Denileukin diftitox

12.1 Mechanism of Action Denileukin diftitox-cxdl is a fusion protein designed to direct the cytocidal action of diphtheria toxin (DT) to cells which express the IL-2 receptor. After uptake into the cell, the DT fragment is cleaved and the free DT fragments inhibit protein synthesis, resulting in cell death. Denileukin diftitox-cxdl demonstrated the ability to deplete immunosuppressive regulatory T lymphocytes (Tregs) and antitumor activity through a direct cytocidal action on IL-2R-expressing tumors.

1 INDICATIONS AND USAGE LYMPHIR is indicated for the treatment of adult patients with relapsed or refractory Stage I-III cutaneous T-cell lymphoma (CTCL) after at least one prior systemic therapy. LYMPHIR is an IL2-receptor-directed cytotoxin indicated for the treatment of adult patients with relapsed or refractory Stage I-III cutaneous T-cell lymphoma (CTCL) after at least one prior systemic therapy. ( 1 )

2 DOSAGE AND ADMINISTRATION Delay start of treatment cycle if serum albumin level is below 3 g/dL. ( 2.1 ) The recommended dosage of LYMPHIR is 9 mcg/kg/day actual body weight administered as an intravenous infusion on Days 1 through 5 of a 21-day cycle. ( 2.2 ) Administer premedication as recommended. ( 2.3 ) See full prescribing information for preparation and administration instructions. ( 2.5 ) 2.1 Important Dosing Instructions Prior to starting each treatment cycle, assess hepatic and renal function. If serum albumin is less than 3 g/dL, delay administration of LYMPHIR until serum albumin is greater than or equal to 3 g/dL [see Warnings and Precautions ( 5.1 )] . 2.2 Recommended Dosage The recommended dosage of LYMPHIR is 9 mcg/kg/day actual body weight administered as an intravenous infusion over 60 minutes on Days 1 through 5 of a 21-day treatment cycle. Administer LYMPHIR until disease progression or unacceptable toxicity. 2.3 Recommended Premedications Administer premedications prior to starting a LYMPHIR infusion in Cycles 1 through 3, as outlined in Table 1, to reduce the risk of infusion-related reactions [see Warnings and Precautions ( 5.3 )] . Table 1. Premedication to be Administered to Patients Prior to LYMPHIR Infusion Treatment Cycle Premedication Dosage Administration Cycles 1-3 (optional thereafter) Antipyretic Oral acetaminophen 650 mg or per local institutional guidelines At least 30 minutes prior to infusion Antihistamine Diphenhydramine 25 mg intravenously or other antihistamine per local institutional guidelines At least 30 minutes prior to infusion Antiemetic Per institutional guidelines At least 30 minutes prior to infusion Hydration 250 to 500 mL 0.9% Sodium Chloride Injection intravenously (or other amount of fluid considered to be most appropriate for the subject’s condition) At least 30 minutes prior to infusion If patients experience a Grade 2 or higher infusion reaction, premedicate at least 30 minutes prior to each subsequent infusion with a systemic steroid such as dexamethasone 4 mg (or equivalent) via slow intravenous push, for at least 3 cycles. 2.4 Dosage Modifications for Adverse Reactions Dosage modifications for adverse reactions with LYMPHIR are shown in Table 2 below. Table 2: Recommended Dosage Modifications for Adverse Reactions Adverse Reaction Severity* Dosage Modification Capillary leak syndrome (CLS) [see Warnings and Precautions ( 5.1 )] Grade 2 Withhold LYMPHIR until CLS resolves to Grade 1. Grade 3 Withhold LYMPHIR and provide supportive care until CLS resolves to Grade 1. Resume LYMPHIR at 50% dose. Consider steroid premedication for subsequent infusions. Permanently discontinue upon recurrence. Grade 4 Permanently discontinue LYMPHIR. Visual impairment [see Warnings and Precautions ( 5.2 )] Grade 1 or 2 Consider withholding or discontinuing LYMPHIR as appropriate. Refer for ophthalmic evaluation. Grade 3 or 4 Withhold LYMPHIR until resolved to Grade 1 or baseline. Refer for ophthalmic evaluation. Permanently discontinue LYMPHIR if impairment does not resolve to Grade 1 or baseline. Infusion-related reactions [see Warnings and Precautions ( 5.3 )] Grade 2 or 3 Interrupt infusion and manage signs and symptoms. Administer steroid premedication prior to the subsequent doses of LYMPHIR [see Dosage and Administration ( 2.3 )] Continue steroid premedication for each dose in the next 3 cycles and optional thereafter [see Dosage and Administration ( 2.3 )] Grade 4 or Recurrent Grade 3 Permanently discontinue LYMPHIR. Hepatotoxicity [see Warnings and Precautions ( 5.4 )] Grade 2: ALT/AST 3 to 5 x upper limit of normal (ULN) Maintain LYMPHIR dose Monitor at least weekly until return to < 3 x ULN Grade 3: ALT/AST > 5 to 20 x ULN Withhold LYMPHIR and monitor at least weekly until return to < 3 x ULN Resume LYMPHIR at same dose (first occurrence) or at a reduced dose (50%) for subsequent occurrence Grade 4: ALT/AST > 20 x ULN Permanently discontinue LYMPHIR Other Adverse Reactions [see Adverse Reactions ( 6.1 )] Grade 3 Withhold LYMPHIR until resolution of toxicity to Grade 1 or baseline. Grade 4 Permanently discontinue LYMPHIR as appropriate. * Based on NCI CTCAE version 5.0 Restarting after Dosage Delay Due to Toxicity Time Since the Last Dose Administered Action for Next Dose Less than or equal to 16 days Restart a new cycle no earlier than 16 days after last dose of LYMPHIR More than 16 days Restart a new cycle of LYMPHIR More than 42 days Permanently discontinue LYMPHIR 2.5 Preparation and Administration Reconstitute and further dilute LYMPHIR prior to administration. Administer as an intravenous infusion over 60 minutes. Use aseptic technique to prepare LYMPHIR. LYMPHIR does not contain a preservative or anti-microbial agent. Care should be taken during preparation and administration of LYMPHIR to prevent inadvertent microbial contamination. Reconstitution Calculate the dose (mcg), total volume (mL) of solution required, and number of vials of LYMPHIR needed ba

