** Shares of biotech firm Aligos Therapeutics ALGS.O jump 23.1% to $7.2O after the bell

** ALGS says has received upfront payment of $25 mln from exclusive license deal of pevifoscorvir sodium in Greater China with Xiamen Amoytop Biotech 688278.SS

** Under terms, ALGS is also eligible to receive up to $420 mln in clinical, regulatory and sales milestones

** Pevifoscorvir sodium is ALGS' experimental hepatitis B drug, designed to block the virus and reduce disease markers

** Pevifoscorvir sodium was granted Breakthrough Therapy Designation from the Center for Drug Evaluation (CDE) of China's National Medical Products Administration

** ALGS has fallen 36.1% YTD