Tretinoin Drug Information

Tretinoin capsules are indicated for the induction of remission in adults and pediatric patients 1 year of age and older with acute promyelocytic leukemia (APL) characterized by the presence of the t(15;17) translocation or PML/RARα gene expression, and who are refractory to or who have relapsed from anthracycline chemotherapy or for whom anthracycline-based chemotherapy is contraindicated.

Important Safety Information

Verify pregnancy status in females of reproductive potential prior to initiating tretinoin capsules. Females of reproductive potential must have a negative pregnancy test before initiating tretinoin capsules.

Recommended Dosage

The recommended dosage of tretinoin capsules is 22.5 mg/m 2 orally twice daily until complete remission is documented. Discontinue tretinoin capsules 30 days after achievement of complete remission or after 90 days of treatment, whichever occurs first. Discontinue tretinoin capsules if the t(15;17) translocation or PML/RARα fusion has not been identified.

Take tretinoin capsules with a meal. Swallow tretinoin capsules whole with water. Do not chew, dissolve, or open capsule.

Do not take a missed dose of tretinoin capsules unless it is more than 10 hours until the next scheduled dose. If vomiting occurs after tretinoin capsules administration, do not take an additional dose, but continue with the next scheduled dose.

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. Acute Promyelocytic Leukemia The safety of tretinoin capsules was evaluated in patients with APL who received tretinoin capsules at a dose of 22.5 mg/m 2 orally twice daily. The most common adverse reactions (≥30%) were headache, fever, skin/mucous membrane dryness, bone pain, malaise, shivering, upper respiratory tract disorders, dyspnea, hemorrhage, infections, nausea/vomiting, rash, peripheral edema, leukocytosis, pain, gastrointestinal hemorrhage, chest discomfort, abdominal pain.

Table 1 summarizes the adverse reactions for patients with APL. Table 1. Adverse Reactions (≥ 10%) Occurring in Patients with APL Who Received 1 Differentiation syndrome can be associated with other commonly reported events such as fever, leukocytosis, dyspnea, pneumonia, pleural effusion, pericardial effusion, hypotension, edema, weight gain, and renal failure.

Adverse reactions that occurred in <10% of patients who received tretinoin capsules include: • Hepatobiliary disorders: Hepatosplenomegaly (9%), hepatitis (3%), unspecified liver disorder (3%). • Musculoskeletal and connective tissue disorders: Flank pain (9%), bone inflammation (3%). • Nervous system disorders: Agitation (9%), cerebral hemorrhage (9%), intracranial hypertension (9%), hallucination (6%), abnormal gait, agnosia, aphasia, asterixis, cerebellar edema, cerebellar disorders, convulsions, coma, CNS depression, dysarthria, encephalopathy, facial paralysis, hemiplegia, hyporeflexia, hypotaxia, no light reflex, neurologic reaction, spinal cord disorder, stroke, tremor, leg weakness, unconsciousness, dementia, forgetfulness, somnolence, and slow speech (3% each). • Renal and urinary disorders: Dysuria (9%), acute renal failure, micturition frequency, renal tubular necrosis, and enlarged prostate (3% each). • Respiratory, thoracic and mediastinal disorders: Lower respiratory tract disorders (9%), pulmonary infiltration (6%), bronchial asthma, pulmonary edema, larynx edema, and unspecified pulmonary disease (3% each). • Infections and infestations: Cellulitis (8%). • Blood and lymphatic system disorders: Lymph disorders (6%). • Cardiovascular disorders: Cardiac failure (6%), cardiac arrest, myocardial infarction, enlarged heart, heart murmur, myocarditis, pericarditis, and secondary cardiomyopathy (3% each). • Ear and labyrinth disorders: Hearing loss and other unspecified auricular disorders (6%), irreversible hearing loss (<1%). • General disorders: Face edema (6%), pallor (6%), hypothermia (3%). • Metabolism and nutrition disorders: Fluid imbalance (6%), acidosis (3%). • Eye disorders: Changed visual acuity (6%), visual field defects (3%). • Gastrointestinal disorders: Ascites, ulcer (3% each). • Vascular disorders: Ischemia and pulmonary hypertension (3% each).

Postmarketing Experience

Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Erythema nodosum, basophilia and hyperhistaminemia, Sweet’s Syndrome, organomegaly, hypercalcemia, pancreatitis, myositis, thrombosis (both venous and arterial), thrombocytosis, genital ulceration and vasculitis, predominantly involving the skin.

