Tocilizumab dramatically ameliorated life-threatening diarrhea due to secondary amyloidosis associated with rheumatoid arthritis

Case report: Rapid development of amyloid A amyloidosis in temporal arteritis with SAA1.3 allele; An unusual case of intestinal amyloidosis secondary to temporal arteritis

Temporal arteritis (TA) is a large-vessel vasculitis mostly seen in older patients. Amyloid A (AA) amyloidosis secondary to a chronic inflammation induces multiple organ dysfunctions, including a dysfunction of the gastrointestinal tract. Herein, we present a case of TA complicated by AA amyloidosis that was resistant to oral and intravenous steroids. An 80-year-old man with a history of new-onset headache, jaw claudication, and distended temporal arteries was referred to our department. On admission, the patient presented with tenderness and a subcutaneous temporal nodule in both temple arteries. Ultrasonography of the nodule revealed an anechoic perivascular halo surrounding the right temporal artery. Following the diagnosis of TA, high-dose prednisolone therapy was initiated. However, the patient presented with recurrent abdominal pain and refractory diarrhea. Due to the unclear origin of refractory diarrhea, an extensive workup, including biopsy of the duodenal mucosa, was performed. Endoscopy revealed chronic inflammation in the duodenum. Immunohistochemical analysis of duodenal mucosal biopsy samples revealed AA amyloid deposition resulting in the diagnosis of AA amyloidosis. After tocilizumab (TCZ) administration, refractory diarrhea reduced; however, the patient died of intestinal perforation 1 month after the start of TCZ administration. Gastrointestinal involvement was the main clinical manifestation of AA amyloidosis in the present case. This case highlights the importance of bowel biopsy screening for amyloid deposition in patients with unexplained gastrointestinal tract symptoms, even in a recent onset of large-vessel vasculitis. In the present case, the carriage of the SAA1.3 allele likely contributed to the rare association of AA amyloidosis with TA.

Case of successful use of sarilumab in secondary renal amyloidosis in a patient with rheumatoid arthritis

Clinical observation of the successful use of the interleukin 6 (IL6) inhibitor sarilumab in secondary renal amyloidosis in a patient with active seropositive rheumatoid arthritis, is presented. This complication was confirmed by biopsy of rectum. The presented clinical example demonstrates a fairly rapid, within five years from the onset of the disease, the development of secondary renal amyolidosis with the formation of a persistent nephrotic syndrome that is resistant to therapy with cyclophosphamide and rituximab. Prescription of the IL6 inhibitor tocilizumab contributed to a decrease in the clinical and laboratory activity of the underlying disease, a decrease in the severity of daily proteinuria, but did not allow to achieve the full effect. The use of another IL6 inhibitor – sarilumab, led to a complete regression of nephrotic syndrome with normalization of general urine analysis, biochemical blood tests – total protein, albumin, total cholesterol, against the background of stable clinical and laboratory remission of rheumatoid arthritis.

Biologic therapy for amyloid A amyloidosis secondary to rheumatoid arthritis treated with interleukin 6 therapy: Case report and review of literature

INTRODUCTION

Secondary amyloidosis is a rare complication of rheumatoid arthritis (RA) that is histologically characterized by the deposition of amyloid fibrils in target organs, such as the kidneys and gastrointestinal tract. Controlling the inflammatory response is essential to prevent organ dysfunction in amyloid A (AA) amyloidosis secondary to RA, and no clear treatment strategy exists.

PATIENT CONCERNS AND DIAGNOSIS

A 66-year-old woman with RA, who had been treated with disease-modifying anti-rheumatic drugs for 1 year, presented with recurrent abdominal pain and prolonged diarrhea. Endoscopy showed chronic inflammation, and colon tissue histology confirmed AA amyloidosis.

INTERVENTIONS AND OUTCOMES

After tocilizumab therapy was begun, her diarrhea and abdominal pain subsided, and articular symptoms improved. Biologic drugs for RA have been used in patients with secondary AA amyloidosis, including tumor necrosis factor and Janus kinase inhibitors, interleukin 6 blockers, and a T cell modulator. Here, we systematically review existing case reports and compare the outcomes of RA-related AA amyloidosis after treatment with various drugs.

CONCLUSION

The data indicate that biologic drugs like tocilizumab might be treatments of choice for AA amyloidosis secondary to RA.

