Australia’s Biota Holdings will be hoping for a cash boost following the news that its commercial partner GlaxoSmithKline is to send an additional two million packs of the antiviral treatment Relenza to Japan by April.

GSK says that it will start shipping the packs now in addition to the three million originally set aside for the influenza season in Japan. Demand for Relenza (zanamivir) has “increased dramatically,” the firm noted, due to reports that “most of the prevailing A/H1N1 influenza virus, which accounts for about half of the current epidemic, are resistant to another anti-influenza virus drug this year”. GSK is referring to Roche’s Tamiflu (oseltamivir).

GSK concluded by saying it believes that currently, “there is enough Relenza in distribution in the market”, but the additional importation will enable the firm “to maintain a stable supply”.

All this should be good news for Biota, which receives a 7% royalty from GSK on Relenza sales. The Japanese deal, combined with the announcement last month that the UK government has ordered an additional 10.6 million courses of the drug, means that the Melbourne-based could be set for a windfall of around $14 million, according to analysts at ABN Amro Morgans.

Biota has licensing deals with AstraZeneca (respiratory syncytial virus) and Boehringer Ingelheim (hepatitis C), and says it also has “a key partnership with Daiichi-Sankyo for the development of second generation influenza antivirals”. The company also notes that it has clinical trials underway with its lead compound for human rhinovirus infection in patients with compromised respiration or immune systems.

Biota, which has seen its stock soar this year, settled a long-running legal row with GSK last July which saw the UK drug major accused of not doing enough to promote Relenza.