Pharmacotherapeutic group: Influenza vaccine, ATC Code: J07BB02.
Mechanism of action
Influenza vaccine TIV Viatris provides active immunisation against three influenza virus strains: an A/(H1N1) strain, an A/(H3N2) strain, and a B strain. It induces humoral antibodies against the haemagglutinins. These antibodies neutralise influenza viruses.
Specific levels of haemagglutination-inhibition (HI) antibody titre post-vaccination with inactivated influenza virus vaccines have not been correlated with protection from influenza illness but the HI antibody titres have been used as a measure of vaccine activity.
An immune response is generally obtained within 2 to 3 weeks. The duration of postvaccinal immunity to homologous strains or to strains closely related to the vaccine strains varies but is usually 6-12 months.
Pharmacodynamic effects
Data for Influvac sub-unit Tetra are relevant to Influenza vaccine TIV Viatris because both vaccines are manufactured using the same process.
Efficacy and immunogenicity of Influenza vaccine TIV Viatris in children 6 - 35 months of age
The efficacy of Influvac sub-unit Tetra was evaluated in a randomised, observer blind, non-influenza vaccine-controlled study (INFQ3003) conducted during 3 influenza seasons 2017 to 2019 in Europe and Asia. Healthy subjects aged 6 - 35 months received two doses of Influvac sub-unit Tetra (N=1005) or non-influenza control vaccine (N=995) approximately 28 days apart. Vaccine efficacy was assessed for the prevention of reverse transcription polymerase chain reaction (RT-PCR) -confirmed influenza A and/or B disease due to any influenza strain. All RT-PCR-positive specimens were further tested for viability in cell culture and to determine whether the circulating viral strains matched those in the vaccine.
Table: Efficacy in children 6 – 35 months of age
| | Influvac sub-unit Tetra N=1005 | Non-influenza control-vaccine N=995 | Vaccine efficacy (95% CI) |
| Laboratory-confirmed influenza caused by: | n | n | |
| - Any influenza A or B strain | 59 | 117 | 0.54 (0.37 - 0.66) |
| - Culture confirmed vaccine matching strains | 19 | 56 | 0.68 (0.45 - 0.81) |
Vaccine efficacy: proportion of influenza cases prevented by the vaccination
N=number of subjects vaccinated
n=number of influenza cases
CI=confidence interval
Table: Seroconversion rates in children 6 – 35 months of age
| | Influenza season NH 2017-20181 N=348 | Influenza season NH 2018-20191 N=359 | Influenza season SH 20191 N=225 |
| | Seroconversion Rates (95% confidence interval) |
| A/H1N1 | 74.4% (69.5%, 78.9%) | 76.0% (71.3%, 80.4%) | 69.8% (63.3%, 75.7%) |
| A/H3N2 | 92.5% (89.2%, 95.0%) | 86.6% (82.7%, 90.0%) | 86.2% (81.0%, 90.4%) |
| B (Yamagata) | 35.5% (30.4%, 40.8%) | 56.0% (50.7%, 61.2%) | 16.9% (12.2%, 22.4%) |
| B (Victoria) | 26.5% (21.9%, 31.5%) | 65.2% (60.0%, 70.1%) | 47.6% (40.9%, 54.3%) |
N= number of subjects included in immunogenicity analysis
1containing recommended strains by WHO for respective season for quadrivalent vaccines
Immunogenicity of Influenza vaccine TIV Viatris in children 3 – 17 years of age and adults (including elderly)
Clinical studies performed in adults (INFQ3001) and children of 3 to 17 years of age (INFQ3002) assessed the immunogenicity of Influvac sub-unit Tetra and its non-inferiority to trivalent Influenza vaccine TIV Viatris formulations for the postvaccination HI Geometric mean antibody titres (GMT) and seroconversion rates. Children received one or two doses of vaccine based on their influenza vaccine history.