AA amyloidosis - Benefits and prospects of IL-6 inhibitors

AA amyloidosis may develop in patients with active chronic inflammation. Serum amyloid A (SAA), the precursor of the AA protein, is strongly amplified in the liver under the stimulation of inflammation-associated cytokines, such as IL-6, TNF, and IL-1. Sustained inflammation, aging, and polymorphisms in the SAA1.3 genotype are dependent risk factors for the formation of AA amyloidosis. The most rational treatment strategy for AA amyloidosis is to inhibit the production of SAA. Treatments for AA amyloidosis involving biologics have recently been emphasized. TNF inhibitors and abatacept reduce SAA levels; however, complete normalization is not always achieved. IL-6 inhibitors may normalize SAA levels in most patients in whom a sufficient concentration of medication is maintained in the blood. Therefore, treatments with IL-6 inhibitors represent an excellent therapeutic strategy for AA amyloidosis and have been verified by recent studies.

Clinical implications of gastrointestinal symptoms in systemic amyloidosis

BACKGROUND

Gastrointestinal (GI) symptoms in systemic amyloidosis patients are poorly characterized. This purpose of this study is to define the epidemiology and clinical implications of such symptoms.

METHODS

This was a retrospective cohort study of 583 amyloid patients seen at a tertiary referral center. Of 96 symptomatic patients, 82 received endoscopic biopsies, subsequently grouped into those with histologic evidence of GI amyloid (biopsy proven) vs without (biopsy absent).

KEY RESULTS

16.8% of patients had GI symptoms, and had more abnormal NT-proBNP, cardiac ejection fraction, serum albumin, and alkaline phosphatase (P < .01). Of those who received endoscopy, the sites of highest diagnostic yield were stomach, duodenum and colon. The most common symptom was abdominal pain, nausea, or vomiting (50.0%). Of the symptomatic patients, only 37 (45%) had biopsy proven GI amyloid. Biopsy proven patients more often had cardiac involvement (P < .005), and more often received hematologic therapy or transplant (P = .01). Biopsy absent patients had more frequent neurologic involvement (P = .17). Biopsy status had no significant correlation with other indicators of amyloid burden, GI symptoms or management.

CONCLUSIONS & INFERENCES

Nearly one in six amyloid patients have GI symptoms, and half do not have GI amyloid. The type of symptom does not predict endoscopic findings. Most biopsy absent patients are not managed as a functional disorder despite no alternative etiology. Gastroenterologists may have an increased role to play in the care of systemic amyloidosis beyond performing endoscopies, such as evaluating cardiac amyloid patients for concurrent GI amyloid.

Gastrointestinal perforation in light chain amyloidosis in the era of novel agent therapy - a case series and review of the literature

Gastrointestinal (GI) perforation is remarkably rare in patients with light chain (AL) amyloidosis and has not yet been reported in patients with AL amyloidosis treated with novel agents. Only 24 cases of GI perforation have previously been reported in the setting of AL amyloidosis of which 15 had available information in English. All 15 did not receive novel agent therapy and six died early after experiencing GI perforation. This study reports the characteristics and outcome of AL patients that developed GI perforation in the era of novel agent treatment. Seven patients were reviewed. In two patients, GI perforation was the presenting symptom of AL amyloidosis, whereas five patients developed GI perforations following initiation of an anti-AL therapy (three after bortezomib-based, 1 after lenalidomide-based and 1 after thalidomide-based therapy). All patients underwent surgery and survived the perforation. Treatment was renewed following surgery in six of seven patients, with no further GI complications. In conclusion, GI perforation in AL amyloidosis is rare and mostly reported after treatment initiation. Urgent surgery appears to be lifesaving and renewal of the anti-AL novel therapy appears to be safe, with no significant risk for re-perforation or GI toxicity. Prognosis in these patients is related to severity of the disease and response to therapy rather than the development of GI perforation.

[Interleukin-6 inhibition as a potential therapeutic target in rheumatic diseases]

As a pro-inflammatory cytokine, the 21-kDa glycoprotein interleukin-6 (IL-6) plays a crucial role in the initiation of acute inflammation, as well in the perpetuation of a chronic inflammatory immune response. Thus, IL-6 might be involved in the pathogenesis of various autoimmune diseases. So far, the IL-6-rezeptor-antibody tocilizumab (TCZ, RoActemtra®) is the only approved drug for the treatment of IL-6-mediated disease, including rheumatoid arthritis (RA), systemic juvenile idiopathic (sJIA) and polyarticular juvenile arthritis (pJiA), as well as Castleman's disease (in Japan only). In recent years, an emerging number of case reports and small uncontrolled case series have reported on the successful treatment of various other chronic inflammatory diseases, which has resulted in the idea of a broad therapeutic potential for IL-6 blockade. Numerous IL-6 targets are currently in phase II/III study programs for RA as well as for other indications. This review focuses on the development of tocilizumab and other IL-6 targets as a therapeutic option for various diseases in rheumatology.

