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What is Erdafitinib and explain in detail?
Erdafitinib, sold under the brand name Balversa, is an anti-cancer medication. It is a small molecule inhibitor of fibroblast growth factor receptor (FGFR) used for the treatment of cancer. FGFRs are a subset of tyrosine kinases which are unregulated in some tumors and influence tumor cell differentiation, proliferation, angiogenesis, and cell survival. Astex Pharmaceuticals discovered the drug and licensed it to Janssen Pharmaceuticals for further development.Researchers have investigated erdafitinib for safety and efficacy in treatment of bile duct cancer, gastric cancer, non-small cell lung cancer, and esophageal cancer.In March 2018, erdafitinib was granted breakthrough therapy designation by the U.S. Food and Drug Administration (FDA) for treatment of urothelial cancer.In April 2019, erdafitinib was granted approval by the FDA for treatment of metastatic or locally advanced bladder cancer with an FGFR3 or FGFR2 alteration that has progressed beyond traditional platinum-based therapies, subject to a confirmatory trial. The U.S. Food and Drug Administration (FDA) considers it to be a first-in-class medication.

Side effects
Common side effects include increased phosphate level, mouth sores, feeling tired, change in kidney function, diarrhea, dry mouth, nails separating from the bed or poor formation of the nail, change in liver function, low salt (sodium) levels, decreased appetite, change in sense of taste, low red blood cells (anemia), dry skin, dry eyes and hair loss. Other side effects include redness, swelling, peeling or tenderness on the hands or feet (hand foot syndrome), constipation, stomach pain, nausea and muscle pain.Erdafitinib may cause serious eye problems, including inflamed eyes, inflamed cornea (front part of the eye) and disorders of the retina, an internal part of the eye