STUDIES IN PORPHYRIA III, HEME, AND TIN MESOPORPHYRIN IN ACUTE PORPHYRIAS

急性卟啉症是一种遗传性代谢紊乱，会导致危及生命的神经系统症状，可以通过静脉注射血红素进行治疗。 目的是研究锡中卟啉（血红素降解抑制剂），以提高血红素治疗这些疾病的效果。具体目的是确定1）锡中卟啉和血红素的最佳剂量组合，用于降低急性间歇性卟啉症稳定患者中的卟啉前体水平; 2）当在卟啉症的实际发作中与血红素一起给予时，锡中卟啉的安全性和有效性; 3）锡中卟啉用于降低预防卟啉症发作所需的血红素输注频率的安全性和有效性。 如果血红素精氨酸盐的供应有限，可以用血红素白蛋白代替。 锡中卟啉很可能被批准用于治疗新生儿黄疸，并将成为可用于卟啉症以及。 因此，重要的是要知道，正如初步报告所建议的那样，它对卟啉病是安全有效的，以及最佳剂量。 这些研究将确定锡中卟啉是否安全有效，从而为美国急性卟啉病患者提供一种重要的治疗选择。

Acute porphyrias are inherited metabolic disorders that cause life-threatening neurological symptoms, and are treated with intravenous heme. The objective is to study tin mesoporphyrin (an inhibitor of heme degradation) for enhancing the effects of heme therapy in these disorders. The specific aims are to determine 1)the optimal dose combinations of tin mesoporphyrin and heme for reducing porphyrin precursor levels in stable patients with acute intermittent porphyria; 2)safety and efficacy of tin mesoporphyrin when given with heme in acture attacks of porphyria 3)safety and efficacy of tin mesoporphyrin for decreasing the frequency heme infusions needed to prevent attacks of porphyria. Heme albumin may be substituted if the supply of heme areginate is limited. Tin mesoporphyrin is likely to be approved for treatment of neonatal jaundice, and will become available for use in porphyria as well. Therefore it is important to know if, as suggested by preliminary reports, it is safe an effective in porphyria and the optimal dosage. The studies will determine whether tin mesoporphyrin is safe and effective and thereby addresses an important management option for patients with acute porphyrias in the U.S.