Panasci L C, Comis R, Ginsberg S, Rudolph A, Theodorakis M, Klag M, Fitzpatrick A, Rubert M, Cable R, Davey F
Cancer Treat Rep. 1980;64(12):1227-33.
Vinblastine-loaded platelets (VLP) have been successfully used in the treatment of idiopathic thrombocytopenic purpura. Three patients with platelet-phagocytizing tumors and thrombocytopenia were treated with VLP. Patient 1 has sustained a response for 11 months. Patient 2 was not evaluable for response because of early death. Patient 3 had a brief partial response. Vinblastine levels were measured by radioimmunoassay in the platelet-rich plasma, platelet-poor plasma, and serum. The pharmacokinetic data obtained on the patients suggest that: (a) the amount of vinblastine bound to platelets in vivo is a function of the platelet-poor plasma vinblastine level and the platelet count; (b) VLP will probably not have any therapeutic advantage, compared with iv vinblastine alone in patients with normal platelet counts; and (c) it appears that delivery of vinblastine was tumor-specific, since the bone marrow serum vinblastine level in patient 2, obtained when the marrow was replaced by tumor cells, was 2.5-fold higher than a simultaneous peripheral blood serum vinblastine level after VLP. Additional studies with VLP appear warranted in patients with platelet-phagocytizing tumors resulting in thrombocytopenia.
载有长春碱的血小板（VLP）已成功用于治疗特发性血小板减少性紫癜。3例患有吞噬血小板肿瘤和血小板减少症的患者接受了VLP治疗。患者1已持续缓解11个月。患者2因早期死亡无法评估缓解情况。患者3有短暂的部分缓解。通过放射免疫分析法测定了富血小板血浆、贫血小板血浆和血清中的长春碱水平。从患者获得的药代动力学数据表明：（a）体内与血小板结合的长春碱量是贫血小板血浆长春碱水平和血小板计数的函数；（b）与单独静脉注射长春碱相比，VLP在血小板计数正常的患者中可能没有任何治疗优势；（c）长春碱的递送似乎具有肿瘤特异性，因为在患者2中，当骨髓被肿瘤细胞取代时获得的骨髓血清长春碱水平比VLP后同时期外周血血清长春碱水平高2.5倍。对于因吞噬血小板肿瘤导致血小板减少的患者，似乎有必要对VLP进行更多研究。
