Siltuximab

FDA Drug Information • Also known as: Sylvant

Brand Names
Sylvant
Drug Class
Interleukin-6 Antagonist [EPC]
Route
INTRAVENOUS
Dosage Form
INJECTION, POWDER, FOR SOLUTION
Product Type
HUMAN PRESCRIPTION DRUG

Description

11 DESCRIPTION Siltuximab is a human-mouse chimeric monoclonal antibody that binds human interleukin-6 (IL-6) and is produced by Chinese hamster ovary cells. SYLVANT (siltuximab) for injection is supplied as a sterile, white, preservative free, lyophilized powder in single-dose vials. Each SYLVANT 100 mg single-dose vial contains 100 mg siltuximab, 3.7 mg L-histidine (from L-histidine and L-histidine monohydrochloride monohydrate), 0.8 mg polysorbate 80, and 169 mg sucrose. Each SYLVANT 400 mg single-dose vial contains 400 mg siltuximab, 14.9 mg L-histidine (from L-histidine and L-histidine monohydrochloride monohydrate), 3.2 mg polysorbate 80, and 677 mg sucrose. Following reconstitution with Sterile Water for Injection, USP (per section 2.2), the resulting pH is approximately 5.2. The resulting solution contains 20 mg/mL siltuximab to be administered by intravenous infusion following dilution [see Dosage and Administration (2.2) ] .

What Is Siltuximab Used For?

1 INDICATIONS AND USAGE SYLVANT is indicated for the treatment of patients with multicentric Castleman's disease (MCD) who are human immunodeficiency virus (HIV) negative and human herpesvirus-8 (HHV-8) negative. SYLVANT is an interleukin-6 (IL-6) antagonist indicated for the treatment of patients with multicentric Castleman's disease (MCD) who are human immunodeficiency virus (HIV) negative and human herpesvirus-8 (HHV-8) negative. ( 1 ) Limitations of Use SYLVANT was not studied in patients with MCD who are HIV positive or HHV-8 positive because SYLVANT did not bind to virally produced IL-6 in a nonclinical study. Limitations of Use SYLVANT was not studied in patients with MCD who are HIV positive or HHV-8 positive because SYLVANT did not bind to virally produced IL-6 in a nonclinical study.

Dosage and Administration

2 DOSAGE AND ADMINISTRATION For intravenous infusion only. Administer as an 11 mg/kg dose given over 1 hour by intravenous infusion every 3 weeks. ( 2 ) 2.1 Recommended Dosage Administer SYLVANT 11 mg/kg over 1 hour as an intravenous infusion every 3 weeks until treatment failure. Perform hematology laboratory tests prior to each dose of SYLVANT therapy for the first 12 months and every 3 dosing cycles thereafter. If treatment criteria outlined in Table 1 are not met, consider delaying treatment with SYLVANT. Do not reduce dose. Table 1: Treatment Criteria Laboratory parameter Requirements before first SYLVANT administration Retreatment criteria Absolute Neutrophil Count ≥1.0 × 10 9 /L ≥1.0 × 10 9 /L Platelet count ≥75 × 10 9 /L ≥50 × 10 9 /L Hemoglobin SYLVANT may increase hemoglobin levels in MCD patients <17 g/dL <17 g/dL Do not administer SYLVANT to patients with severe infections until the infection resolves. Discontinue SYLVANT in patients with severe infusion related reactions, anaphylaxis, severe allergic reactions, or cytokine release syndromes. Do not reinstitute treatment. 2.2 Instructions for Preparation and Administration Use aseptic technique for reconstitution and preparation of dosing solution. Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit 1. Calculate the dose (mg), total volume (mL) of reconstituted SYLVANT solution required and the number of vials needed. A 21-gauge 1½ inch needle is recommended for preparation. Infusion bags (250 mL) must contain Dextrose 5% in Water and must be made of polyvinyl chloride (PVC), or polyolefin (PO), or polypropylene (PP), or polyethylene (PE). Alternatively PE bottles may be used. 2. Allow the vial(s) of SYLVANT to come to room temperature over approximately 30 minutes. SYLVANT should remain at room temperature for the duration of the preparation. 3. Aseptically reconstitute each SYLVANT vial as instructed in Table 2. Table 2: Reconstitution Instructions Strength Amount of Sterile Water for Injection, USP required for reconstitution Post-reconstitution concentration 100 mg vial 5.2 mL 20 mg/mL 400 mg vial 20 mL 20 mg/mL Gently swirl the reconstituted vials to aid the dissolution of the lyophilized powder. DO NOT SHAKE or SWIRL VIGOROUSLY. Do not remove the contents until all of the solids have been completely dissolved. The lyophilized powder should dissolve in less than 60 minutes. Once reconstituted, and prior to further dilution, inspect the vials for particulates and discoloration. Do not use if particles or solution discoloration are present or if visibly opaque. The reconstituted product should be kept for no more than two hours prior to addition into the infusion bag. 4. Dilute the reconstituted SYLVANT solution dose to 250 mL with sterile Dextrose 5% in Water by withdrawing a volume equal to the total calculated volume of reconstituted SYLVANT from the Dextrose 5% in Water,...

