DEFLAZACORT Drug Interactions: What You Need to Know

INTERACTIONS Moderate or strong CYP3A4 inhibitors: Give one third of the recommended dosage of PYQUVI ( 7.1 ) Avoid use of moderate or strong CYP3A4 inducers with PYQUVI, as they may reduce efficacy ( 7.1 )

See

17 for PATIENT COUNSELING INFORMATION and FDA-approved patient labeling. Additional pediatric use information is approved for PTC Therapeutics, Inc.'s Emflaza ® (deflazacort) oral suspension. However, due to PTC Therapeutics, Inc.'s marketing exclusivity rights, this drug product is not labeled with that information.

7.1 CYP3A4 Inhibitors and Inducers Moderate or Strong CYP3A4 Inhibitors The active metabolite of deflazacort, 21-desDFZ, is a substrate of CYP3A4 <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 )]</span> . Co-administration of deflazacort with clarithromycin, a strong CYP3A4 inhibitor, increased total exposure to 21-desDFZ by about 3-fold. Therefore, give one third the recommended dosage of PYQUVI when moderate or strong CYP3A4 inhibitors (e.g., clarithromycin, fluconazole, diltiazem, verapamil, grapefruit juice) are used concomitantly with PYQUVI <span class="opacity-50 text-xs">[see Dosage and Administration ( 2.5 ) and Clinical Pharmacology ( 12.3 )]</span> . Moderate or Strong CYP3A4 Inducers Co-administration of deflazacort with rifampin, a strong CYP3A4 inducer, significantly decreased the exposure of 21-desDFZ. Avoid concomitant use of strong (e.g., efavirenz) or moderate (e.g., carbamazepine, phenytoin) CYP3A4 inducers with PYQUVI <span class="opacity-50 text-xs">[see Dosage and Administration ( 2.5 ) and Clinical Pharmacology ( 12.3 )]</span> .

7.2 Neuromuscular Blockers Patients receiving corticosteroids, including PYQUVI, and concomitant therapy with neuromuscular blocking drugs (e.g., pancuronium) may be at increased risk of developing an acute myopathy <span class="opacity-50 text-xs">[see Warnings and Precautions ( 5.11 )]</span> .

Deflazacort oral suspension is contraindicated in patients with known hypersensitivity to deflazacort or to any of the inactive ingredients. Instances of hypersensitivity, including anaphylaxis, have occurred in patients receiving corticosteroid therapy [see Warnings and Precautions ( 5.15 ) and Adverse Reactions ( 6.2 )] . Hypersensitivity to deflazacort or any of the inactive ingredients in deflazacort oral suspension ( 4 )

AND PRECAUTIONS Alterations in Endocrine Function: Hypothalamic-pituitary-adrenal axis suppression, Cushing’s syndrome, and hyperglycemia can occur; Monitor patients for these conditions with chronic use of deflazacort oral suspension ( 2.3 , 5.1 ) Immunosuppression and Increased Risk of Infection: Increased risk of new, exacerbation, dissemination, or reactivation of latent infections, which can be severe and at times fatal; Signs and symptoms of infection may be masked ( 5.2 ) Alterations in Cardiovascular/Renal Function: Monitor for elevated blood pressure and sodium, and for decreased potassium levels ( 5.3 )

Gastrointestinal

Perforation: Increased risk in patients with certain GI disorders; Signs and symptoms may be masked ( 5.4 ) Behavioral and Mood Disturbances: May include euphoria, insomnia, mood swings, personality changes, severe depression, and psychosis ( 5.5 ) Effects on Bones: Monitor for decreases in bone mineral density with chronic use of deflazacort oral suspension ( 5.6 )

Ophthalmic

Effects: May include cataracts, infections, and glaucoma; Monitor intraocular pressure if deflazacort oral suspension is continued for more than 6 weeks ( 5.7 ) Vaccination: Do not administer live or live attenuated vaccines to patients receiving immunosuppressive doses of corticosteroids. Administer live-attenuated or live vaccines at least 4 to 6 weeks prior to starting deflazacort oral suspension ( 5.8 )

Serious Skin

Rashes: Discontinue at the first sign of rash, unless the rash is clearly not drug related ( 5.9 )

