Abstract
Objective
To investigate the long-term efficacy and safety of the IL-6 receptor antibody tocilizumab in patients with Takayasu arteritis (TAK).
Methods
Patients completing the randomized, ...double-blind, placebo-controlled period of the TAKT (Takayasu arteritis Treated with Tocilizumab) trial were followed up during open-label extended treatment with weekly s.c. tocilizumab 162 mg for up to 96 weeks or longer, with oral glucocorticoid tapering performed at the investigators’ discretion. Endpoints of the extension analysis included steroid-sparing effects of tocilizumab, imaging data, patient-reported outcomes (36-Item Short Form Health Survey) and safety.
Results
All 36 patients enrolled in the double-blind period entered the open-label extension; 28 patients received tocilizumab for 96 weeks. The median glucocorticoid dose was 0.223 mg/kg/day at the time of relapse before study entry, 0.131 mg/kg/day (interquartile range 0.099, 0.207) after 48 weeks and 0.105 mg/kg/day (interquartile range 0.039, 0.153) after 96 weeks. Overall, 46.4% of patients reduced their dose to <0.1 mg/kg/day, which was less than half the dose administered at relapse before study entry (mean difference –0.120 mg/kg/day; 95% CI −0.154, −0.087). Imaging evaluations indicated that most patients’ disease was improved (17.9%) or stable (67.9%) after 96 weeks compared with baseline. Mean 36-Item Short Form Health Survey physical and mental component summary scores and 7 of 8 domain scores were clinically improved from baseline and maintained over 96 weeks of tocilizumab treatment. No unexpected safety issues were reported.
Conclusion
These results in patients with Takayasu arteritis provide evidence of a steroid-sparing effect and improvements in well-being during long-term treatment with once-weekly tocilizumab 162 mg, with no new safety concerns.
Trial registration
JAPIC Clinical Trials Information, http://www.clinicaltrials.jp/user/cteSearch_e.jsp, JapicCTI-142616.
We present safety and efficacy data from Japanese clinical studies on monotherapy with tocilizumab (TCZ), a humanized anti-interleukin 6 receptor monoclonal antibody, in which 601 patients with ...moderate to severe rheumatoid arthritis, with a total of 2188 patient-years (pt-yr) exposure, were enrolled. The median treatment duration was 3.8 years. The incidence of adverse events (AEs), including abnormal laboratory test results, was calculated as 465.1 per 100 pt-yr. The most common serious adverse events (SAEs) were infections (6.22 per 100 pt-yr). There was no increase in the frequency of AEs or SAEs with long-term treatment. Abnormalities in the laboratory test results, such as increases in lipid parameters or abnormal liver function parameters, were common, but most were mild and there were no SAEs related to them. At baseline, 546 patients (90.8%) were taking corticosteroids; of these, 77.8% were able to decrease their corticosteroid dose during the study period, while 35.2% discontinued corticosteroids altogether. In the patients treated longer than 5 years, 91.3, 73.0, and 51.3% met the ACR20, ACR50, and ACR70 response criteria, respectively, and 59.7% met the DAS remission criterion (DAS28 <2.6) at 5 years. In conclusion, based on these results, TCZ has shown good tolerability and high efficacy during long-term treatment.
Interleukin-6 (IL-6) is a multifunctional cytokine that regulates immune response and induces acute phase response. Despite the important physiological activities of IL-6, dysregulated overproduction ...of IL-6 is pathologically involved in various immune-mediated inflammatory diseases (IMIDs) including rheumatoid arthritis (RA). A series of clinical studies of tocilizumab, a humanized anti-IL-6 receptor (IL-6R) antibody, for patients with RA refractory to conventional therapy or anti-tumor necrosis factor therapy have demonstrated the clinical benefit of IL-6 blockade in RA. On the other hand, there is now accumulating evidence that tocilizumab is therapeutically effective for patients with a number of IMIDs other than RA. This review focuses on the perspective of IL-6 blockade therapy for such IL-6-related IMIDs outside of RA.
A considerable number of case reports and preclinical studies have shown the benefit of IL-6 blockade therapy in various IMIDs such as systemic lupus erythematosus, adult-onset Still disease, Takayasu arthritis, polyarteritis nodosa, systemic sclerosis, reactive arthritis, dermatomyositis, and polymyositis.
Blocking IL-6 with tocilizumab can be a therapeutic option for patients with various IMIDs in which overproduction of IL-6 plays a pathological role. Future clinical studies investigating the safety and efficacy will elucidate the clinical benefits of IL-6 blockade therapy for such diseases.