Effects of Biologic Agents in Patients with Rheumatoid Arthritis and Amyloidosis Treated with Hemodialysis

Objective Our objective was to examine the safety and effects of therapy with biologics on the prognosis of rheumatoid arthritis (RA) patients with reactive amyloid A (AA) amyloidosis on hemodialysis (HD). Methods Twenty-eight patients with an established diagnosis of reactive AA amyloidosis participated in the study. The survival was calculated from the date of HD initiation until the time of death, or up to end of June 2015 for the patients who were still alive. HD initiation was according to the program of HD initiation for systemic amyloidosis patients associated with RA. Results Ten patients had been treated with biologics before HD initiation for a mean of 28.2 months (biologic group), while 18 had not (non-biologic group). HD was initiated in patients with similar characteristics except for the tender joint count, swollen joint count, and disease activity score (DAS)28-C-reactive protein (CRP). History of biologics showed that etanercept was frequently used for 8 patients as the first biologic. There was no significant difference in the mortality rate according to a Kaplan-Meier analysis (p=0.939) and or associated risk of death in an age-adjusted Cox proportional hazards model (p=0.758) between both groups. Infections were significantly more frequent causes of death in the biologic group than in the non-biologic group (p=0.021). However, treatment with biologics improved the DAS28-CRP score (p=0.004). Conclusion Under the limited conditions of AA amyloidosis treated with HD, the use of biologics might affect infection and thus may not improve the prognosis. Strict infection control is necessary for the use of biologics with HD to improve the prognosis.

Analysis of patents on anti-rheumatoid arthritis therapies issued in China

INTRODUCTION

The etiology of rheumatoid arthritis (RA) is complex and diverse. Chronic inflammatory processes with joint dysfunction can cause permanent disability. Therefore, the development of new drugs and therapies for RA is very important.

AREAS COVERED

This review analyzes the existing patents on anti-RA products in China to help pharmaceutical companies and individuals patent potential candidate drugs for RA treatment.

EXPERT OPINION

Three hundred and seventeen patents were analyzed, including 172 patents for Traditional Chinese Medicines (TCMs, 54.2%), 65 for synthetic compounds (20.5%), 55 for biological products (17.4%) and 25 patents for the drug preparation process (7.9%). Among the TCM patents, 73.8% were of various preparations for different Chinese medicines, 23.8% were of herbal extracts and 2.3% were of herbal extract derivatives. Synthetic compounds were involved in more than 30 targets, some small-molecule drugs that target signaling kinases such as p38 MAPK, Janus kinase may become important directions in the management of RA. Biological disease-modifying antirheumatic drugs (bDMARDs) are the most efficacious drugs for RA treatment. As the classic therapeutic target in RA, TNF-α has the largest number of bDMARD patents. In addition, it is expected that new targets such as high-mobility group protein B1, thioredoxin domain-containing protein 5 (TXNDC5) and B lymphocyte stimulator (BlyS) will play a significant role in RA as potential targets for new treatments. The largest number of all the published patent applications are claiming TCMs, which may provide substantial new information for anti-RA drug development. The largest number of all the published patent applications are claiming TCMs, which may provide huge information for anti-RA drug development.

Juvenile idiopathic arthritis complicated by amyloidosis with secondary nephrotic syndrome - effective treatment with tocilizumab

A case report of a boy with juvenile idiopathic arthritis since the age of 2 years, generalized onset, complicated by nephrotic syndrome due to secondary type A amyloidosis is presented.

In the patient the disease had an especially severe course, complicated by frequent infections, making routine treatment difficult. Amyloidosis was diagnosed in the 5^th year of the disease based on a rectal biopsy. Since the disease onset the boy has been taking prednisolone and sequentially cyclosporine A, methotrexate, chlorambucil, etanercept, and cyclophosphamide. Clinical and laboratory remission was observed after treatment with tocilizumab. After 42 months of treatment with tocilizumab the boy's condition is good. There is no pain or joint edema, and no signs of nephrotic syndrome.

AA amyloidosis treated with tocilizumab: case series and updated literature review

BACKGROUND

In published case reports, tocilizumab (TCZ) has shown good efficacy for AA amyloidosis in almost all patients. We investigated the efficacy and safety of TCZ in AA amyloidosis in a multicentre study of unselected cases.

METHODS

We e-mailed rheumatology and internal medicine departments in France, Switzerland and North Africa by using the Club Rhumatismes Inflammation (CRI) network and the French TCZ registry, Registry RoAcTEmra (REGATE), to gather data on consecutive patients with histologically proven AA amyloidosis who had received at least one TCZ infusion. Efficacy was defined as a sustained decrease in proteinuria level and/or stable or improved glomerular filtration rate (GFR) and by TCZ maintenance.

