Five Prime Therapeutics, Inc., a biotechnology company focused on novel protein therapeutics for the treatment of cancer and inflammatory diseases, provided an update to the ongoing Phase 1b clinical trial, conducted by GSK, on the drug candidate FP-1039/GSK3052230 as a treatment option for squamous non-small cell lung cancer (sqNSCLC) and mesothelioma.
FP-1039 is a protein drug designed to bind FGF (fibroblast growth factor) ligands circulating in the extracellular space. One of these ligands is FGF-2, found in abnormally high levels in the majority of mesothelioma patients. FP-1039 was designed to block these signaling proteins from reaching the FGFR1 (fibroblast growth factor receptor 1) on the surface of tumor cells. If FGFs trigger FGFR1, they can stimulate cancer proliferation and/or angiogenesis. In preclinical tests, conducted by Five Prime Therapeutics, FP-1039 was found to inhibit mesothelioma tumor growth.
The Phase 1b trial was designed as a three-arm study to evaluate the safety, tolerability, dosage, response rate, and duration of response of FP-1039. Arm A includes previously untreated metastatic sqNSCLC, treated in combination with paclitaxel and carboplatin; arm B includes patients with metastatic sqNSCLC that has progressed after previous therapy, to be treated in combination with docetaxel; and arm C includes patients with mesothelioma, for treatment in combination with pemetrexed and cisplatin.
GSK previously presented preliminary data on the efficacy and safety of FP-1039 at the World Conference on Lung Cancer in September 2015. Those results indicated that, in the trial’s arm A, treatment-naïve sqNSCLC patients were responding to the treatment, but arm B in second line sqNSCLC had too few patients enrolled for results, and data from arm C in mesothelioma patients was “immature” and not yet ready for evaluation.
Both companies have now agreed to stop further recruitment of sqNSCLC patients for arms A and B, and to continue enrolling up to 30 mesothelioma patients in arm C. GSK plans to present data at the American Society of Clinical Oncology (ASCO)’s annual meeting in June 2016.
“We are encouraged by the preliminary data we have recently reviewed from the mesothelioma arm of the study and look forward to seeing the results as additional patients are enrolled and followed. The majority of mesothelioma tumors express high levels of FGF-2, so our FGF ligand trap represents a rational therapeutic approach, and patients currently have limited treatment options,” Dr. Lewis T. Williams, president and chief executive officer of Five Prime, said in a company press release. “If we see similar results once we have full, mature data for Arm C, we will seek to regain rights for FP-1039 in the U.S., Canada and the E.U. from GSK, as mesothelioma could represent a potentially attractive market opportunity for Five Prime.”
More information on the clinical trial, including how mesothelioma patients might participate, is available through this link. The study is scheduled to run through October 2016.