5.1 Alterations in Endocrine Function Corticosteroids, such as deflazacort oral suspension, can cause serious and life-threatening alterations in endocrine function, especially with chronic use. Monitor patients receiving deflazacort oral suspension for Cushing’s syndrome, hyperglycemia, and adrenal insufficiency after deflazacort oral suspension withdrawal. In addition, patients with hypopituitarism, primary adrenal insufficiency or congenital adrenal hyperplasia, altered thyroid function, or pheochromocytoma may be at increased risk for adverse endocrine events. Risk of Adrenal Insufficiency Following Corticosteroid Withdrawal Corticosteroids produce reversible hypothalamic-pituitary-adrenal (HPA) axis suppression, with the potential for the development of secondary adrenal insufficiency after withdrawal of corticosteroid treatment. Acute adrenal insufficiency can occur if corticosteroids are withdrawn abruptly, and can be fatal. The degree and duration of adrenocortical insufficiency produced is variable among patients and depends on the dose, frequency, and duration of corticosteroid therapy. The risk is reduced by gradually tapering the corticosteroid dose when withdrawing treatment. This insufficiency may persist, however, for months after discontinuation of prolonged therapy; therefore, in any situation of stress occurring during that period of discontinuation, corticosteroid therapy should be reinstituted. For patients already taking corticosteroids during times of stress, the dosage may need to be increased. A steroid “withdrawal syndrome”, seemingly unrelated to adrenocortical insufficiency, may also occur following abrupt discontinuance of corticosteroids. This syndrome includes symptoms such as anorexia, nausea, vomiting, lethargy, headache, fever, joint pain, desquamation, myalgia, and/or weight loss. These effects are thought to be due to the sudden change in corticosteroid concentration rather than to low corticosteroid levels. Cushing’s Syndrome Cushing’s syndrome (hypercortisolism) occurs with prolonged exposure to exogenous corticosteroids, including deflazacort oral suspension. Symptoms include hypertension, truncal obesity and thinning of the limbs, purple striae, facial rounding, facial plethora, muscle weakness, easy and frequent bruising with thin fragile skin, posterior neck fat deposition, osteopenia, acne, amenorrhea, hirsutism and psychiatric abnormalities.

Hyperglycemia

Corticosteroids can increase blood glucose, worsen pre-existing diabetes, predispose those on long-term therapy to diabetes mellitus, and may reduce the effect of anti-diabetic drugs. Monitor blood glucose at regular intervals. For patients with hyperglycemia, anti-diabetic treatment should be initiated or adjusted accordingly. Considerations for Use in Patients with Altered Thyroid Function Metabolic clearance of corticosteroids is decreased in hypothyroid patients and increased in hyperthyroid patients. Changes in thyroid status of the patient may necessitate a dose adjustment of the corticosteroid. When concomitant administration of corticosteroids and levothyroxine is required, administration of corticosteroid should precede the initiation of levothyroxine therapy to reduce the risk of adrenal crisis.

Pheochromocytoma Crisis

There have been reports of pheochromocytoma crisis, which can be fatal, after administration of systemic corticosteroids. In patients with suspected or identified pheochromocytoma, consider the risk of pheochromocytoma crisis prior to administering corticosteroids.

5.2 Immunosuppression and Increased Risk of Infection Corticosteroids, including deflazacort oral suspension, suppress the immune system and increase the risk of infection with any pathogen, including viral, bacterial, fungal, protozoan, or helminthic pathogens. Corticosteroids can:

• Reduce resistance to new infections
• Exacerbate existing infections
• Increase the risk of disseminated infections
• Increase the risk of reactivation or exacerbation of latent infections
• Mask some signs of infections Corticosteroid-associated infections can be mild but can be severe, and at times fatal. The rate of infectious complications increases with increasing corticosteroid dosages. Monitor for the development of infection and consider deflazacort oral suspension withdrawal or dosage reduction as needed. Tuberculosis If deflazacort oral suspension is used to treat a condition in patients with latent tuberculosis or tuberculin reactivity, reactivation of tuberculosis may occur. Closely monitor such patients for reactivation. During prolonged deflazacort oral suspension therapy, patients with latent tuberculosis or tuberculin reactivity should receive chemoprophylaxis.