RESULTS

We collected 12 cases of AA amyloidosis treated with TCZ as monotherapy (mean age of patients 63 ± 16.2 years, amyloidosis duration 20.6 ± 31.3 months): eight patients had rheumatoid arthritis (RA), six with previous failure of anti-tumor necrosis factor α (anti-TNF-α) therapy. In total, 11 patients had renal involvement, with two already on hemodialysis (not included in the renal efficacy assessment). For the nine other patients, baseline GFR and proteinuria level were 53.6 ± 32.8 mL/min and 5 ± 3.3 g/24 h, respectively. The mean follow-up was 13.1 ± 11 months. TCZ was effective for six of the eight RA patients (87.5%) according to European League Against Rheumatism response criteria (four good and two moderate responders). As expected, C-reactive protein (CRP) level decreased with treatment for 11 patients. Renal amyloidosis (n = 9) progressed in three patients and was stabilized in three. Overall, three patients showed improvement, with sustained decrease in proteinuria level (42%, 82% and 96%). Baseline CRP level was higher in subsequent responders to TCZ than other patients (p = 0.02). Among the six RA patients with previous anti-TNF-α therapy, amyloidosis was ameliorated in one and stabilized in three. Three serious adverse events occurred (two diverticulitis and one major calciphylaxia due to renal failure). Finally, 7 of 12 (58%) patients continued TCZ.

CONCLUSIONS

The efficacy of TCZ for AA amyloidosis varies depending on the inflammatory status at treatment onset. Discrepancies between our study of unselected consecutive patients and reported cases may be due to publication bias. These results support further prospective trials of TCZ for AA amyloidosis.

Therapeutic Benefits of Tocilizumab Vary in Different Organs of a Patient with AA Amyloidosis

Systemic reactive AA amyloidosis is a life-threatening complication of chronic inflammatory diseases. Anti-interleukin-6 receptor, tocilizumab (TCZ), has been shown to improve clinical symptoms of patients with AA amyloidosis, accompanied with regression of the amyloid deposition. We report a case of AA amyloidosis evaluated by histology of multiple organs before and after TCZ treatment. A woman in her 60s with rheumatoid arthritis was referred to our hospital because of cardiac and renal dysfunction. A gastric and renal biopsy revealed the deposition of AA amyloid, and echocardiography revealed concentric left ventricular hypertrophy. Her estimated glomerular filtration rate was decreased to 8.6 mL/min/1.73 m², and B-type natriuretic peptide, C-reactive protein, and serum amyloid A protein were significantly elevated. TCZ treatments markedly decreased her serum amyloid A protein and C-reactive protein levels, but hemodialysis was required 1 year later. Endoscopic gastric rebiopsy 3 years after initiation of TCZ treatments revealed the regression of amyloid deposition and echocardiography revealed improvement of her left ventricular hypertrophy. However, a renal rebiopsy revealed that the amyloid deposition had not regressed. In conclusion, these observations suggest that the therapeutic effects of TCZ can vary among organs in patients with AA amyloidosis.

Comparison of the clinical utility of tocilizumab and anti-TNF therapy in AA amyloidosis complicating rheumatic diseases

OBJECTIVES

Anti-cytokine therapy is reportedly useful in amyloid A (AA) amyloidosis complicating rheumatic diseases. However, to date no studies have directly compared the utility of tumour necrosis factor (TNF) inhibition to that of interleukin-6. The aim of our retrospective study was to compare the clinical utility of tocilizumab (TCZ) and anti-TNF (TNF inhibitor) therapy.

METHODS

We studied 42 patients treated with anti-cytokine agents at our hospital: 31 had received a single agent, ten had received two agents and one had received three agents. Patients were divided into a TCZ group (22 patients) and a TNF inhibitor group (32 patients). The main parameters compared were treatment retention rate, serum amyloid A (SAA) profile, renal function profile and clinical disease activity index.

RESULTS

The 5-year retention rates were 90.4 (TCZ group) and 34.3 % (TNF inhibitor group) (p = 0.0154, log-rank test). The median SAA fell from 219.2 μg/mL at treatment initiation to 5.0 μg/mL at last observation (TCZ), and from 143.6 to 38.1 μg/mL (TNF inhibitor) (p = 0.0194). Estimated glomerular filtration rate was improved in 72.7 (TCZ) and 34.4 % (TNF inhibitor) of patients (p = 0.0062). The rates of clinical remission or low disease activity at last observation for the TCZ and TNF inhibitor groups were 72.7 and 40.7 % (p = 0.0201), respectively.

