A new influenza drug in development at AstraZeneca (AZ) – which could be life-saving in severe cases – has been given an expedited review by the FDA.
The fast-track status has been awarded to MEDI8852 on the strength of preliminary data showing that the antibody-based drug can be given safely and recognises the acute need for additional drug treatment options for flu.
While neuraminidase inhibitor therapies such as Roche’s oral Tamiflu (oseltamivir) and GlaxoSmithKline’s inhaled Relenza (zanamivir) have been available for years, but are recognised to have limited effectiveness, generally just making symptoms a little milder.
However, organisations such as the US Centers for Disease Control and Prevention (CDC) recommend the use of these drugs in patients who are hospitalised for flu, pointing to observational data suggesting they may reduce serious flu complications.
MEDI8852 is described as a ‘pan-influenza’ monoclonal antibody that binds to haemagglutinin – which along with neuraminidase is another key constituent of the flu virus – and could potentially be used with neuraminidase inhibitors to improve efficacy.
The neuraminidase and haemagglutinin proteins are highly variable between flu strains, which is why the profile of the strain circulating in any flu season needs to be predicted to allow an appropriate vaccine type to be developed.
AZ’s antibody targets the haemagglutinin stem – shared by all 18 known influenza A virus subtypes – so if successful in clinical trials could become a universal treatment for flu.
MEDI8852 is currently being tested in a phase Ib/IIa clinical trial both as a monotherapy and in combination with Tamiflu in acute uncomplicated influenza caused by influenza type A strains. The drug is being delivered as a single intravenous dose in the study.
In the US an estimated 36,000 people die and more than 200,000 are hospitalised each year because of flu. The severity of the virus can be exacerbated if the prevailing strain differs from the predicted strain, as occurred during the 2014/2015 flu season.