Varicella

Zoster and Measles Viral Infections Varicella and measles can have a serious or even fatal course in non-immune patients taking corticosteroids, including deflazacort oral suspension. In corticosteroid-treated patients who have not had these diseases or are non-immune, particular care should be taken to avoid exposure to varicella and measles. If a deflazacort-treated patient is exposed to varicella, prophylaxis with varicella zoster immunoglobulin may be indicated. If varicella develops, treatment with antiviral agents may be considered. If a deflazacort-treated patient is exposed to measles, prophylaxis with immunoglobulin may be indicated. Hepatitis B Virus Reactivation Hepatitis B virus reactivation can occur in patients who are hepatitis B carriers treated with immunosuppressive dosages of corticosteroids, including deflazacort oral suspension. Reactivation can also occur infrequently in corticosteroid-treated patients who appear to have resolved hepatitis B infection. Screen patients for hepatitis B infection before initiating immunosuppressive (e.g., prolonged) treatment with deflazacort oral suspension. For patients who show evidence of hepatitis B infection, recommend consultation with physicians with expertise in managing hepatitis B regarding monitoring and consideration for hepatitis B antiviral therapy.

Fungal Infections

Corticosteroids, including deflazacort oral suspension, may exacerbate systemic fungal infections; therefore, avoid deflazacort oral suspension use in the presence of such infections unless deflazacort oral suspension is needed to control drug reactions. For patients on chronic deflazacort oral suspension therapy who develop systemic fungal infections, deflazacort oral suspension withdrawal or dose reduction is recommended.

Amebiasis

Corticosteroids, including deflazacort oral suspension, may activate latent amebiasis. Therefore, it is recommended that latent amebiasis or active amebiasis be ruled out before initiating deflazacort oral suspension in patients who have spent time in the tropics or patients with unexplained diarrhea.

Strongyloides Infestation

Corticosteroids, including deflazacort oral suspension, should be used with great care in patients with known or suspected Strongyloides (threadworm) infestation. In such patients, corticosteroid-induced immunosuppression may lead to Strongyloides hyperinfection and dissemination with widespread larval migration, often accompanied by severe enterocolitis and potentially fatal gram-negative septicemia.

Cerebral Malaria

Avoid corticosteroids, including deflazacort oral suspension, in patients with cerebral malaria.

5.3 Alterations in Cardiovascular/Renal Function Corticosteroids, including deflazacort oral suspension, can cause elevation of blood pressure, salt, and water retention, and increased excretion of potassium and calcium. Monitor blood pressure and assess for signs and symptoms of volume overload. Monitor serum potassium levels. Dietary salt restriction and potassium supplementation may be necessary. Deflazacort oral suspension should be used with caution in patients with congestive heart failure, hypertension, or renal insufficiency. Literature reports suggest an association between use of corticosteroids and left ventricular free wall rupture after a recent myocardial infarction; therefore, therapy with deflazacort oral suspension should be used with great caution in these patients.

5.4 Gastrointestinal Perforation There is an increased risk of gastrointestinal perforation during corticosteroid use in patients with certain gastrointestinal disorders such as active or latent peptic ulcers, diverticulitis, fresh intestinal anastomoses, and non-specific ulcerative colitis. Signs of gastrointestinal perforation, such as peritoneal irritation, may be masked in patients receiving corticosteroids. Avoid corticosteroids if there is a probability of impending perforation, abscess, or other pyogenic infections; diverticulitis; fresh intestinal anastomoses; or active or latent peptic ulcer.

5.5 Behavioral and Mood Disturbances Potentially severe psychiatric adverse reactions may occur with systemic corticosteroids, including deflazacort oral suspension. Symptoms typically emerge within a few days or weeks of starting treatment and may be dose-related. These reactions may improve after either dose reduction or withdrawal, although pharmacologic treatment may be necessary. Psychiatric adverse reactions usually involve hypomanic or manic symptoms (e.g., euphoria, insomnia, mood swings) during treatment and depressive episodes after discontinuation of treatment. Inform patients or caregivers of the potential for behavioral and mood changes and encourage them to seek medical attention if psychiatric symptoms develop, especially if depressed mood or suicidal ideation is suspected.

