SYLVANT: Uses, Dosage & Side Effects
A monoclonal antibody targeting interleukin-6 (IL-6) for the treatment of multicentric Castleman disease in HIV-negative and HHV-8-negative adults
SYLVANT (siltuximab) is a chimeric monoclonal antibody that targets interleukin-6 (IL-6), a key cytokine driving the pathology of multicentric Castleman disease (MCD). It is the first and only therapy specifically approved for the treatment of MCD in adult patients who are HIV-negative and HHV-8-negative. By binding to and neutralizing IL-6, SYLVANT blocks the inflammatory signaling cascade responsible for the abnormal growth of lymph node cells, systemic symptoms such as fatigue, night sweats, and weight loss, and laboratory abnormalities including elevated C-reactive protein (CRP). SYLVANT is administered as an intravenous infusion every three weeks in a hospital or clinic setting and has demonstrated durable tumor and symptomatic responses in clinical trials.
Quick Facts: SYLVANT
Key Takeaways
- SYLVANT (siltuximab) is the only drug specifically approved for multicentric Castleman disease (MCD) in patients who are HIV-negative and HHV-8-negative, targeting the overproduction of interleukin-6 (IL-6) that drives the disease.
- It is administered as an intravenous infusion of 11 mg/kg every 3 weeks and treatment continues for as long as the patient benefits clinically, with some patients maintaining response for years.
- SYLVANT can mask signs of infection by suppressing fever and CRP levels, so patients and doctors must remain vigilant for infections even when inflammatory markers appear normal during treatment.
- Common side effects include upper respiratory infections, itching, rash, elevated blood lipids, high blood pressure, gastrointestinal symptoms, and reduced blood cell counts (neutropenia and thrombocytopenia).
- Women of childbearing potential must use effective contraception during treatment and for 3 months after the last dose; the safety of SYLVANT during pregnancy and breastfeeding has not been established.
What Is SYLVANT and What Is It Used For?
SYLVANT contains the active substance siltuximab, a chimeric (human-murine) monoclonal antibody. Monoclonal antibodies are laboratory-engineered proteins designed to recognize and bind to a specific target in the body. In the case of SYLVANT, the target is interleukin-6 (IL-6), a cytokine – a small signaling protein – that plays a central role in inflammation, immune regulation, and cell growth. IL-6 is produced by many cell types and is normally involved in the body’s response to infection and tissue damage. However, when IL-6 is produced in excessive amounts, as occurs in multicentric Castleman disease, it drives a cascade of harmful effects.
Multicentric Castleman disease (MCD) is a rare lymphoproliferative disorder characterized by the overgrowth of cells in lymph nodes at multiple sites throughout the body. Unlike unicentric Castleman disease, which affects a single lymph node region and can usually be cured by surgical removal, MCD involves widespread lymph node enlargement and is associated with significant systemic symptoms. Patients with MCD often experience debilitating fatigue, night sweats, fever, unintentional weight loss, loss of appetite, and a general feeling of being unwell. Laboratory abnormalities are common and include elevated C-reactive protein (CRP), anemia, low albumin levels, and elevated immunoglobulin levels.
The pathogenesis of MCD is closely linked to excessive IL-6 production. In patients who are HHV-8-negative (also referred to as idiopathic MCD or iMCD), the source of the excessive IL-6 is not entirely understood, but it is thought to originate from the abnormal cells within the affected lymph nodes or from dysregulated immune cells. This overproduction of IL-6 stimulates the growth and activation of B cells and plasma cells, promotes the release of acute-phase reactants such as CRP and fibrinogen from the liver, and contributes to the systemic inflammatory symptoms that characterize the disease. The elevated IL-6 also drives the production of vascular endothelial growth factor (VEGF), which can lead to increased blood vessel formation within enlarged lymph nodes.
By binding specifically and with high affinity to human IL-6, siltuximab forms stable antibody-cytokine complexes that prevent IL-6 from binding to its receptor (both soluble and membrane-bound IL-6 receptors). This effectively neutralizes the biological activity of IL-6 and blocks the downstream signaling pathways, including the JAK-STAT3 pathway, that are responsible for the abnormal cell proliferation and inflammatory symptoms. As a result, treatment with SYLVANT leads to a reduction in lymph node size, improvement in systemic symptoms, normalization of inflammatory markers (particularly CRP), and improvement in hemoglobin and albumin levels.
