In short
GSKVX000000077509 is an investigational influenza vaccine being studied in Phase 3 clinical trials. The trials include adults aged 18 to 64 and adults 65 years and older, with a combined enrolment of 57,000 participants. The research compares this vaccine against approved influenza vaccines to see whether it produces a similar immune response and offers similar protection against laboratory-confirmed influenza.
Key points
- Phase 3 trials are testing GSKVX000000077509 against approved influenza vaccines.
- The largest trial enrolled 54,000 adults aged 65 years and older.
- A second trial enrolled 3,000 adults aged 18 to 64 years.
- Both trials measure immune response and safety after a 0.5 ml intramuscular injection.
- The comparator vaccines include Efluelda and Alpharix, both inactivated influenza vaccines.
- Both trials were authorised in the EU Clinical Trials Information System.
What is GSKVX000000077509?
GSKVX000000077509 is an investigational influenza vaccine. It is one of several vaccine components being tested together in a single 0.5 ml intramuscular injection; the other components are GSKVX000000077430, GSKVX000000077508, GSKVX000000077506, GSKVX000000077510 and GSKVX000000077507. The vaccine is not yet authorised as a medicine; it is being compared with already approved influenza vaccines in Phase 3 trials.
How does GSKVX000000077509 work?
The registry records describe GSKVX000000077509 as part of a trivalent influenza vaccine, meaning it is designed to target three influenza strains. The comparator vaccine Efluelda is described as a trivalent influenza vaccine made from split, inactivated virus with 60 micrograms of haemagglutinin (HA) per strain. The trials measure haemagglutination inhibition (HI) titres and neuraminidase inhibition (NI) titres, which reflect how well the immune system produces antibodies against the influenza virus surface proteins.
Which conditions is GSKVX000000077509 studied for?
- Influenza in adults aged 65 years and older — one trial focuses on this age group because older adults are at higher risk of complications from influenza.
- Influenza in adults aged 18 to 64 years — a second trial studies the vaccine in younger adults and compares their immune response with that of older adults.
How is GSKVX000000077509 given?
GSKVX000000077509 is given as a 0.5 ml injection into the muscle (intramuscular use). The same dose and route are used for the comparator vaccines Efluelda and Alpharix.
What do the clinical trials show?
Two Phase 3 trials are registered for GSKVX000000077509, both authorised in the EU Clinical Trials Information System. The larger trial, with 54,000 participants aged 65 years and older, aims to show that the investigational vaccine is not inferior to Efluelda in preventing laboratory-confirmed influenza-like illness caused by influenza A subtypes H1N1 or H3N2 or influenza B/Victoria. The smaller trial, with 3,000 participants aged 18 to 64 years, aims to show that the immune response in younger adults is not inferior to the immune response in adults aged 65 and older from the larger trial, and that the investigational vaccine is not inferior to the trivalent influenza vaccine Flu D-TIV in terms of immune response to HA antigens.
What are the trials measuring?
The older-adult trial measures the first occurrence of laboratory-confirmed influenza-like illness at least 14 days after vaccination, as well as solicited side effects during the first 7 days, unsolicited adverse events during the first 28 days, and serious adverse events and adverse events of special interest up to the end of the influenza season with at least 180 days of follow-up. The younger-adult trial measures HI titres and NI titres at day 29, HI seroconversion from baseline to day 29, solicited side effects during the first 7 days, unsolicited adverse events during the first 28 days, and serious adverse events and adverse events of special interest up to 6 months after vaccination.
Who can take part in these trials?
One trial is open to adults aged 65 years and older. The other trial is open to adults aged 18 to 64 years. Both trials involve a single intramuscular injection of 0.5 ml.
What side effects are known?
The registry records do not provide a list of side effects for GSKVX000000077509. The trials collect information on solicited administration site and systemic events during the first 7 days, unsolicited adverse events during the first 28 days, and serious adverse events and adverse events of special interest over longer follow-up periods.