5.6 Effects on Bones Decreased Bone Mineral Density Corticosteroids, including deflazacort oral suspension, decrease bone formation and increase bone resorption both through their effect on calcium regulation (i.e., decreasing absorption and increasing excretion) and inhibition of osteoblast function. This, together with a decrease in the protein matrix of the bone secondary to an increase in protein catabolism and reduced sex hormone production, may lead to inhibition of bone growth in pediatric patients and the development of bone loss at any age. Bone loss can predispose patients to vertebral and long bone fractures. Consider a patient’s risk of osteoporosis before initiating corticosteroid therapy. Monitor bone mineral density in patients on long-term treatment with deflazacort oral suspension.

Avascular Necrosis

Corticosteroids, including deflazacort oral suspension, may cause avascular necrosis.

5.7 Ophthalmic Effects Use of corticosteroids, including deflazacort oral suspension, may produce posterior subcapsular cataracts. Corticosteroids may also cause glaucoma with possible damage to the optic nerves, and may increase the risk of secondary ocular infections caused by bacteria, fungi, or viruses. Corticosteroids are not recommended for patients with active ocular herpes simplex. Intraocular pressure may become elevated in some patients taking corticosteroids. If treatment with deflazacort oral suspension is continued for more than 6 weeks, monitor intraocular pressure.

5.8 Immunizations Administer all immunizations according to immunization guidelines prior to starting deflazacort oral suspension. Administer live-attenuated or live vaccines at least 4 to 6 weeks prior to starting deflazacort oral suspension. Patients on deflazacort oral suspension may receive concurrent vaccinations, except for live-attenuated or live vaccines.

5.9 Serious Skin Rashes Toxic epidermal necrolysis has been reported with the use of deflazacort with symptoms beginning within 8 weeks of starting treatment. Discontinue at the first sign of rash, unless the rash is clearly not drug related.

5.10 Effects on Growth and Development Long-term use of corticosteroids, including deflazacort oral suspension, can have negative effects on growth and development in children.

5.11 Myopathy Patients receiving corticosteroids, including deflazacort oral suspension, and concomitant therapy with neuromuscular blocking agents (e.g., pancuronium) or patients with disorders of neuromuscular transmission (e.g., myasthenia gravis) may be at increased risk of developing acute myopathy. This acute myopathy is generalized, may involve ocular and respiratory muscles, and may result in quadriparesis. Elevation of creatine kinase may occur. Clinical improvement or recovery after stopping corticosteroids may require weeks to years.

5.12 Kaposi’s Sarcoma Kaposi’s sarcoma has been reported to occur in patients receiving corticosteroid therapy, most often for chronic conditions. Discontinuation of corticosteroids may result in clinical improvement of Kaposi’s sarcoma.

5.13 Risk of Serious Adverse Reactions in Infants because of Benzyl Alcohol Preservative Deflazacort oral suspension contains benzyl alcohol and is not approved for use in pediatric patients less than 2 years of age. Serious and fatal adverse reactions including “gasping syndrome” can occur in neonates and low birth weight infants treated with benzyl alcohol-preserved drugs, including deflazacort oral suspension. The “gasping syndrome” is characterized by central nervous system depression, metabolic acidosis, and gasping respirations. When prescribing deflazacort oral suspension, consider the combined daily metabolic load of benzyl alcohol from all sources, including deflazacort oral suspension (Deflazacort oral suspension contains 10.45 mg of benzyl alcohol per mL) and other drugs containing benzyl alcohol. The minimum amount of benzyl alcohol at which serious adverse reactions may occur is not known. At the recommended dose of 0.9 mg/kg/day of deflazacort oral suspension, patients would receive approximately 0.4 mg/kg/day of benzyl alcohol <span class="opacity-50 text-xs">[see Use in Specific Populations ( 8.4 )]</span> .

5.14 Thromboembolic Events Observational studies have shown an increased risk of thromboembolism (including venous thromboembolism) particularly with higher cumulative doses of corticosteroids. It is unclear if risk differs by daily dose or duration of use. Use deflazacort oral suspension with caution in patients who have or may be predisposed to thromboembolic disorders.

5.15 Anaphylaxis Rare instances of anaphylaxis have occurred in patients receiving corticosteroid therapy, including deflazacort oral suspension.