Witzig Thomas E
Division of Hematology, Department of Internal Medicine, Mayo Clinic and Mayo Foundation, Stabile 6, 200 SW First Street, Rochester, MN 55905, USA.
Best Pract Res Clin Haematol. 2006;19(4):655-68. doi: 10.1016/j.beha.2006.05.002.
Radioimmunotherapy (RIT) combines the targeting advantage of a monoclonal antibody with the radiosensitivity of non-Hodgkin lymphoma (NHL) cells. There are now two radioimmunoconjugates (RICs) - ibritumomab tiuxetan (Zevalin) and tositumomab (Bexxar) - that are approved by the FDA in the US for relapsed low-grade or follicular B-cell NHL. Both agents target the CD20 antigen on B-cell lymphoma cells. In relapsed disease, single doses of RIT produce an 80% overall response rate, with approximately 20% of patients achieving durable responses. RIT is very well tolerated and is delivered on an outpatient basis over 1 week. The only significant toxicity is reversible myelosuppression. Both RIT agents have demonstrated high anti-tumor activity in patients who are refractory to rituximab. Current trials are testing RIT as initial therapy with rituximab maintenance, as adjuvant therapy after chemotherapy, or in high-dose protocols with stem-cell support.
放射免疫疗法（RIT）将单克隆抗体的靶向优势与非霍奇金淋巴瘤（NHL）细胞的放射敏感性相结合。目前有两种放射免疫偶联物（RICs）——替伊莫单抗（泽瓦林）和托西莫单抗（贝沙罗汀）——已在美国获得美国食品药品监督管理局（FDA）批准，用于复发性低度或滤泡性B细胞NHL。这两种药物均靶向B细胞淋巴瘤细胞上的CD20抗原。在复发性疾病中，单剂量的RIT产生的总体缓解率为80%，约20%的患者实现持久缓解。RIT耐受性良好，在门诊进行，为期1周。唯一显著的毒性是可逆性骨髓抑制。两种RIT药物在对利妥昔单抗难治的患者中均显示出高抗肿瘤活性。目前的试验正在测试RIT作为利妥昔单抗维持的初始治疗、化疗后的辅助治疗或有干细胞支持的高剂量方案。
