phosphates. Moreover, on isolated nuclei methylcarbamate-PAF evoked the expression of proinflammatory genes inducible nitric oxide synthase and cyclooxygenase-2 (COX-2) and was associated with augmented extracellular signal-regulated kinase 1/2 phosphorylation and NF-kappaB binding to the DNA consensus sequence. COX-2 expression was prevented by mitogen-activated protein kinase kinase/extracellular signal-regulated kinase 1/2 and NF-kappaB inhibitors. This study describes for the first time the nucleus as a putative organelle capable of generating PAF and expresses its receptor, which upon stimulation induces the expression of the proinflammatory gene COX-2.

Building Canada's health research capacity within the framework of the Canadian Institutes of Health Research

The establishment of the Canadian Institutes of Health Research (CIHR) generated considerable excitement about the capacity for health research in Canada. The long term success of the CIHR will be determined, in part, by its ability to recruit, train and retain a cadre of talented researchers. During a workshop to develop the research agenda for one of the proposed institutes within the CIHR, a national, multidisciplinary group of clinical and basic science research trainees were invited to present their views about the challenges that face Canadian researchers of tomorrow. The objective of this paper is to present the challenges associated with recruiting, training and retaining health researchers, and to identify new opportunities provided by the creation of the CIHR. The present paper concludes with suggestions that may improve the success of researchers and, ultimately, the success of the CIHR.

Role of thromboxane in retinal microvascular degeneration in oxygen-induced retinopathy

Microvascular degeneration is an important event in oxygen-induced retinopathy (OIR), a model of retinopathy of prematurity. Because oxidant stress abundantly generates thromboxane A2 (TxA2), we tested whether TxA2 plays a role in retinal vasoobliteration of OIR and contributes to such vascular degeneration by direct endothelial cytotoxicity. Hyperoxia-induced retinal vasoobliteration in rat pups (80% O2 exposure from postnatal days 5-14) was associated with increased TxB2 generation and was significantly prevented by TxA2 synthase inhibitor CGS-12970 (10 mg x kg(-1) x day(-1)) or TxA2-receptor antagonist CGS-22652 (10 mg x kg(-1) x day(-1)). TxA2 mimetics U-46619 (EC50 50 nM) and I-BOP (EC50 5 nM) caused a time- and concentration-dependent cell death of neuroretinovascular endothelial cells from rats as well as newborn pigs but not of smooth muscle and astroglial cells; other prostanoids did not cause cell death. The peroxidation product 8-iso-PGF2, which is generated in OIR, stimulated TxA2 formation by endothelial cells and triggered cell death; these effects were markedly diminished by CGS-12970. TxA2-dependent neuroretinovascular endothelial cell death was mostly by necrosis and to a lesser extent by apoptosis. The data identify an important role for TxA2 in vasoobliteration of OIR and unveil a so far unknown function for TxA2 in directly triggering neuroretinal microvascular endothelial cell death. These effects of TxA2 might participate in other ischemic neurovascular injuries.

Prolonged hypercapnia-evoked cerebral hyperemia via K(+) channel- and prostaglandin E(2)-dependent endothelial nitric oxide synthase induction

