Shares of Aptose Biosciences (APTO -5.15%) 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).
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."
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.
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.