Factors associated with fatal outcome of leflunomide-induced lung injury in Japanese patients with rheumatoid arthritis

Managing the Risk of Lung Toxicity with Trastuzumab Deruxtecan (T-DXd): A Canadian Perspective

Ongoing advances in precision cancer therapy have increased the number of molecularly targeted and immuno-oncology agents for a variety of cancers, many of which have been associated with a risk of pulmonary complications, among the most concerning being drug-induced interstitial lung disease/pneumonitis (DI-ILD). As the number of patients undergoing treatment with novel anticancer agents continues to grow, DI-ILD is expected to become an increasingly significant clinical challenge. Trastuzumab deruxtecan (T-DXd) is an antibody-drug conjugate targeting human epidermal growth factor receptor 2 that is gaining widespread use in the metastatic breast cancer setting and is undergoing exploration for other oncologic indications. ILD/pneumonitis is an adverse event of special interest associated with T-DXd, which has potentially fatal consequences if left untreated and allowed to progress. When identified in the asymptomatic stage (grade 1), T-DXd-related ILD can be monitored and treated effectively with the possibility of treatment continuation. Delayed diagnosis and/or treatment, however, results in progression to grade 2 or higher toxicity and necessitates immediate and permanent discontinuation of this active agent. Strategies are, therefore, needed to optimize careful monitoring during treatment to ensure patient safety and optimize outcomes. Several guidance documents have been developed regarding strategies for the early identification and management of T-DXd-related ILD, although none have been within the context of the Canadian health care environment. A Canadian multidisciplinary steering committee was, therefore, convened to evaluate existing recommendations and adapt them for application in Canada. A multidisciplinary approach involving collaboration among medical oncologists, radiologists, respirologists, and allied health care professionals is needed to ensure the proactive identification and management of T-DXd-related ILD and DI-ILD associated with other agents with a similar toxicity profile.

Interstitial Lung Disease in Connective Tissue Disease: A Common Lesion With Heterogeneous Mechanisms and Treatment Considerations

Connective tissue disease (CTD) related interstitial lung disease (CTD-ILD) is one of the leading causes of morbidity and mortality of CTD. Clinically, CTD-ILD is highly heterogenous and involves rheumatic immunity and multiple manifestations of respiratory complications affecting the airways, vessels, lung parenchyma, pleura, and respiratory muscles. The major pathological features of CTD are chronic inflammation of blood vessels and connective tissues, which can affect any organ leading to multi-system damage. The human lung is particularly vulnerable to such damage because anatomically it is abundant with collagen and blood vessels. The complex etiology of CTD-ILD includes genetic risks, epigenetic changes, and dysregulated immunity, which interact leading to disease under various ill-defined environmental triggers. CTD-ILD exhibits a broad spectra of clinical manifestations: from asymptomatic to severe dyspnea; from single-organ respiratory system involvement to multi-organ involvement. The disease course is also featured by remissions and relapses. It can range from stability or slow progression over several years to rapid deterioration. It can also present clinically as highly progressive from the initial onset of disease. Currently, the diagnosis of CTD-ILD is primarily based on distinct pathology subtype(s), imaging, as well as related CTD and autoantibodies profiles. Meticulous comprehensive clinical and laboratory assessment to improve the diagnostic process and management strategies are much needed. In this review, we focus on examining the pathogenesis of CTD-ILD with respect to genetics, environmental factors, and immunological factors. We also discuss the current state of knowledge and elaborate on the clinical characteristics of CTD-ILD, distinct pathohistological subtypes, imaging features, and related autoantibodies. Furthermore, we comment on the identification of high-risk patients and address how to stratify patients for precision medicine management approaches.

Epidemiology and Risk Factors for Severe Delayed Drug Hypersensitivity Reactions

Severe delayed drug hypersensitivity reactions comprise different clinical entities and can involve different immune-mediated mechanisms. Common examples are severe cutaneous adverse reactions and druginduced internal organ injuries. The incidence of such reactions is overall low but seems to be on the rise reaching numbers as high as 9 per million individuals-years in the case of SJS/TEN and DRESS. Such conditions carry an important associated morbidity, and mortality can attain 40% in SJS/TEN patients, making these hypersensitivity reactions important targets when implementing preventive measures. Several risk factors have been identified for reaction severity; some are transverse, such as older age and underlying chronic diseases. The recent advances in pharmacogenetics allowed the identification of specific populations with higher risk and permitted strategic avoidance of certain drugs being HLA-B*57:01 screening in patients initiating abacavir the best successful example. In this work, we reviewed the epidemiology of SCARs and liver/kidney/lung drug-induced immune-mediated reactions. We focus on particular aspects such as prevalence and incidence, drugs involved, mortality and risk factors.

