ObjectiveTo evaluate the efficacy and safety of subcutaneous (SC) abatacept and standard of care (SOC) for the treatment of idiopathic inflammatory myopathy (IIM) over 52 weeks.MethodsIn this randomised, double‐blind, placebo‐controlled phase III trial, patients with treatment‐refractory IIM received SC abatacept (125 mg weekly) + SOC (abatacept group) or placebo + SOC (placebo group) (NCT02971683). A 24‐week double‐blind period was followed by an open‐label period to assess outcomes from continued therapy with abatacept and initiation with abatacept (placebo‐to‐abatacept switch group) from 24 to 52 weeks. The primary endpoint was International Myositis Assessment and Clinical Studies definition of improvement (IMACS DOI) at week 24. Secondary efficacy and safety endpoints were assessed.ResultsOverall, 148 (double‐blind) and 133 (open‐label) patients were treated. Baseline demographics were well‐balanced between treatment groups and disease subtypes. At 24 weeks, improvement per IMACS DOI was 56.0% for the abatacept group and 42.5% for the placebo group (p=0.083); at 52 weeks, improvement was 69.8% (continued abatacept) and 69.0% (placebo‐to‐abatacept switch). IMACS DOI rate at 24 weeks was greater in the non‐dermatomyositis (DM) group (abatacept: 57.1%; placebo: 32.3%; p=0.040) than the DM group (abatacept: 55.0%; placebo: 50.0%; p=0.679). The observed safety profile was similar in both groups.ConclusionThe proportion of patients who met improvement criteria after 24 weeks was similar between abatacept and placebo groups. However, analysis by IIM subtype suggested there may be sustained benefit of SC abatacept for patients with non‐DM subtypes.

中文翻译：

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皮下注射阿巴西普 + 标准治疗活动性特发性炎症性肌病的疗效和安全性：III 期随机对照试验


目的评价皮下注射 （SC） 阿巴西普和护理标准 （SOC） 治疗特发性炎症性肌病 （IIM） 52 周的疗效和安全性。方法在这项随机、双盲、安慰剂对照的 III 期试验中，难治性 IIM 患者接受 SC 阿巴西普（每周 125 毫克）+ SOC（阿巴西普组）或安慰剂 + SOC（安慰剂组）（NCT02971683）。24 周的双盲期之后是开放标签期，以评估 24 至 52 周继续使用阿巴西普和开始使用阿巴西普 （安慰剂到阿巴西普转换组） 的结果。主要终点是第 24 周时国际肌炎评估和临床研究改善定义 （IMACS DOI）。评估次要疗效和安全性终点。结果总体而言，148 例 （双盲） 和 133 例 （开放标签） 患者接受了治疗。治疗组和疾病亚型之间的基线人口统计学非常平衡。在 24 周时，根据 IMACS DOI ，阿巴西普组改善 56.0%，安慰剂组改善 42.5% （p=0.083）;52 周时，改善为 69.8%（继续使用阿巴西普）和 69.0%（安慰剂转为阿巴西普）。非皮肌炎 （DM） 组（阿巴西普：57.1%;安慰剂：32.3%;p=0.040）在 24 周时的 IMACS DOI 率高于 DM 组（阿巴西普：55.0%;安慰剂：50.0%;p=0.679）。两组观察到的安全性相似。结论阿巴西普组和安慰剂组 24 周后达到改善标准的患者比例相似。然而，按 IIM 亚型进行的分析表明，SC 阿巴西普可能对非 DM 亚型患者有持续的益处。