CONCLUSIONS

Based on these results, we conclude that TCZ was of greater clinical utility than anti-TNF therapy in our patients with AA amyloidosis complicating rheumatic diseases.

AA amyloidosis in a polyarteritis nodosa patient treated with tocilizumab

Amyloid A (AA) (secondary) amyloidosis represents a severe complication of chronic inflammatory diseases. Since pathogenic mechanisms point to the central role of interleukin 6 (IL-6) in the process of amyloid AA generation, IL-6 blockade seems an attractive therapeutic option. We report a case of a patient with polyarteritis nodosa complicated by AA amyloidosis treated with tocilizumab.

Study on the safety and efficacy of tocilizumab, an anti-IL-6 receptor antibody, in patients with rheumatoid arthritis complicated with AA amyloidosis

OBJECTIVES

Although treatment of rheumatoid arthritis (RA) has progressed by the use of biologics, amyloid A (AA) amyloidosis is still an intractable complication in patients with RA. In the present study, safety and efficacy of 1-year treatment with an anti-IL-6 receptor antibody tocilizumab (TCZ) on RA and AA amyloidosis were estimated.

METHODS

TCZ (8 mg/kg every 4 weeks) was administered to five RA patients complicated with AA amyloidosis. The primary end point was improvement in renal dysfunction and the secondary end point was CDAI at 1 year after the treatment.

RESULTS

An improvement in the renal dysfunction, including urinary protein secretion, was found, in four patients including two patients who were refractory to etanercept, with a remarkable decrease of SAA concentration, and the progression of organ dysfunction was prevented at 1 year in all patients treated with TCZ. The mean clinical disease activity index decreased from 33.9 to 4.7 (p = 0.012) in five patients treated with TCZ for 1 year. Three non-serious adverse events were observed in two patients.

CONCLUSIONS

TCZ ameliorates renal dysfunction in RA patients complicated with AA amyloidosis who are refractory to conventional therapies, thereby suggesting that TCZ has a potential to regulate AA amyloidosis.

Tocilizumab: a novel humanized anti-interleukin 6 (IL-6) receptor antibody for the treatment of patients with non-RA systemic, inflammatory rheumatic diseases

Tocilizumab is a highly effective therapeutic agent for the treatment of rheumatoid arthritis and systemic juvenile idiopathic arthritis. Furthermore, a large amount of case study data reveals that tocilizumab can be an effective therapy for not only rheumatoid arthritis but also for other mostly rare inflammatory rheumatic diseases. By blocking the interleukin-6 pathway tocilizumab can be a useful therapeutic alternative when conventional treatment fails. It is successful in treating diseases such as the adult-onset Still's disease, amyloidosis, giant cell arteritis, multiple myeloma, polymyalgia rheumatica, relapsing polychondritis, remitting seronegative symmetrical synovitis with pitting edema-syndrome, systemic lupus erythematosus, systemic sclerosis, and Takayasu arteritis. Studies underway are now recruiting patients to acquire further data on treating patients with non-rheumatic arthritis, inflammatory diseases. This review focuses on tocilizumab as a promising agent for treating rare and orphan diseases in rheumatology for which no satisfactory treatment is yet available.

Tocilizumab: An Updated Review of Its Use in the Treatment of Rheumatoid Arthritis and Its Application for Other Immune-Mediated Diseases

Interleukin-6 (IL-6), produced by a variety of cells, is a typical cytokine featuring redundancy and pleiotropic activity. IL-6 is promptly and transiently synthesized in response to infections or injuries, and participates in host defense by inducing immune responses, hematopoiesis, and acute-phase reactions. However, since its abnormal persistent production of mostly unknown etiology plays an important pathological role in the development of various immune-mediated diseases, a humanized anti-IL-6 receptor monoclonal antibody, tocilizumab, was developed and is now used as an innovative biologic for rheumatoid arthritis in more than 90 countries. Several factors strongly suggest that a IL-6 blockade strategy may have a broad application for the treatment of various immune-mediated diseases. These factors include favorable results of pilot or case studies with off-label use of tocilizumab, pathological analyses of the contribution of IL-6 to the development of immune-mediated diseases, and the potential capability of tocilizumab to both repair an imbalance of effector T cell subsets and to suppress pathologic autoantibody production. However, clinical trials to evaluate the efficacy and safety of tocilizumab for these diseases are essential. Furthermore, clarification of the cell source of IL-6 production and of the mechanisms through which dysregulated continuous IL-6 synthesis is induced constitutes an important issue for future studies into the pathogenesis of diseases.