Effects of Other Drugs on Tretinoin Capsules Strong or moderate CYP3A Inhibitors Avoid concomitant use of tretinoin capsules with strong CYP3A inhibitors if possible and monitor more frequently if concomitant use is unavoidable. Monitor patients taking moderate CYP3A inhibitors concomitantly with tretinoin capsules more frequently for adverse reactions. Tretinoin is a CYP3A substrate.

Concomitant use with a strong CYP3A4 inhibitor increases tretinoin plasma concentrations, which may increase the risk of adverse reactions. Strong CYP3A Inducers Concomitant use of tretinoin capsules with strong CYP3A4 inducers may decrease tretinoin plasma concentrations, which may reduce its efficacy. Avoid concomitant use with strong CYP3A inducers if possible.

Concomitant Use of Products Known to Cause Intracranial Hypertension Intracranial hypertension has been reported in patients who received tretinoin capsules and concomitant use of other products that can cause intracranial hypertension, such as tetracyclines, may increase the risk. Avoid concomitant use of tretinoin capsules with other products agents that can cause intracranial hypertension.

Vitamin A The concomitant use of vitamin A with tretinoin capsules may lead to vitamin A related adverse reactions. Avoid concomitant use of tretinoin capsules with vitamin A.

Anti-fibrinolytic Agents

Fatal thrombotic complications have been reported in patients who have received tretinoin capsules and concomitant use of anti-fibrinolytic agents may increase the risk. Avoid concomitant use of tretinoin capsules with anti-fibrinolytic agents.

Pregnancy Risk Summary Based on findings in animals and its mechanism of action, tretinoin capsules can cause embryo-fetal loss and malformations when administered to a pregnant woman. Tretinoin capsules are a retinoid and there is an increased risk of major congenital malformations, spontaneous abortions and premature births following exposure to retinoids during pregnancy in humans. Tretinoin was teratogenic and embryotoxic in mice, rats, hamsters, rabbits and pigtail monkeys at doses less than the human dose on a mg/m 2 basis (see Data).

Advise pregnant women of the potential risk to a fetus. The estimated background risk of major birth defects and miscarriage for the indicated population(s) is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes.

In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is respectively. Data Human Data Tretinoin capsules are a retinoid and increased spontaneous abortions and major fetal abnormalities related to the use of retinoids have been documented in humans. Reported malformations include abnormalities of the central nervous system, musculoskeletal system, external ear, eye, thymus and great vessels; and facial dysmorphia, cleft palate, and parathyroid hormone deficiency.

Some of these abnormalities were fatal. IQ scores less than 85, with or without obvious CNS abnormalities, have been reported in pediatrics exposed to retinoids in utero. Animal Data Tretinoin causes fetal resorptions and a decrease in live fetuses in all animals studied.

Gross external, soft tissue and skeletal alterations occurred at doses higher than 0.7 mg/kg/day in mice, 2 mg/kg/day in rats, 7 mg/kg/day in hamsters, and at a dose of 10 mg/kg/day, the only dose tested, in pigtail monkeys (about times the human dose, respectively, on a mg/m 2 basis).

Pediatric Use Safety and effectiveness of tretinoin capsules have been established in pediatric patients 1 year of age and older and the information on this use is discussed throughout the labeling. The maximum tolerated dose is lower in pediatric patients compared to adults. Some pediatric patients experience severe headache and intracranial hypertension, which required management with an analgesic and a lumbar puncture.

Dose reduction may be considered for pediatric patients experiencing serious and/or intolerable adverse reactions. Safety and effectiveness in pediatric patients less than 1 year of age have not been established.

Tretinoin capsules are contraindicated in patients with a known hypersensitivity to tretinoin capsules, any of its components, or other retinoids. Reactions have included rash, pruritus, face edema, and dyspnea.

In case of overdose with tretinoin capsules, reversible signs of hypervitaminosis A (headache, nausea, vomiting, mucocutaneous symptoms) can appear. Overdosage with other retinoids has been associated with transient headache, facial flushing, cheilosis, abdominal pain, dizziness and ataxia. These symptoms have quickly resolved without apparent residual effects.

There is no specific treatment in the case of an overdose; however, it is important that the patient be treated in a special hematological unit.