Phase II data from BiondVax heat up race for first universal flu vaccine
This article was originally published in Scrip
Data presented at the World Vaccines Congress by BiondVax suggest that the quest to develop a universal flu vaccine may soon be concluded.
Influenza causes an estimated 500,000 deaths each year, with the elderly accounting for more than 90% of influenza-related fatalities. The continued emergence of new variants of influenza viruses causing epidemics and periodic worldwide pandemics has prompted attempts to develop a universal influenza vaccine. To date, such efforts had been unfruitful with no agent progressing beyond Phase II clinical trials.
BiondVax's recombinant universal influenza vaccine, Multimeric-001 (M-001), is currently in Phase II studies. M-001 comprises a single polypeptide containing nine highly conserved T- and B-cell epitopes taken from three influenza virus proteins, conferring protection against a broad range of influenza strains.
At this year's World Vaccines Congress, the chief scientific officer at BiondVax, Dr Tamar Ben-Yedidia, presented data from the vaccine's second Phase II clinical trial, performed in 120 elderly patients aged 65 years or older, showing that M-001 stimulates immune responses when administered as a primer prior to seasonal influenza immunization.
M-001 was originally designed as a standalone universal influenza vaccine, but these new data on its effectiveness as a boosting agent have given it a second potential indication as a booster to currently available flu vaccines.
Dr Ben-Yedidia revealed that M-001 was able to elicit an increase in both humoral (antibodies) and cellular immunity, when administered prior to the seasonal influenza vaccine. Administration of M-001 enhanced efficacy of existing vaccines by increasing seroconversion towards haemagglutination by up to 70%, and by causing expanded production of T-cells for all test strains of the virus. M-001 also showed a good safety profile.
On the downside, the immune response to M-001 was higher in those subjects given two priming doses of M-001 prior to immunisation rather than one. Datamonitor believes that requiring two priming doses may hinder the success of the vaccine, as compliance could become problematic if patients are required to visit their physicians three times for a full set of vaccine doses.
Dr Ben-Yedidia is confident that this will not hinder M-001's potential arguing that its ability to alleviate a significant economic burden on the healthcare system, will persuade health authorities to encourage its use. Furthermore, elderly patients generally visit their physicians more often than the rest of the community, and thus are more amenable to a multiple immunization schedule.
Datamonitor believes that more data surrounding this issue will be required before the scientific and health communities are convinced, as it is well documented that multiple dose vaccination schedules hinder compliance rates. Nevertheless, these results suggest that M-001 may function as an influenza vaccine booster even if its efficacy as a universal influenza vaccine does not pan out.
BiondVax is planning two more Phase II studies before initiating a large Phase III clinical trial. Other companies are also developing universal influenza vaccines, with SEEK, a company that also has a universal influenza vaccine candidate in Phase II development, posing as BiondVax's strongest competitor.
While a universal influenza vaccine may be years away, the agent that enjoys first-to-market advantage is likely to be the most successful.
Haylyn Wong is an analyst at Datamonitor Healthcare and a contributing editor to Scrip Intelligence