axitinib (Inlyta)

Dosing and uses of Inlyta (axitinib)

• Adult
• Pediatric
• Geriatric

 

Adult dosage forms and strengths

tablet

• 1mg
• 5mg

 

Renal Cell Carcinoma

Indicated for treatment of advanced renal cell carcinoma after failure of 1 prior systemic therapy

Initial dose: 5 mg PO q12hr (see Dosage modifications)

 

Dosage modifications

Dose increase or reduction based on individual safety and tolerability

Dose escalation

• Criteria: Tolerated for at least 2 consecutive weeks with no adverse reactions (ie, not exceeding grade 2 toxicities) and are normotensive and not receiving antihypertension medications
• First dose increase: 7 mg PO BID
• Second dose increase: Using the same criteria, may further increase to 10 mg PO BID

Dose reduction or discontinuation

• Hypertension: If persistent hypertension occurs despite antihypertensive medications, reduce dose; discontinue if hypertension is severe and persists despite dose reduction
• Hypertensive crisis: Discontinue axitinib
• Hemorrhage: If any bleeding requires medical intervention, temporarily interrupt axitinib dose
• Surgery: Discontinue at least 24 hr prior to scheduled surgery
• Reversible posterior leukoencephalopathy syndrome: Discontinue axitinib
• Moderate-to-severe proteinuria: Reduce dose or temporarily interrupt treatment
• Strong CYP3A4/5 inhibitors: Avoid coadministration if possible, if axitinib must be coadministered, decrease dose by ~50% and then adjust according to safety and tolerance; if strong CYP3A4/5 inhibitor is discontinued, may increase to prior axitinib dose after waiting 3-5 half-lives of the inhibitor

 

Renal & Hepatic Impairment

Renal impairment

• No dedicated renal impairment trial has been conducted
• Based on population pharmacokinetic analyses, no significant difference in clearance observed in patients with pre-existing mild-to-severe renal impairment

Hepatic impairment

• Mild (Child-Pugh A): No adjustment of initial dose is required
• Moderate (Child-Pugh B): Decrease initial dose by ~50%; subsequent doses can be increased or decreased based on individual safety and tolerability
• Severe (Child-Pugh C): Has not been studied

 

Administration

Administer twice daily approximately 12 hr apart

May be taken with or without food

Swallow whole with a glass of water; do not split, crush, or chew

If patient vomits or misses a dose, an additional dose should not be taken; the next prescribed dose should be taken at the usual time

 

Pediatric dosage forms and strengths

<18 years: Safety and efficacy not established

 

Geriatric dosage forms and strengths

In clinical trials, 34% of participants 65 years or older

No overall differences were observed in the safety or efficacy between elderly and younger patients

No dosage adjustment required in elderly patients

 

Inlyta (axitinib) adverse (side) effects

>10%

Diarrhea (55%)

Hypertension (40%)

Fatigue (39%)

Decreased appetite (34%)

Nausea (32%)

Dysphonia (31%)

Palmar-plantar erythrodysesthesia syndrome (27%)

Weight decreased (25%)

Vomiting (24%)

Asthenia (21%)

Constipation (20%)

Hypothyroidism (19%)

Cough (15%)

Mucosal inflammation (15%)

Arthralgia (15%)

Stomatitis (15%)

Dyspnea (15%)

Abdominal pain (14%)

Headache (14%)

Extremity pain (13%)

Rash (13%)

Proteinuria (11%)

Dysgeusia (11%)

 

1-10%

Dry skin (10%)

Dyspepsia (10%)

Dizziness (9%)

Upper abdominal pain (8%)

Myalgia (7%)

Pruritus (7%)

Dehydration (6%)

Epistaxis (6%)

Hypercalcemia (6%)

Anemia (4%)

Alopecia (4%)

Hemorrhoids (4%)

Hematuria (3%)

Tinnitus (3%)

Increased lipase (3%)

Glossodynia (3%)

Pulmonary embolism (2%)

Rectal hemorrhage (2%)

Hemoptysis (2%)

Erythema (2%)

DVT (1%)

Retinal vein occlusion/thrombosis (1%)

Polycythemia (1%)

TIA (1%)

 

<1%

Reversible posterior leukoencephalopathy syndrome

 

Warnings

Contraindications

None

 

Cautions

Hypertension and hypertensive crisis reported in clinical trials, typically within the first month of treatment; blood pressure increases may appear as early as 4 days after initiating; blood pressure should be well controlled before starting therapy; dosage modification or discontinuation of treatment may be required (see Dosage modification)

Although rare, arterial thromboembolic events (including deaths) reported during clinical trials

Venous thromboembolic events (eg, DVT, PE, retinal vein occlusion, retinal vein thrombosis) reported, including deaths

Hemorrhagic events (eg, cerebral hemorrhage, hematuria, hemoptysis, GI bleeding, melena) may occur

Rare occurrences of GI perforation and fistula formation reported

May cause thyroid dysfunction; monitor thyroid function before initiating and periodically throughout therapy

Stop treatment 24 hr before scheduled surgery

May cause proteinuria; monitor proteinuria before initiating and periodically throughout therapy

Elevated liver enzymes reported; monitor ALT, AST, and bilirubin

Moderate hepatic impairment requires dose reduction (see Dosage modification)

Coadministration with strong CYP3A4/5 inhibitors or inducers should be avoided if possible (see Dosage modifications)

Cardiac failure reported with axitinib use; monitor for signs or symptoms of cardiac failure throughout treatment; may require permanent discontinuation of axitiniB

 

Pregnancy and lactation

Pregnancy category: D; can cause fetal harm when administered to a pregnant woman based on its mechanism of action; axitinib was teratogenic, embryotoxic, and fetotoxic in mice at exposures lower than human exposures at the recommended starting dose

Lactation: Unknown whether distributed in breast milk; because of the potential for serious adverse reactions in nursing infants from axitinib, a decision should be made whether to discontinue breast feeding or to discontinue the drug, taking into account the importance of the drug to the mother

 

Pregnancy categories

A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

NA: Information not available.

 

Pharmacology of Inlyta (axitinib)

Mechanism of action

Multi-targeted tyrosine kinase inhibitor

Inhibits receptor tyrosine kinases including vascular endothelial growth factor receptors (VEGFR)-1, VEGFR-2, and VEGFR-3

 

Absorption

Bioavailability: 58%

Peak Plasma Time: 2.5-4.1 hr

Peak Plasma Concentration: 27.8 ng/mL

AUC: 265 ng•h/mL

 

Distribution

Protein Bound: >99% (mostly to albumin, moderately to alpha1-acid glycoprotein)

Vd: 160 L

 

Metabolism

Metabolized primarily by CYP3A4/5 and to a lesser degree by CYP1A2, CYP2C19, and UGT1A1

Metabolites: Plasma levels detected the N-glucuronide metabolite (50%), sulfoxide metabolite (20%), and 20% unchanged drug

 

Elimination

Half-life: 2.5-6.1

Total body clearance: 38 L/h

Excretion: feces 41% (12% unchanged), urine 23% (as carboxylic acid and sulfoxide metabolites)