SPEVIGO

Dosage and Administration ( 2.2 , 2.3 , 2.5 ) 05/2025 Contraindications ( 4 ) 10/2025 Warnings and Precautions ( 5.3 ) 10/2025

1 INDICATIONS AND USAGE SPEVIGO is indicated for the treatment of generalized pustular psoriasis (GPP) in adults and pediatric patients 12 years of age and older and weighing at least 40 kg. SPEVIGO is an interleukin-36 receptor antagonist indicated for the treatment of generalized pustular psoriasis (GPP) in adults and pediatric patients 12 years of age and older and weighing at least 40 kg. ( 1 )

2 DOSAGE AND ADMINISTRATION Subcutaneous Dosage for Treatment of GPP When Not Experiencing a Flare Administer a subcutaneous loading dose of 600 mg, followed by 300 mg subcutaneously 4 weeks later and every 4 weeks thereafter. ( 2.3 ) Subcutaneous Use After Intravenous SPEVIGO for Treatment of GPP Flare: Four weeks after treatment with intravenous SPEVIGO, initiate or reinitiate subcutaneous SPEVIGO at a dose of 300 mg administered every 4 weeks. A loading dose is not required following treatment of a GPP flare with intravenous SPEVIGO. ( 2.3 ) See full prescribing information for preparation and administration instructions. ( 2.2 , 2.5 ) Intravenous Dosage for Treatment of GPP Flare Must be diluted before intravenous use. Administer as a single 900 mg dose by intravenous infusion over 90 minutes. If flare symptoms persist, may administer an additional intravenous 900 mg dose one week after the initial dose. ( 2.4 ) See full prescribing information for preparation and administration instructions and storage of the diluted solution. ( 2.2 , 2.5 ) 2.1 Testing and Procedures Prior to Treatment Initiation Evaluate patients for active or latent tuberculosis (TB) infection. SPEVIGO initiation is not recommended in patients with active TB infection. Consider initiating treatment of latent TB prior to initiation of SPEVIGO [see Warnings and Precautions (5.2) ] . Complete all age-appropriate vaccinations according to current immunization guidelines prior to initiating SPEVIGO for treatment of GPP [see Warnings and Precautions (5.4) ] . 2.2 Important Administration Information Subcutaneous Use for Treatment of GPP When Not Experiencing a Flare SPEVIGO prefilled syringes are for subcutaneous use for treatment of GPP when not experiencing a flare. When using SPEVIGO 300 mg/2 mL prefilled syringe: If the healthcare professional determines that it is appropriate, a patient 12 years of age or older may self-inject or the caregiver may administer the loading dose and the subsequent doses of SPEVIGO after proper training in subcutaneous injection technique. In pediatric patients 12 years of age and older, administer SPEVIGO under the supervision of an adult. When using SPEVIGO 150 mg/mL prefilled syringe: If required, the 600 mg subcutaneous loading dose of SPEVIGO is to be administered by a healthcare professional [see Dosage and Administration (2.3) ] . For subsequent 300 mg doses, if the healthcare professional determines that it is appropriate, a patient 12 years of age or older may self-inject or the caregiver may administer SPEVIGO after proper training in subcutaneous injection technique. In pediatric patients 12 years of age and older, administer SPEVIGO under the supervision of an adult. If a patient experiences a GPP flare while receiving subcutaneous SPEVIGO, the GPP flare may be treated with intravenous SPEVIGO [see Dosage and Administration (2.4) ] . Intravenous Use for Treatment of GPP Flare SPEVIGO vials are for intravenous use for treatment of GPP flare. Intravenous infusion of SPEVIGO is only to be administered by a healthcare professional in a healthcare setting. Prepare SPEVIGO intravenous infusion by diluting SPEVIGO single-dose vials [see Dosage and Administration (2.5) ] . Do not mix SPEVIGO with other medicinal products. 2.3 Recommended Subcutaneous Dosage for Treatment of GPP When Not Experiencing a Flare The recommended dosage of SPEVIGO for treatment of GPP when not experiencing a flare in adults and pediatric patients 12 years of age and older and weighing at least 40 kg is a loading dose of 600 mg followed by 300 mg administered subcutaneously 4 weeks later and every 4 weeks thereafter. Initiating or Reinitiating Subcutaneous SPEVIGO After Treatment of a GPP Flare with Intravenous SPEVIGO Four weeks after treatment of a GPP flare with intravenous SPEVIGO [see Dosage and Administration (2.4) ] , initiate or reinitiate subcutaneous SPEVIGO for treatment of GPP at a dose of 300 mg administered every 4 weeks. A subcutan …

