Doxercalciferol

1 INDICATIONS AND USAGE • Doxercalciferol Injection is indicated for the treatment of secondary hyperparathyroidism in adult patients with CKD on dialysis. Doxercalciferol is a synthetic vitamin D 2 analog: • Doxercalciferol Injection is indicated for the treatment of secondary hyperparathyroidism in adult patients with CKD on dialysis.

2 DOSAGE AND ADMINISTRATION Before initiating treatment, ensure serum calcium is not above the upper limit of normal. ( 2.1 ) • Dosage for Doxercalciferol Injection in patients with CKD on dialysis: Initiate dosing at 4 mcg by bolus intravenous administration three times weekly at the end of dialysis (no more frequently than every other day). Maximum dose is 18 mcg weekly. (2.4) • Target the maintenance dose of Doxercalciferol Injection to intact parathyroid hormone (PTH) levels within the desired therapeutic range and serum calcium within normal limits.( 2 ) • See Full Prescribing Information for dose titration, laboratory monitoring, and important administration instructions. 2.1 Prior to Initiation of Doxercalciferol Injection • Ensure serum calcium is not above the upper limit of normal before initiating treatment with Doxercalciferol Injection [see Warnings and Precautions (5.1)]. 2.4 Important Administration Instructions for Doxercalciferol Injection • Administer Doxercalciferol Injection intravenously as a bolus dose at the end of dialysis. • Inspect Doxercalciferol Injection visually prior to administration; the solution should appear clear and colorless. Do not use if the solution is not clear or particles are present. • After initial vial use: o discard unused portion of the single-dose vial; o store opened multiple-dose vial for up to 3 days at 2°C to 8°C (36°F to 46°F). Discard unused portion of multiple-dose vial after 3 days [see How Supplied/Storage and Handling (16)]. 2.5 Dosage Recommendations for Doxercalciferol Injection in Patients with CKD on Dialysis • Initiate Doxercalciferol Injection at a dose of 4 mcg given by bolus intravenous administration three times weekly at the end of dialysis (no more frequently than every other day). • Target the maintenance dose of Doxercalciferol Injection to intact parathyroid hormone (PTH) levels within the desired therapeutic range and serum calcium within normal limits. • Monitor serum calcium, phosphorus, and intact PTH levels weekly after initiation of therapy or dose adjustment. • Titrate the dose of Doxercalciferol Injection based on intact PTH. The dose may be increased at 8-week intervals by 1 mcg to 2 mcg if intact PTH is not lowered by 50% and fails to reach the target range. The maximum dose is 18 mcg weekly. Prior to raising the dose, ensure serum calcium is within normal limits. • Suspend or decrease the dose if intact PTH is persistently and abnormally low to reduce the risk of adynamic bone disease [see Warnings and Precautions (5.4)] or if serum calcium is consistently above the normal range to reduce the risk of hypercalcemia [see Warnings and Precautions (5.1)] . If suspended, the drug should be restarted one week later at a dose that is at least 1 mcg lower. 2.6 Drug Interactions that May Require Dosage Adjustments of Doxercalciferol Injection • Increased monitoring of serum calcium and dose adjustment of Doxercalciferol Injection may be necessary when given concomitantly with drugs that may increase the risk of hypercalcemia [see Drug Interactions (7)]. • Increased monitoring of both serum calcium and intact PTH as well as dose adjustment of Doxercalciferol Injection may be necessary when given concomitantly with cytochrome P450 inhibitors or enzyme inducers [see Drug Interactions (7)].

