Shares of microcap oncology company Tempest Therapeutics Inc. (TPST) dropped 59.26% during the trading hours and slipped 10.55% in extended trading on Thursday as investors took a breath after the stock's roughly 40-fold gain on Wednesday.
Trading in Tempest shares was halted briefly for volatility shortly after the market opened Thursday.
The stock's 3,973% surge Wednesday started after Tempest released new study results for its investigational treatment TPST-1120 in patients with liver cancer and announced a limited-duration stockholder-rights plan, or "poison pill," which the company said would help shareholders realize the long-term value of their investment.
The drug candidate, when combined with the Roche Holding AG (RHHBY) monoclonal antibodies Tecentriq and Avastin, showed clinical superiority in treating unresectable or metastatic hepatocellular carcinoma, an aggressive form of liver cancer, Tempest said in a release Wednesday.
Given the high mortality rates associated with this type of cancer, "we're enthusiastic about the potential to move TPST-1120 forward," Tempest President and CEO Stephen Brady said on a call with analysts Wednesday. "We have thought through multiple approval strategies and look forward to advancing our discussions with potential partners who share the vision for TPST-1120."
As the company looks to move the drug into a larger pivotal study, it's seeking a partner in part to control costs, Brady said on the call. "If Tempest were to do this 100% alone, pay for everything, including companion drugs, you're looking at north of $100 million to do this study," he said.
Tempest shares are up 277% in the year to date, while the S&P 500 SPX has gained 14.2%.
