Targretin Drug Information

TARGRETIN ® (bexarotene) Capsules are indicated for the treatment of cutaneous manifestations of cutaneous T-cell lymphoma in patients who are refractory to at least one prior systemic therapy.

The recommended initial dose of TARGRETIN is 300 mg/m 2 /day (see Table 1). TARGRETIN should be taken as a single oral daily dose with a meal. For precautions to prevent pregnancy and birth defects in women of child-bearing potential.

When toxicity is controlled, doses may be carefully readjusted upward. Duration of Therapy: In clinical trials in CTCL, TARGRETIN was administered for up to 97 weeks.

Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The safety of TARGRETIN has been evaluated in two clinical trials of 152 patients with CTCL who received TARGRETIN for up to 97 weeks and in 352 patients in other trials. The mean duration of therapy for the 152 patients with CTCL was 166 days.

The most common adverse events reported with an incidence of at least 10% in patients with CTCL treated at an initial dose of 300 mg/m 2 /day of TARGRETIN are shown in Table 2. The events at least possibly related to treatment are lipid abnormalities (elevated triglycerides, elevated total and LDL cholesterol and decreased HDL cholesterol), hypothyroidism, headache, asthenia, rash, leukopenia, anemia, nausea, infection, peripheral edema, abdominal pain, and dry skin. Most adverse events occurred at a greater incidence in patients treated at starting doses of greater than 300 mg/m 2 /day (see Table 2).

Adverse reactions leading to TARGRETIN dose reduction or discontinuation in at least two patients were hyperlipemia, neutropenia/leukopenia, diarrhea, fatigue/lethargy, hypothyroidism, headache, liver function test abnormalities, rash, pancreatitis, nausea, anemia, allergic reaction, muscle spasm, pneumonia, and confusion. The NCI Grade 3 and NCI Grade 4 adverse reactions reported in two or more patients with CTCL treated at an initial dose of 300 mg/m 2 /day of TARGRETIN (see Table 3) were hypertriglyceridemia, pruritus, headache, peripheral edema, leukopenia, rash, and hypercholesteremia. Most of these moderately severe or severe adverse events occurred at a higher rate in patients treated at starting doses of greater than 300 mg/m 2 /day than in patients treated at a starting dose of 300 mg/m 2 /day.

Other Grade 3 and 4 laboratory abnormalities are shown in Table 3. The common adverse reactions (incidence greater than 10%) were similar to those seen in patients with CTCL. In the 504 patients (CTCL and non-CTCL) who received TARGRETIN as monotherapy, drug-related serious adverse reactions that were fatal, in one patient each, were acute pancreatitis, subdural hematoma, and liver failure.

In the patients with CTCL receiving an initial dose of 300 mg/m 2 /day of TARGRETIN, adverse reactions reported at an incidence of less than 10% and not included in Tables 2 through 4 or discussed in other parts of labeling and possibly related to treatment were as follows: Body as a Whole: chills, cellulitis, chest pain, breast pain, sepsis, and monilia infection. Cardiovascular: hemorrhage, hypertension, angina pectoris, right heart failure, syncope, and tachycardia. Digestive: constipation, dry mouth, flatulence, colitis, dyspepsia, cheilitis, gastroenteritis, gingivitis, liver failure, and melena.

Hemic and Lymphatic: eosinophilia, thrombocythemia, coagulation time increased, lymphocytosis, and thrombocytopenia. Metabolic and Nutritional: LDH increased, creatinine increased, hypoproteinemia, hyperglycemia, weight decreased, weight increased, and amylase increased. Musculoskeletal: arthralgia, myalgia, bone pain, myasthenia, and arthrosis.

Nervous: depression, agitation, ataxia, cerebrovascular accident, confusion, dizziness, hyperesthesia, hypesthesia, and neuropathy. Respiratory: pharyngitis, rhinitis, dyspnea, pleural effusion, bronchitis, cough increased, lung edema, hemoptysis, and hypoxia. Skin and Appendages: skin ulcer, acne, alopecia, skin nodule, macular papular rash, pustular rash, serous drainage, and vesicular bullous rash.