3 DOSAGE FORMS AND STRENGTHS SPEVIGO is a colorless to slightly brownish-yellow, clear to slightly opalescent solution available as: For Subcutaneous Use Injection: 300 mg/2 mL (150 mg/mL) solution in a single-dose prefilled syringe ( 3 ) Injection: 150 mg/mL solution in a single-dose prefilled syringe ( 3 ) For Intravenous Use Injection: 450 mg/7.5 mL (60 mg/mL) solution in a single-dose vial ( 3 ) For subcutaneous use: Injection: 300 mg/2 mL (150 mg/mL) solution in a single-dose prefilled syringe Injection: 150 mg/mL in a single-dose prefilled syringe For intravenous use: Injection: 450 mg/7.5 mL (60 mg/mL) in a single-dose vial for dilution prior to intravenous infusion

4 CONTRAINDICATIONS SPEVIGO is contraindicated in patients with severe or life-threatening hypersensitivity to spesolimab-sbzo or to any of the excipients in SPEVIGO. Reported hypersensitivity reactions have included drug reaction with eosinophilia and systemic symptoms (DRESS) and anaphylaxis [see Warnings and Precautions (5.3) and Adverse Reactions (6) ] . Severe or life-threatening hypersensitivity to spesolimab-sbzo or to any of the excipients in SPEVIGO ( 4 )

6 ADVERSE REACTIONS The following adverse reactions are discussed in greater detail in other sections of the labeling: Infections [see Warnings and Precautions (5.1) ] Hypersensitivity and Infusion-Related Reactions [see Warnings and Precautions (5.3) ] Treatment of GPP When Not Experiencing a Flare: SPEVIGO has been associated with an increased incidence (≥9 cases per 100 patient-years) of injection site reaction, urinary tract infection, arthralgia, and pruritus. ( 6.1 ) Treatment of GPP Flare: The most common adverse reactions (≥5%) are asthenia and fatigue, headache, nausea, pruritus and prurigo, infusion site hematoma and bruising, and urinary tract infection. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact LEO Pharma, Inc. at 1-877-494-4536 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 clinical practice. Adverse Reactions with Intravenous SPEVIGO for Treatment of GPP Flare (Study Effisayil-1) SPEVIGO was studied in Study Effisayil-1, a randomized, double-blind, placebo-controlled study comparing a single intravenous 900 mg dose of SPEVIGO (n=35) with placebo (n=18) in subjects with generalized pustular psoriasis (GPP) flare. Subjects in either treatment group who continued to experience flare symptoms at Week 1 were eligible to receive a single open-label intravenous dose of 900 mg of SPEVIGO (second dose and first dose for subjects in the SPEVIGO and placebo groups, respectively). At Week 1, 12 (34%) subjects and 15 subjects (83%) in the SPEVIGO and placebo groups, respectively, received open-label SPEVIGO. After Week 1 to Week 12, subjects in either treatment group whose GPP flare reoccurred after achieving a clinical response were eligible to receive a single open-label rescue intravenous dose of 900 mg of SPEVIGO, with a maximum of 3 total doses of SPEVIGO throughout the study. Six subjects received a single open-label rescue dose of SPEVIGO. Thirty-six subjects received 1 dose of SPEVIGO, 13 subjects received 2 doses of SPEVIGO, and 2 subjects received 3 doses of SPEVIGO throughout the study [see Clinical Studies (14) ] . Subjects ranged in age from 21 to 69 years (mean age of 43 years); 45% were White and 55% were Asian; and 68% were female. Table 1 summarizes selected adverse reactions that occurred at a rate of at least 1% and at a higher rate in the intravenous SPEVIGO group than in the placebo group through Week 1. Table 1 Selected Adverse Reactions Occurring in ≥1% of the Intravenous SPEVIGO Group and More Frequently than in the Placebo Group through Week 1 in Subjects with GPP Flare (Study Effisayil-1) Adverse Reaction Intravenous SPEVIGO N = 35 n (%) Placebo N = 18 n (%) Asthenia and Fatigue 3 (9) 1 (6) Headache 3 (9) 1 (6) Nausea 2 (6) 0 Pruritus and prurigo 2 (6) 0 Infusion site hematoma and bruising 2 (6) 0 Urinary tract infection 2 (6) 0 Bacteremia 1 (3) 0 Bacteriuria 1 (3) 0 Cellulitis 1 (3) 0 Herpes dermatitis and oral herpes 1 (3) 0 Upper respiratory tract infection 1 (3) 0 Dyspnea 1 (3) 0 Eye edema 1 (3) 0 Urticaria 1 (3) 0 Specific Adverse Reactions Infections The most frequent adverse reactions that occurred in subjects treated with intravenous SPEVIGO were infections. During the 1-week placebo-controlled period in Study Effisayil-1, infections were reported in 14% of subjects treated with SPEVIGO compared with 6% of subjects treated with placebo. Serious infection (urinary tract infection) was reported in 1 subject (3%) treated with SPEVIGO and no subjects treated with placebo. Infections observed through Week 1 in Study Effisayil-1 in subjects treated with SPEVIGO were mild (29%) to moderate (71%). Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) Two cases of DRESS were reported in Study Effis …