Side Effects (Adverse Reactions)

6 ADVERSE REACTIONS The following clinically significant adverse reactions are also discussed in other sections of the labeling: Concurrent active severe infections [see Warnings and Precautions (5.1) ] Infusion-related reactions and hypersensitivity [see Warnings and Precautions (5.3) ] Gastrointestinal perforation [see Warnings and Precautions (5.4) ] The most common adverse reactions (>10% of patients) were rash, pruritus, upper respiratory tract infection, increased weight, and hyperuricemia. To report SUSPECTED ADVERSE REACTIONS, contact Recordati Rare Diseases Inc., at 1-888-575-8344 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. Study 1, in MCD, was an international, multicenter, randomized Phase 2 study of every 3 week infusions comparing SYLVANT and best supportive care (BSC) to placebo and BSC. There were 53 patients randomized to the SYLVANT arm at a dosage of 11 mg/kg and 26 patients randomized to the placebo arm. Of the 26 placebo-treated patients, 13 patients subsequently crossed-over to receive SYLVANT. The median age was 48 years (range 20 to 78), 66% male, 48% Asian, 39% White, 4% Black or African American, 7% other. The patients randomized to SYLVANT received a median of 19 infusions (range 1 to 50) compared to patients randomized to placebo who received a median of 8 infusions (range 2 to 32). To control for disparate exposure between arms, Table 3 reports the per patient incidence of adverse reactions that occurred during the first 8 infusions. Adverse reactions that occurred >3% in the SYLVANT arm are presented. The most common adverse reactions (> 10% compared to placebo) during treatment with SYLVANT in the MCD clinical trial were rash, pruritus, upper respiratory tract infection, increased weight, and hyperuricemia. Table 3: Per Patient Incidence of Common Adverse Reactions in Study 1 During Initial 8 Infusions Body System/Adverse Reactions SYLVANT+BSC Best Supportive Care n=53 Placebo+BSC n=26 All Grades Grades 3-4 All Grades Grades 3-4 Skin disorders Rash (rash, rash generalized, rash maculo-papular, rash popular and rash pruritic) 15 (28%) 1 (2%) 3 (12%) 0 Pruritus 15 (28%) 0 2 (8%) 0 Skin hyperpigmentation 2 (4%) 0 0 0 Eczema 2 (4%) 0 0 0 Psoriasis 2 (4%) 0 0 0 Dry skin 2 (4%) 0 0 0 Infections Lower respiratory tract 4 (8%) 2 (4%) 1 (4%) 1 (4%) Upper respiratory tract 14 (26%) 1 (2%) 4 (15%) 1 (4%) Blood and lymphatic system disorders Thrombocytopenia 5 (9%) 2 (4%) 1 (4%) 1 (4%) General disorders Edema (general and localized) 14 (26%) 4 (8%) 7 (27%) 0 Gastrointestinal disorders Constipation 4 (8%) 0 1 (4%) 0 Metabolism Hypertriglyceridemia 4 (8%) 0 0 0 Hypercholesterolemia 2 (4%) 0 0 0 Hyperuricemia 6 (11%) 1 (2%) 0 0 Respiratory, thoracic and mediastinal disorders Oropharyngeal pain 4 (8%) 0 1 (4%) 0 Renal and urinary disorders Renal impairment 4 (8%) 0 0 0 Nervous system disorders Headache 4 (8%) 0 1 (4%) 0 Investigations Weight increased 10 (19%) 1 (2%) 0 0 Vascular disorders Hypotension 2 (4%) 1 (2%) Anaphylactic reaction 0 0 Study CNTO328MCD2002 (referred to as Study 2) (NCT01400503) was an open label, long term extension study of patients with MCD treated on prior trials. The median duration of siltuximab treatment was 5.52 years (range: 0.8 to 10.8 years); more than 50% of patients received siltuximab treatment for ≥5 years. The rate of serious or Grade ≥3 adverse events did not increase over time as a function of cumulative exposure. Other important adverse reactions reported in MCD clinical studies, all of which were very common, were: Infections and infestations: nasopharyngitis, urinary tract infection Blood and lymphatic system disorders: neutropenia Nervous system disorders: dizziness...

