BACKGROUND
Alterations in the gene encoding fibroblast growth factor receptor (FGFR) are common in urothelial carcinoma and may be associated with lower sensitivity to immune interventions. Erdafitinib, a tyrosine kinase inhibitor of FGFR1–4, has shown antitumor activity in preclinical models and in a phase 1 study involving patients with FGFR alterations.

METHODS
In this open-label, phase 2 study, we enrolled patients who had locally advanced and unresectable or metastatic urothelial carcinoma with prespecified FGFR alterations. All the patients had a history of disease progression during or after at least one course of chemotherapy or within 12 months after neoadjuvant or adjuvant chemotherapy. Prior immunotherapy was allowed. We initially randomly assigned the patients to receive erdafitinib in either an intermittent or a continuous regimen in the dose-selection phase of the study. On the basis of an interim analysis, the starting dose was set at 8 mg per day in a continuous regimen (selected-regimen group), with provision for a pharmacodynamically guided dose escalation to 9 mg. The primary end point was the objective response rate. Key secondary end points included progression-free survival, duration of response, and overall survival.

RESULTS
A total of 99 patients in the selected-regimen group received a median of five cycles of erdafitinib. Of these patients, 43% had received at least two previous courses of treatment, 79% had visceral metastases, and 53% had a creatinine clearance of less than 60 ml per minute. The rate of confirmed response to erdafitinib therapy was 40% (3% with a complete response and 37% with a partial response). Among the 22 patients who had undergone previous immunotherapy, the confirmed response rate was 59%. The median duration of progression-free survival was 5.5 months, and the median duration of overall survival was 13.8 months. Treatment-related adverse events of grade 3 or higher, which were managed mainly by dose adjustments, were reported in 46% of the patients; 13% of the patients discontinued treatment because of adverse events. There were no treatment-related deaths.

CONCLUSIONS
The use of erdafitinib was associated with an objective tumor response in 40% of previously treated patients who had locally advanced and unresectable or metastatic urothelial carcinoma with FGFR alterations. Treatment-related grade 3 or higher adverse events were reported in nearly half the patients. (Funded by Janssen Research and Development; BLC2001 ClinicalTrials.gov number, NCT02365597.)

Authors: 
Yohann Loriot, M.D., Andrea Necchi, M.D., Se Hoon Park, M.D., Jesus Garcia-Donas, M.D., Robert Huddart, M.C.R.P., Earle Burgess, M.D., Mark Fleming, M.D., Arash Rezazadeh, M.D., Begoña Mellado, M.D., Sergey Varlamov, M.D., Monika Joshi, M.D., Ignacio Duran, M.D., et al., for the BLC2001 Study Group*

Author Affiliations
From Gustave Roussy, INSERM Unité 981, Université Paris-Sud, Université Paris-Saclay, Villejuif, France (Y.L.); Fondazione IRCCS Istituto Nazionale dei Tumori, Milan (A.N.); Sungkyunkwan University Samsung Medical Center, Seoul, South Korea (S.H.P.); Genitourinary and Gynecological Cancer Unit, Centro Integral Oncológico Clara Campal, Madrid (J.G.-D.), Hospital Clinic Institut d’Investigacions Biomèdiques August Pi i Sunyer, University of Barcelona, Barcelona (B.M.), and Hospital Universitario Marques de Valdecilla, Santander (I.D.) — all in Spain; the Institute of Cancer Research, Sutton, London (R.H.); the Levine Cancer Institute, Atrium Health, Charlotte, NC (E.B.); Virginia Oncology Associates, US Oncology Research, Norfolk (M.F.); Norton Healthcare, Louisville, KY (A.R.); the Altai Regional Cancer Center, Barnaul, Russia (S.V.); the Penn State Cancer Institute, Hershey (M.J.), and Janssen Research and Development, Spring House (B.Z., A.S.-W., A.O., A.A.) — both in Pennsylvania; Weill Cornell Medical College, New York (S.T.T.); University of Iowa Hospitals and Clinics, Holden Comprehensive Cancer Center, Iowa City (Y.Z.); Janssen Research and Development, Beerse, Belgium (K.S., P.D.P.); and the University of Texas M.D. Anderson Cancer Center, Houston (A.O.S.-R.).

Loriot, Y., Necchi, A., Park, S., Garcia-Donas, J., Huddart, R., & Burgess, E. et al. (2019). Erdafitinib in Locally Advanced or Metastatic Urothelial Carcinoma. New England Journal Of Medicine381(4), 338-348. doi: 10.1056/nejmoa1817323

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