8 USE IN SPECIFIC POPULATIONS 8.1 Pregnancy Risk Summary The limited data on the use of SPEVIGO in pregnant women are insufficient to inform a drug-associated risk of adverse pregnancy-related outcomes. Human IgG is known to cross the placental barrier; therefore, SPEVIGO may be transmitted from the mother to the developing fetus. In an animal reproduction study, intravenous administration of a surrogate antibody against IL36R in mice during the period of organogenesis did not elicit any reproductive toxicity (see Data ) . The background risk of major birth defects and miscarriage for the indicated population 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 2% to 4% and 15% to 20%, respectively. Data Animal Data Embryo-fetal development and pre- and postnatal development toxicity studies were performed in mice using a surrogate mouse specific IL36R antagonist monoclonal antibody. In the embryo-fetal development study, the surrogate was administered intravenously at doses up to 50 mg/kg to pregnant female mice twice weekly during the period of organogenesis. The surrogate was not associated with embryo-fetal lethality or fetal malformations. In the pre- and postnatal development toxicity study, the surrogate was administered intravenously at doses up to 50 mg/kg to pregnant female mice twice weekly from gestation day 6 through lactation day 18. There were no maternal effects observed. There were no treatment-related effects observed on postnatal developmental, neurobehavioral, or reproductive performance of offspring. 8.2 Lactation Risk Summary There are no data on the presence of spesolimab-sbzo in human milk, the effects on the breastfed infant, or the effects on milk production. Spesolimab-sbzo is a monoclonal antibody and is expected to be present in human milk. The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for SPEVIGO and any potential adverse effects on the breastfed infant from SPEVIGO or from the underlying maternal condition. 8.4 Pediatric Use The safety and effectiveness of SPEVIGO for the treatment of GPP have been established in pediatric patients 12 years of age and older and weighing at least 40 kg. Use of SPEVIGO for this indication is supported by data from a randomized, placebo-controlled study which included 6 pediatric subjects 14 to 17 years of age with a history of GPP treated with subcutaneous SPEVIGO (Study Effisayil-2) and evidence from an adequate and well-controlled study of intravenous SPEVIGO in adults with GPP (Study Effisayil-1), with additional pharmacokinetic analyses showing similar drug exposure levels in adults and pediatric subjects 12 years of age and older and weighing 40 kg or more [see Adverse Reactions (6.1) , Clinical Pharmacology (12.3) , and Clinical Studies (14) ] . The safety and effectiveness of SPEVIGO in pediatric patients younger than 12 years of age or in pediatric patients weighing less than 40 kg have not been established. 8.5 Geriatric Use There were 2 (6%) intravenous SPEVIGO-treated subjects 65 to 74 years of age and no subjects 75 years of age or older in Study Effisayil-1. There were 6 (7%) subcutaneous SPEVIGO-treated subjects 65 to 74 years of age and 1 (1%) subject 75 years of age in Study Effisayil-2. Clinical studies of SPEVIGO did not include sufficient numbers of subjects 65 years of age and older to determine whether they respond differently from younger adult subjects.

