Comparative study of clinical effects between plasma adsorption and double filtration plasmapheresis in patients with myasthenia gravis

Efficacy and safety of double-filtration plasmapheresis treatment of myasthenia gravis: A systematic review and meta-analysis

OBJECTIVES

To evaluate the efficacy of double-filtration plasmapheresis (DFPP) treatment of myasthenia gravis (MG) through a systematic review and meta-analysis.

METHODS

PubMed, Cochrane Library, Embase, China National Knowledge Infrastructure (CNKI), Chinese Scientific Journals Database (VIP), and Wanfang databases were searched for randomized controlled trials (RCTs) and clinical controlled trials (CCTs) on DFPP for MG from database establishment to June 2019. Two researchers independently screened the articles, extracted the data, and cross checked the results. RevMan 5.3 was used for statistical analyses.

RESULTS

Seven RCTs and 2 CCTs were found comprising 329 patients. The results showed that clinical MG remission rate after DFPP treatment was significantly higher (OR = 4.33; 95% confidence interval [CI], 1.97-9.53; P < .001) and the serum levels of antititin antibody was significantly decreased (standardized mean difference [SMD] = 9.30; 95% CI, 7.51-11.08; P < .001). In addition, the quantitative MG (QMG) score, hospital stay and time to remission of MG symptoms, and acetylcholine receptor antibody (AchRAb) decreased in the DFPP treatment group; however, these outcomes had high heterogeneity among the studies. Only one study has reported on the adverse effects, including hypotension and hematoma.

CONCLUSION

This meta-analysis suggests that DFPP can be recommended for the short-term mitigation of MG. Because our review was limited by the quantity and quality of the included studies, the above conclusions should be verified by additional high-quality studies.

Treatment of refractory myasthenia gravis by double-filtration plasmapheresis and rituximab: A case series of nine patients and literature review

INTRODUCTION

Myasthenia gravis (MG) is an autoimmune disease mediated by circulating autoantibodies (anti-AchR, anti-MuSK, etc.). More than 20% of myasthenic patients are refractory to conventional treatments (plasma exchange, IVIg, steroids, azathioprine, mycophenolate mofetil). Rituximab (B-lymphocyte-depleting anti-CD20) and apheresis (double-filtration plasmapheresis [DFPP] and immunoadsorption [IA]) are interesting therapeutic alternatives.

METHODS

This monocentric pilot study included nine refractory myasthenic patients (March 2018 to May 2020) treated by DFPP and/or IA associated with rituximab (375 mg/m² ). Clinical responses were assessed using the Myasthenia Gravis Foundation of America (MGFA) score.

RESULTS

Average age of patients was 53 ± 17 years. Gender ratio (M/F) was 3:6. The combination of apheresis and rituximab reduced median MGFA score from IV to II after 12 months of follow-up. Clinical improvement assessed by MGFA score was sustained in the long-term for all patients, during an average follow-up of 14 ± 9 months, allowing them to be self-sufficient and out sick-leave. The median number of apheresis sessions was 7 (5-30). The dose of prednisolone was reduced in two patients from 40 mg/d and 30 mg/d to 7.5 mg/d and 10 mg/d, respectively. It was stopped in a patient who was taking 30 mg/d. No infectious, bleeding, or thrombosis complications were noted.

CONCLUSION

The combination of rituximab and DFPP was effective to treat refractory MG.

A Controlled Study of Double Filtration Plasmapheresis in the Treatment of Active Rheumatoid Arthritis

BACKGROUND

Double-filtration plasmapheresis with a plasma fractionator pore size of 20 nm should selectively remove large molecular weight substances like rheumatoid factor and IgM. This was proposed to be more likely to be helpful for rheumatoid arthritis than standard plasma exchange.

OBJECTIVE

To evaluate the efficacy of double-filtration plasmapheresis (DFPP) in the treatment of patients with active rheumatoid arthritis.

METHODS

Eighty-two patients were randomly assigned, 42 to the DFPP group and 40 to the no-DFPP group. All patients received sulfasalazine (0.75 g 3 times daily) plus methotrexate (10 mg orally once weekly). All patients had been on stable doses for more than 3 months. DFPP was performed once a week for 2 to 3 sessions. A total of 121 plasmapheresis procedures were performed in 42 patients. Control patients did not receive sham DFPP. The efficacy measures recorded 1 day after the final treatment and every month in follow-up for 4 to 22 months included the American College of Rheumatology (ACR) 20%, 50%, and 70% improvement criteria (ACR20, ACR50, and ACR70), the Health Assessment Questionnaire estimate of disability and the disease activity index.

RESULTS

Patients in the DFPP group had ACR20, ACR 50, and ACR70 improvements immediately after the last treatment of 100%, 92.9%, and 81.0%, when compared with the patients in no-DFPP group 17.5%, 0%, and 0% (P < 0.001). Significant change from baseline was observed in Health Assessment Questionnaire scores in the DFPP group, but not in the no-DFPP group (P < 0.001). The changes from baseline in the disease activity scores were significantly greater than in the no-DFPP group (P < 0.001). Improvements were maintained during follow-up of 7 to 22 months.

CONCLUSION

This open trial showed that DFPP therapy significantly altered the signs and symptoms of active rheumatoid arthritis. There were increases in physical function and improvement in quality of life. This is proposed as an approach that merits further investigation.

