Tempest Therapeutics, Inc. (NASDAQ: TPST) had a 48.58% increase in share price last Friday after hours, closing at $12.25. TPST shares surged when the European Medicines Agency (EMA) announced that the company’s investigational medication, amezalpat (TPST-1120), had been granted Orphan Drug Designation (ODD).
Movement Gains Strength in the US and Europe
This further classification from the EMA has already been backed by the U.S. Food and Drug Administration (FDA), which has already given amezalpat both Orphan Drug and Fast Track status.
TPST-1120 can be used to treat hepatocellular carcinoma (HCC), a kind of liver cancer. Amezealpat is an oral selective PPAR⍺ antagonist that targets tumor cells and modifies immune responses.
Tempest Therapeutics’ believe in amezalpat’s therapeutic potential is strengthened by these regulatory recognitions, which also highlight the significant unmet medical need in liver cancer.
Clinical Data Emphasizes the Advantage of Survival
The designations resulted from positive results from a global, randomized Phase 1b/2 clinical study that compared amezalpat with standard therapies—atezolizumab and bevacizumab—versus the standard treatment alone.
Patients receiving the amezalpat regimen demonstrated a six-month extension in median overall survival, with a hazard ratio of 0.65. Importantly, the therapy also showed consistent benefit in patients with PD-L1 negative disease, supporting its dual mechanism of action.
Expanded Research and Strategic Plans
Further validation of amezalpat’s immune-modulatory effects was presented at the 2025 American Association for Cancer Research (AACR) Annual Meeting, underscoring its potential as an innovative cancer therapy.
Additionally, the FDA has issued a “Study May Proceed” letter for a Phase 2 trial involving amezalpat for familial adenomatous polyposis (FAP), led by CP-CTNet and funded by the National Cancer Institute. The research is scheduled to start in 2025.
As part of its efforts to streamline operations and increase shareholder value, Tempest Therapeutics (TPST) also confirmed a headcount reduction that was finished on April 30, 2025, and announced a strategic evaluation of its clinical-stage initiatives to complement its expanding portfolio.