Abstract We have investigated the importance of interleukin-6 (IL-6) in promoting tumor growth and metastasis. In human primary breast cancers, increased levels of IL-6 were found at the tumor ...leading edge and positively correlated with advanced stage, suggesting a mechanistic link between tumor cell production of IL-6 and invasion. In support of this hypothesis, we showed that the IL-6/Janus kinase (JAK)/signal transducer and activator of transcription 3 (Stat3) pathway drives tumor progression through the stroma and metastatic niche. Overexpression of IL-6 in tumor cell lines promoted myeloid cell recruitment, angiogenesis, and induced metastases. We demonstrated the therapeutic potential of interrupting this pathway with IL-6 receptor blockade or by inhibiting its downstream effectors JAK1/2 or Stat3. These clinically relevant interventions did not inhibit tumor cell proliferation in vitro but had profound effects in vivo on tumor progression, interfering broadly with tumor-supportive stromal functions, including angiogenesis, fibroblast infiltration, and myeloid suppressor cell recruitment in both the tumor and pre-metastatic niche. This study provides the first evidence for IL-6 expression at the leading edge of invasive human breast tumors and demonstrates mechanistically that IL-6/JAK/Stat3 signaling plays a critical and pharmacologically targetable role in orchestrating the composition of the tumor microenvironment that promotes growth, invasion, and metastasis.
We investigated the clinical efficacy and safety of tocilizumab (a humanized anti-IL-6 receptor antibody) monotherapy in active rheumatoid arthritis (RA) patients with an inadequate response to low ...dose methotrexate (MTX). In a multicenter, double-blind, randomized, controlled trial, 125 patients were allocated to receive either tocilizumab 8 mg/kg every 4 weeks plus MTX placebo (tocilizumab group) or tocilizumab placebo plus MTX 8 mg/week (control group) for 24 weeks. The clinical responses were measured using the American College of Rheumatology (ACR) criteria and the Disease Activity Score in 28 joints. Serum vascular endothelial growth factor (VEGF) levels were also monitored. At week 24, 25.0% in the control group and 80.3% in the tocilizumab group achieved ACR20 response. The tocilizumab group showed superior ACR response criteria over control at all time points. Additionally, serum VEGF levels were significantly decreased by tocilizumab treatment. The overall incidences of adverse events (AEs) were 72 and 92% (serious AEs: 4.7 and 6.6%; serious infections: 1.6 and 3.3%) in the control and the tocilizumab groups, respectively. All serious adverse events improved by adequate treatment. Tocilizumab monotherapy was well tolerated and provided an excellent clinical benefit in active RA patients with an inadequate response to low dose MTX.
IgG4-related disease (IgG4-RD) is a novel disease entity that includes Mikulicz's disease, autoimmune pancreatitis (AIP), and many other conditions. It is characterized by elevated serum IgG4 levels ...and abundant IgG4-bearing plasmacyte infiltration of involved organs. We postulated that high levels of serum IgG4 would comprise a useful diagnostic tool, but little information is available about IgG4 in conditions other than IgG4-RD, including rheumatic diseases. Several reports have described cutoff values for serum IgG4 when diagnosing IgG4-RD, but these studies mostly used 135 mg/dL in AIP to differentiate from pancreatic cancer instead of rheumatic and other common diseases. There is no evidence for a cutoff serum IgG4 level of 135 mg/dL for rheumatic diseases and common diseases that are often complicated with rheumatic diseases. The aim of this work was to re-evaluate the usual cutoff serum IgG4 value in AIP (135 mg/dL) that is used to diagnose whole IgG4-RD in the setting of a rheumatic clinic by measuring serum IgG4 levels in IgG4-RD and various disorders. We therefore constructed ROC curves of serum IgG4 levels in 418 patients who attended Sapporo Medical University Hospital due to IgG4-RD and various rheumatic and common disorders. The optimal cut-off value of serum IgG4 for a diagnosis of IgG4-RD was 144 mg/dL, and the sensitivity and specificity were 95.10 and 90.76%, respectively. Levels of serum IgG4 were elevated in IgG4-RD, Churg-Strauss syndrome, multicentric Castleman's disease, eosinophilic disorders, and in some patients with rheumatoid arthritis, systemic sclerosis, chronic hepatitis, and liver cirrhosis. The usual cut-off value of 135 mg/dL in AIP is useful for diagnosing whole IgG4-RD, but high levels of serum IgG4 are sometimes observed in not only IgG4-RD but also other rheumatic and common diseases.
