Trial Outcomes & Findings for Safety, Reactogenicity, Immunogenicity, Efficacy of Influenza Vaccines Grippol® Quadri and Grippol® Plus in Volunteers (NCT NCT03849560)

Race and Ethnicity were not collected from any participant.

Percent of subjects achieving seroconversion (the number of volunteers with antibody titer \[of at least 1:40\] increased more than 4-fold versus baseline \[assessed by HAIR\]) for antigens: influenza virus type А - H1N1, influenza virus type А - H3N2, influenza virus type В - Yamagata and Victoria lineage, based on assessment at Visit 7.

To antigens: influenza virus type А - H1N1, influenza virus type А - H3N2, influenza virus type В - Yamagata and Victoria lineage. Based on assessment at Visit 7.

Antibody titer is determined using the hemagglutination inhibition reaction (HAIR), the method recommended by the World Health Organization (WHO) for influenza vaccine efficacy evaluation. As an additional method for 150 volunteers (50 volunteers in each group), a microneutralization assay is planned (the data will be used to evaluate seroprotection). Seroprotection: share of subjects achieving protective antibody titer (1:40 and more, assessed by HAIR and microneutralization test) to antigens H1N1, H3N2, Yamagata and Victoria lineages.

Incidence of influenza and acute respiratory infection (ARI) based on assessment at Visit 11.

A case of influenza and ARI is considered as a case of flu-like symptoms (according to: European center for Disease Prevention and Control (ECDC) TECHNICAL DOCUMENT Protocol for case-control studies to measure pandemic and seasonal influenza vaccine effectiveness in the European Union and European Economic Area Member States/ ECDC, 2009): if a subject seeks physician's advice regarding unexpected occurrence of at least one of 4 systemic symptoms: 1) chills or fever, 2) distress, 3) headache, 4) myalgia and at least one of 3 respiratory symptoms: 1) cough, 2) sore throat, 3) respiratory distress. Study doctor will perform evaluation of influenza or ARI duration and severity, making phone calls to subject. A case with at least 1 of the complications listed below will be considered severe: the necessity of hospitalization; influenza-associated pneumonia; influenza-associated cardiovascular disorder; death.

Fold Change in Geometric Mean Titer of Serum Antibodies (antigens H1N1,H3N2, Yamagata and Victoria lineages) based on assessment data at visit 7.

A case of influenza and ARI is considered as a case of flu-like symptoms (according to: ECDC TECHNICAL DOCUMENT Protocol for case-control studies to measure pandemic and seasonal influenza vaccine effectiveness in the European Union and European Economic Area Member States/ European center for Disease Prevention and Control, 2009): if a subject seeks physician's advice regarding unexpected occurrence of at least one of 4 systemic symptoms: 1) chills or fever, 2) distress, 3) headache, 4) myalgia and at least one of 3 respiratory symptoms: 1) cough, 2) sore throat, 3) respiratory distress. Study doctor will perform evaluation of influenza or ARI duration and severity, making phone calls to subject. A case with at least 1 of the complications listed below will be considered severe: the necessity of hospitalization; influenza-associated pneumonia; influenza-associated cardiovascular disorder; death.

Average time (months) to the first reported episode of influenza and ARI based on assessment at Visit 11.

As an additional method for 149 volunteers, a microneutralization assay is planned (the data will be used to evaluate seroprotection). Seroprotection: share of subjects achieving protective antibody titer (1:40 and more, assessed by HAIR and microneutralization test) to antigens H1N1, H3N2, Yamagata and Victoria lineages.

The presence of ARI symptoms in participants in each group is assessed throughout the study. The presence of a symptom at least once is taken into account in the analysis if the participant has several filling out of the questionnaire.