DEFITELIO

Defibrotide sodium is an oligonucleotide mixture with profibrinolytic properties. The chemical name of defibrotide sodium is polydeoxyribonucleotide, sodium salt. Defibrotide sodium is a polydisperse mixture of predominantly single-stranded (ss) polydeoxyribonucleotide sodium salts derived from porcine intestinal tissue having a mean weighted molecular weight of 14-19 kDa, and a potency of 27-39 and 28-38 biological units per mg as determined by two separate assays measuring the release of a product formed by contact between defibrotide sodium, plasmin and a plasmin substrate. The primary structure of defibrotide sodium is shown below. DEFITELIO (defibrotide sodium) injection is a clear, light yellow to brown, sterile, preservative-free solution in a single-patient-use vial for intravenous use. Each milliliter of the injection contains 80 mg of defibrotide sodium and 10 mg of Sodium Citrate, USP, in Water for Injection, USP. Hydrochloric Acid, NF, and/or Sodium Hydroxide, NF, may have been used to adjust pH to 6.8-7.8. chemical structure

DEFITELIO is indicated for the treatment of adult and pediatric patients with hepatic veno-occlusive disease (VOD), also known as sinusoidal obstruction syndrome (SOS), with renal or pulmonary dysfunction following hematopoietic stem-cell transplantation (HSCT). DEFITELIO is indicated for the treatment of adult and pediatric patients with hepatic veno-occlusive disease (VOD), also known as sinusoidal obstruction syndrome (SOS), with renal or pulmonary dysfunction following hematopoietic stem-cell transplantation (HSCT). ( 1 )

• Administer DEFITELIO 6.25 mg/kg every 6 hours given as a 2-hour intravenous infusion. ( 2.1 ) • Treat for a minimum of 21 days. If after 21 days signs and symptoms of VOD have not resolved, continue treatment until resolution. ( 2.1 ) 2.1 Recommended Dosage The recommended dosage of DEFITELIO for adult and pediatric patients is 6.25 mg/kg every 6 hours given as a 2‑hour intravenous infusion. The dose should be based on patient’s baseline body weight, defined as the patient’s weight prior to the preparative regimen for HSCT. Administer DEFITELIO for a minimum of 21 days. If after 21 days signs and symptoms of hepatic VOD have not resolved, continue DEFITELIO until resolution of VOD or up to a maximum of 60 days. 2.2 Administration Instructions • DEFITELIO must be diluted prior to infusion [see Dosage and Administration (2.4) ] . • Prior to administration of DEFITELIO, confirm that the patient is not experiencing clinically significant bleeding and is hemodynamically stable on no more than one vasopressor [see Warnings and Precautions (5.1) ] . • Administer DEFITELIO by constant intravenous infusion over a 2-hour period. • Administer the diluted DEFITELIO solution using an infusion set equipped with a 0.2 micron in-line filter. Flush the intravenous administration line (peripheral or central) with 5% Dextrose Injection, USP or 0.9% Sodium Chloride Injection, USP immediately before and after administration. • Do not co‑administer DEFITELIO and other intravenous drugs concurrently within the same intravenous line. 2.3 Treatment Modification Treatment modification, including temporary or permanent discontinuation of DEFITELIO, should follow the recommendations in Table 1. Table 1: Treatment Modifications for Toxicity or Invasive Procedures Event Recommended Action Hypersensitivity Reaction Severe or life-threatening (anaphylaxis) 1. Discontinue DEFITELIO permanently; do not resume treatment. Bleeding Persistent, severe or potentially life-threatening 1. Withhold DEFITELIO. 2. Treat the cause of bleeding and give supportive care as clinically indicated. 3. Consider resuming treatment (at the same dose and infusion volume) when bleeding has stopped and the patient is hemodynamically stable. Recurrent significant bleeding 1. Discontinue DEFITELIO permanently; do not resume treatment. Invasive Procedures 1. There is no known reversal agent for the profibrinolytic effects of DEFITELIO. Discontinue DEFITELIO infusion at least 2 hours prior to an invasive procedure. 2. Resume DEFITELIO treatment after the procedure as soon as any procedure-related risk of bleeding is resolved. 2.4 Preparation Instructions Dilute DEFITELIO in 5% Dextrose Injection, USP or 0.9% Sodium Chloride Injection, USP to a concentration of 4 mg/mL to 20 mg/mL. Administer the diluted solution over 2 hours. Vials contain no antimicrobial preservatives and are intended for a single-patient-use only. Partially used vials should be discarded. Use the diluted DEFITELIO solution within 4 hours if stored at room temperature or within 24 hours if stored under refrigeration. Up to four doses of DEFITELIO solution may be prepared at one time, if refrigerated. Preparation Instructions: • Determine the dose (mg) and number of vials of DEFITELIO based on the individual patient’s baseline weight (weight prior to the preparative regimen for HSCT). • Calculate the volume of DEFITELIO needed, withdraw this amount from the vial(s) and add it to the infusion bag containing 0.9% Sodium Chloride Injection or 5% Dextrose Injection for each dose to make a final concentration of 4 mg/mL to 20 mg/mL. • Gently mix the solution for infusion. • Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit. Only clear solutions without visible particles should be used. Depending on the type and amount of diluent, the color of the diluted solution may vary from colorless to light yellow.