Prevalence of gastroesophageal reflux disease symptoms and related factors in patients with rheumatoid arthritis

Gastroesophageal reflux disease (GERD) is common in patients with many chronic diseases, but has not been well recognized in rheumatoid arthritis (RA). We investigated the prevalence of GERD symptoms in 278 outpatients with RA and their association with such clinical factors as age, sex, height, weight, body mass index, medications drugs, and functional status evaluated by the Modified Health Assessment Questionnaire (MHAQ). GERD symptoms were evaluated by Frequency Scale for the Symptoms of GERD (FSSG). The mean FSSG score for all patients was 5.6, and 82 patients were considered to have GERD symptoms (FSSG score ≥8), thus the overall prevalence of GERD symptoms was 29.5%. MHAQ score and height were significantly higher and lower, respectively, and prednisolone usage was significantly more in the patients with GERD symptoms than those without. These three clinical factors were also significantly associated with GERD symptoms by univariate logistic regression. Multivariate logistic regression analysis demonstrated that MHAQ was the only clinical factor related to GERD symptoms. In conclusion, the prevalence of GERD symptoms in RA patients was high and strongly associated with decreased functional status, suggesting that physicians should pay attention to GERD symptoms in RA management, especially for patients with low functional status.

Targeting interleukin-6: all the way to treat autoimmune and inflammatory diseases

Interleukin (IL)-6, a cytokine featuring redundancy and pleiotropic activity, contributes to host defense against acute environmental stress, while dysregulated persistent IL-6 production has been demonstrated to play a pathological role in various autoimmune and chronic inflammatory diseases. Targeting IL-6 is thus a rational approach to the treatment of these diseases. Indeed, clinical trials of tocilizumab, a humanized anti-IL-6 receptor antibody have verified its efficacy and tolerable safety for patients with rheumatoid arthritis, Castleman's disease and systemic juvenile idiopathic arthritis, resulting in approval of this innovative biologic for treatment of these diseases. Moreover, a considerable number of case reports and pilot studies of off-label use of tocilizumab point to the beneficial effects of tocilizumab for a variety of other phenotypically different autoimmune and chronic inflammatory diseases. Elucidation of the source of IL-6 and of mechanisms through which IL-6 production is dysregulated can thus be expected to lead to clarification of the pathogenesis of various diseases.

Procalcitonin is a specific marker for detecting bacterial infection in patients with rheumatoid arthritis

OBJECTIVE

Rheumatoid arthritis (RA) is a chronic inflammatory disease accompanied by many complications, and serious infections are associated with many of the advanced therapeutics used to treat it. We assessed serum procalcitonin (PCT) levels to distinguish bacterial infection from other complications in patients with RA.

METHODS

One hundred eighteen patients experiencing an RA flare, noninfectious complication of RA or its treatment, nonbacterial infection, or bacterial infection were studied. Serum PCT concentrations were determined with a chemiluminescent enzyme immunoassay.

RESULTS

All patients experiencing an RA flare showed negative PCT levels (≤ 0.1 ng/ml; n = 18). The PCT level was higher in the bacterial infection group (25.8% had levels ≥ 0.5 ng/ml) than in the other 3 groups (0.0-4.3% had levels ≥ 0.5 ng/ml) and the difference was significant among groups (p = 0.003). Conversely, no statistically significant difference was observed among the groups with C-reactive protein (CRP) concentration ≥ 0.3 mg/dl (p = 0.513), white blood cell (WBC) count > 8500/mm(3) (p = 0.053), or erythrocyte sedimentation rate (ESR) > 15 mm/h (p = 0.328). The OR of high PCT level (≥ 0.5 ng/ml) for detection of bacterial infection was 19.13 (95% CI 2.44-149.78, p = 0.005). Specificity and positive likelihood ratio of PCT ≥ 0.5 ng/ml were highest (98.2% and 14.33, respectively) for detection of bacterial infection, although the sensitivity was low (25.8%).

CONCLUSION

Serum PCT level is a more specific marker for detection of bacterial infection than either CRP, ESR, or WBC count in patients with RA. High PCT levels (≥ 0.5 ng/ml) strongly suggest bacterial infection. However, PCT < 0.5 ng/ml, even if < 0.2 ng/ml, does not rule out bacterial infection and physicians should treat appropriately.

Treatment with Biologic Agents Improves the Prognosis of Patients with Rheumatoid Arthritis and Amyloidosis

Objective.

Reactive amyloid A (AA) amyloidosis is a serious and life-threatening systemic complication of rheumatoid arthritis (RA). We evaluated the safety of therapy with anti-tumor necrosis factor and anti-interleukin 6 biologic agents in RA patients with reactive AA amyloidosis, together with prognosis and hemodialysis (HD)-free survival, in comparison with patients with AA amyloidosis without such therapy.

