What happened Shares of Aptose Biosciences (NASDAQ: APTO) were skyrocketing 70.6% higher as of 11:39 a.m. EDT on Wednesday. The huge gain came after the company provided a fourth-quarter update following the market close on Tuesday that featured new results from an early-stage clinical study evaluating luxeptinib in treating acute myeloid leukemia (AML). So what Aptose announced "encouraging anti-leukemic activity" has been observed so far in its phase 1 study of luxeptinib in treating AML. That's perhaps an understatement. One patient in the study has experienced a complete remission with no safety issues. The company also stated that luxeptinib was "broadly potent against AML cells, suggesting potential across [the] entire AML patient population." Image source: Getty Images. This news prompted some analysts to become more bullish about the biotech stock. For example, Oppenheimer's Matthew Biegler raised his price target for Aptose to $9, a 145% premium to the stock's closing price on Tuesday. It's important to remember, though, that Aptose's results were from an early stage study. There's still a long way to go for luxeptinib. Positive early data doesn't always translate to success in later-stage clinical testing. Now what Aptose has escalated to the 600 milligram twice-per-day dosing of luxeptinib in its phase 1 study. It's also continuing to enroll additional patients. The company plans to present complete and updated data at the European Hematology Association meeting in June. 10 stocks we like better than Aptose BiosciencesWhen investing geniuses David and Tom Gardner have a stock tip, it can pay to listen. After all, the newsletter they have run for over a decade, Motley Fool Stock Advisor, has tripled the market.* David and Tom just revealed what they believe are the ten best stocks for investors to buy right now... and Aptose Biosciences wasn't one of them! That's right -- they think these 10 stocks are even better buys. See the 10 stocks *Stock Advisor returns as of February 24, 2021 Keith Speights has no position in any of the stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy.Source