[Drug-induced interstitial lung disease: approaches to diagnostics and treatment]

Drug-induced interstitial lung disease (D-ILD) can be caused by various drugs, including antibiotics, amiodarone, antitumor, rheumatological and non-steroidal anti-inflammatory drugs. D-ILD includes hypersensitivity reactions, organizing and non-specific interstitial pneumonia, eosinophilic lung diseases, diffuse alveolar damage and alveolar hypoventilation. To exclude other causes of pulmonary diseases, an assessment of the medical history, physical data and examination results, which may include chest X-ray/multispiral computed tomography (MSCT), lung function tests, and bronchoscopy with bronchoalveolar lavage, are necessary. Diagnosis of D-ILD is difficult due to the heterogeneity of clinical, radiological and histological data. The X-ray pathological phenotype of D-ILD is different; a specific MSCT pattern has not been identified. Treatment includes drug withdrawal and, in some cases, glucocorticoid therapy, although there are no prospective studies on their effect on the outcome of the disease. This article provides various drugs that cause ILD, approaches to their diagnosis and treatment.

The role of Chinese herbal medicine in the management of adverse drug reactions of leflunomide in treating rheumatoid arthritis

BACKGROUND

The high discontinuation rate in RA patients who use LEF might be attributed to their intolerance rather than irresponsibility. The concomitant administration of Leflunomide (LEF) with Chinese herbal medicine (CHM) provides a potential solution to preventing the adverse drug reactions (ADRs) induced by LEF during the treatment of rheumatoid arthritis (RA).

PURPOSE

To investigate whether co-administration of LEF with CHM could bring in both increased therapeutic outcomes and reduced ADRs due to the framework of treatment at the level of entire body.

STUDY DESIGN

The mechanism of LEF in RA treatment and the ADRs it induced was introduced based on recent papers. Reported clinical examples of CHM concurrent use with LEF was revealed to provide more evidence. The management of the ADRs caused by LEF was suggested by current researches on the concomitant therapy of CHM with LEF.

RESULTS

The active ingredients, compounds and medicinal herbs all demonstrated properties in relieving toxicities and reducing ADRs when used with LEF and reported in several clinical cases. The wide application of concurrent use of CHM with LEF is however hindered by the complex pathogenesis of RA which requires further scientific grounds for diagnosis and treatment.

CONCLUSION

This review introduced that the adoption of CHM is emerging as a novel strategy for the management of ADRs caused by LEF.

Growing evidence of the safety of JAK inhibitors in patients with rheumatoid arthritis

To facitinib and baricitinib are two of the currently available Janus kinase (JAK) inhibitors for the treatment of patients with RA. Randomized controlled trials have shown that these JAK inhibitors are as efficacious as biological DMARDs. Safety profiles of these JAK inhibitors in randomized controlled trials and their long-term extension studies have been demonstrated; however, real world evidence remains to be established to bridge the gap between randomized controlled trials and rheumatology clinics. Fundamentally, no difference in the screening, prevention, and monitoring of infections between JAK inhibitors and biological DMARDs exists. However, increased risk of herpes zoster is probably common to all JAK inhibitors. No indication of increased risk for malignancy in patients with RA treated with JAK inhibitors has been reported. To evaluate risks of relatively rare serious adverse events such as thromboembolic events, gastrointestinal perforation, and interstitial lung disease in clinical settings, accumulation of cases with these events are needed. Continuous pharmacovigilance activity is absolutely warranted to establish the safety of JAK inhibitors in patients with RA and other rheumatic diseases.

Drug-Induced Interstitial Lung Disease: A Systematic Review

Background: Drug-induced interstitial lung disease (DIILD) occurs as a result of numerous agents, but the risk often only becomes apparent after the marketing authorisation of such agents. Methods: In this PRISMA-compliant systematic review, we aimed to evaluate and synthesise the current literature on DIILD. Results: Following a quality assessment, 156 full-text papers describing more than 6000 DIILD cases were included in the review. However, the majority of the papers were of low or very low quality in relation to the review question (78%). Thus, it was not possible to perform a meta-analysis, and descriptive review was undertaken instead. DIILD incidence rates varied between 4.1 and 12.4 cases/million/year. DIILD accounted for 3–5% of prevalent ILD cases. Cancer drugs, followed by rheumatology drugs, amiodarone and antibiotics, were the most common causes of DIILD. The radiopathological phenotype of DIILD varied between and within agents, and no typical radiological pattern specific to DIILD was identified. Mortality rates of over 50% were reported in some studies. Severity at presentation was the most reliable predictor of mortality. Glucocorticoids (GCs) were commonly used to treat DIILD, but no prospective studies examined their effect on outcome. Conclusions: Overall high-quality evidence in DIILD is lacking, and the current review will inform larger prospective studies to investigate the diagnosis and management of DIILD.