Mechanisms for secondary sustained increase in cerebral blood flow (CBF) during prolonged hypercapnia are unknown. We show that induction of endothelial NO synthase (eNOS) by an increase in prostaglandins (PGs) contributes to the secondary CBF increase during hypercapnic acidosis. Ventilation of pigs with 6% CO(2) (PaCO(2 approximately)65 mm Hg; pH approximately 7.2) caused a approximately 2.5-fold increase in CBF at 30 minutes, which declined to basal values at 3 hours and gradually rose again at 6 and 8 hours; the latter increase was associated with PG elevation, nitrite formation, eNOS mRNA expression, and in situ NO synthase (NOS) reactivity (NADPH-diaphorase staining). Subjecting free-floating brain sections to acidotic conditions increased eNOS expression, the time course of which was similar to that of CBF increase. Treatment of pigs with the cyclooxygenase inhibitor diclofenac or the NOS inhibitor Nomega-nitro-L-arginine blunted the initial rise and prevented the secondary CBF increase during hypercapnic acidosis; neuronal NOS blockers 1-(2-trifluoromethylphenyl) imidazole and 3-bromo-7-nitroindazole were ineffective. Diclofenac abolished the hypercapnia-induced rise in cerebrovascular nitrite production, eNOS mRNA expression, and NADPH-diaphorase reactivity. Acidosis (pH approximately 7.15, PCO(2 approximately )40 mm Hg; 6 hours) produced similar increases in prostaglandin E(2) (PGE(2)) and eNOS mRNA levels in isolated brain microvessels and in NADPH-diaphorase reactivity of brain microvasculature; these changes were prevented by diclofenac, by the receptor-operated Ca(2+) channel blocker SK&F96365, and by the K(ATP) channel blocker glybenclamide. Acidosis increased Ca(2+) transients in brain endothelial cells, which were blocked by glybenclamide and SK&F96365 but not by diclofenac. Increased PG-related eNOS mRNA and NO-dependent vasorelaxation to substance P was detected as well in rat brain exposed to 6 hours of hypercapnia. PGE(2) was the only major prostanoid that modulated brain eNOS expression during acidosis. Thus, in prolonged hypercapnic acidosis, the secondary CBF rise is closely associated with induction of eNOS expression; this seems to be mediated by PGE(2) generated by a K(ATP) and Ca(2+) channel-dependent process.

Augmented vasoconstriction and thromboxane formation by 15-F(2t)-isoprostane (8-iso-prostaglandin F(2alpha)) in immature pig periventricular brain microvessels

BACKGROUND AND PURPOSE

Oxidant stress, especially in the premature, plays a major role in the pathogenesis of hypoxic-ischemic encephalopathies mostly manifested in the periventricular region. We studied the vasomotor mode of actions of the peroxidation product 15-F(2t)-isoprostane (15-F(2t)-IsoP) (8-iso-prostaglandin F(2alpha)) on periventricular region during development.

METHODS

Effects of 15-F(2t)-IsoP on periventricular microvessels of fetal, newborn, and juvenile pigs were studied by video imaging and digital analysis techniques. Thromboxane formation and intracellular Ca(2+) were measured by radioimmunoassay and by using the fluorescent indicator fura 2-AM.

RESULTS

15-F(2t)-IsoP-mediated constriction of periventricular microvessels decreased as a function of age such that in the fetus it was approximately 2.5-fold greater than in juvenile pigs. 15-F(2t)-IsoP evoked more thromboxane formation in the fetus than in the newborn, which was greater than that in the juvenile periventricular region; this was associated with immunoreactive thromboxane A(2) (TXA(2)) synthase expression in the fetus that was greater than that in newborn pigs, which was greater than that in juvenile pigs. 15-F(2t)-IsoP-induced vasoconstriction was markedly inhibited by TXA(2) synthase and receptor blockers (CGS12970 and L670596). Vasoconstrictor effects of the TXA(2) mimetic U46619 on fetal, neonatal, and juvenile periventricular microvessels did not differ. 15-F(2t)-IsoP increased TXA(2) synthesis by activating Ca(2+) influx through non-voltage-gated channels in endothelial cells (SK&F96365 sensitive) and N-type voltage-gated channels (omega-conotoxin sensitive) in astrocytes; smooth muscle cells were not responsive to 15-F(2t)-IsoP but generated Ca(2+) transients to U46619 via L-type voltage-sensitive channels.

CONCLUSIONS

15-F(2t)-IsoP causes periventricular brain region vasoconstriction in the fetus that is greater than that in the newborn, which in turn is greater than that in the juvenile due to greater TXA(2) formation generated through distinct stimulatory pathways, including from endothelial and astroglial cells. The resulting hemodynamic compromise may contribute to the increased vulnerability of the periventricular brain areas to oxidant stress-induced injury in immature subjects.