Atara Biotherapeutics (ATRA) shares rallied 10% in the last trading session to close at $14.26. This move can be attributable to notable volume with a higher number of shares being traded than in a typical session. This compares to the stock's 2.6% gain over the past four weeks.The price rise can be attributed to growing investor optimism regarding Atara’s recent development related to its lead product candidate, tabelecleucel (tab-cel), a novel T-cell immunotherapy, which has been developed for the treatme ...