NEW YORK – Tempest Therapeutics announced Thursday that the investigational new drug application for TPST-1495 has been accepted by the US Food and Drug Administration. The company will now initiate a Phase Ia/Ib clinical trial in solid tumors, with a focus on patients with microsatellite stable colorectal cancer.
TPST-1495 is a first-in-human investigational agent that inhibits prostaglandin receptors EP2 and EP4, which have been strongly implicated in colorectal cancer.
The dose escalation phase of the trial will assess the safety, tolerability, and preliminary anti-tumor activity of TPST-1495 as a monotherapy and in combination with a checkpoint inhibitor. In the expansion cohort, additional patients will be enrolled at the maximum tolerated dose.
In a preclinical study presented at the 2019 Society for Immunotherapy of Cancer annual meeting in November, researchers from Tempest showed that TPST-1495 induced anti-tumor immune responses and significant tumor regression when administered as a single agent in two different mouse models of colon cancer. Additionally, TPST-1495 combined with a PD1-inhibitor stopped tumor progression in mice.
Tempest plans to study TPST-1495 in a broad range of prostaglandin-driven tumors, and CEO Tom Dubensky highlighted that the drug's ability to block both EP2 and EP4 receptors is a mechanism that is unique among other agents attempting to target this pathway.
"Although the clinical trial will allow participation of patients with any solid tumor histology, Tempest intends to focus evaluation of TPST-1495 in patients with microsatellite stable colorectal cancer given the mechanism of action of this first-in-human investigational agent," the firm said in a statement.
Additionally, Tempest announced that Lyfe Capital and Rock Springs Capital Management have made equity investments in the firm but did not disclose the funding amount. The company plans to use the funds to continue studying TPST-1495 and its PPAR alpha antagonist TPST-1120.