PFL-241/STX-241 is a highly selective, and potentially best-in-class fourth generation epidermal growth factor receptor ("EGFR") inhibitor

One of two EGFR programs being developed with Scorpion Therapeutics

Pierre Fabre Laboratories, a global player in oncology, and Scorpion Therapeutics, Inc. ("Scorpion"), a pioneering clinical-stage oncology company dedicated to transforming the lives of cancer patients by redefining the frontier of precision medicine, today announced that the first patient has been dosed in a Phase I/II, first-in-human dose-escalation, dose-optimization and dose-expansion trial. This clinical trial evaluates PFL-241/STX-241, a highly differentiated, orally bioavailable, highly selective tyrosine kinase inhibitor ("TKI") targeting epidermal growth factor receptor ("EGFR") Exon 19 or 21 mutations with the co-occurring C797S mutation, a known resistance mechanism to 3^rd generation EGFR inhibitors.

The PFL-241/STX-241 Phase I/II trial is an open label, multi-center study that aims to assess the safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD) and preliminary clinical efficacy of PFL-241/STX-241 as a monotherapy in patients with locally advanced or metastatic non-small cell lung cancer ("NSCLC") harboring EGFR Exon 19 or 21 mutations with the co-occurring C797S mutation.

NSCLC is the most common form of lung cancer and EGFR mutations are one of its most common disease drivers, occurring in up to 38 percent of tumors, depending on geography.

"We are eager to begin the clinical evaluation of PFL-241/STX-241, our mutant-selective 4^th generation EGFR inhibitor, a molecule with differentiated properties that we believe has the potential to become a best-in-class therapeutic option for patients developing resistance to current targeted therapy," said Francesco Hofmann, Head of Research and Development for Medical Care at Pierre Fabre Laboratories. "The initiation of this clinical trial highlights our team's engagement and execution in strong partnership with Scorpion Therapeutics, and we look forward to demonstrating how patients could potentially benefit from this targeted therapy."