Beneficial effects of plasmapheresis before thymectomy on the outcome in myasthenia gravis

OBJECTIVE

Since 1980, we have performed plasmapheresis before thymectomy for patients with generalized symptoms in order to protect against myasthenic crisis and to improve patient outcomes after thymectomy. The aim of this study was to evaluate an immediate and a long-term results of plasmapheresis before thymectomy for myasthenia gravis, retrospectively.

METHODS

Between January 1980 and December 1997, 51 patients with Osserman class IIA or IIB symptoms were treated with transsternal thymectomy. Nineteen patients (group 1) were treated with plasmapheresis before thymectomy and 32 patients (group 2) were treated with thymectomy alone.

RESULTS

In group 1, the time of plasmapheresis prior to thymectomy was 3.2 +/- 1.5. Nine (28.1%) patients in group 2 had crisis within 1 year after thymectomy as compared with only one (5.3%) patient in group 1 had crisis (p = 0.049). There was no evidence of crisis within 30 days after thymectomy in group 1 and 5 (15.6%) patients in group 2 (p = 0.0724). There was no postoperative death among patients in group 1. Responses to thymectomy in group 1 improved significantly, the improvement and pharmacologic remission rate had increased up to 100% and 79% at 5-7 years after operation, while the improvement and pharmacologic remission rate of group 2 had increased to 81.3% (p = 0.0466 vs. group 1) and 50.0% at that time (p = 0.0427 vs. group 1).

CONCLUSIONS

The present study demonstrated that preoperative plasmapheresis may facilitate improved outcomes of patients with myasthenia gravis after thymectomy.

Membranes for therapeutic apheresis

Kuraray has developed many kinds of apheresis devices, such as plasma separators, plasma fractionators, and apheresis monitors. In this article, apheresis membranes, especially double filtration plasmapheresis (DFPP) and plasma fractionators used in DFPP are introduced. DFPP is both clinically and cost effective apheresis therapy, and it has been used widely for the treatment of many kinds of diseases. Several types of plasma separators with various pore sizes are available. It is important to select the proper plasma separator with suitable pore size, determined by the size of the pathogenic substances to be removed. The Evaflux 5A ethylene-vinyl alcohol copolymer plasma fractionator efficiently separates low-density lipoprotein from high-density lipoprotein. DFPP with the Evaflux 5A is effective for the treatment of familiar hyperlipidemia.

The six year experience of plasmapheresis in patients with myasthenia gravis

Plasmapheresis (PP) effectively removes autoantibodies in various autoimmune diseases. The use of PP in the treatment of myasthenia gravis (MG) has been widely accepted since the 1970s. The treatment protocol, however, has not been standardized. For the last 6 years, we collected a total of 94 MG patients, 38 males and 56 females aged 14-80 years, who received 175 courses of PP treatment for a total of 823 sessions. The methods we used were double filtration plasmapheresis (DF), immunoadsorption plasmapheresis (IA), and plasma exchange (PE). There were 167 courses of DF, 6 courses of IA, and 2 courses of PE. Each course of treatment consists of 4 to 5 sessions of apheresis. The processed volume of plasma is 1 calculated plasma volume. All patients tolerated PP well although 2.3% of them experienced hypotension. Our experiences are summarized as follows. Both DF and IA effectively ameliorate symptoms and signs of MG. IA removes acetylcholine receptor antibody more effectively than DF does, but clinical effects between these 2 methods are similar. A daily schedule seems more effective than an alternate daily schedule. The optimal number of PP sessions for each course is 4. The factors correlating with better clinical response are high MG score, nonthymoma patients, younger age at onset, and higher removal rate for immunoglobulin G.

Double filtration plasmapheresis in myasthenia gravis--analysis of clinical efficacy and prognostic parameters

OBJECTIVES

The aim of this study was to evaluate the efficacy of double filtration plasmapheresis (DFP) in the treatment of patients with myasthenia gravis (MG) and to analyze the possible prognostic factors related to responsiveness to DFP.

MATERIALS AND METHODS

We treated 45 MG patients, 26 women and 19 men aged 21-72 years, with DFP for 5 consecutive sessions. All were affected by severe generalized or respiratory weakness with an Osserman's classification of group 2 or 3 and had not responded to previous treatments.

RESULTS

Thirty-eight out of 45 patients (84%) achieved significant improvements after DFP. The baseline MG score and removal rate for immunoglobulin G (IgG) were significantly higher in the patients with good response than in the other response groups. Poor responders were more likely to have thymoma and a longer interval among sessions of DFP. Better response in patients with age at onset of less than 40 years was associated with higher MG score. Serum concentration of all proteins tested fell as follows (mean +/- SD): IgM, 88+/-7%; IgA, 71+/-11%; IgG, 59+/-14%; globulin, 52+/-11%; AchRAb, 47+/-14%; and albumin, 27+/-10%. All the patients tolerated plasmapheresis well except for 2.2% who experienced hypotension.

CONCLUSION

In this study, DFP was effective and safe in the treatment of patients with severe generalized MG. The factors correlating with the better clinical response were high MG score, a thymic pathology of non-thymoma, daily apheresis, young age at onset, and high removal rate for IgG.