12.1 Mechanism of Action Spesolimab-sbzo is a humanized monoclonal immunoglobulin G1 antibody that inhibits interleukin-36 (IL-36) signaling by specifically binding to the IL36R. Binding of spesolimab-sbzo to IL36R prevents the subsequent activation of IL36R by its ligands (IL-36 α, β and γ) and downstream activation of pro-inflammatory and pro-fibrotic pathways. The precise mechanism linking reduced IL36R activity and the treatment of flares of GPP is unclear.

11 DESCRIPTION Spesolimab-sbzo, an interleukin-36 receptor antagonist, is a humanized monoclonal IgG1 antibody (mAb) against human IL-36R produced in Chinese hamster ovary (CHO) cells by recombinant DNA technology. Spesolimab-sbzo has a molecular weight of approximately 146 kDa. SPEVIGO (spesolimab-sbzo) injection is a sterile, preservative-free, colorless to slightly brownish-yellow, clear to slightly opalescent solution supplied in a single-dose prefilled syringe for subcutaneous use. Each 2 mL prefilled syringe contains 300 mg spesolimab-sbzo, arginine hydrochloride (10.6 mg), glacial acetic acid (0.64 mg), polysorbate 20 (0.80 mg), sodium acetate (6.50 mg), sucrose (102.8 mg), and Water for Injection, USP with a pH of 5.2 to 5.8. Each 1 mL prefilled syringe contains 150 mg spesolimab-sbzo, arginine hydrochloride (5.3 mg), glacial acetic acid (0.32 mg), polysorbate 20 (0.40 mg), sodium acetate (3.25 mg), sucrose (51.4 mg), and Water for Injection, USP with a pH of 5.2 to 5.8. SPEVIGO (spesolimab-sbzo) injection is a sterile, preservative-free, colorless to slightly brownish-yellow, clear to slightly opalescent solution supplied in a single-dose vial for intravenous use. Each 7.5 mL vial contains 450 mg spesolimab-sbzo, arginine hydrochloride (39.5 mg), glacial acetic acid (2.4 mg), polysorbate 20 (3.0 mg), sodium acetate (24.5 mg), sucrose (386 mg), and Water for Injection, USP with a pH of 5.2 to 5.8.

16 HOW SUPPLIED/STORAGE AND HANDLING How Supplied SPEVIGO (spesolimab-sbzo) injection is a sterile, preservative-free, colorless to slightly brownish-yellow, clear to slightly opalescent solution available as follows: Prefilled syringes (for subcutaneous use) NDC Number 0597-7705-41: Each carton contains one single-dose 300 mg/2 mL (150 mg/mL) prefilled syringe. NDC Number 0597-7705-72: Each carton contains two single-dose 300 mg/2 mL (150 mg/mL) prefilled syringes. NDC Number 0597-0620-20: Each carton contains two single-dose 150 mg/mL prefilled syringes. Single-dose vials (for intravenous use) NDC Number 0597-0035-10: Each carton contains two single-dose 450 mg/7.5 mL (60 mg/mL) glass vials. Storage and Handling Prefilled syringes 300 mg/2 mL: Store SPEVIGO prefilled syringes refrigerated between 2°C to 8°C (36°F to 46°F) in original carton to protect from light. Do not freeze. Do not use if frozen even if it has been thawed. If needed, SPEVIGO 300 mg/2 mL prefilled syringes may be stored at room temperature up to a maximum of 25°C (77°F) for up to 14 days in the original carton to protect from light. Discard SPEVIGO 300 mg/2 mL prefilled syringes if kept at room temperature for more than 14 days. 150 mg/mL: Store SPEVIGO prefilled syringes refrigerated between 2°C to 8°C (36°F to 46°F) in original carton to protect from light. Do not freeze. Do not use if frozen even if it has been thawed. Single-dose vials Store SPEVIGO vials refrigerated between 2°C to 8°C (36°F to 46°F) in original carton to protect from light. Do not freeze. Prior to use, may store unopened SPEVIGO vials at room temperature, 20°C to 25°C (68°F to 77°F), for up to 24 hours in the original carton to protect from light.