Background Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) affecting individuals older than 50 years and corticosteroids are the mainstay of treatment. Azathioprine and methotrexate have shown little or moderate efficacy as corticosteroid-sparing agents .
Objectives Our aim was to examine the role of leflunomide as a corticosteroid-sparing agent in difficult -to-treat GCA and PMR patients.
Methods Patients with difficult-to-treat GCA and PMR were retrospectively identified in our vasculitis clinic between 2010 and 2013. The dose of corticosteroids and CRP values were recorded before and at the end of the treatment (for patients continuing treatment, censoring date was 1 January 2013). Side-effects were also registered. Student’s t-test was used to compare the means. Statistical significance was defined as p<0.05.
Results Twenty three patients were recruited (3 males, 20 females, mean age 69 years), 12 with PMR and 11 with GCA. All the patients fulfilled either the ACR classification criteria for GCA  or the EULAR/ACR classification criteria for PMR . Mean duration of treatment was 10.7 months (SD 9.8). The mean value of CRP at starting point was 21.8 mg/dl (SD 27.3) and 18.8 mg/dl (SD 18.0) for the PMR and GCA groups respectively. Mean staring dose of corticosteroids was 10.6 mg (SD 4.3) and 10.5 mg (SD 4.2) for PMR and GCA groups respectively. Six patients (26%) discontinued treatment due to side-effects and 5 patients (21%) due to remission. A mean difference of 11.6 mg/dl in CRP (CI 95% -10.9-34.2, p=0.27) and 3.8 mg (CI 95% 0.5-7.0, p=0.03) in prednisolone dose was observed in PMR group. In GCA patients, the mean differences were 12.4 mg/dl (CI 95% -0.7-25.5, p=0.06) in CRP and 6.6 mg (CI 95% 2.8-10.3, p=0.003) in prednisolone dose.
Conclusions Leflunomide seems to be effective as a corticosteroid sparing agent in patients with difficult-to-treat GCA and PMR. However, a high rate of withdrawals was observed in our study, with 1 in 4 patients discontinuing leflunomide treatment due to side-effects. Randomized controlled trials are warranted to examine the usefulness of leflunomide in the treatment of GCA/ PMR.
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Dasgupta B, Cimmino MA, Kremers HM, et al. 2012 Provisional classification criteria for polymyalgia rheumatica: a European League Against Rheumatism/American College of Rheumatology collaborative initiative. Arthritis Rheum. 2012;64(4):943-54. Epub 2012/03/06.
Disclosure of Interest: None Declared