Abstract CT325: First in human study of JNJ-42756493, a potent pan fibroblast growth factor receptor (FGFR) inhibitor in patients with advanced solid tumors
Authors: Dienstmann Rodrigo , Bahleda Rastilav , Adamo Barbara , Rodon Jordi , Varga Andrea , Gazzah Anas , Platero Suso , Smit Hans , Perera Timothy , Zhong Bob , Stuyckens Kim , Elsayed Yusri , Takimoto Chris , Peddareddigari Vijay , Tabernero Josep , Luo Feng Roger , Soria Jean-Charles 
Published: May 2015

Abstract
Background: JNJ-42756493 is an FGFR 1, 2, 3, and 4 inhibitor with nanomolar affinity, orally bioavailable, and has demonstrated a broad spectrum antitumor activity in cell line, xenograft and patient-derived explant models with abnormality in FGFR signaling pathway such as FGFR gene amplification, mutation and translocation.
Methods: A multipart phase 1 first in human study of JNJ-42756493 was initiated in advanced solid tumor patients (NCT01962532) including, Part 1 dose-escalation to determine the recommended phase 2 dose (RP2D) based on safety, pharmacokinetic, and pharmacodynamic data; Part 2 biopsy cohort to confirm the RP2D and Part 3 expansion phase to evaluate anti-tumor activity in NSCLC, SCLC, Breast cancer and other solid tumor patients with FGFR gene amplification, mutation or translocation at RP2D. Multiple biomarkers from tissue (including phospho-FGFR, phospho-Erk and phospho-S6) and serum (phosphate, calcium, Vitamin D, PTH and FGF23) were also assessed in the study.
Results: At data cut-off (22 October 2013), total of 28 patients had been treated at 5 dose levels (0.5, 2, 4, 6 and 9 mg daily continuously) in Part 1 of the study. JNJ-42756493 appeared safe, did not generate any dose-limiting toxicities or any drug related severe adverse events. One patient from 4 mg cohort died after receiving 6 doses in Cycle 1, autopsy indicated a serious adverse event (SAE) of pulmonary edema which not related to the study drug. The most common adverse events (AEs) were hyperphosphatemia (57%), asthenia (46%), dry mouth (32%), abdominal pain (29%), diarrhea (25%), vomiting (25%), decreased appetite (21%) and constipation (21%). Grade 1 or 2 hyperphosphatemia was managed by co-administration of phosphate lowering therapy and by treatment interruption, other AEs were generally mild to moderate. No clinically significant cardiac safety findings were observed. Pharmacokinetics was linear and predictable with a half-life of ∼50 hours. Dose levels ≥ 6mg achieved plasma concentrations predicted to be efficacious from preclinical experiments. Dose dependent changes in biomarkers including increases in phosphate, FGF23 and calcium and decreases in PTH were observed in blood, evaluation of biomarker response in tissue is ongoing. A bladder cancer patient with lung metastasis harboring a FGFR3-TACC3 translocation treated at 9 mg had a confirmed PR. 9 mg was declared as the first RP2D, but safety evaluation of JNJ-42756493 at higher doses is ongoing.
Conclusions: JNJ-42756493 has excellent pharmaceutical properties and appeared safe with manageable side effects at dose levels that elicit anti-tumor activity.
Citation Format: Rodrigo Dienstmann, Rastilav Bahleda, Barbara Adamo, Jordi Rodon, Andrea Varga, Anas Gazzah, Suso Platero, Hans Smit, Timothy Perera, Bob Zhong, Kim Stuyckens, Yusri Elsayed, Chris Takimoto, Vijay Peddareddigari, Josep Tabernero, Feng Roger Luo, Jean-Charles Soria. First in human study of JNJ-42756493, a potent pan fibroblast growth factor receptor (FGFR) inhibitor in patients with advanced solid tumors. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr CT325. doi:10.1158/1538-7445.AM2014-CT325