Efficacy of leflunomide as a steroid‐sparing agent in treatment of Indian giant cell arteritis patients: A 2‐year follow‐up study

Updates in the Management of Giant Cell Arteritis

PURPOSE OF THE REVIEW

To briefly review the latest updates in management in giant cell arteritis, an autoimmune vasculitis affecting the medium to large vessels.

RECENT FINDINGS

Here, we review the known and newer trends in management of giant cell arteritis. While high dose glucocorticoids remain the mainstay of therapy, immunosuppressive medications are increasingly utilized to reduce the burden and risk of long-term glucocorticoid use. Published guidelines by the American College of Rheumatology (ACR) and European League Against Rheumatism (EULAR) suggest early use of steroid-sparing immunosuppressive medications in patients with recently diagnosed or relapsing giant cell arteritis. Immunosuppressive medications include oral small molecules such as methotrexate and leflunomide and biologics, including the recently Federal Drug Administration (FDA) approved tocilizumab. Glucocorticoids remain the cornerstone of management for newly diagnosed disease but with the increasing use of medications such as IL-6 inhibitors, patients are decreasing steroid use within weeks, thereby limiting risks associated with long-term steroid use.

Disease stratification in GCA and PMR: state of the art and future perspectives

Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are closely related conditions characterized by systemic inflammation, a predominant IL-6 signature, an excellent response to glucocorticoids, a tendency to a chronic and relapsing course, and older age of the affected population. This Review highlights the emerging view that these diseases should be approached as linked conditions, unified under the term GCA-PMR spectrum disease (GPSD). In addition, GCA and PMR should be seen as non-monolithic conditions, with different risks of developing acute ischaemic complications and chronic vascular and tissue damage, different responses to available therapies and disparate relapse rates. A comprehensive stratification strategy for GPSD, guided by clinical findings, imaging and laboratory data, facilitates appropriate therapy and cost-effective use of health-economic resources. Patients presenting with predominant cranial symptoms and vascular involvement, who usually have a borderline elevation of inflammatory markers, are at an increased risk of sight loss in early disease but have fewer relapses in the long term, whereas the opposite is observed in patients with predominant large-vessel vasculitis. How the involvement of peripheral joint structures affects disease outcomes remains uncertain and understudied. In the future, all cases of new-onset GPSD should undergo early disease stratification, with their management adapted accordingly.

Efficacy and safety of leflunomide in the management of large vessel vasculitis: A systematic review and metaanalysis of cohort studies

OBJECTIVE

The search for new glucocorticoid-sparing disease-modifying anti-rheumatic drugs continues to be an unmet need in large vessel vasculitis (LVV). This report aims to assess the effectiveness and safety of leflunomide (LEF) in Takayasu arteritis (TA) and giant cell arteritis (GCA).

METHODS

We systematically reviewed the literature, searching for studies evaluating the efficacy of LEF in LVV. A meta-analysis was conducted using the random-effects method.

RESULTS

The literature search identified eight studies that assessed LEF in TAK and seven in GCA. All were uncontrolled observational studies with a high risk of bias, implying a low or very-low certainty of evidence. In TAK, the pooled proportion of patients achieving at least a partial remission was 75% (95% CI: 0.64-0.84), angiographic stabilization was observed in 86% (0.77-0.94) and relapses in 12% (0.05-0.21). The mean reduction in the prednisolone dose (MRPD) after LEF treatment was 15.7 mg/d (10.28-21.16). Adverse events were observed in 8% of patients (0.02-0.16). Comparison of LEF with methotrexate (MTX) or cyclophosphamide revealed LEF to be superior in terms of remission induction, relapse prevention, and tolerance. When compared with tofacitinib, both drugs demonstrated comparable efficacy. In GCA, the pooled proportion of patients achieving at least a partial remission was 60% (0.17-0.95). The MRPD after LEF treatment was 15.63 mg/d (1.29-32.55) and 53% of the patients were able to discontinue glucocorticoids (0.25 - 0.80). Relapses were observed in 21% of cases (0.14- 0.28) and adverse events in 28% (0.12-0.46). Comparison of LEF with MTX showed similar efficacy and tolerance.

CONCLUSION

LEF is well tolerated and might be effective for patients with TAK and GCA.

