pazopanib (Votrient)
Classes: Antineoplastics, Tyrosine Kinase Inhibitor; Antineoplastics, VEGF Inhibitor
Dosing and uses of Votrient (pazopanib)
Adult dosage forms and strengths
tablet
- 200mg
- 400mg
Advanced Renal Cell Carcinoma
800 mg PO qDay on empty stomach (at least 1 hr ac or 2 hr pc)
Soft Tissue Sarcomas
800 mg PO qDay on empty stomach (at least 1 hr ac or 2 hr pc)
Indication: Treatment of advanced soft tissue sarcoma in patients who have received prior chemotherapy
Limitations of use: Efficacy not demonstrated in adipocytic soft tissue sarcoma or gastrointestinal stromal tumors
Ovarian Cancer (Orphan)
Orphan designation for treatment of ovarian cancer
Orphan sponsor
- GlaxoSmithKline
Dosage modification
In RCC, the initial dose reduction should be 400 mg, and additional dose decrease or increase should be in 200 mg steps based on individual tolerability
Coadministration with strong CYP3A4 inhibitors: Avoid if possible, but if coadministration is warranted, decrease pazopanib dose to 400 mg/day; further dose reduction may be needed if adverse effects occur
Coadministration with strong CYP3A4 inducers: Should not use pazopanib in patients unable to avoid use of strong CYP3A4 inducers (eg, rifampin)
Renal Impairment
Renal impairment: No dosage adjustment required
Hepatic Impairment
Billirubin <1.5 x ULN or ALT >ULN: No dosage adjustment required
Billirubin ≥1.5-3 x ULN: Decreased dose to 200 mg PO qDay
Billirubin >3 x ULN: Not recommended
Administration
Do not crush or chew (increases bioavailability and absorption rate, with possible increased toxicity)
Food also increases bioavailability, possibly resulting in increased toxicity
Pediatric dosage forms and strengths
Safety and efficacy not established; not indicated for use in pediatric patients
Based on its mechanism of action, pazopanib may have severe effects on organ growth and maturation during early postnatal development, particularly in children younger than 2 years
Votrient (pazopanib) adverse (side) effects
>10%
ALT (SGPT) level raised (all grades, 53%; grade 3, 10%; grade 4, 2% )
AST/SGOT level raised (all grades, 53%; grade 3, 7%; grade 4, less than 1% )
Diarrhea (52%)
Increased glucose (41%)
Hypertension (40%)
Hair depigmentation (38%)
Leukopenia (all grades, 37%; grade 3, 0%; grade 4, 0% )
Increased bilirubin level (all grades, 36%; grade 3, 3%; grade 4, less than 1% )
Neutropenia (all grades, 34%; grade 3, 1%; grade 4, less than 1% )
Phosphorous decreased (34%)
Thrombocytopenia (all grades, 32%; grade 3, less than 1%; grade 4, less than 1% )
Lymphocytopenia (all grades, 31%; grade 3, 4%; grade 4, less than 1% )
Sodium decreased (31%)
Magnesemium decreased (26%)
Nausea (26%)
Weakness (22%)
Vomiting (21%)
Anorexia (22%)
Fatigue (19%)
Bradycardia (19%)
Hemorrhage (all grades, 13% to 16%; grade 3 to 5, 2%)
Myocardial dysfunction (ie, ≥15% decline in LVEF from baseline or ≥10% with baseline below normal) (11-13%)
Abdominal pain (11%)
1-10% (select)
Headache (10%)
Proteinuria (9%)
Weight loss (9%)
Alopecia (8%)
Dysgeusia (8%)
Rash (8%)
Hypothyroidism (4% to 7% )
Palmar-plantar erythrodysesthesia (6%)
Chest pain (5%)
Dyspepsia (5%)
Skin depigmentation (3%)
Prolonged QT interval (<2%)
Hepatotoxicity (1%-2%)
Facial edema (1%)
Rectal hemorrhage (1%)
Transient ischemic attack (1%)
Hemorrhagic death (0.9%-1%)
<1%
Cardiac dysfunction (eg, decreased LVEF, CHF) (0.6%) Congestive heart failure (0.5%)
Torsades de pointes
Cerebrovascular accident
Pancreatitis
Frequency not defined
Myocardial infarction
Gastrointestinal fistula
Gastrointestinal perforation
Postmarketing Reports
Gastrointestinal disorders: Pancreatitis
Musculoskeletal and connective tissue disorders: Arthralgia, muscle spasms
Eye disorders: Retinal detachment/tear
Interstitial lung disease
Warnings
Black box warnings
Severe hepatotoxicity including fatalities reported in postmarketing survaillance
Contraindications
Hypersensitivity
Cautions
Severe hepatotoxicity, including fatalities, has been reported
