Erdanat-4 — Erdafitinib 4 mg Tablets, 28 Tablets

Erdanat-4 is supplied in a modern solid oral dosage form for internal administration:

• Presentation and Packaging: 1 original white high-density polyethylene (HDPE) bottle with a child-resistant closure containing 28 film-coated tablets. Each bottle, along with a comprehensive package leaflet, is enclosed in an outer cardboard box featuring Natco security seals.
• Active Ingredient:
  • Erdafitinib — 4 mg in each film-coated tablet.
• Excipients: Mannitol, microcrystalline cellulose, croscarmellose sodium, magnesium stearate, colloidal anhydrous silica, hydroxypropyl methylcellulose (hypromellose), titanium dioxide, macrogol/polyethylene glycol, purified talc, colorants (red iron oxide / yellow iron oxide).

Pharmacodynamics: Erdafitinib is a small-molecule, oral pan-inhibitor of Fibroblast Growth Factor Receptor (FGFR1, FGFR2, FGFR3, and FGFR4) tyrosine kinases. In cancer cells harboring FGFR alterations (such as FGFR3 point mutations R248C, S249C or FGFR3-TACC3 fusions), constitutive activation of downstream signaling pathways (RAS-RAF-MEK-ERK and PI3K-AKT) drives malignant transformation. Erdafitinib binds to the ATP-binding site of the FGFR kinase domain, inhibiting receptor autophosphorylation, blocking downstream signal transduction, reducing tumor cell proliferation, and inducing apoptosis.

Pharmacokinetics: Following oral administration, Erdafitinib is rapidly absorbed from the gastrointestinal tract, reaching peak plasma concentration (Cmax) in approximately 2 to 4 hours. Food co-administration does not exert a clinically meaningful effect on absorption. Plasma protein binding (primarily to albumin and alpha-1-acid glycoprotein) is approximately 99.5%. Erdafitinib undergoes extensive hepatic metabolism mediated predominantly by CYP2C9 and CYP3A4 enzymes. The terminal elimination half-life (T1/2) is approximately 50 to 60 hours, supporting steady-state plasma concentrations with once-daily dosing. Elimination occurs primarily via feces (approx. 69%) and urine (approx. 19%).

Erdanat-4 is indicated for the treatment of adult patients under the following clinical conditions:

• 🔹 Locally Advanced or Metastatic Urothelial Carcinoma: Monotherapy for the treatment of adult patients with unresectable, locally advanced, or metastatic urothelial carcinoma that has susceptible FGFR3 or FGFR2 genetic alterations (determined by an FDA-approved diagnostic test).
• 🔹 Disease Progression After Prior Systemic Therapy: Patients whose disease has progressed during or following at least one line of prior platinum-containing chemotherapy (including within 12 months of neoadjuvant or adjuvant chemotherapy) or prior targeted/immunotherapy.

Administration of Erdanat-4 must be conducted under the supervision of a physician experienced in cancer therapies:

• 👨‍⚕️ Initial Dosing Regimen: The recommended starting dose of Erdafitinib is 8 mg once daily (two Erdanat-4 4 mg tablets) taken orally at the same time each day.
• 👨‍⚕️ Dose Escalation Based on Serum Phosphate: Serum phosphate levels should be evaluated 14 to 21 days after initiating treatment. If serum phosphate is <5.5 mg/dL (1.78 mmol/L) and no treatment-related adverse reactions are present, increase the dose to 9 mg once daily (three 3 mg tablets). If toxicity occurs, reduce the dose (e.g., to 6 mg or 4 mg once daily using 1 Erdanat-4 tablet).
• 👨‍⚕️ Administration Instructions: Tablets should be swallowed whole with a full glass of water. Do not crush, chew, or split tablets. May be taken with or without food.
• 🥤 Treatment Duration: Therapy should continue until disease progression or unacceptable toxicity occurs.

Erdanat-4 is strictly contraindicated in patients with the following conditions:

• ❌ Known hypersensitivity or severe allergic reaction to Erdafitinib or any of the excipients in the tablet formulation.
• ❌ Pregnancy and breastfeeding (high risk of embryo-fetal toxicity and teratogenicity).
• ❌ Pediatric population under 18 years of age (safety and efficacy have not been established).
• ❌ Severe hepatic impairment (Child-Pugh Class C).
• ❌ Severe renal impairment (creatinine clearance <30 mL/min or end-stage renal disease on hemodialysis).

