NEW YORK – Panbela Therapeutics on Monday said it will work with Moffitt Cancer Center to test the ability of eflornithine to boost STK11-mutant non-small cell lung cancer patients' responses to checkpoint inhibition in a Phase I/II trial.
Eflornithine, an inhibitor of the enzyme ornithine decarboxylase, is designed to enhance immunotherapy treatment, and in the planned Phase I/II trial, Panbela and Moffitt will evaluate the activity of eflornithine with Merck's Keytruda (pembrolizumab). Researchers expect to report data from the Phase I portion of the trial by the end of this year and begin efficacy evaluations in the Phase II portion by early 2024.
The partners see the present trial as an opportunity to establish proof of concept for modulating the immune system using polyamines and standard-of-care therapies. "If the trial is successful, it opens the door for combining polyamine targeted therapies, such as eflornithine and ivospemin, with checkpoint inhibitors in other tumor types where response rates have been poor, or even improve upon reasonable response rates," Panbela CEO Jennifer Simpson said in a statement. "It would also open the possibility of exploring combinations of eflornithine and ivospemin with other immunotherapies, such as CAR T therapy."
Panbela is also studying eflornithine as a treatment for neuroblastoma in a Phase II study and in combination with the nonsteroidal anti-inflammatory drug sulindac as a way to reduce the risk of colon cancer in a Phase III trial. In preclinical studies, the firm is exploring eflornithine in cancers that are nonresponsive to PD-1 inhibitors.