Methods.

One hundred thirty-three patients with an established diagnosis of reactive AA amyloidosis participated in the study. Clinical data were assessed from patient records at the time of amyloid detection and administration of biologics. Survival was calculated from the date when amyloid was first demonstrated histologically or the date when biologic therapy was started until the time of death or to the end of 2010 for surviving patients. Patients who had started HD were selected for inclusion only after the presence of amyloid was demonstrated.

Results.

Fifty-three patients were treated with biologic agents (biologic group) and 80 were not (nonbiologic group). Survival rate was significantly higher in the biologic group than in the nonbiologic group. Nine patients in the biologics group and 33 in the nonbiologic group started HD. Biologic therapy had a tendency for reduced risk of initiation of HD without any statistical significance.

Conclusion.

Patients with amyloidosis have a higher mortality rate, but the use of biologic agents can reduce risk of death. The use of biologics may not significantly influence the HD-free survival rate.

Immunotherapeutic implication of IL-6 blockade

IL-6 is a cytokine featuring redundancy and pleiotropic activity. While IL-6 contributes to host defense against acute environmental stress, continuous IL-6 production plays a significant pathological role in various autoimmune and chronic inflammatory diseases. To counter this drawback, tocilizumab, a humanized anti-IL-6 receptor antibody, was developed. Clinical trials have verified the efficacy of tocilizumab for patients with rheumatoid arthritis, Castleman's disease and systemic juvenile idiopathic arthritis, resulting in approval of this innovative biologic for their treatment. Moreover, a considerable number of case reports and pilot studies have indicated the beneficial effects of tocilizumab on other autoimmune and chronic inflammatory diseases. Further clinical studies to evaluate the efficacy and safety of tocilizumab for these diseases are essential.

Tocilizumab improves cardiac disease in a hemodialysis patient with AA amyloidosis secondary to rheumatoid arthritis

A 58-year-old Japanese woman on hemodialysis (HD) was admitted for intractable rheumatoid arthritis. Even after HD was started due to end-stage renal failure in 2004, her arthropathy worsened. A soluble tumor necrosis factor receptor inhibitor (etanercept at 25 mg twice weekly), tacrolimus (2 mg daily), and prednisolone (10 mg daily) had been administered since 2005, but high disease activity had persisted. She was admitted to our hospital in July 2007. C-reactive protein (CRP) was 6.8 mg/dL, and the DAS-CRP score was calculated to be 8.3. The cardiothoracic ratio (CTR) was 62% on a chest radiograph, but dialysis hypotension was remarkable. Left ventricular mass (LVM) was calculated as 320 g using echocardiography. Endoscopic biopsy of the stomach and duodenum revealed heavy deposition of AA amyloid. Etanercept was discontinued and tocilizumab was started at a dose of 320 mg (8 mg/kg) monthly. Even after predonisolone and tacrolimus were tapered gradually and discontinued because of her good response, CRP and DAS-CRP became 0.0 mg/dL and 1.5, respectively. In September 2011, re-evaluation was performed. CTR was reduced to 51% and LVM was decreased to 180 g. Endoscopic biopsy of the stomach and duodenum revealed disappearance of AA amyloid. Although AA amyloidosis of the gastrointestinal tract has already been reported to be improved by tocilizumab, this is the first report on improvement of myocardial hypertrophy as well as dialysis hypotension.

Tocilizumab for the treatment of rheumatoid arthritis and other systemic autoimmune diseases: current perspectives and future directions

Interleukin (IL)-6 is a cytokine featuring redundancy and pleiotropic activity. While IL-6, when transiently produced, contributes to host defense against acute environmental stress, continuous dysregulated IL-6 production plays a significant pathological role in several systemic autoimmune diseases. In response to the expectation that IL-6 blockade would constitute a novel therapeutic strategy for the treatment of these diseases, tocilizumab, a humanized anti-IL-6 receptor antibody, was developed. Clinical trials have verified the efficacy and the safety of tocilizumab for patients with rheumatoid arthritis, resulting in approval of this innovative biologic for the treatment of rheumatoid arthritis in more than 90 countries worldwide. Pathological analyses of the effect of IL-6 on the development of autoimmune diseases and a considerable number of case reports and pilot studies have also indicated the beneficial effects of this antibody on other systemic autoimmune diseases, including systemic lupus erythematosus, systemic sclerosis, polymyositis, and large-vessel vasculitis.