SYLVANT is approved by the European Medicines Agency (EMA), the U.S. Food and Drug Administration (FDA), and regulatory authorities in numerous other countries for the treatment of MCD in adult patients who are HIV-negative and HHV-8-negative. It is important to note that SYLVANT is not indicated for HHV-8-positive MCD or HIV-associated MCD, as the disease mechanism in these cases is fundamentally different – in HHV-8-associated MCD, the virus itself produces a viral homologue of IL-6 (vIL-6) that is not bound by siltuximab.
Castleman disease is named after Dr. Benjamin Castleman, who first described the condition in 1956. It is not a cancer, although it involves abnormal lymph node growth. MCD is estimated to affect approximately 5,000–6,000 people per year in the United States. The idiopathic form (HIV-negative, HHV-8-negative) accounts for roughly half of all MCD cases. Without treatment, MCD can lead to serious organ dysfunction and a significantly reduced quality of life. SYLVANT has transformed the management of iMCD by providing the first targeted therapy for this condition.
What Should You Know Before Receiving SYLVANT?
Contraindications
SYLVANT must not be used in patients who have a known severe hypersensitivity (allergic reaction) to siltuximab or to any of the excipients in the formulation, including histidine, histidine hydrochloride monohydrate, polysorbate 80, and sucrose. If you have ever experienced a serious allergic reaction to a monoclonal antibody therapy, inform your doctor before starting SYLVANT.
Warnings and Precautions
Before and during treatment with SYLVANT, discuss the following with your doctor:
SYLVANT suppresses IL-6 activity, which plays a key role in the body’s inflammatory response. This means SYLVANT can mask the typical signs and symptoms of acute inflammation, including suppressing fever and reducing acute-phase reactants such as C-reactive protein (CRP). You may have a serious infection without displaying the usual warning signs. Report any symptoms such as cough, flu-like feelings, malaise, warm or red skin, or any other unusual symptoms to your doctor immediately, even if you do not have a fever.
- Active infections: If you currently have an infection, your doctor should treat the infection before starting or continuing SYLVANT. SYLVANT can reduce your body’s ability to detect and fight infections, and existing infections may worsen during treatment. Serious infections, including pneumonia and sepsis, have been reported in patients treated with SYLVANT.
- Vaccinations: Do not receive live vaccines during treatment with SYLVANT. Some vaccines may not work as effectively while you are being treated. If you need vaccination, discuss this with your doctor before starting treatment. Ensure that all recommended vaccinations are up to date before beginning SYLVANT therapy.
- Elevated blood lipids (hypertriglyceridemia): SYLVANT can increase triglyceride levels in the blood. Your doctor will monitor your blood lipid levels and may prescribe medication to manage elevated triglycerides if necessary.
- Gastrointestinal perforation: If you have a condition that increases your risk of gastrointestinal perforation (a hole or tear in the wall of the stomach or intestines), such as peptic ulcers, diverticular disease, or recent abdominal surgery, tell your doctor. Signs of perforation include worsening abdominal pain, nausea, changes in bowel habits, and fever. Seek immediate medical attention if you experience these symptoms.
- Liver disease: If you have liver disease or abnormal liver function tests, your doctor will monitor your liver function closely during treatment. SYLVANT can affect liver enzyme levels.
- Infusion reactions and allergic reactions: Severe allergic reactions, including anaphylaxis, can occur during or after SYLVANT infusions. Symptoms may include difficulty breathing, chest tightness, wheezing, severe dizziness or lightheadedness, swelling of the lips, or skin rash. If you experience any of these symptoms, tell your healthcare team immediately. Treatment may need to be stopped, and your doctor may pre-medicate you before future infusions.
- Blood cell counts: SYLVANT can decrease white blood cells (neutropenia) and platelets (thrombocytopenia). Your doctor will perform regular blood tests to monitor your blood cell counts. If your counts drop below safe levels, treatment may need to be delayed.
Pregnancy and Breastfeeding
SYLVANT is not recommended during pregnancy. It is unknown whether siltuximab can cause harm to an unborn baby or affect a pregnant woman. Women of childbearing potential should use effective contraception during treatment with SYLVANT and for at least 3 months after the last dose.
In certain cases where a pregnant woman has MCD that requires treatment, the doctor may advise that the benefit of SYLVANT to the mother outweighs the potential risks to the fetus. These risks include an increased susceptibility to infections and restrictions on the use of certain live vaccines in infants whose mothers received SYLVANT during pregnancy. The decision should be made on an individual basis with careful consideration of both maternal and fetal health.
