Bio-tech firm JCR Pharmaceuticals rallied 5.9 percent to 2,904 yen after a report said it will produce undiluted Covid-19 vaccine developed by the British drug group AstraZeneca and Oxford University.
The move has put a brake on a massive spending spree in Hong Kong by mainland traders looking to take advantage of relatively cheap shares in the city.
Investors are also keeping tabs on the ongoing earnings season, while the Federal Reserve's next board meeting this week is expected to shed light on its plans for monetary policy in light of the stimulus proposal.