This clinical trial is designed as an open-label, dose-escalating, single-centre trial of weight-adjusted dose regimens of microplasmin administered intra-arterially as an infusion to patients with acute peripheral arterial occlusion. Patients who meet all inclusion criteria and none of the exclusion criteria will be administered study drug for up to 4 hours. Different dose regimens will be evaluated in an ascending-dose fashion; an infusion will be administered for up to 4 hours.