Recent advances in the treatment of giant cell arteritis

Giant cell arteritis (GCA) is a systemic, granulomatous, large-vessel vasculitis that affects individuals over the age of 50 years. Morbidity from disease includes cranial manifestations which can cause irreversible blindness, while extra-cranial manifestations can cause vascular damage with large-artery stenosis, occlusions, aortitis, aneurysms, and dissections. Glucocorticoids while efficacious are associated with significant adverse effects. Furthermore, despite treatment with glucocorticoids, relapses are common. An understanding of the pathogenesis of GCA has led to the discovery of tocilizumab as an efficacious steroid-sparing therapy while additional therapeutic targets affecting different inflammatory pathways are under investigation. Surgical treatment may be indicated in cases of refractory ischemia or aortic complications but data on surgical outcomes are limited. Despite the recent advances, many unmet needs exist, including the identification of patients or subsets of GCA who would benefit from earlier initiation of adjunctive therapies, patients who may warrant long-term immunosuppression and medications that sustain permanent remission. The impact of medications like tocilizumab on long-term outcomes, including the development of aortic aneurysms and vascular damage also warrants investigation.

Effect of Leflunomide Use on 68Ga-DOTATATE Biodistribution in a Case With Neuroendocrine Tumor

ABSTRACT

A 58-year-old man who underwent surgery for a well-differentiated neuroendocrine tumor of pancreatic origin was evaluated with 68Ga-DOTATATE PET/CT imaging in the follow-up period. After PET/CT findings consistent with disease remission, the patient was started on leflunomide treatment with the diagnosis of rheumatoid arthritis. The patient received leflunomide for 6 months. Then, 68Ga-DOTATATE PET/CT scan was repeated to evaluate the primary disease outcome. Besides the disease remission, we also observed alterations in DOTATATE uptakes of some tissues and organs. In this case, we present the changes in 68Ga-DOTATATE PET/CT scan findings after leflunomide use.

Leflunomide: Traditional immunosuppressant with concurrent antiviral effects

Leflunomide is a classic disease-modifying anti-rheumatic drug that is widely used to treat autoimmune diseases. Studies also show its antiviral effects in in vitro and/or in vivo experiments. Considering glucocorticoids, immunosuppressants and newly emerged antibodies commonly used in autoimmune diseases and autoinflammatory disorders bring risk of infection such as viral infection, leflunomide with combination of anti-viral and immunosuppressive features to maintain the balance between infection and anti-inflammation are attractive. Here we summarize the actions and mechanisms of leflunomide in immunoregulatory and antiviral effects.

Performance of leflunomide as a steroid-sparing agent in giant cell arteritis: A single-center, open-label study

BACKGROUND

The management of giant cell arteritis (GCA) remains challenging and many patients require prolonged glucocorticoid treatment due to high disease relapse rates. We aimed to evaluate the role of leflunomide as a steroid-sparing agent in GCA.

METHODS

This prospective open-label study included patients diagnosed with GCA between July 2014 and August 2020 and followed them for 96 weeks. At the time of diagnosis all patients received treatment following a predefined glucocorticoid regimen. At week 12 of follow-up, 10 mg of leflunomide per day was recommended as an adjunctive therapy. The decision to start with leflunomide treatment was patient-dependent. Follow-up visits were performed adhering to a predetermined protocol. The number of relapses, the cumulative glucocorticoid dose and treatment-related adverse events were recorded and compared between glucocorticoid-only and leflunomide groups.

RESULTS

Of the 215 GCA patients [67.6% female, median (IQR) age 74 (66-79) years], 151 (70.2%) received leflunomide at week 12 (leflunomide group); the others continued with glucocorticoids (glucocorticoid-only group). During the study 64/215 (29.8%) patients relapsed. Of the 51 patients who relapsed after 12 weeks, 22/151 patients (14.6%) and 29/64 patients (45.3%) were in the leflunomide and glucocorticoid-only group, respectively (p = 0.001; NNT 3.3 for leflunomide). Furthermore, 80/151 patients in the leflunomide group managed to stop glucocorticoids at week 48 [with relapses in 6/80 patients (7.5%)]. The cumulative glucocorticoid dose was lower in the leflunomide group (p = 0.009).

CONCLUSION

In our cohort, leflunomide safely and effectively reduced the GCA relapse rate and demonstrated a steroid-sparing effect in over three quarters of patients.