4 CONTRAINDICATIONS Doxercalciferol Injection is contraindicated in patients with: • Hypercalcemia [see Warnings and Precautions (5.1) ] • Vitamin D toxicity [see Warnings and Precautions (5.1) ] • Known hypersensitivity to doxercalciferol or any of the inactive ingredients of Doxercalciferol Injection; serious hypersensitivity reactions including anaphylaxis and angioedema have been reported [see Warnings and Precautions (5.3), Adverse Reactions (6.2)]. • Hypercalcemia( 4 ) • Vitamin D toxicity( 4 ) • Know hypersensitivity to doxercalciferol or any of the inactive ingredients of Doxercalciferol Injection

5 WARNINGS AND PRECAUTIONS • Hypercalcemia: Can occur during treatment with Doxercalciferol Injection and can lead to cardiac arrhythmias and seizures. Severe hypercalcemia may require emergency attention. Risk may be increased when used concomitantly with high dose calcium preparations, thiazide diuretics, or vitamin D compounds. Monitor serum calcium prior to initiation and during treatment and adjust dose accordingly.(2, 5.1) • Digitalis Toxicity: Hypercalcemia increases the risk of digitalis toxicity. In patients using digitalis compounds, monitor serum calcium and patients for signs and symptoms of digitalis toxicity. Increase frequency of monitoring when initiating or adjusting the dose of Doxercalciferol Injection.(5.2) • Serious Hypersensitivity Reactions: Anaphylaxis, with symptoms of angioedema, hypotension, unresponsiveness, chest discomfort, shortness of breath, and cardiopulmonary arrest, has been reported in hemodialysis patients after administration of Doxercalciferol Injection. Monitor patients upon treatment initiation for hypersensitivity reactions. Should a reaction occur, discontinue and treat.(5.3) • Adynamic Bone Disease: May develop and increase risk of fractures if intact PTH levels are suppressed to abnormally low levels. Monitor intact PTH levels to avoid oversuppression and adjust dose if needed.(5.4) 5.1 Hypercalcemia Hypercalcemia may occur during Doxercalciferol Injection treatment. Acute hypercalcemia may increase the risk of cardiac arrhythmias and seizures and may potentiate the effect of digitalis on the heart [see Warnings and Precautions (5.2)]. Chronic hypercalcemia can lead to generalized vascular calcification and other soft-tissue calcification. Severe hypercalcemia may require emergency attention. Hypercalcemia may be exacerbated by concomitant administration of high doses of calcium-containing preparations, thiazide diuretics, or other vitamin D compounds [see Drug Interactions (7)] . In addition, high intake of calcium and phosphate concomitantly with vitamin D compounds may lead to hypercalciuria and hyperphosphatemia. Patients with a history of hypercalcemia prior to initiating therapy may be at increased risk for development of hypercalcemia with Doxercalciferol Injection. In these circumstances, frequent serum calcium monitoring and Doxercalciferol Injection dose adjustments may be required. When initiating Doxercalciferol Injection or adjusting Doxercalciferol Injection dose, measure serum calcium frequently (weekly in patients with CKD on dialysis or every 2 weeks for patients with stage 3 or 4 CKD). Once a maintenance dose has been established, measure serum calcium monthly for 3 months and then every 3 months. If hypercalcemia occurs, reduce the dose or discontinue Doxercalciferol Injection until serum calcium is normal [see Dosage and Administration (2)]. Inform patients about the symptoms of elevated calcium (feeling tired, difficulty thinking clearly, loss of appetite, nausea, vomiting, constipation, increased thirst, increased urination and weight loss) and instruct them to report new or worsening symptoms when they occur. 5.2 Digitalis Toxicity Doxercalciferol Injection can cause hypercalcemia [see Warnings and Precautions (5.1)] which increases the risk of digitalis toxicity. In patients using Doxercalciferol Injection concomitantly with digitalis compounds, monitor both serum calcium and patients for signs and symptoms of digitalis toxicity. Increase the frequency of monitoring when initiating or adjusting the dose of Doxercalciferol Injection [see Drug Interactions (7)]. 5.3 Serious Hypersensitivity Reactions Serious hypersensitivity reactions, including fatal outcome, have been reported post marketing in patients on hemodialysis following administration of Doxercalciferol Injection. Hypersensitivity reactions include anaphylaxis with symptoms of angioedema (involving face, lips, tongue and airways), hypotension, unresponsiveness, chest discomfort, shortness of breath, and cardiopulmonary arrest. These reactions may occur separately or together. Monitor patients receiving Doxercalciferol Injection upon initiation of treatment for hypersensitivity reactions. Should a hypersensitivity reaction occur, discontinue Doxercalciferol Injection, monitor and treat if indicated [see Contraindications (4)]. 5.4 Adynamic Bone Disease Adynamic bone disease with subsequent increased risk of fractures may develop if intact PTH levels are suppressed by Doxercalciferol Injection to abnormally low levels. Monitor intact PTH levels to avoid oversuppression and adjust the Doxercalciferol Injection dose, if needed [see Dosage and Administration (2)].

