A single-center, open-label, randomized, placebo-controlled, prospective phase II clinical trial to investigate the efficacy of low-dose albumin in patients with ischemic stroke with an indication for vasographic intervention. The clinical trial consists of the following phases: Screening, randomization, treatment phase - administration of albumin/placebo and vasographic intervention (with the duration of all these 3 phases in the order of hours) and a follow-up phase, which takes place first in the intensive care unit (ICU) and then in a standard ward and lasts 90 (±7) days. The clinical trial ends with the End of Study/Day 90 visit. The total maximum duration of patient participation in the clinical trial is therefore 97 days, including Follow-up.

Ischemic stroke is caused by local perfusion impairment due to thromboembolism or thrombosis at the site of perfusion impairment. The damaged brain area is projected into the patient's neurological clinical picture. The primary stroke cannot be influenced by therapeutic procedures, however, the area of the so-called penumbra (the surroundings of the ischemic lesion, where vasoreactivity is impaired and the blood-brain barrier is more or less damaged) can be, which is the main goal of therapy, as well as improving the neurological clinical outcome of patients as much as possible (thrombolysis, neuroangiointervention). Research over the past 20 years has highlighted the importance of the endothelial glycocalyx (EG) and has proposed a number of concepts and substances with a protective and reparative effect.

Albumin has come to the forefront of interest. The study assumes a benefit for patients in the form of non-circulatory effects of administered albumin: improvement of EG condition in the penumbra area of the ischemic focus, improvement of microrheology, and antioxidant protection. Albumin therapy has been used for 80 years and is generally well tolerated. Allergy to albumin is rare, as it is a protein of the body's own from healthy donors. The concomitantly used medicinal products are highly purified. The selected dosage should not endanger the patient in any way in terms of circulatory overload, pulmonary edema, and, we assume, also in terms of bleeding into the ischemic focus of the brain.

Study drug: albumin. Any albumin available on the market in the dose and strength specified in the protocol can be used. The reference SmPC is Alburex (manufacturer CSL Behring). Placebo: Fresenius Kabi 0.9% saline solution.

It is planned to enroll 100 patients.

Inclusion Criteria:

• ischemic stroke in the anterior circulation with or without thrombolysis administration
• vasographic intervention indication

Exclusion Criteria:

• pregnancy, breastfeeding
• known albumin hypersensitivity
• hypervolemia, hyperhydration
• hypernatremia
• another study participation