Ultra-low dose rituximab as add-on therapy in anti-MDA5-positive patients with polymyositis /dermatomyositis associated ILD.

To evaluate the efficacy and safety of ultra-low dose (100 mg) rituximab (RTX) administration in anti-melanoma differentiation-associated gene 5 (MDA5) positive patients with polymyositis/dermatomyositis (PM/DM) associated interstitial lung disease. This retrospective study included anti-MDA5 antibody positive ILD subjects in the First Affiliated Hospital of Guangzhou Medical University from November 2017 to March 2019. Independent predictors for 180-day mortality were measured by Cox regression analysis. Patients were divided into 3 groups: Group 1 (non-cyclophosphamide (CTX)/RTX) (n = 10), Group 2 (CTX only) (n = 19) and Group 3 (RTX with/without CTX) (n = 11). The 180-day mortality was compared among 3 groups with Kaplan-Meier analysis. Post-RTX serological parameters as well as adverse events were evaluated. Forty patients were included with the mean age of 51.3 years. Elevated IL-10 level and CD4+/8+ ratio were considered as risk factors of 180-day mortality. Kaplan-Meier analysis showed a trend toward decrease, albeit non-significant, in 180-day mortality in Group 3 (P = 0.26). The administration of 100 mg RTX brought down B cell within 7 days that lasted for 180 days. There were 7 and 6 infection events observed within 2 months of CTX/RTX treatment in Group 2 and 3, with 5 and 2 fatal cases respectively. Cytomegalovirus infection accounted for half infection events in Group 3. We found a pronounced and prolonged B cell depletion following 100 mg RTX infusion and RTX add-on may be effective in anti-MDA5 positive ILD patients. However, infection, especially opportunistic infection, should be concerned during the treatment.

Mao MM ，Xia S ，Guo BP ，Qian WP ，Zheng ZX ，Peng XM ，Chen RC ，Luo Q ，Han Q ... -  《-》

Comprehensive assessment of myositis-specific autoantibodies in polymyositis/dermatomyositis-associated interstitial lung disease.

Myositis-specific autoantibodies (MSAs) are associated with clinical phenotypes in polymyositis/dermatomyositis (PM/DM). No study has investigated the clinical features based on comprehensive MSA assessment in PM/DM-associated interstitial lung disease (ILD). We aimed to determine the practical significance of MSAs in PM/DM-ILD. Sixty consecutive PM/DM-ILD patients were retrospectively analysed. Serum MSAs were comprehensively measured using immunoprecipitation assay. Clinical features and prognosis were compared among MSA subgroups. Twenty-six (43.3%) PM/DM-ILD patients were anti-aminoacyl tRNA-synthetase antibody-positive (anti-ARS-positive), 15 (25.0%) were anti-melanoma differentiation-associated gene 5 antibody-positive (anti-MDA5-positive), 3 (5%) were anti-signal recognition particle antibody-positive, 1 (1.7%) was anti-transcriptional intermediary factor 1-gamma antibody-positive, and 15 (25%) were MSA-negative. There were significant differences in clinical features, including ILD form, serum ferritin and surfactant protein-D levels at ILD diagnosis, and high-resolution CT pattern among the anti-ARS-positive, anti-MDA5-positive and MSA-negative groups. The anti-MDA5-positive group showed the lowest 90-day survival rate (66.7%, anti-MDA5-positive; 100%, anti-ARS-positive; 100%, MSA-negative; P < 0.01). The anti-ARS-positive group had the highest 5-year survival rate (96%, anti-ARS-positive; 66.7%, anti-MDA5-positive; 68.3%, MSA-negative, P = 0.02). Univariate analysis revealed that anti-ARS antibody was associated with better prognosis (HR = 0.45; 95% CI, 0.18-0.89; P = 0.02), whereas anti-MDA5 antibody was associated with poorer prognosis (HR = 1.90; 95% CI, 1.02-3.39; P = 0.04). The comprehensive MSA assessment demonstrated that anti-ARS and anti-MDA5 antibodies were two major MSAs, and the clinical features differed depending on MSA status in PM/DM-ILD. Assessment of anti-ARS and anti-MDA5 antibodies is practically useful for predicting clinical course and prognosis in PM/DM-ILD patients.

Hozumi H ，Fujisawa T ，Nakashima R ，Johkoh T ，Sumikawa H ，Murakami A ，Enomoto N ，Inui N ，Nakamura Y ，Hosono Y ，Imura Y ，Mimori T ，Suda T ... -  《-》

Anti-melanoma differentiation-associated gene 5 (MDA5) antibody-positive dermatomyositis responds to rituximab therapy.

Ge Y ，Li S ，Tian X ，He L ，Lu X ，Wang G ... -  《-》

Rituximab for refractory rapidly progressive interstitial lung disease related to anti-MDA5 antibody-positive amyopathic dermatomyositis.

So H ，Wong VTL ，Lao VWN ，Pang HT ，Yip RML ... -  《-》

Rituximab in the Treatment of Interstitial Lung Diseases Related to Anti-Melanoma Differentiation-Associated Gene 5 Dermatomyositis: A Systematic Review.

The effectiveness of rituximab in anti-melanoma differentiation-associated gene 5 (MDA5) dermatomyositis (DM) with interstitial lung disease (ILD) has been explored only in isolated case reports and small series. This paper aims to review the current evidence regarding rituximab (RTX) use in the treatment of ILD related to anti-MDA5 DM (anti-MDA5 DM-ILD). We conducted a review by searching PubMed, Web of Science, Embase, and Cochrane for articles with information on patients with anti-MDA5 DM and RTX treatment, published until August 2021, in English language. The selected studies listed variation in chest high-resolution computed tomography (HRCT) and/or pulmonary function test (PFT) as a primary outcome, in patients with anti-MDA5 DM-related ILD after using RTX. Of the 145 potentially eligible articles, 17 were selected. The information gathered from a total of 35 patients with anti-MDA5 DM-ILD was reviewed, including 13 men and 22 women. Patient age at onset was 47.60 ± 13.72 years old. A total of 11.43% (4/35) of the patients were found to have chronic ILD (C-ILD) and 88.57% (31/30) exhibited rapidly progressive ILD (RP-ILD). Most patients (29/30) had typical DM rashes. Prior to RTX administration, the majority of patients (27/35) were treated with medium- or high-dose glucocorticoids and at least one additional immunotherapeutic agent. With regard to RTX efficacy for ILD in anti-MDA5 DM, 71.43% (25/35) of the patients responded to treatment. Skin rash also improved in more than half of the patients after RTX treatment. The most common side effects were infections, reported by 37.14% (13/35) of the patients after using RTX. As a CD20 targeting drug, RTX is a promising therapeutic tool for anti-MDA5 DM-ILD, although the risk of infections should be considered before treatment. Further prospective controlled studies are required to evaluate the optimal RTX treatment regimen. https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021289714, identifier CRD42021289714.

He C ，Li W ，Xie Q ，Yin G ... -  《Frontiers in Immunology》