The US Food and Drug Administration has granted orphan drug designation (ODD) to Tempest Therapeutics' oral, selective peroxisome proliferator-activated receptor alpha (PPAR-α) antagonist amezalpat (TPST-1120), for individuals with hepatocellular carcinoma (HCC).
The ODD was awarded following positive outcomes from a randomised Phase Ib/II clinical study.
In the study, the therapy was assessed in combination with the standard-of-care atezolizumab and bevacizumab, compared to atezolizumab and bevacizumab alone. The findings demonstrated a six-month ‘improvement’ in median overall survival (OS) for subjects treated with the combination therapy.
The hazard ratio (HR) was reported to be 0.65, and an objective response rate (ORR) of 30% versus 13% was observed in ‘favour’ of the therapy arm.
Additionally, the survival benefit of adding the therapy was consistent across key sub-populations, including subjects with programmed cell death ligand 1 (PD-L1) negative disease, as well as β-catenin mutated disease.
These findings align with the proposed mechanism of action for the therapy that involves targeting malignant cells and modulating immune suppressive cells and angiogenesis within the microenvironment of the tumour.
The positive data from the randomised study are supported by further ‘encouraging outcomes’ from a Phase I trial in subjects with heavily pretreated advanced solid tumours.
Tempest R&D head and chief medical officer Sam Whiting said: “Receiving orphan drug designation for amezalpat to treat HCC underscores the critical need for new treatment options for patients suffering from this historically hard-to-treat disease.
“Tempest is dedicated to developing groundbreaking cancer treatments that will improve patients’ lives, and with broad agreement in hand from both the FDA and EMA, the team continues to prepare for a pivotal Phase III study for amezalpat in first-line HCC patients.”
Hepatocellular carcinoma is a rapidly progressing cancer that occurs in the liver.
Last October, Tempest announced a collaboration with Roche to further assess amezalpat in conjunction with atezolizumab and bevacizumab in a pivotal Phase III trial for unresectable or metastatic HCC. As part of the agreement, the company agreed to sponsor and lead the study, while Roche will provide atezolizumab on a global scale.
