By Rebecca Spalding

(Reuters) – British drugmaker GlaxoSmithKline Plc and Vir Biotechnology Inc will expand their existing partnership developing antibody therapies for COVID-19 to research therapies for other diseases, the companies said on Wednesday.

The companies will research monoclonal antibody treatments for influenza and other respiratory illnesses as a part of the agreement, they said.

As a part of the deal, GSK will make a further $120 million equity investment in Vir and will pay the company an additional upfront payment of $225 million.

The companies announced a partnership last year to research COVID-19 treatments. Unlike vaccines, antibody treatments are designed to be given to patients that have been diagnosed with the illness with the aim of decreasing the severity of the disease.

One of the companies’ experimental therapies for COVID-19 is currently being studied in two global final stage trials. Results from one of those studies are expected in the first quarter of 2021.

San Francisco-based biotechnology company Vir, which is run by former Biogen Chief Executive Officer George Scangos, was founded in 2016 to research infectious diseases at a time when that area of focus was rare for cutting-edge biotechnology start-ups.

The COVID-19 pandemic has since spurred large pharma companies’ interest in researching new ways to combat infectious pathogens, including influenza.

The effectiveness of standard flu vaccines varies year to year based on how well researchers are able to predict that season’s dominant strains months in advance. The effectiveness of the vaccine can also vary depending on the age of the recipient and other factors, according to the Centers for Disease Control and Prevention.

The companies said they would work to further develop Vir’s experimental treatment for influenza A. The companies said that people 65 and older with underlying conditions have a higher risk of dying of the virus and that historically, vaccines have had lower efficacy in this group.

(Reporting by Rebecca Spalding; Editing by Rashmi Aich)