Rituximab as maintenance therapy for ANCA-associated vasculitides: pooled analysis and long-term outcome of 277 patients included in the MAINRITSAN trials.

OBJECTIVE: To compare the long-term efficacy and safety of azathioprine (AZA), 18-month fixed-schedule rituximab (RTX), 18-month tailored RTX and 36-month RTX in preventing relapses in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis who achieved a complete remission after induction therapy. Patients treated with 36-month RTX received either a fixed or a tailored regimen for the first 18 months and a fixed regimen for the last 18 months (36-month fixed/fixed RTX and 36-month tailored/fixed RTX, respectively). METHODS: The Maintenance of Remission using Rituximab in Systemic ANCA-associated Vasculitis (MAINRITSAN) trials sequentially compared: 18-month fixed-schedule RTX versus AZA (MAINRITSAN); 18-month fixed-schedule RTX versus 18-month tailored-RTX (MAINRITSAN2); and extended therapy to 36 months with four additional RTX infusions after MAINRITSAN2 versus placebo (MAINRITSAN3). Patients were then followed prospectively through month 84 and their data were pooled to analyse relapses and adverse events. The primary endpoint was relapse-free survival at month 84. RESULTS: 277 patients were enrolled and divided in 5 groups: AZA (n=58), 18-month fixed-schedule RTX (n=97), 18-month tailored-RTX (n=40), 36-month tailored/fixed RTX (n=42), 36-month fixed/fixed RTX (n=41). After adjustment for prognostic factors, 18-month fixed-schedule RTX was superior to AZA in preventing major relapses at month 84 (HR 0.38, 95% CI 0.20 to 0.71). The 18-month tailored-RTX regimen was associated with an increased risk of major relapse compared with fixed-schedule regimen (HR 2.92, 95% CI 1.43 to 5.96). The risk of major relapse was similar between 36-month fixed/fixed and 18-month fixed-RTX (HR 0.69, 95% CI 0.38 to 1.25). CONCLUSIONS: According to these results, it appears that the 84-month remission rate is higher with an 18-month fixed RTX regimen compared with AZA and 18-month tailored RTX. Also, extending RTX to 36 months does not appear to reduce the long-term relapse rate compared with the 18-month fixed RTX regimen. However, as this study was underpowered to make this comparison, further prospective studies are needed to determine the potential long-term benefits of extending treatment in these patients.

The temporary use of thrombopoietin-receptor agonists may induce a prolonged remission in adult chronic immune thrombocytopenia. Results of a French observational study.

Thrombopoietin-receptor agonists (Tpo-RAs) are highly effective in immune thrombocytopenia (ITP). Recently, cases of durable remission after Tpo-RA discontinuation in adult ITP have been reported. We aimed to describe the subset of patients in whom transient Tpo-RA therapy may induce a durable response. We studied all adults with primary ITP treated with at least one Tpo-RA over a 5-year period (n = 54) and seen at one of three participating referral centres in France. Tpo-RAs were discontinued in 20 of 28 patients who achieved a complete response. We excluded six patients because a previous treatment at the start of Tpo-RA treatment may have interfered with the response. Overall, eight patients with chronic ITP showed a sustained response [median follow-up: 13·5 months (range 5-27 months)]. We could not identify a predictive factor of sustained response. In conclusion, a substantial proportion of ITP patients receiving Tpo-RAs can maintain a durable response after treatment discontinuation.

PEGylated interferon alfa-2b and ribavirin treatment in patients with hepatitis C virus-related systemic vasculitis.

OBJECTIVE: Type II mixed cryoglobulinemia (MC) is a systemic vasculitis usually associated with hepatitis C virus (HCV), which may involve the skin, kidneys, and nervous system. Molecular evidence of antigen-driven B cell proliferation is definitively provided in HCV-associated type II MC, and HCV appears to be the key trigger. The present trial was established to investigate the efficacy of therapy with PEGylated interferon alfa-2b (PEG-IFN alfa-2b) plus ribavirin in patients with HCV-related MC vasculitis. METHODS: Nine consecutive patients with HCV-related MC received PEG-IFN alfa-2b (1.5 microg/kg/week) subcutaneously plus oral ribavirin (800-1,200 mg/day) for at least 6 months. The response to treatment was analyzed by comparing clinical, immunologic, and virologic parameters at the initial evaluation with those observed during followup. RESULTS: The mean +/- SD duration of therapy with PEG-IFN alfa-2b plus ribavirin was 13.5 +/- 2.8 months. After a mean period of 18.6 months following discontinuation of treatment, all 9 patients are alive. Seven patients (78%) had a sustained virologic response and were complete clinical responders. Serum cryoglobulin disappeared in 5 of 9 patients (56%), and complement levels normalized in 80% of the patients. One patient had a partial virologic response with a complete clinical response. In another patient, a clinical relapse of MC vasculitis occurred in association with the reappearance of HCV RNA. Treatment was well tolerated, and no patient had side effects for which discontinuation of therapy was required. CONCLUSION: Treatment with PEG-IFN alfa-2b plus ribavirin can achieve a complete clinical response in most patients with HCV-related MC vasculitis. Complete clinical response correlates with the eradication of HCV and requires a shorter treatment period than that previously reported for IFNalpha plus ribavirin.