It is not known whether siltuximab passes into human breast milk. Because many antibodies are excreted in breast milk, a decision should be made whether to discontinue breastfeeding or to discontinue SYLVANT, taking into account the importance of the treatment for the mother.
Driving and Operating Machinery
SYLVANT is unlikely to affect your ability to drive or operate machinery. However, if you experience dizziness or fatigue during treatment, which are known side effects, you should avoid driving or operating machinery until these symptoms have resolved.
Children and Adolescents
The safety and efficacy of SYLVANT have not been established in children and adolescents (under 18 years of age). Therefore, SYLVANT should not be given to this age group.
How Does SYLVANT Interact with Other Drugs?
Drug interactions with SYLVANT are primarily related to its effect on cytochrome P450 (CYP450) enzymes. In inflammatory conditions with elevated IL-6 levels, the activity of CYP450 enzymes (particularly CYP1A2, CYP2C9, CYP2C19, and CYP3A4) is suppressed. When SYLVANT neutralizes IL-6, the levels of these enzymes may return to normal or increase, which can accelerate the metabolism of drugs that are substrates of these enzymes. This means that the blood levels of certain medications may decrease, potentially reducing their effectiveness.
This interaction is particularly important for drugs with a narrow therapeutic index – medications where small changes in blood levels can lead to treatment failure or toxicity. Your doctor should monitor the levels and effects of any such medications you are taking and adjust doses as needed when starting or stopping SYLVANT.
Major Interactions
| Interacting Drug | Effect | Clinical Significance |
|---|---|---|
| Warfarin (CYP2C9 substrate) | Increased warfarin metabolism; lower blood levels may reduce anticoagulant effect | Monitor INR closely; dose adjustment may be needed |
| Ciclosporin (CYP3A4 substrate) | Increased ciclosporin metabolism; lower blood levels may risk organ rejection in transplant patients | Monitor ciclosporin trough levels; adjust dose as necessary |
| Theophylline (CYP1A2 substrate) | Increased theophylline metabolism; lower blood levels may reduce asthma control | Monitor theophylline levels; adjust dose to maintain therapeutic range |
| Oral contraceptives (CYP3A4 substrates) | Increased metabolism may reduce contraceptive efficacy | Consider additional or alternative contraception methods |
| Live vaccines (e.g., MMR, varicella, BCG) | Risk of vaccine-strain infection due to immunosuppressive effects | Avoid during treatment; complete vaccinations before starting SYLVANT |
Minor Interactions
| Interacting Drug | Effect | Clinical Significance |
|---|---|---|
| Omeprazole (CYP2C19 substrate) | Possible increased metabolism, modestly lower blood levels | Generally well tolerated; monitor for symptom recurrence |
| Statins (some are CYP3A4 substrates) | Potential changes in statin blood levels | Monitor lipid levels and adjust statin dose if needed |
| Other immunosuppressive agents | Additive immunosuppression, increased infection risk | Monitor closely for infections; consider prophylactic measures |
| Corticosteroids | Commonly used in MCD management; no specific negative interaction | May be co-administered; SYLVANT may allow corticosteroid tapering |
It is essential to inform your doctor about all medications, supplements, and herbal products you are taking before starting SYLVANT. This includes prescription drugs, over-the-counter medications, and dietary supplements. Your doctor may need to adjust doses of your current medications or monitor their effects more closely during SYLVANT treatment.
The drug interaction mechanism of SYLVANT is unique: by normalizing IL-6 levels, it restores CYP450 enzyme activity that was previously suppressed by inflammation. This is the opposite of most drug-drug interactions, where one drug inhibits the metabolism of another. The clinical impact is greatest for narrow therapeutic index drugs and during the first few weeks of SYLVANT therapy.
What Is the Correct Dosage of SYLVANT?
SYLVANT is always administered by a doctor or nurse as an intravenous infusion in a hospital or clinic setting. The dose is calculated individually based on your body weight. You will be monitored during and after each infusion for potential side effects, particularly allergic and infusion-related reactions.
Adults
Standard Dosing for Multicentric Castleman Disease
Dose: 11 mg per kilogram of body weight
Route: Intravenous infusion over approximately 1 hour
Frequency: Once every 3 weeks (21-day cycle)
Duration: Treatment continues until you and your doctor agree that you are no longer benefiting from the therapy
For example, a patient weighing 70 kg would receive a dose of 770 mg (70 × 11 mg) at each infusion. The powder must be reconstituted and diluted before administration.