Table: Post-vaccination GMTs and seroconversion rates in adults
| Adults 18 – 60 years of age | Influvac sub-unit Tetra N=768 | Influenza vaccine TIV Viatris 1 N=112 | Influenza vaccine TIV Viatris 2 N=110 |
| GMT (95% confidence interval) |
| A/H1N1 | 272.2 (248.0, 298.8) | 304.4 (235.1, 394.1) | 316.0 (245.1, 407.3) |
| A/H3N2 | 442.4 (407.6, 480.2) | 536.5 (421.7, 682.6) | 417.0 (323.7, 537.1) |
| B (Yamagata)3 | 162.5 (147.8, 178.7) | 128.7 (100.3, 165.2) | 81.7 (60.7, 109.9) |
| B (Victoria)4 | 214.0 (195.5, 234.3) | 85.1 (62.6, 115.6) | 184.7 (139.0, 245.3) |
| Seroconversion rate (95% confidence interval) |
| A/H1N1 | 59.4% (55.8%, 62.9%) | 65.5% (55.8%, 74.3%) | 64.8% (55.0%, 73.8%) |
| A/H3N2 | 51.3% (47.7%, 54.9%) | 61.6% (51.9%, 70.6%) | 55.5% (45.7%, 64.9%) |
| B (Yamagata)3 | 59.2% (55.7%, 62.8%) | 58.7% (48.9%, 68.1%) | 40.9% (31.6%, 50.7%) |
| B (Victoria)4 | 70.2% (66.8%, 73.4%) | 51.4% (41.6%, 61.1%) | 66.4% (56.7%, 75.1%) |
| Elderly 61 years of age and older | Influvac sub-unit Tetra N=765 | Influenza vaccine TIV Viatris 1 N=108 | Influenza vaccine TIV Viatris 2 N=110 |
| GMT (95% confidence interval) |
| A/H1N1 | 127.2 (114.9, 140.9) | 142.4 (107.6, 188.3) | 174.2 (135.9, 223.3) |
| A/H3N2 | 348.5 (316.8, 383.5) | 361.5 (278.3, 469.6) | 353.4 (280.7, 445.0) |
| B (Yamagata)3 | 63.7 (57.7, 70.4) | 57.4 (43.6, 75.7) | 27.3 (20.7, 36.0) |
| B (Victoria)4 | 109.4 (98.1, 122.0) | 48.0 (34.6, 66.6) | 106.6 (79.7, 142.8) |
| Seroconversion rate (95% confidence interval) |
| A/H1N1 | 50.3% (46.7%, 54.0%) | 56.6% (46.6%, 66.2%) | 58.2% (48.4%, 67.5%) |
| A/H3N2 | 39.3% (35.8%, 42.9%) | 44.4% (34.9%, 54.3%) | 43.6% (34.2%, 53.4%) |
| B (Yamagata)3 | 49.9% (46.2%, 53.5%) | 46.2% (36.5%, 56.2%) | 30.0% (21.6%, 39.5%) |
| B (Victoria)4 | 53.6% (50.0%, 57.2%) | 25.0% (17.2%, 34.3%) | 55.6% (45.7%, 65.1%) |
N= number of subjects included in immunogenicity analysis
1containing A/H1N1, A/H3N2 and B (Yamagata lineage)
2containing A/H1N1, A/H3N2 and B (Victoria lineage)
3recommended B strain by WHO for the season 2014-2015 NH for trivalent vaccines
4additional recommended B strain by WHO for season 2014-2015 NH for quadrivalent vaccines
Table: Seroconversion rates in children 3 – 17 years of age
| Children 3 - 17 years of age | Influvac sub-unit Tetra N=396 | Influenza vaccine TIV Viatris 1 N=389 | Influenza vaccine TIV Viatris 2 N=399 |
| Seroconversion rate (95% confidence interval) |
| A/H1N1 | 60.1% (55.1% , 65.0%) | 61.8% (56.7%, 66.6%) | 59.1% (54.1%, 64.0%) |
| A/H3N2 | 80.6% (76.3% , 84.3%) | 82.4% (78.3%, 86.1%) | 80.7% (76.5%, 84.5%) |
| B (Yamagata)3 | 79.3% (75.0% , 83.2%) | 73.1% (68.4%, 77.5%) | 28.1% (23.7%, 32.8%) |
| B (Victoria)4 | 76.5% (72.0% , 80.6%) | 39.5% (34.6%, 44.6%) | 72.7% (68.0%, 77.0%) |
N= number of subjects included in immunogenicity analysis
1containing A/H1N1, A/H3N2 and B (Yamagata lineage)
2containing A/H1N1, A/H3N2 and B (Victoria lineage)
3recommended B strain by WHO for the season 2016-2017 NH for trivalent vaccines
4additional recommended B strain by WHO for season 2016-2017 NH for quadrivalent vaccines