The use of DEFITELIO is contraindicated in the following conditions: • Concomitant administration with systemic anticoagulant or fibrinolytic therapy [see Warnings and Precautions (5.1) ] • Known hypersensitivity to DEFITELIO or to any of its excipients [see Warnings and Precautions (5.2) ] • Concomitant administration with systemic anticoagulant or fibrinolytic therapy. ( 4 ) • Known hypersensitivity to DEFITELIO or to any of its excipients. ( 4 )

The following adverse reactions are discussed in greater detail in other sections of the labeling: • Hemorrhage [see Warnings and Precautions (5.1) ] • Hypersensitivity Reactions [see Warnings and Precautions (5.2) ] The most common adverse reactions (incidence ≥10% and independent of causality) with DEFITELIO treatment were hypotension, diarrhea, vomiting, nausea, and epistaxis. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Jazz Pharmaceuticals, Inc. at 1-800-520-5568 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. The safety of DEFITELIO was determined in 176 adult and pediatric patients with hepatic VOD with pulmonary and/or renal dysfunction following HSCT who were treated with DEFITELIO 6.25 mg/kg every 6 hours [see Clinical Studies (14) ] . Patients were excluded from these trials if at time of study entry they had significant acute bleeding, active grades B-D graft-versus-host disease, or a requirement for multiple vasopressors to provide blood pressure support. For the purposes of adverse event recording in the clinical trials, events were not required to be reported if they were related to the hepatic VOD, or if they were expected to occur after hematopoietic stem-cell transplantation (HSCT), unless they were serious or Grade 4-5. The median age of the safety population was 25 years (range: 1 month to 72 years), and 63% were ≥17 years of age. A total of 60% of patients were male, 78% were white, 89% had undergone allogeneic HSCT, and the underlying diagnosis was acute leukemia for 43%. At study entry, 13% were dialysis dependent and 18% were ventilator dependent. DEFITELIO was administered for a median of 21 days (range: 1 to 83 days). Information about adverse reactions resulting in permanent discontinuation of DEFITELIO was available for 102 patients, and 35 (34%) of these patients had an adverse reaction with permanent discontinuation. Adverse reactions leading to permanent discontinuation included pulmonary alveolar hemorrhage in 5 (5%) patients; pulmonary hemorrhage, hypotension, catheter site hemorrhage, and multi-organ failure, each in 3 (3%) patients; and cerebral hemorrhage and sepsis, each in 2 (2%) patients. Information about adverse reactions of any grade was available for all 176 patients. The most common adverse reactions (incidence ≥10% and independent of causality) were hypotension, diarrhea, vomiting, nausea, and epistaxis. The most common serious adverse reactions (incidence ≥5% and independent of causality) were hypotension (11%) and pulmonary alveolar hemorrhage (7%). Hemorrhage events of any type and any grade were reported for 104 (59%) of the patients, and the events were grade 4-5 in 35 (20%). Table 2 presents adverse reactions independent of causality ≥10% any grade or Grade 4/5 ≥2% reported in patients treated with DEFITELIO. Table 2: Adverse Reactions a ≥10% or Grade 4-5 Adverse Reactions ≥2% DEFITELIO (n=176) Adverse Reaction a Any grade Grade 4-5 b Hypotension 65 (37%) 12 (7%) Diarrhea 43 (24%) 0 Vomiting 31 (18%) 0 Nausea 28 (16%) 0 Epistaxis 24 (14%) 0 Pulmonary alveolar hemorrhage 15 (9%) 12 (7%) Gastrointestinal hemorrhage 15 (9%) 5 (3%) Sepsis 12 (7%) 9 (5%) Graft versus host disease 11 (6%) 7 (4%) Lung infiltration 10 (6%) 5 (3%) Pneumonia 9 (5%) 5 (3%) Pulmonary hemorrhage 7 (4%) 4 (2%) Infection 6 (3%) 4 (2%) Hemorrhage intracranial 5 (3%) 4 (2%) Hyperuricemia 4 (2%) 4 (2%) Cerebral hemorrhage c 3 (2%) 3 (2%) a Excludes events considered to be due to the underlying disease: multi-organ failure, veno-occlusive disease, respiratory failure, renal failure, and hypoxia b Adverse reactions considered life-threatening or fatal c Cerebral hemorrhage has been included in the table due to clinical relevance

Antithrombotic Agents DEFITELIO may enhance the pharmacodynamic activity of antithrombotic/fibrinolytic drugs such as heparin or alteplase. Concomitant use of DEFITELIO with antithrombotic or fibrinolytic drugs is contraindicated because of an increased risk of hemorrhage [see Contraindications (4) ] . • DEFITELIO may enhance the activity of antithrombotic/fibrinolytic drugs. ( 7 )