Late onset Pompe disease (LOPD) is a genetic disorder characterized by slowly progressive skeletal and respiratory muscle weakness. Symptomatic patients are treated with enzyme replacement therapy (ERT) with alglucosidase alpha (rhGAA). Although most of ERT treated patients develop antibodies against rhGAA, their influence on clinical progression is not completely known. We studied the impact of anti-rhGAA antibodies on clinical progression of 25 ERT treated patients. We evaluated patients at visit 0 and, after 1 year, at visit 1. We performed several muscle function tests, conventional spirometry and quantitative muscle MRI (qMRI) using 3-point Dixon analysis of thigh muscles at both visits. We also obtained serum samples at both visits and anti-rhGAA antibodies were quantified using ELISA. Antibody titers higher than 1:200 were identified in 18 patients (72%) of our cohort. Seven patients (28%) did not develop antibodies (0 to <1:200), 17 patients (68%) developed low to intermediate titers (1:200 to <1:31,200) and 1 patient (4%) developed high titers (>1:31,200). We analyzed the effect of low and intermediate antibody titers in clinical and radiological progression. There were no differences between the results of muscle function tests, spirometry or fat fraction analyzed using qMRI between patients with and without antibodies groups at baseline. Moreover, antibody titers did not influence muscle function test, spirometry results or qMRI results at year 1 visit. Most of the LOPD patients developed antibodies against ERT that persisted over time at low or intermediate levels. However, antibodies at these low and intermediate titers might not influence clinical response to the drug.

中文翻译：

---

在ERT治疗的晚期庞贝病患者中，针对低和中等滴度的抗rhGAA抗体的作用研究。

迟发性庞贝病（LOPD）是一种遗传性疾病，其特征是缓慢进行性骨骼肌和呼吸肌无力。有症状的患者接受了用葡糖苷酶α（rhGAA）进行的酶替代疗法（ERT）的治疗。尽管大多数接受ERT治疗的患者都会产生针对rhGAA的抗体，但他们对临床进展的影响尚不完全清楚。我们研究了抗rhGAA抗体对25例ERT治疗患者的临床进展的影响。我们在第0次就诊时对患者进行了评估，在第1年之后的1年后，我们对患者进行了评估。我们在两次就诊时都使用了大腿肌肉的3点Dixon分析进行了几种肌肉功能测试，常规肺活量测定法和定量肌肉MRI（qMRI）。我们还获得了两次就诊时的血清样品，并使用ELISA定量了抗rhGAA抗体。抗体滴度高于1：在我们队列中的18名患者（72％）中确定了200名。7位患者（28％）未产生抗体（0至<1：200），17位患者（68％）已形成低至中效价（1：200至<1：31,200），1位患者（4％）已产生高效价（> 1：31,200）。我们分析了中低抗体效价在临床和放射学进展中的作用。在基线时有和没有抗体组的患者之间，使用qMRI分析的肌肉功能测试，肺活量测定法或脂肪分数的结果之间没有差异。而且，抗体滴度在第1年就诊时不影响肌肉功能测试，肺活量测定结果或qMRI结果。大多数LOPD患者会产生针对ERT的抗体，这些抗体会长期以低或中等水平持续存在。然而，