In Japan, the Nikkei 225 gained 0.65% while the Topix index rose 0.78%.
Australian stocks surged, with the S & P / ASX 200 rising 1.34%.
The MSCI’s largest Asia-Pacific stock index outside of Japan traded up 0.4%.
The companies plan to seek emergency clearance for Covid antiviral treatment after the drug has shown “convincing results” in clinical trials.
Markets in China are closed for most of this week for the holidays and are expected to reopen on Friday. South Korean markets are also closed on Mondays for a public holiday.
Currencies and oil
The US dollar index, which tracks the greenback against a basket of its peers, was at 93.948 after falling recently from above 94.4.
Oil prices were down on the morning of Asian trading hours, with international benchmark Brent crude futures down 0.19% to $ 79.13 a barrel. US crude futures fell 0.26% to $ 75.68 a barrel.
– CNBC’s Chloe Taylor contributed to this report.