Drug Interactions

7 DRUG INTERACTIONS 7.1 Cytochrome P450 Substrates Cytochrome P450s in the liver are down regulated by infection and inflammation stimuli including cytokines such as IL-6. Inhibition of IL-6 signaling in patients treated with SYLVANT may restore CYP450 activities to higher levels leading to increased metabolism of drugs that are CYP450 substrates compared to metabolism prior to treatment with SYLVANT. Upon initiation or discontinuation of SYLVANT, in patients being treated with CYP450 substrates with a narrow therapeutic index, perform therapeutic monitoring of effect (e.g., warfarin) or drug concentration (e.g., cyclosporine or theophylline) as needed and adjust dose. The effect of SYLVANT on CYP450 enzyme activity can persist for several weeks after stopping therapy. Exercise caution when SYLVANT is co-administered with CYP3A4 substrate drugs where a decrease in effectiveness would be undesirable (e.g., oral contraceptives, lovastatin, atorvastatin).

Contraindications

4 CONTRAINDICATIONS Severe hypersensitivity reaction to siltuximab or any of the excipients in SYLVANT [see Warnings and Precautions (5.3) ] . Hypersensitivity reactions, including anaphylactic reaction, hypersensitivity, and drug hypersensitivity have been reported in patients treated with siltuximab. Severe hypersensitivity reaction to siltuximab or any of the excipients in SYLVANT. ( 4 )

Pregnancy and Breastfeeding

8.1 Pregnancy Risk-Summary In an animal reproduction study, intravenous administration of a human antibody to IL-6 to pregnant monkeys from the onset of organogenesis through delivery caused functional impairment in pregnant animals and in the offspring. Siltuximab and the human antibody to IL-6 crossed the placenta in monkeys ( see Data ). The limited available information on SYLVANT use during pregnancy is not sufficient to inform a drug-associated risk of major birth defects or miscarriage. Infants born to pregnant women treated with SYLVANT may be at increased risk of infection (see Clinical Considerations ). Advise pregnant women of the potential risk to a fetus. The estimated background risk 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 is 2% to 4% and of miscarriage is 15% to 20% of clinically recognized pregnancies. Clinical Considerations Fetal/Neonatal adverse reactions Monoclonal antibodies are transported across the placenta as pregnancy progresses, with the largest amount transferred during the third trimester. Infants born to pregnant women treated with SYLVANT may be at increased risk of infection. Consider the risks and benefits of administering live or live-attenuated vaccines to infants exposed to SYLVANT in utero [see Warnings and Precautions (5.2) ] . Data Animal Data In an embryo-fetal development study in cynomolgus monkeys, pregnant animals received intravenous doses of siltuximab of 9.2 or 46 mg/kg/week during gestation days (GD) 20 to 118, which includes the period of organogenesis. Fetuses were evaluated on GD 140, approximately 25 days prior to the natural birth. Exposures at the low and high dose after the 25 th administration were approximately 3 and 7 times, respectively, the human exposure based on AUC in patients with MCD at the recommended dose of 11 mg/kg every...

How Supplied

16 HOW SUPPLIED/STORAGE AND HANDLING 16.1 How Supplied SYLVANT (siltuximab) for injection is supplied as a sterile, white, preservative free, lyophilized powder in single-dose vials. Each SYLVANT vial is individually packaged in a carton: NDC: 73090-420-01 contains one 100 mg vial NDC: 73090-421-01 contains one 400 mg vial 16.2 Storage and Stability SYLVANT must be refrigerated at 2°C to 8°C (36°F to 46°F) in the original carton to protect from light. Do not freeze. Do not use SYLVANT beyond the expiration date (EXP) located on the carton and the vial.

About This Information

This drug information is sourced from FDA-approved labeling via the openFDA database. It is intended for educational and reference purposes only. This is not medical advice. Always consult your healthcare provider before making decisions about medication. Drug information may be updated by the FDA; check with your pharmacist for the most current information.

What are side effects?

Side effects are unwanted reactions that can occur when taking a medication. They range from mild (headache, nausea) to severe (allergic reactions, organ damage). Not everyone experiences side effects, and severity varies. Report any concerning side effects to your doctor.

What are drug interactions?

Drug interactions occur when a medication is affected by another drug, food, or supplement. Interactions can make medications less effective or cause dangerous side effects. Always tell your doctor about all medications and supplements you take.