Treatment Decisions
Your doctor will assess your response to SYLVANT at regular intervals. The key measures of treatment effectiveness include reduction in lymph node size (assessed by imaging such as CT scans), improvement in disease-related symptoms (fatigue, night sweats, fever, weight loss), normalization of inflammatory markers (especially CRP), and improvement in blood counts (hemoglobin, platelets). Treatment with SYLVANT is intended to be ongoing as long as clinical benefit is maintained. In the pivotal clinical trial, many patients continued to respond for years.
If you fail to achieve a symptomatic response or your disease progresses despite treatment, your doctor may consider discontinuing SYLVANT and exploring alternative therapeutic approaches. The Castleman Disease Collaborative Network (CDCN) provides evidence-based treatment guidelines that your doctor may follow in making these decisions.
Dose Delays and Modifications
Your doctor may need to delay your infusion in the following situations:
- Active infection: SYLVANT should be withheld if you develop an infection, as IL-6 blockade can impair the immune response. Treatment can be resumed once the infection has been adequately treated.
- Neutropenia: If your white blood cell count (absolute neutrophil count) drops below 1.0 × 109/L, treatment should be delayed until counts recover above this threshold.
- Thrombocytopenia: If your platelet count drops below 50 × 109/L, treatment should be delayed until counts improve sufficiently.
- Infusion reactions: If you experience an infusion reaction, your doctor will manage it appropriately and decide whether to continue, slow down, or discontinue the infusion.
There are no specific dose reduction recommendations for SYLVANT. If dose modifications are needed, they generally involve delaying treatment rather than reducing the dose amount.
Children
SYLVANT is intended for use in adult patients only. The safety and efficacy of siltuximab in children and adolescents below 18 years of age have not been established. SYLVANT should not be used in this population.
Missed Dose
If you miss a scheduled infusion, contact your doctor as soon as possible to reschedule. It is important to maintain the regular 3-week dosing schedule to ensure consistent IL-6 blockade and optimal disease control. Do not receive a double dose to make up for a missed infusion.
Overdose
Since SYLVANT is administered by healthcare professionals in a controlled setting, overdose is unlikely. There is no specific antidote for siltuximab. In the event of an overdose, the patient should be monitored closely and treated symptomatically. The potential effects of an overdose are not fully known, but could theoretically include exaggerated immunosuppression and increased susceptibility to infections.
How SYLVANT Is Prepared and Given
SYLVANT is supplied as a white powder in glass vials containing 100 mg of siltuximab. Before administration, each vial is reconstituted with 5.2 mL of sterile water for injection to produce a solution containing 20 mg/mL. The reconstituted solution is then diluted in a 250 mL infusion bag containing 5% glucose (dextrose) solution. The required number of vials is calculated based on the patient’s weight and the 11 mg/kg dose.
The diluted solution is infused intravenously over approximately 1 hour using an administration set with a 0.2 micrometer polyethersulfone (PES) inline filter. SYLVANT should not be infused simultaneously with other medications through the same intravenous line. The reconstituted solution should not be stored for more than 2 hours before being added to the infusion bag, and the infusion should be completed within 6 hours of preparation.
SYLVANT is always prepared and administered by trained healthcare professionals in a hospital or specialized clinic setting. You will not self-administer this medication at home. Each infusion is carefully calculated based on your body weight and you will be monitored throughout the infusion for potential reactions.
What Are the Side Effects of SYLVANT?
Like all medicines, SYLVANT can cause side effects, although not everyone experiences them. The following side effects have been reported during clinical trials and post-marketing surveillance. Your medical team will monitor you during treatment and help manage any side effects that arise. It is important to report any new or worsening symptoms to your doctor promptly.
Serious Side Effects Requiring Immediate Attention
Tell your doctor or nurse immediately if you notice any signs of a severe allergic reaction during or after your infusion. Signs may include: difficulty breathing, chest tightness, wheezing, severe dizziness or lightheadedness, swelling of the lips, tongue, or face, or widespread skin rash. These reactions can be life-threatening and require immediate medical intervention.
