The aim of the study was to assess the efficacy and safety of AP203 preparation (RESCOVIN®) in a group of patients with increased incidence to viral and/or bacterial upper respiratory tract infections.

Randomized, double-blind, cross over study conducted under medical supervision on 1) group of 30 patients receiving AP203 mixture in capsule form and 2) group of 30 receiving placebo. After a washout period a group receiving placebo receiver AP203 mixture in syrup form.

The study group was adult patients with an increased incidence of upper respiratory tract infection. During the study, the effect of a mixture of AP203 extracts (RESCOVIN®) on markers of inflammation and oxidative stress and the effect on the incidence of upper respiratory tract infections was assessed.

Inclusion Criteria:

• Women and men, 18-70 years old
• Healthy patients at the time of enrollment to the study (without active upper respiratory tract infection)
• Presence of 2 or more episodes of upper respiratory tract infections or >=2 episodes of cold during the year
• Patients with chronic upper respiratory tract diseases including bronchial asthma
• Signed informed consent
• Women: contraception or postmenopausal age

Exclusion Criteria:

• Intake of supplements containing plant extracts, polyphenols or anthocyanins for the 3 months prior to the study initiation
• Acute inflammation
• Oral immunosuppressive drugs
• Steroid, anti-allergic drugs in exacerbations of chronic disease at least 2 months from the start of study participation
• Antibiotic therapy 1 month prior to study initiation
• Participation in another clinical trial;
• Oncological disease, autoimmune disease, severe liver dysfunction, tuberculosis, leukaemia, multiple sclerosis, AIDS, rheumatoid arthritis, organ transplantation;
• Hypersensitivity/allergy to any of the ingredients of the product, allergy to plants of the Asteraceae family (e.g. chamomile, calendula);
• Women who are pregnant or planning to become pregnant during the study period;