Summary Background Systemic-onset juvenile idiopathic arthritis does not always respond to available treatments, including antitumour necrosis factor agents. We investigated the efficacy and safety ...of tocilizumab, an anti-interleukin-6-receptor monoclonal antibody, in children with this disorder. Methods 56 children (aged 2–19 years) with disease refractory to conventional treatment were given three doses of tocilizumab 8 mg/kg every 2 weeks during a 6-week open-label lead-in phase. Patients achieving an American College of Rheumatology Pediatric (ACR Pedi) 30 response and a C-reactive protein concentration (CRP) of less than 5 mg/L were randomly assigned to receive placebo or to continue tocilizumab treatment for 12 weeks or until withdrawal for rescue medication in a double-blind phase. The primary endpoint of the double-blind phase was an ACR Pedi 30 response and CRP concentration of less than 15 mg/L. Patients responding to tocilizumab and needing further treatment were enrolled in an open-label extension phase for at least 48 weeks. The analysis was done by intention to treat. This study is registered with ClinicalTrials.gov , numbers NCT00144599 (for the open-label lead-in and double-blind phases) and NCT00144612 (for the open-label extension phase). Findings At the end of the open-label lead-in phase, ACR Pedi 30, 50, and 70 responses were achieved by 51 (91%), 48 (86%), and 38 (68%) patients, respectively. 43 patients continued to the double-blind phase and were included in the efficacy analysis. Four (17%) of 23 patients in the placebo group maintained an ACR Pedi 30 response and a CRP concentration of less than 15 mg/L compared with 16 (80%) of 20 in the tocilizumab group (p<0·0001). By week 48 of the open-label extension phase, ACR Pedi 30, 50, and 70 responses were achieved by 47 (98%), 45 (94%), and 43 (90%) of 48 patients, respectively. Serious adverse events were anaphylactoid reaction, gastrointestinal haemorrhage, bronchitis, and gastroenteritis. Interpretation Tocilizumab is effective in children with systemic-onset juvenile idiopathic arthritis. It might therefore be a suitable treatment in the control of this disorder, which has so far been difficult to manage. Funding Chugai Pharmaceuticals.
IL-6 is a pleiotropic cytokine with a wide range of biological activities in immune regulation, hematopoiesis, inflammation, and oncogenesis. Its activities are shared by IL-6-related cytokines such ...as leukemia inhibitory factor and oncostatin M. The pleiotropy and redundancy of IL-6 functions have been identified by using a unique receptor system comprising two functional proteins: an IL-6 receptor (IL-6R) and gp130, the common signal transducer of cytokines related to IL-6. Signal transduction through gp130 is mediated by two pathways: the JAK-STAT (Janus family tyrosine kinase-signal transducer and activator of transcription) pathway and the Ras mitogen-activated protein kinase pathway. The negative regulators of IL-6 signaling have also been identified, although the physiological roles of the molecules are not yet fully understood. The pathological roles of IL-6 have also been clarified in various disease conditions, such as inflammatory, autoimmune, and malignant diseases. On the basis of the findings, a new therapeutic approach to block the IL-6 signal using humanized anti-IL-6R antibody for rheumatoid arthritis, Castleman's disease, and multiple myeloma has been attempted.
The graft-versus-tumor (GVT) effect is a potent form of immunotherapy against many hematologic malignancies and some solid tumors. The beneficial GVT effect after allogeneic bone marrow ...transplantation (BMT) is tightly linked to its most significant complication, graft-versus-host disease (GVHD). The role of interleukin-6 (IL-6) after allogeneic BMT is not well understood. This study used a series of complementary knockout and antibody blockade strategies to analyze the impact of IL-6 in multiple clinically relevant murine models of GVHD and GVT.
We examined the effect of the source of IL-6 by analyzing the role IL-6 deficiency in donor T cells, donor bone marrow or in host tissues. We confirmed and extended the relevance of IL-6 deficiency on GVHD and GVT by treating BMT recipients with anti-mouse IL-6 receptor (IL-6R), MR16-1.
Deficiency of IL-6 in donor T cells led to prolongation of survival. Total inhibition of IL-6 with MR16-1 caused an even greater reduction in GVHD-induced mortality. The reduction in GVHD was independent of the direct effects on T effector cell expansion or donor regulatory T cells. GVT responses were preserved after treatment with MR16-1.
MR16-1 treatment reduced GVHD and preserved sufficient GVT. Tocilizumab, a humanized anti-IL-6R monoclonal antibody (mAb), is approved in several countries including the United States and European Union for the treatment of rheumatoid arthritis and other inflammatory diseases. Blockade of IL-6 with anti-IL-6R mAb therapy may be testable in clinical trials as an adjunct to prevent GVHD in BMT patients without a significant loss of GVT.
To understand the risk of particle formation in glass vials, we investigated the correlation between vial surface condition and alminum (Al) or silicon (Si) elution using various suppliers’ vials ...with or without surface treatment. The elution of Si, which can also be an indicator of Al elution, consists of two phases; the first phase is influenced by roughness of the glass surface at the time of filling, and the second phase is dependent on the fundamental elution rate from the glass tube. When vials were filled with citrate buffer at pH 7, vials with varied surface conditions showed the most obvious differences in Al and Si elution. Sulfur-treated vials showed slightly lower Al and Si elution than the non-treated vials. It is considered that this effect of the sulfur treatment on elution is due to the surface being smoothed during heat treatment after the washing process. Different from the sulfur treatment, silicon dioxide (SiO2)-coated vials hardly showed any Al elution as long as the surface was fully coated with the SiO2 layer. It was found that the protective effect of the SiO2 layer against Al elution is more effective in a vial filled with a solution having a lower pH, due to the lower Si dissolving rate occurring at a lower pH. As shown above, pre-measuring the Si and Al present in a citrate buffer at pH 7 placed within a glass container can be a useful tool for selecting the appropriate container for liquid drugs.