Very Common
May affect more than 1 in 10 people
- Decreased white blood cell count (neutropenia)
- Decreased platelet count (thrombocytopenia)
- Itching (pruritus)
- Rash and eczema
- High levels of blood fats (hypertriglyceridemia)
- High blood uric acid levels (hyperuricemia), which may cause gout
- Abnormal kidney function tests
- Swelling of arms, legs, neck, or face (peripheral edema)
- High blood pressure (hypertension)
- Upper respiratory tract infections (nose, sinuses, or throat)
- Urinary tract infection
- Common cold (nasopharyngitis)
- Sore throat (oropharyngeal pain)
- Abdominal pain or discomfort, constipation, diarrhea, heartburn (gastroesophageal reflux), mouth ulcers, nausea, vomiting
- Dizziness
- Headache
- Joint pain (arthralgia), pain in arms or legs
- Weight gain
Common
May affect up to 1 in 10 people
- High cholesterol levels in the blood (hypercholesterolemia)
Important Safety Considerations
Because SYLVANT blocks IL-6, it can suppress the normal inflammatory response. This means that some side effects, particularly infections, may present atypically. For example, you may not develop a fever even when you have a significant bacterial infection, because IL-6 is a major driver of the fever response. Similarly, your CRP levels may remain low despite an active infection. For this reason, it is essential to report any symptoms that might indicate an infection – including cough, cold symptoms, malaise, warm or red skin, or general feeling of being unwell – to your doctor promptly, even if your temperature is normal.
Infusion-related reactions have been reported in patients receiving SYLVANT. These can range from mild symptoms such as flushing and headache to more serious reactions including back pain, chest discomfort, nausea, and, rarely, severe anaphylactic reactions. Your healthcare team will monitor you during each infusion and may slow down or stop the infusion if a reaction occurs. If you have previously experienced an infusion reaction, pre-medications such as antihistamines, corticosteroids, or acetaminophen may be given before your next infusion.
Long-term treatment with SYLVANT requires ongoing monitoring of blood counts (complete blood count), liver function tests, lipid panels (triglycerides and cholesterol), and renal function. Your doctor will schedule regular blood tests to ensure that any laboratory abnormalities are detected and managed early.
If you experience any side effects, including those not listed here, tell your doctor or nurse. You can also report suspected side effects to your national pharmacovigilance authority (e.g., the EMA in Europe, the FDA MedWatch program in the United States, or the MHRA Yellow Card Scheme in the United Kingdom). Reporting helps monitor the ongoing benefit-risk profile of SYLVANT and contributes to drug safety for all patients.
How Should SYLVANT Be Stored?
Keep this medicine out of the sight and reach of children. Do not use after the expiry date stated on the vial label and outer carton after EXP. The expiry date refers to the last day of that month.
- Unopened vials: Store in a refrigerator at 2°C to 8°C (36°F to 46°F). Do not freeze.
- Light protection: Keep the vial in the original carton to protect from light.
- Reconstituted solution: Should not be stored for more than 2 hours before being added to the infusion bag.
- Diluted infusion: The infusion must be completed within 6 hours of adding the reconstituted solution to the infusion bag.
- Inspection: Do not use if the solution appears cloudy, contains foreign particles, or is discolored after reconstitution.
As SYLVANT is prepared and administered in a hospital or clinic, storage will be handled by your healthcare team and pharmacy. SYLVANT does not contain preservatives, so do not save any unused infusion solution for later use. The doctor or nurse will ensure proper disposal of unused medicine and waste materials in accordance with local requirements.
What Does SYLVANT Contain?
Active Substance
The active substance is siltuximab. Siltuximab is a chimeric (human-murine) monoclonal antibody produced in Chinese Hamster Ovary (CHO) cells by recombinant DNA technology. Each single-use glass vial contains 100 mg of siltuximab as a white lyophilized powder. After reconstitution with 5.2 mL of sterile water for injection, the resulting solution contains 20 mg of siltuximab per mL.
Inactive Ingredients (Excipients)
- Histidine
- Histidine hydrochloride monohydrate
- Polysorbate 80
- Sucrose
Appearance
SYLVANT is supplied as glass vials containing a white lyophilized powder (powder for concentrate for solution for infusion). After reconstitution with water for injection, the solution should be clear and colorless to slightly yellow. Each package contains one single-use vial.
Marketing Authorization Holder and Manufacturer
The marketing authorization holder is Recordati Netherlands B.V., Beechavenue 54, 1119PW Schiphol-Rijk, Netherlands. SYLVANT is manufactured by Janssen Biologics B.V., Einsteinweg 101, NL-2333 CB Leiden, Netherlands. Further information about SYLVANT is available from the European Medicines Agency (EMA) website and the FDA drug database.
