Filippone Edward J, Gulati Rakesh, Farber John L
Division of Nephrology, Department of Medicine, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA, United States.
Department of Pathology, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA, United States.
Front Nephrol. 2025 Feb 4;5:1545329. doi: 10.3389/fneph.2025.1545329. eCollection 2025.
Primary IgA nephropathy (IgAN) is the most common form of primary glomerulopathy. A slowly progressive disease presenting in the young to middle-aged, most patients with reduced eGFR or proteinuria will progress to end-stage kidney disease (ESKD) in their lifetimes. The pathogenesis involves increased production of galactose-deficient IgA1 (Gd-IgA1) that forms immune complexes that deposit in the glomerulus, eliciting mesangial cell proliferation, inflammation, and complement activation. The backbone of therapy is supportive, including lifestyle modifications, strict blood pressure control, and renin-angiotensin system inhibition targeting proteinuria < 300 mg/day. Sodium-glucose transporter 2 inhibitors are indicated for persisting proteinuria or declining eGFR. Sparsentan is indicated for persisting proteinuria. Immunosuppression should be considered for all patients at risk for progression (persisting proteinuria and/or declining eGFR). To reduce Gd-IgA1 production, targeted-release budesonide is approved. Agents targeting B cell survival factors APRIL or BAFF/APRIL have significantly reduced Gd-IgA1 production and proteinuria in phase 2 trials but await phase 3 data for approval. To reduce inflammation, high-dose steroids are ineffective and toxic in Caucasian patients, although lower-dose regimens may be effective in Chinese patients. Complement inhibition is being actively studied. The factor B inhibitor iptacopan has conditional approval. The terminal pathway inhibitors cemdisiran and ravulizumab show promise in phase 2 studies. Our current approach for those requiring immunosuppression involves combining the reduction of Gd-IgA1 (nefecon) with suppressing the effects of inflammation (iptacopan). The optimal duration of such therapy is uncertain. Clearly, there is more to be learned with many trials underway.
原发性IgA肾病(IgAN)是原发性肾小球病最常见的形式。这是一种在年轻人至中年人中呈现缓慢进展的疾病,大多数估算肾小球滤过率(eGFR)降低或有蛋白尿的患者在其一生中会进展为终末期肾病(ESKD)。其发病机制涉及半乳糖缺陷型IgA1(Gd-IgA1)产生增加,Gd-IgA1形成免疫复合物沉积于肾小球,引发系膜细胞增殖、炎症和补体激活。治疗的主要方法是支持性治疗,包括生活方式调整、严格控制血压以及抑制肾素-血管紧张素系统,目标是使蛋白尿<300mg/天。钠-葡萄糖协同转运蛋白2抑制剂适用于持续性蛋白尿或eGFR下降的情况。司帕生坦适用于持续性蛋白尿。对于所有有疾病进展风险(持续性蛋白尿和/或eGFR下降)的患者,应考虑免疫抑制治疗。为减少Gd-IgA1的产生,靶向释放型布地奈德已获批准。在2期试验中,靶向B细胞存活因子增殖诱导配体(APRIL)或B细胞活化因子(BAFF)/APRIL的药物已显著降低Gd-IgA1的产生和蛋白尿,但尚需等待3期试验数据以获得批准。为减轻炎症,高剂量类固醇对白人患者无效且有毒性,不过低剂量方案对中国患者可能有效。补体抑制正在积极研究中。因子B抑制剂依他库帕有条件获批。终末途径抑制剂西姆迪西兰和ravulizumab在2期研究中显示出前景。我们目前对需要免疫抑制治疗的患者的治疗方法是将减少Gd-IgA1(奈非考泮)与抑制炎症作用(依他库帕)相结合。这种治疗的最佳持续时间尚不确定。显然,随着众多试验的进行,还有更多有待了解的内容。