This is an open-label, randomized, multicenter Phase II clinical study designed to evaluate the cardioprotective effect, to determine the optimal dosages and duration of inhalation, and to assess the clinical safety of the medicinal product Aroxxen® in patients undergoing elective percutaneous coronary intervention (PCI) with stent implantation.

Patients who undergo elective PCI are at risk of myocardial injury associated with the procedure. The study aims to assess whether inhalation of Aroxxen®, administered during the procedure and after it, can reduce markers of myocardial damage and improve clinical outcomes, while maintaining an acceptable safety profile.

Eligible patients will be randomized to receive inhalation of Aroxxen® according to the study protocol or standard therapy without inhalation, depending on the assigned group. The study includes multiple centers and compares different dosing regimens and durations of inhalation in order to identify optimal treatment parameters.

Safety will be evaluated by monitoring adverse events, vital signs, and clinical laboratory parameters throughout the study period. The results of this study are intended to provide data on the safety and potential cardioprotective effects of Aroxxen® and to support further clinical development.

1. Presence of coronary artery disease with stenosis of one or more coronary arteries requiring elective percutaneous coronary intervention for stent implantation (including patients with stable angina pectoris, Canadian Cardiovascular Society functional class II-IV, and patients with post-infarction or atherosclerotic cardiosclerosis with or without angina).
2. Clinically and/or hemodynamically significant coronary artery stenosis confirmed by coronary angiography, with an indication for percutaneous coronary intervention with stent implantation.
3. Age 50 to 80 years inclusive at the time of signing informed consent.
4. Baseline high-sensitivity troponin I within the laboratory reference range, excluding acute coronary syndrome.
5. Written voluntary informed consent obtained after the participant has received full information about the study objectives, methods, risks, and potential benefits.
6. Willingness and ability to comply with all study procedures and visits specified in the protocol.