Special Senses: dry eyes, conjunctivitis, ear pain, blepharitis, corneal lesion, keratitis, otitis externa, and visual field defect. Urogenital: albuminuria, hematuria, urinary incontinence, urinary tract infection, urinary urgency, dysuria, and kidney function abnormal. Table 2: Adverse Events with Incidence ≥10% in CTCL Trials Adverse Events Reported in at Least Two Patients (CTCL Trials) Table 4: Treatment-Emergent Abnormal Laboratory Values in CTCL Trials The safety profile from the one post-approval trial with 59 subjects was generally comparable to that of the pivotal trials with the exception of serious adverse events hypertriglyceridemia, neutropenia and bone marrow failure which were observed more frequently in the TARGRETIN 300 mg/m 2 /day group than in the TARGRETIN 150 mg/m 2 /day group.

Severe hypertriglyceridemia (≥800 mg/dL) was not seen in any subject in the lower dosage arm.

Effect of Other Drugs on TARGRETIN Gemfibrozil: Concomitant administration of TARGRETIN and gemfibrozil resulted in increases in plasma concentrations of bexarotene. Concomitant administration of gemfibrozil with TARGRETIN is not recommended. Effect of TARGRETIN on Other Drugs TARGRETIN may be an inducer for the CYP3A4 enzymes, and may reduce plasma concentrations of other substrates metabolized by CYP3A4.

Drug products which may be affected include oral or other systemic hormonal contraceptives. Thus, if treatment with TARGRETIN is intended for a female with reproductive potential, it is strongly recommended that a non-hormonal contraception be considered. Laboratory Test Interference CA125 assay values in patients with ovarian cancer may be increased by TARGRETIN therapy.

Pregnancy Risk Summary TARGRETIN, a retinoid, can cause fetal harm based on findings from animal studies when administered to a pregnant female and is contraindicated during pregnancy. Bexarotene was teratogenic and caused developmental mortality in rats following oral administration during organogenesis. TARGRETIN must not be given to a pregnant female or a female who intends to become pregnant.

If pregnancy does occur during treatment with TARGRETIN, immediately discontinue the drug and advise the pregnant female of the potential risk to a fetus. The background risk of major birth defects and miscarriage for the indicated populations is unknown. However, the background risk in the U.S. general population of major birth defects is 2-4% and of miscarriage is 15-20% of clinically recognized pregnancies.

Data Animal Data Bexarotene caused malformations when administered orally to pregnant rats during days 7-17 of gestation. Developmental abnormalities included incomplete ossification at 4 mg/kg/day and cleft palate, depressed eye bulge/microphthalmia, and small ears at 16 mg/kg/day. The plasma AUC of bexarotene in rats at 4 mg/kg/day is approximately one third the AUC in humans at the recommended daily dose.

At doses greater than 10 mg/kg/day, bexarotene caused developmental mortality. The no effect dose for fetal effects in rats was 1 mg/kg/day (producing an AUC approximately one sixth of the AUC at the recommended human daily dose).

Pediatric Use Safety and effectiveness of TARGRETIN in pediatric patients have not been established.

Pregnancy TARGRETIN can cause fetal harm when administered to a pregnant female. TARGRETIN is a member of the retinoid class of drugs that is associated with birth defects in humans and is contraindicated in females who are pregnant. Bexarotene was also teratogenic and caused developmental mortality when administered orally to pregnant rats.

If this drug is used during pregnancy or if the patient becomes pregnant while taking this drug, the patient should be advised of the potential risk to a fetus.

Hypersensitivity TARGRETIN Capsules are contraindicated in patients with a known serious hypersensitivity to bexarotene or other components of the product.

Doses up to 1000 mg/m 2 /day of TARGRETIN have been administered in short-term trials in patients with advanced cancer without acute toxic effects. Single doses of 1500 mg/kg and 720 mg/kg were tolerated without significant toxicity in rats and dogs, respectively. These doses are approximately 30 and 50 times, respectively, the recommended human dose on a mg/m 2 basis.