Erdafitinib is extensively metabolized by hepatic cytochrome P450 enzymes, requiring clinical vigilance during concomitant drug administration:

• ⚠️ Strong CYP2C9 and CYP3A4 Inhibitors: Co-administration with ketoconazole, itraconazole, or clarithromycin increases Erdafitinib plasma exposure, raising toxicity risk. Avoid concurrent use or adjust Erdanat-4 dosage.
• ⚠️ Strong CYP2C9 and CYP3A4 Inducers: Rifampin, phenytoin, carbamazepine, and St. John's wort significantly decrease Erdafitinib plasma levels, reducing clinical efficacy. Concomitant use should be avoided.
• ⚠️ P-glycoprotein (P-gp) Substrates: Erdafitinib may inhibit intestinal P-gp. Co-administration with digoxin requires therapeutic drug monitoring.
• ⚠️ Phosphate-Altering Agents: Avoid co-administration of agents that alter serum phosphate levels prior to the initial phosphate evaluation window (Days 14–21).

Erdanat-4 exhibits potent teratogenic and embryo-fetal lethal properties:

• 🤰 Pregnancy: Erdanat-4 is contraindicated during pregnancy. It can cause fetal harm when administered to a pregnant woman. Pregnancy testing is mandatory for females of reproductive potential prior to initiating treatment.
• 🛡️ Contraception: Females of reproductive potential must use effective contraception during Erdanat-4 therapy and for 1 month after the final dose. Male patients with female partners of reproductive potential must use effective barrier contraception during treatment and for 1 month after the last dose.
• 🤱 Lactation: It is unknown whether Erdafitinib is excreted in human milk. Breastfeeding must be discontinued during treatment with Erdanat-4 and for 1 month following the last dose.

Treatment with Erdanat-4 requires routine clinical monitoring to manage potential adverse reactions:

• 🔴 Ocular Disorders: Central serous retinopathy / retinal pigment epithelium detachment (dry eyes, blurred vision, visual field defects). Routine ophthalmologic examinations are required.
• 🟡 Metabolic Disturbances: Hyperphosphatemia (elevated serum phosphate levels, serving as a pharmacodynamic marker), hyponatremia, hypophosphatemia.
• 🟠 Dermatologic Reactions: Palmar-plantar erythrodysesthesia syndrome (hand-foot syndrome), dry skin, alopecia, nail disorders (onycholysis, paronychia).
• 🟢 Gastrointestinal Effects: Stomatitis (mucosal inflammation), dry mouth, diarrhea, nausea, decreased appetite, dysgeusia (taste alteration).
• 🔵 Laboratory & General Symptoms: Increased ALT, AST, alkaline phosphatase levels; fatigue, asthenia, arthralgia, and myalgia.

Clinical data regarding acute Erdanat-4 overdose are limited:

• Symptoms: Administration of higher than recommended doses exacerbates pharmacological side effects, primarily severe hyperphosphatemia, extensive stomatitis, ocular dryness, and severe nail dystrophy.
• Management: There is no specific antidote for Erdafitinib. In case of overdose, immediately discontinue Erdanat-4, perform gastric lavage if recently ingested, administer oral phosphate binders (for hyperphosphatemia), and initiate supportive care. Hemodialysis is ineffective due to high plasma protein binding.

Storage instructions for Erdanat-4 tablets:

• Temperature Control: Store in the original container at temperatures not exceeding 25 °C in a dry place protected from direct sunlight.
• Moisture Protection: Keep the bottle tightly closed after opening. Do not remove the desiccant canister from the bottle.
• Safety: Store out of the reach and sight of children and domestic animals.
• Shelf Life: 2 years (24 months) from the date of manufacture. Do not use after the expiration date printed on the package.

Verification guidelines for genuine Erdanat-4 tablets manufactured by Natco Pharma Ltd.:

• Packaging & Typography: The outer carton and HDPE bottle display Natco's official corporate styling. Crisp text prominently displays Erdanat®-4 (featuring a red numeral "4" and green geometric triangular branding at the base), Erdafitinib Tablets 4 mg, quantity 28 Tablets, and For oral use.
• Manufacturer Logo: The official oval NATCO logo (red lettering inside a blue oval) is clearly printed on both the bottle label and carton front, accompanied by a large green and red geometric emblem.
• Batch Details: The carton side flap and bottle label feature laser-printed or inkjet details: Batch No., Mfg Date, Expiry Date, and Maximum Retail Price (M.R.P.).
• Tamper-Evident Seal: The HDPE bottle features a child-resistant cap with a tamper-evident breakable ring and an inner induction foil seal over the bottle neck.