Management of the Rheumatoid Arthritis Patient with Interstitial Lung Disease

The treatment of rheumatoid arthritis (RA) has undergone considerable changes over the last 15–20 years. With an expansion in the armamentarium of therapies available for RA comes a wider choice in selecting the best treatment in terms of comparative safety in the presence of comorbidities. Clinicians frequently encounter patients with RA-associated interstitial lung disease with uncontrolled joint disease and have to make decisions about the safest treatments in this context with the eventual goal of joint remission. In this chapter, available evidence is reviewed on the comparative pulmonary safety of non-biologic disease-modifying antirheumatic drugs (nbDMARDs), biologic DMARDs, biosimilars and targeted synthetic DMARDs in RA-ILD. In addition, the potential role for additional immunosuppression in RA-ILD is reviewed as well as overarching recommendations proposed for patient assessment to guide treatment decisions and management.

Diffuse alveolar damage in a patient with rheumatoid arthritis under prolonged leflunomide treatment: A Case Report and Literature Review

Patients with rheumatoid arthritis (RA) often have pulmonary involvement, and interstitial lung disease (ILD) is the primary manifestation, in which diffuse alveolar damage (DAD) is a rare histopathologic pattern. Leflunomide (LEF) is a frequently prescribed disease-modifying antirheumatic drug for treating RA. LEF-related ILD in the form of DAD has been reported in patients with RA, with the duration of LEF treatment before symptom onset ranging from 6 to 1204 days.We present a case of elderly woman with RA under prolonged LEF treatment for >9 years (3291 days), who had acute respiratory failure with the initial presentation of exertional dyspnea, fever, chills, and productive cough for 2 days. The histopathologic result of surgical lung biopsy was compatible with DAD. She was diagnosed as having LEF-related ILD, based on correlated clinical history, compatible histopathologic examination and excluding possible infection after extensive survey.Although the causative role of LEF cannot be confirmed, this case still hints that LEF-related DAD may occur even if LEF has been prescribed for a prolonged period.

Interstitial lung disease in rheumatoid arthritis: Current concepts in pathogenesis, diagnosis and therapeutics

Rheumatoid arthritis (RA) is the most common chronic autoimmune inflammatory joint disease. RA-associated interstitial lung disease (RA-ILD) is a major extra-articular complication and causes symptoms that lead to a deterioration in the quality of life, high utilization of health resources, and an increased risk of earlier mortality. Early in the course of RA-ILD, symptoms are highly variable, making the diagnosis difficult. Therefore, a rational diagnostic strategy that combines an adequate clinical assessment with the appropriate use of clinical tests, including pulmonary function tests and high-resolution computed tomography, should be used. In special cases, lung biopsy or bronchioalveolar lavage should be performed to achieve an early diagnosis. Several distinct histopathological subtypes of RA-ILD are currently recognized. These subtypes also have different clinical presentations, which vary in therapeutic response and prognosis. This article reviews current evidence about the epidemiology of RA-ILD and discusses the varying prevalence rates observed in different studies. Additionally, aspects of RA-ILD pathogenesis, including the role of cytokines and other molecules such as autoantibodies, as well as the evidence linking several drugs used to treat RA with lung damage will be discussed. Some aspects of the clinical characteristics of RA-ILD are noted, and diagnostic strategies are reviewed. Finally, this article analyzes current treatments for RA-ILD, including immunosuppressive therapies and biologic agents, as well as other therapeutic modalities. The prognosis of this severe complication of RA is discussed. Additionally, this paper examines updated evidence from studies identifying an association between drugs used for the treatment of RA and the development of ILD.

Comparison of phenotype and outcome in microscopic polyangiitis between Europe and Japan

OBJECTIVE

There are differences between Europe and Japan in the incidence and antineutrophil cytoplasmic antibody (ANCA) serotype of patients with microscopic polyangiitis (MPA). However, differences in phenotype or outcome have not been explored. We aimed to identify differences in phenotype and outcome of MPA between Europe and Japan.