7 DRUG INTERACTIONS Tables 2 include clinically significant drug interactions with Doxercalciferol Injection. Table 2: Clinically Significant Drug Interactions with Doxercalciferol Injection Drugs that May Increase the Risk of Hypercalcemia Clinical Impact Concomitant administration of high doses of calcium-containing preparations or other vitamin D compounds may increase the risk of hypercalcemia. Thiazide diuretics are known to induce hypercalcemia by reducing excretion of calcium in the urine. Examples Calcium-containing products, other vitamin D compounds or thiazide diuretics Intervention Monitor serum calcium concentrations more frequently and adjust Doxercalciferol Injection dose as needed [see Warnings and Precautions (5.1)]. Digitalis Compounds Clinical Impact Doxercalciferol can cause hypercalcemia which can potentiate the risk of digitalis toxicity. Intervention Monitor patients for signs and symptoms of digitalis toxicity and increase frequency of serum calcium monitoring when initiating or adjusting the dose of Doxercalciferol Injection in patients receiving digitalis compounds [see Warnings and Precautions (5.2)]. Cytochrome P450 Inhibitors Clinical Impact Doxercalciferol is activated by CYP 27 in the liver. Cytochrome P450 inhibitors may inhibit the 25-hydroxylation of doxercalciferol and thus reduce the formation of active doxercalciferol moiety [see Clinical Pharmacology (12.3)]. Examples Ketoconazole and erythromycin Intervention If a patient initiates or discontinues therapy with a cytochrome P450 inhibitor, dose adjustment of Doxercalciferol Injection may be necessary. Monitor intact PTH and serum calcium concentrations closely. Enzyme Inducers Clinical Impact Doxercalciferol is activated by CYP 27 in the liver. Enzyme inducers may affect the 25-hydroxylation of doxercalciferol [see Clinical Pharmacology (12.3)]. Examples Glutethimide and phenobarbital Intervention If a patient initiates or discontinues therapy with an enzyme inducer, dose adjustment of Doxercalciferol Injection may be necessary. Monitor intact PTH and serum calcium concentrations closely. Magnesium-containing Products Clinical Impact Concomitant administration of Doxercalciferol Injection and high doses of magnesium-containing products may increase the risk of hypermagnesemia. Examples Magnesium-containing products such as antacids Intervention Avoid use of magnesium-containing products and Doxercalciferol Injection in patients on chronic renal dialysis. • Cytochrome P450 inhibitors: Formation of the active doxercalciferol moiety may be hindered and may necessitate dosage adjustment. Monitor intact PTH and serum calcium concentrations closely.(7) • Enzyme inducers: Formation of the active doxercalciferol moiety may be affected and may necessitate dosage adjustment. Monitor intact PTH and serum calcium concentrations closely.(7) • Magnesium-containing products: Combined use may cause hypermagnesemia. Monitor serum magnesium concentrations more frequently and adjust dose as needed.(7)