Successful use of tocilizumab in a patient with nephrotic syndrome due to a rapidly progressing AA amyloidosis secondary to latent tuberculosis

AA (secondary) amyloidosis is one of the most severe and uncommon complications of several rheumatic disorders and chronic infections such as tuberculosis (TB). Successful treatment depends on the control of the underlying inflammatory process, what can lead to an improvement or a regression in organ dysfunction. If the disorder persists, it has been reported in some cases of AA amyloidosis secondary to rheumatic diseases, that the use of biologic therapy is so far the only opportunity to reduce the development of AA amyloidosis and to reverse established deposits. We report herein a case of a latent TB infection complicated by a life-threatening AA amyloidosis presented as nephrotic syndrome. After an adequate antituberculostatic treatment, AA amyloidosis remained active and Tocilizumab (TCZ) was started with a dramatic resolution of the proteinuria, stabilization of the amyloid deposits and improvement in general condition.

Therapeutic targeting of the interleukin-6 receptor

Interleukin (IL)-6 is a typical cytokine featuring redundancy and pleiotropic activity. It contributes to host defense against pathogens, but dysregulation of IL-6 production plays a significant pathological role in various autoimmune and inflammatory diseases. Because IL-6 blockade was expected to constitute a novel strategy for the treatment of such diseases, tocilizumab, a humanized anti-IL-6 receptor antibody (anti-IL-6RAb), was developed. Clinical trials have demonstrated the efficacy of anti-IL-6RAb for patients with rheumatoid arthritis, Castleman's disease, and juvenile idiopathic arthritis, resulting in approval of this innovative biologic for the treatment of these diseases, and it can be expected to become a novel drug for various other autoimmune and inflammatory diseases. In murine models of autoimmune diseases, anti-IL-6RAb induces Treg and inhibits Th17 and/or Th1 differentiation, indicating that anti-IL-6RAb may be able to repair Th17/Treg imbalance in human diseases as well.

Tocilizumab for the treatment of rheumatoid arthritis

Tocilizumab is a humanized anti-IL-6 receptor monoclonal antibody, which binds to circulating soluble IL-6 receptor and membrane-expressed IL-6 receptor, inhibiting IL-6 binding to both forms of IL-6 receptor. Several Phase III clinical trials demonstrate the clinical efficacy of tocilizumab as monotherapy or with disease-modifying anti-rheumatic drugs for adult patients with moderately to severely active rheumatoid arthritis. Tocilizumab in combination with methotrexate after 24 weeks of treatment could induce disease remission in 30% of patients with rheumatoid arthritis refractory to anti-TNF antagonist therapy. The most common adverse reactions reported in clinical studies are upper respiratory tract infection, nasopharyngitis, headache, hypertension and mild, reversible increases in alanine aminotransferase enzymes. Serious adverse reactions include infections, gastrointestinal perforations and hypersensitivity reactions, including anaphylaxis. The clinical efficacy and safety of tocilizumab has led to the approval of this innovative drug for the treatment of rheumatoid arthritis in more than 70 countries worldwide.

Anti-interleukin-6 receptor antibody, tocilizumab, for the treatment of autoimmune diseases

Interleukin (IL)-6 is a cytokine with multiple biological activities. It contributes to host defense against pathogens, whereas accelerated production of IL-6 plays a significant pathological role in various diseases. Clinical trials have demonstrated the efficacy of tocilizumab, a humanized anti-IL-6 receptor antibody, for patients with rheumatoid arthritis, Castleman's disease or juvenile idiopathic arthritis, leading to approval of this innovative drug for the treatment of these diseases. Since IL-6 has been demonstrated to play a significant role in the development of various other autoimmune and inflammatory diseases, tocilizumab can be expected to become a novel drug for such diseases as well.

Excellent therapeutic effect of tocilizumab on intestinal amyloid a deposition secondary to active rheumatoid arthritis

A 64-year-old woman suffering from progressive amyloid A (AA) amyloidosis of the gastrointestinal (GI) tract, associated with active rheumatoid arthritis, was transferred to our hospital due to hypovolemic shock. Although intensive care, including treatment with prednisolone and methotrexate, improved the hypovolemic shock, paralytic ileus became dominant instead of the marked diarrhea, suggesting the terminal stage of AA amyloidosis of the GI tract. Thus, we administered tocilizumab, a humanized anti-interleukin 6 receptor antibody (8 mg/kg, repeated every 4 weeks). Two weeks after the first injection of tocilizumab, serum AA rapidly returned to their normal ranges in accordance with the amelioration of paralytic ileus and systemic joint pain. Surprisingly, after three courses of tocilizumab treatment, colon biopsy revealed no amyloid deposition. Tocilizumab is a promising agent to treat secondary AA amyloidosis by strongly suppressing serum AA levels.