Pierre Fabre Laboratories, a global player in oncology, and Scorpion Therapeutics, a clinical-stage oncology company specializing in cancer treatment by redefining the frontier of precision medicine, has 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 targeting epidermal growth factor receptor Exon 19 or 21 mutations with the co-occurring C797S mutation, a known resistance mechanism to 3rd 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 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 geography1,2,3.
“We are eager to begin the clinical evaluation of PFL-241/STX-241, our mutant-selective 4th 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.”
PFL-241/STX-241 is an oral treatment designed to selectively inhibit the C797S resistance mutation co-occurring with EGFR exon 19 deletion or exon 21 mutation (double mutant). Those double mutantsare emerging as an on-target resistance mechanism in a subset of NSCLC patients. Most recent data suggest that the C797S mutation emerges in approximately 12.5%4-8 of patients undergoing therapy with 3rd generation EGFR inhibitors. There are currently no approved therapeutic options for patients who develop this “double mutant” EGFR NSCLC.
“The initiation of the second clinical trial in partnership with Pierre Fabre Laboratories is an important milestone as we work together to enable the rapid, global advancement of our next-generation EGFR inhibitors for difficult-to-treat NSCLC patients,” said Mark Chao, chief medical officer of Scorpion. “PFL-241/STX-241 is a novel, CNS-penetrant and highly potent and selective treatment option for patients who develop ‘double mutant’ disease for which there is currently no approved treatment, and it’s a pleasure to partner with Pierre Fabre Laboratories, a company who shares our commitment to bringing innovative treatments to this underserved patient population. We look forward to demonstrating how PFL-241/STX-241’s differentiated preclinical profile translates into clinical benefit for patients.”