6 ADVERSE REACTIONS The following adverse reactions are discussed in greater detail in another section of the label: • Hypercalcemia [see Warnings and Precautions (5.1)] • Serious Hypersensitivity Reactions [see Warnings and Precautions (5.3)] • Adynamic Bone Disease [see Warnings and Precautions (5.4)] The most common adverse reactions in patients with Stage 3 or 4 CKD (incidence >5%) were infection, urinary tract infection, chest pain, angina pectoris, constipation, dyspepsia, anemia, leucopenia, dehydration, edema, depression, hypertonia, insomnia, asthenia, paresthesia, cough increased, dyspnea, pruritus, sinusitis, and rhinitis.(6.1) The most common adverse reactions in patients with CKD on dialysis (incidence >5%) were headache, malaise, edema, nausea/vomiting, dyspnea, dizziness, pruritus, and bradycardia.(6.1) To report SUSPECTED ADVERSE REACTIONS, contact Gland Pharma at 864-879-9994 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 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. Doxercalciferol Injection Adverse reactions in patients with CKD on hemodialysis Doxercalciferol Injection has been studied in 70 patients with CKD on hemodialysis in two 12-week, open-label, single-arm, multicenter studies [see Clinical Studies (14.3)]. The incidence of hypercalcemia and hyperphosphatemia increased during therapy with Doxercalciferol Injection. Patients with higher pretreatment serum levels of calcium (>10.5 mg/dL) or phosphorus (>6.9 mg/dL) were more likely to experience hypercalcemia or hyperphosphatemia. There was no placebo group included in the studies of Doxercalciferol Injection. Adverse reactions in patients with CKD on hemodialysis receiving Doxercalciferol Injection are expected to be similar to those reported in placebo-controlled studies of Doxercalciferol capsules presented in Table 1. Table 1: Adverse Reactions Occurring in ≥2% Doxercalciferol Capsule-Treated Patients with CKD on Dialysis and Greater than Placebo in Two Double-Blind Clinical Studies Adverse Reaction* Doxercalciferol (n=61) % Placebo (n=61) % Edema 34 21 Malaise 28 20 Headache 28 18 Nausea/Vomiting 21 20 Dizziness 12 10 Dyspnea 12 7 Pruritus 8 7 Bradycardia 7 5 Anorexia 5 3 Dyspepsia 5 2 Arthralgia 5 0 Weight increase 5 0 Abscess 3 0 Sleep disorder 3 0 * A patient who reported the same medical term more than once was counted only once for that medical term. 6.2 Postmarketing Experience The following adverse reactions have been identified during postapproval use of Doxercalciferol Injection. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to estimate their frequency or to establish a causal relationship to drug exposure. Hypersensitivity reactions, including fatal outcome, have been reported in patients on hemodialysis following administration of Doxercalciferol Injection. Hypersensitivity reactions include anaphylaxis with symptoms of angioedema (involving face, lips, tongue and airways), hypotension, unresponsiveness, chest discomfort, shortness of breath, cardiopulmonary arrest, pruritus, and skin burning sensation.

8.1 Pregnancy Risk Summary The limited available data with Doxercalciferol Injection in pregnant women are insufficient to identify a drug-associated risk for major birth defects, miscarriage or adverse maternal or fetal outcomes. There are risks to the mother and fetus associated with chronic kidney disease in pregnancy [see Clinical Considerations]. In reproduction studies in rats and rabbits administered doxercalciferol during organogenesis at up to 20 mcg/kg/day and 0.1 mcg/kg/day, respectively (approximately 25 times (rats) and less than (rabbits) the maximum recommended human oral dose of 60 mcg/week based on mcg/m 2 body surface area), no adverse developmental effects were observed [see Data]. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Clinical Considerations Disease-associated maternal and/or embryo/fetal risk Chronic kidney disease in pregnancy increases the risk for maternal hypertension and preeclampsia, miscarriage, preterm delivery polyhydramnios, stillbirth, and low-birth-weight infants. Data Animal data There were no adverse effects on fetal development when doxercalciferol was administered at doses up to 20 mcg/kg/day in pregnant rats or doses up to 0.1 mcg/kg/day in pregnant rabbits during the period of organogenesis.