What is Erdafitinib?
Erdafitinib is an oral kinase inhibitor that targets fibroblast growth factor receptors (FGFRs), specifically FGFR1-4. It is primarily used in the treatment of certain types of cancer, most notably advanced or metastatic urothelial carcinoma, a type of bladder cancer. Erdafitinib was approved by the FDA in April 2019, marking a significant milestone in personalized cancer therapy.
Mechanism of Action
Erdafitinib works by inhibiting the kinase activity of FGFRs. FGFRs play a critical role in cell proliferation, differentiation, and survival. Mutations, amplifications, or overexpression of FGFRs can lead to oncogenesis. By blocking these receptors, erdafitinib disrupts the signaling pathways that promote tumor growth and survival, thereby exerting its anti-cancer effects.Indications
Erdafitinib is indicated for the treatment of patients with locally advanced or metastatic urothelial carcinoma who have susceptible FGFR3 or FGFR2 genetic alterations. This indication is contingent upon the progression of the disease during or following platinum-based chemotherapy. The presence of FGFR genetic alterations should be confirmed using an FDA-approved companion diagnostic test.Administration and Dosage
Erdafitinib is administered orally. The starting dose is typically 8 mg once daily, with the possibility of increasing to 9 mg daily based on serum phosphate levels and patient tolerance. The drug can be taken with or without food, but it is essential to maintain a consistent schedule to optimize efficacy.Side Effects
Like most cancer treatments, erdafitinib comes with potential side effects. Common adverse reactions include hyperphosphatemia, stomatitis, fatigue, increased serum creatinine, diarrhea, and dry eyes. More severe side effects can include ocular disorders such as central serous retinopathy and retinal pigment epithelial detachment, which necessitate regular ophthalmologic monitoring.Drug Interactions
Erdafitinib may interact with other medications that are CYP3A4 inhibitors or inducers, as these can affect its metabolism. Patients should inform their healthcare providers about all medications they are taking, including over-the-counter drugs and supplements, to avoid potential interactions.Contraindications
Erdafitinib is contraindicated in patients with a history of severe hypersensitivity to the drug or any of its components. Caution is also advised in patients with pre-existing ocular conditions or those at risk of developing hyperphosphatemia.Monitoring and Follow-up
Patients receiving erdafitinib require regular monitoring to manage side effects and ensure optimal efficacy. This includes periodic blood tests to monitor phosphate and creatinine levels, as well as regular eye exams to detect any early signs of ocular toxicity.Clinical Trials and Research
Ongoing research and clinical trials are exploring the efficacy of erdafitinib in other cancers with FGFR alterations, such as cholangiocarcinoma and certain types of lung cancer. These studies aim to expand the use of this targeted therapy and improve outcomes for a broader range of cancer patients.Patient Education and Support
Patients should be educated about the importance of adherence to their medication regimen and the need for regular follow-up appointments. Support services, including counseling and patient advocacy groups, can provide additional resources to help manage the physical and emotional challenges of cancer treatment.