Increases in serum transaminase levels and bilirubin observed; severe and fatal hepatotoxicity has occurred; measure liver chemistries before initiation of treatment and regularly during treatment
Patients >65 years are at greater risk for hepatotoxicity
Hypertension, including hypertensive crisis have occurred; blood pressure should be well controlled prior to initiating therapy; monitor blood pressure within one week after starting therapy and frequently thereafter
Rare occurrences of QT prolongation and torsades de pointes reported during clinical trials; consider monitoring electrocardiograms and electrolytes
Thrombotic microangiopathy (TMA), including thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS) observed; permanently discontinue therapy if TMA occurs
Hematologic parameter alterations (ie, leukopenia, neutropenia, thrombocytopenia, lymphocytopenia) reported in 31-37%
Coadministration with strong CYP3A4 inhibitors (eg, ketoconazole, ritonavir, clarithromycin, grapefruit juice) may increase pazopanib serum levels
CYP3A4 inducers (eg, rifampin, carbamazepine) decrease pazopanib serum levels
Gastrointestinal perforation or fistula reported; fatal perforation events have occurred; use with caution in patients at risk for gastrointestinal perforation or fistula
Events of cardiac dysfunction (decreased LVEF and congestive heart failure) have been observed; baseline and periodic evaluation of LVEF recommended in patients at risk of cardiac dysfunction
Avoid concomitant use with drugs that raise gastric pH; consider short-acting antacids in place of proton pump inhibitors (PPIs) and H2 receptor antagonists; separate antacid and pazopanib dosing by several hr
Reversible posterior leukoencephalopathy syndrome (RPLS) has been observed and can be fatal; permanently discontinue therapy in patients developing RPLs
Interruption of therapy recommended in patients undergoing surgical procedures
Hypothyroidism may occur; monitoring of thyroid function tests recommended
Monitor urine protein. interrupt treatment for 24-hr urine protein ≥3 g and discontinue for repeat episodes despite dose reductions
Serious infections (with or without neutropenia), some with fatal outcome, reported; monitor for signs and symptoms and treat active infection promptly; interrupt or discontinue therapy
Interstitial lung disease/pneumonitis reported; monitor patients for pulmonary symptoms indicative of ILD/pneumonitis and discontinue therapy in patients developing ILD or pneumonitis
Fatal hemorrhagic events reported; therapy has not been studied in patients who have a history of hemoptysis, cerebral, or clinically significant gastrointestinal hemorrhage in the past 6 months and should not be used in those patients
Arterial thromboembolic events that can be fatal reported; use with caution in patients who are at increased risk for these events
Venous thromboembolic events (VTE) reported, including fatal pulmonary emboli (PE); monitor for signs and symptoms of VTE and PE; monitor for signs and symptoms of VTE and Pe
Animal studies have shown therapy can severely affect organ growth and maturation during early post-natal development; safety and effectiveness in pediatric patients not established
Can cause fetal harm when administered to a pregnant woman; advise females of reproductive potential of the potential hazard to fetus and to use effective contraception during treatment and for at least 2 weeks after last dose
Pregnancy and lactation
Pregnancy category: d
Lactation: Unknown whether distributed in breast milk, do not nurse
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 Votrient (pazopanib)
Mechanism of action
Multikinase inhibitor (including VEGF & PDGF receptor tyrosine kinases) some of which are implicated in tumor growth, angiogenesis, & metastasis
Absorption
Peak Plasma Time: 2-4 hr
Peak Plasma Concentration: 58.1 mcg/mL
AUC: 1,037 hr•mcg/mL
Cmax and AUC increased 2-fold with food; also increased if table crushed
Distribution
Protein Bound: >99%
Pgp substrate
Metabolism
Metabolized by CYP3A4 (major), CYP1A2 and CYP2C8 (minor)
Elimination
Half-Life: 30.9 hr
Excretion: Feces (Primarily); urine (<4%)