6 ADVERSE REACTIONS The following adverse reactions are discussed in greater detail in other sections of the label: Capillary Leak Syndrome [see Warnings and Precautions ( 5.1 )] Visual Impairment [see Warnings and Precautions ( 5.2 )] Infusion-Related Reactions [see Warnings and Precautions ( 5.3 )] Hepatotoxicity [see Warnings and Precautions ( 5.4 )] The most common adverse reactions (≥20%), including laboratory abnormalities, are increased transaminases, albumin decreased, nausea, edema, hemoglobin decreased, fatigue, musculoskeletal pain, rash, chills, constipation, pyrexia, and capillary leak syndrome. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Citius Oncology, Inc. at 1-844-459-6744 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 pooled safety population described in the WARNINGS AND PRECAUTIONS reflect exposure to LYMPHIR as a single agent in 119 patients with CTCL across 3 clinical trials. Patients received treatment with LYMPHIR as an intravenous infusion at 9 mcg/kg daily from Day 1 through Day 5 of each 21-day cycle until disease progression or unacceptable toxicity. Among 119 patients who received LYMPHIR the median number of cycles received was 5 (range: 1 to 42), with 13% exposed for 6 months or longer. In this pooled safety population, the most common (≥ 20%) adverse reactions, including laboratory abnormalities, were increased transaminases (70%), albumin decreased (53%), nausea (40%), edema (35%), hemoglobin decreased (34%), fatigue (30%), musculoskeletal pain (26%), rash (23%), chills (22%), constipation (22%), pyrexia (21%), and capillary leak syndrome (20%). Relapsed or Refractory Stage I-III CTCL Study 302 The safety of LYMPHIR was evaluated in Study 302, an open-label, single-arm, multicenter trial that included 69 patients with relapsed or refractory Stage I-III CTCL [see Clinical Studies ( 14 )] . Patients received treatment with LYMPHIR 9 mcg/kg daily from Day 1 through Day 5 of each 21-day cycle. Treatment was administered until disease progression or unacceptable toxicity. The median number of LYMPHIR cycles was 6 (range: 1 to 42). The median age of patients was 64 years (range: 28 to 87 years), 49% were 65 years of age or older, 65% were men, 72% were White, 19% were Black or African American, 1.4% were Asian, and 14% were Hispanic or Latino. Serious adverse reactions occurred in 38% of patients who received LYMPHIR. Serious adverse reactions in > 2% of patients included capillary leak syndrome (10%), infusion-related reaction (9%), sepsis (7%), skin infection (2.9%), pyrexia (2.9%), and rash (2.9%). Permanent discontinuation of LYMPHIR due to an adverse reaction occurred in 12% of patients. Adverse reactions resulting in permanent discontinuation of LYMPHIR included capillary leak syndrome, infusion-related reaction, renal insufficiency, respiratory failure, and sepsis. Dosage interruptions of LYMPHIR due to an adverse reaction occurred in 38% of patients. Adverse reactions requiring dosage interruption of LYMPHIR included capillary leak syndrome, infusion-related reaction, weight increase, nausea, and tachycardia. Table 3 summarizes the adverse reactions in Study 302. Table 3: Adverse Reactions (≥ 10%) in Patients with Relapsed or Refractory Stage I-III CTCL Who Received LYMPHIR in Study 302 Adverse Reaction LYMPHIR N=69 All Grades (%) Grade 3 or 4 (%) Gastrointestinal disorders Nausea 43 1.4 # Diarrhea 19 0 Vomiting 13 0 Constipation 12 0 General disorders and administration site conditions Fatigue a 38 0 Edema b 33 1.4 Chills 27 1.4 Pyrexia 16 1.4 Musculoskeletal and connective tissue disorders Musculoskeletal pain c 27 2.9 Arthralgia 12 0 Nervous system disorders Headache d 25 0 Dizziness 13 0 Mental status changes e 13 0 Injury, poisoning and procedural complications Infusion-related reaction 25 6 Skin and subcutaneous tissue disorders Rash f 23 6 Pruritis 19 6 Vascular disorders Capillary leak syndrome 17 6 Metabolism and nutrition disorders Decreased appetite 13 1.4 Eye disorders Blurred vision 13 0 Investigations Weight increased 13 0 Infections and infestations Skin infection g 13 1.4 Renal and urinary disorders Renal insufficiency h 12 2.9 Psychiatric disorders Insomnia 10 0 # Only Grade 3 adverse reaction occurred a Includes fatigue, asthenia, and lethargy b Includes edema, edema peripheral, generalized edema, face edema, swelling face, peripheral swelling c Includes musculoskeletal pain, back pain, neck pain, pain in extremity, myalgia, bone pain d Includes headache, migraine e Includes amnesia, confusional state, delirium, memory impairment, disturbance in attention, somnolence, cognitive disorder f Includes rash, drug eruption, erythema, rash maculo-papula