METHODS

Sequential cohorts of patients with MPA and renal limited vasculitis were collected from European and Japanese centers (n = 147 and n = 312, respectively). Trial databases from the European Vasculitis Society and the Japanese patients with Myeloperoxidase (MPO)-ANCA-Associated Vasculitis (JMAAV) trial were studied (n = 254 and n = 48, respectively). We evaluated baseline characteristics including ANCA status and organ involvement, treatment, survival, and renal survival. Differences in survival and renal survival were studied using multivariate analysis.

RESULTS

The non-trial cohorts showed patients with MPA in Japan had a higher age at onset, more frequent MPO-ANCA positivity, lower serum creatinine, and more frequent interstitial pneumonitis than those in Europe (all p < 0.01). Comparisons between the trial databases demonstrated similar results. Cumulative patient survival and renal survival rates were not different between Europe and Japan (p = 0.71 and p = 0.38, respectively). Multivariate analysis identified age at onset, serum creatinine, gastrointestinal, and respiratory involvement as factors with higher risk of death. For endstage renal failure, serum creatinine and use of plasma exchange were identified as factors with higher risk, and immunosuppressant use as lower risk factors.

CONCLUSION

Phenotypes in patients with MPA were different between Europe and Japan. However, the outcomes of patient survival and renal survival were similar.

Interstitial lung diseases induced or exacerbated by DMARDS and biologic agents in rheumatoid arthritis: a systematic literature review

OBJECTIVE

To review published cases of induced or exacerbated interstitial lung disease (ILD) in rheumatoid arthritis (RA) associated with non-biologic disease-modifying antirheumatic drugs (nbDMARDs) and biologics and to discuss clinical implications in daily practice.

METHODS

We performed a systematic literature review from 1975 to July 2013 using Medline, Embase, Cochrane, and abstracts from the ACR 2010-2012 and EULAR 2010-2013 annual meetings. Case reports and series that suggest a causative role of nbDMARDs (methotrexate [MTX], leflunomide [LEF], gold, azathioprine [AZA], sulfasalazine [SSZ], and hydroxychloroquine [HCQ]) and biologic agents (TNF inhibitors [TNFi], rituximab [RTX], tocilizumab [TCZ], abatacept [ABA], and anakinra) in causing ILD or worsening a pre-existing ILD in RA patients were included. Results from observational and postmarketing studies as well as reviews on this topic were excluded from the qualitative analysis but still considered to discuss the implication of such drugs in generating or worsening ILD in RA patients. Comparisons were made between MTX-induced ILD in RA and the cases reported with other agents, in terms of clinical presentation, radiological features, and therapeutic management and outcomes.

RESULTS

The literature search identified 32 articles for MTX, 12 for LEF (resulting in 34 case reports), 3 for gold, 1 for AZA, 4 for SSZ, 27 for TNFi (resulting in 31 case reports), 3 for RTX, 5 for TCZ (resulting in 8 case reports), and 1 for ABA. No case was found for HCQ or anakinra. Common points are noted between LEF- and TNFi-related ILD in RA: ILD is a rare severe adverse event, mostly occurs within the first 20 weeks after initiation of therapy, causes dyspnea mostly in older patients, and can be fatal. Although no definitive causative relationship can be drawn from case reports and observational studies, these data argue for a pulmonary follow-up in RA patients with pre-existing ILD, while receiving biologic therapy or nbDMARDs.

CONCLUSION

As previously described for MTX, growing evidence highlights that LEF, TNFi, RTX, and TCZ may induce pneumonitis or worsen RA-related pre-existing ILD. Nonetheless, identifying a causal relationship between RA therapy and ILD-induced toxicity clearly appears difficult, partly because it is a rare condition.

Long-term therapeutic effects and safety of tacrolimus added to methotrexate in patients with rheumatoid arthritis

To assess the long-term safety and efficacy of tacrolimus (TAC) used in combination with oral methotrexate (MTX) in patients with rheumatoid arthritis (RA) whose disease remains active despite treatment with MTX alone. The clinical courses of 24 RA patients who received TAC added to MTX from a single center were analyzed retrospectively. The disease activity was evaluated by the DAS28-ESR(3) every 12 months after the addition of TAC, and side effects were evaluated for 3 years. At 3 years after starting the treatment, TAC was still being used by 19 patients (79 %). The causes of discontinuation were an inadequate response (3 cases), oral ulcers and elevation of creatinine (1 case), and worsening of interstitial pneumonia (1 case). No death was registered. The DAS28-ESR(3) was decreased from 4.81 to 3.41 after 3 years of treatment. The doses of prednisolone were decreased from 5.1 mg/day to 3.2 mg/day after 3 years. In patients whose active RA persists despite treatment with MTX, TAC in combination with MTX is safe and well tolerated and provided clinical benefit for a long time in this single-center retrospective study. Further studies are required to confirm the safety and efficacy of this combination therapy.

