This article has been updated to note that Portage is studying PORT-3 in a Phase I trial, not Phase I/II.
NEW YORK – Westport, Connecticut-based Portage Biotech on Thursday began the first human study of its invariant natural killer T-cell agonist, PORT-3, in patients with advanced or metastatic solid tumors that express NY-ESO-1.
The drug is a coformulation of the invariant natural killer T-cell agonist and a tumor-specific antigen targeting NY-ESO-1. The Phase I dose escalation study, called PRECIOUS-01, will evaluate PORT-3 at three dose levels in about 15 participants. Study participants are being screened for NY-ESO-1 expression using immunohistochemistry.
Researchers will use an IHC assay to measure participants' immune responses and determine the composition of immune cell subsets before and after treatment with PORT-3 to establish the recommended Phase II dose. They will also measure the immunological responses in blood to determine the functional response of invariant natural killer T cells and T cells.
Portage is currently developing two invariant natural killer T-cell agonists, PORT-2 and PORT-3. "Preclinical studies of both compounds have shown that treatment can lead to a broad reprogramming of the immune system," Portage CEO Ian Walters said in a statement. "We are excited to begin first-in-human trials of PORT-3 to test the proof-of-concept of this approach. If the trial is successful with NY-ESO-1, it will open the door to a multitude of opportunities to design more formulations with other tumor-specific antigens."
The PRECIOUS-01 trial is funded by the EU Horizon 2020 program and recruitment has begun at Radboud University in the Netherlands.