Acute bacterial sinusitis is one of the most common causes of prescribing systemic antibacterial drugs in otorhinolaryngology. With bacterial etiology of the disease, beta-lactam antibiotics are prescribed, in particular cefixim. Cefixim in the form of dispersible tablets has high clinical and bacteriological efficiency, as well as good tolerability in patients with acute sinusitis. To study the therapeutic equivalence of two drugs of cefixim (reproduced drug Cefixim Express and reference drug Suprax Solutab) in patients with acute bacterial sinusitis. 60 adult patients with a diagnosis of acute bacterial sinusitis took part in a randomized open comparative clinical study. Patients of group 1 (n=30) received the drug Cefixim Express in the form of dispersible tablets 400 mg once a day. Group 2 (n=30) received Suprax Solutab in the form of dispersible tablets 400 mg once a day. The duration of treatment course was 7 days. All patients conducted general clinical and otorhinolaryngological examinations, assessment of symptoms of acute sinusitis, assessment of the general clinical impression of the therapy, tolerance of treatment, analysis of the frequency of unwanted phenomena before treatment, 3 days after the beginning of therapy and after the course completion (7 days). Recovery occurred in 63.3% of patients in group 1 according to the inspection on the 7th day of treatment and in 66.67% of patients in group 2. The rate of clinical symptoms regression by the end of therapy was comparable in the comparison groups. Hyperemia of the nasal mucosa, purulent nasal discharge and difficulty in nasal breathing (p<0.01) regressed by the 7th day in patients of both treatment groups. The incidence of adverse reactions on the 7th day of treatment in group 1 was 10%, in group 2 - 6.7% (p>0.05). The drug Cefixim Express has high therapeutic effectiveness in the treatment of acute bacterial sinusitis, comparable to Suprax Solutab. Cefixime EXPRESS has demonstrated a good tolerability and a favorable safety profile.