Risk factors of severe infections in patients with rheumatoid arthritis treated with leflunomide

OBJECTIVES

To determine the risk of severe infection requiring or complicating hospitalization associated with leflunomide therapy in patients with rheumatoid arthritis (RA).

METHODS

We performed a retrospective study of RA patients who were prescribed leflunomide between 2004 and 2011. Background clinical and laboratory features were compared between patients who suffered severe leflunomide-associated infections and those who did not.

RESULTS

Since January 2005, 401 RA patients have started on leflunomide. Among those, 33 (8.2%) developed severe infections: pneumonia, oral candidiasis, pyelonephritis, pulmonary tuberculosis, cellulitis, disseminated herpes zoster, tonsillitis, and pulmonary cryptococcosis. Logistic regression showed that age at entry, the presence of DM, and daily dosage of corticosteroid were associated with development of severe infections.

CONCLUSIONS

These results showed that some patients with RA who were taking leflunomide developed severe infections requiring hospitalization, and that older age, DM, and a higher daily dosage of corticosteroid were risk factors associated with leflunomide-associated severe infections.

Leflunomide-induced interstitial pneumonitis might be a representative of disease-modifying antirheumatic drug-induced lung injury

INTRODUCTION

Although disease-modifying antirheumatic drugs (DMARDs) are crucial for rheumatoid arthritis (RA) therapy, they have severe adverse events including interstitial pneumonitis (IP). DMARD-induced IP attracts attention because of its relatively high prevalence, occasionally fatal outcome and clinical features which are common to the IP caused by different DMARDs.

AREAS COVERED

Immediately after the introduction of leflunomide (LEF) in Japan in 2003, IP frequently developed under its use and cases with a fatal outcome were reported. The data obtained by a registration system for all patients who were prescribed LEF are examined, and the features are compared to those of other DMARD-induced IP. The features included acute respiratory distress with severe inflammatory reaction; ground-glass opacities and/or consolidations in the upper, anterior and central lung fields on XP/CT; peripheral blood lymphopenia; and diffuse alveolar damage confirmed in autopsied cases. The most outstanding risk for LEF-induced lung injury was pre-existing IP with an odds ratio of 8.17. A good response to LEF in terms of arthritis remission was suggested. Similar cases have been reported in countries other than Japan, although fewer cases were in Western countries.

EXPERT OPINION

LEF use should be avoided at least for Japanese RA patients with pre-existing IP. The pathogenesis of DMARD-induced lung injury may have common features that need to be clarified in the future.

Reappraisal of the clinical use of leflunomide in rheumatoid arthritis and psoriatic arthritis

Leflunomide is a disease-modifying antirheumatic drug (DMARD) that has been in routine clinical use for the treatment of rheumatoid arthritis (RA) and psoriatic arthritis for a decade. In RA, clinical trials of up to two years' duration showed that leflunomide monotherapy was equivalent to methotrexate in clinical and radiographic disease outcomes (tender and swollen joint counts, physician and patient global assessments, American College of Rheumatology and Disease Activity Score responses, slowing or halting of radiographic progression). In a number of studies, quality of life measurements indicated that leflunomide is superior to methotrexate. Leflunomide has been studied in combination with methotrexate and shows efficacy in patients only partly responsive to this agent. Recent trials have shown that leflunomide can be used safely with biologic DMARDs, including antitumor necrosis factor agents and rituximab as part of the treatment algorithm in place of methotrexate as a cotherapy. Leflunomide has demonstrated efficacy as a monotherapy in psoriatic arthritis, and it also has a beneficial effect in psoriasis. Postmarketing studies have shown that retention on treatment with leflunomide is equal to methotrexate and superior to other DMARDs. In general, its side effect profile is acceptable compared with other DMARDS, with nausea, diarrhea, and hair fall occurring commonly, but only rarely leading to discontinuation. Liver toxicity is the most significant problem in clinical use although it is uncommon. Peripheral neuropathy, hypertension, pneumonitis, and cytopenia occur more rarely. Leflunomide is contraindicated in pregnancy and should be used with caution in women during child-bearing years. In this review, the place of leflunomide in therapy is discussed and practical advice informed by evidence is given regarding dosing regimens, safety monitoring, and managing side effects. Leflunomide remains one of the most useful of the nonbiologic DMARDs.