Frequently Asked Questions About SYLVANT
SYLVANT (siltuximab) is used to treat multicentric Castleman disease (MCD) in adult patients who are HIV-negative and HHV-8-negative. MCD is a rare disorder involving the overgrowth of cells in lymph nodes throughout the body, driven by excessive production of interleukin-6 (IL-6). SYLVANT is the first and only drug specifically approved for this indication and works by blocking IL-6 to reduce lymph node enlargement, relieve symptoms, and normalize inflammatory markers.
SYLVANT is given as an intravenous (IV) infusion over approximately 1 hour, once every 3 weeks (every 21 days). Each dose is 11 mg per kilogram of body weight. Treatment continues for as long as the patient derives clinical benefit, which can be months or years. You will receive each infusion in a hospital or clinic under the supervision of healthcare professionals.
No, SYLVANT is only approved for HHV-8-negative, HIV-negative multicentric Castleman disease. In HHV-8-positive MCD, the virus produces its own version of IL-6 (viral IL-6 or vIL-6) that is structurally different from human IL-6 and is not blocked by siltuximab. Therefore, SYLVANT would not be effective in this setting. HHV-8-positive MCD requires different treatment approaches, often including rituximab-based regimens or antiviral therapy.
SYLVANT blocks interleukin-6, which is a key mediator of the body’s inflammatory response. IL-6 plays a central role in triggering fever, stimulating the production of acute-phase proteins like C-reactive protein (CRP), and activating the immune system. When IL-6 is neutralized by SYLVANT, these normal inflammatory responses are suppressed. This means you may not develop a fever or have elevated CRP levels even when a serious infection is present. It is therefore crucial to report any symptoms of infection to your doctor, regardless of whether you have a fever.
In the pivotal randomized, double-blind, placebo-controlled clinical trial (MCD3001), SYLVANT demonstrated a durable tumor and symptomatic response rate of 34% compared to 0% in the placebo group. The median time to treatment failure was not reached in the SYLVANT group compared to 134 days in the placebo group. Additionally, 18 of 19 responders (95%) maintained their response for at least 18 months. SYLVANT also significantly improved hemoglobin levels, reduced CRP, and relieved disease-related symptoms. Long-term follow-up data has shown that many patients continue to benefit from treatment for years.
SYLVANT is not recommended during pregnancy because its safety for unborn babies has not been established. Women of childbearing potential should use effective contraception during treatment and for at least 3 months after the last dose. In some cases, if a pregnant woman requires treatment for MCD, the doctor may decide that the benefit to the mother outweighs the potential risks. This decision should be made on a case-by-case basis with careful consideration of both maternal health and the potential for increased infection risk and vaccine restrictions in the infant.
References
- European Medicines Agency (EMA). SYLVANT (siltuximab) – Summary of Product Characteristics. Last updated 2025. Available from: EMA EPAR.
- U.S. Food and Drug Administration (FDA). SYLVANT (siltuximab) Prescribing Information. Revised 2024. Available from: FDA Drug Label.
- van Rhee F, Wong RS, Munshi N, et al. Siltuximab for multicentric Castleman’s disease: a randomised, double-blind, placebo-controlled trial. Lancet Oncol. 2014;15(9):966–974. doi:10.1016/S1470-2045(14)70319-5.
- van Rhee F, Voorhees P, Dispenzieri A, et al. International, evidence-based consensus treatment guidelines for idiopathic multicentric Castleman disease. Blood. 2018;132(20):2115–2124. doi:10.1182/blood-2018-07-862334.
- Fajgenbaum DC, Uldrick TS, Bagg A, et al. International, evidence-based consensus diagnostic criteria for HHV-8-negative/idiopathic multicentric Castleman disease. Blood. 2017;129(12):1646–1657. doi:10.1182/blood-2016-10-746933.
- van Rhee F, Casper C, Voorhees PM, et al. Long-term safety of siltuximab in patients with idiopathic multicentric Castleman disease: a prespecified, open-label, extension analysis of two trials. Lancet Haematol. 2020;7(3):e209–e217. doi:10.1016/S2352-3026(19)30257-1.
- Dispenzieri A, Fajgenbaum DC. Overview of Castleman disease. Blood. 2020;135(16):1353–1364. doi:10.1182/blood.2019000931.
- National Comprehensive Cancer Network (NCCN). NCCN Clinical Practice Guidelines in Oncology: T-Cell Lymphomas (including Castleman Disease). Version 1.2025.
- Castleman Disease Collaborative Network (CDCN). CDCN Evidence-Based Consensus Treatment Guidelines for Idiopathic Multicentric Castleman Disease. Updated 2024.
- World Health Organization (WHO). WHO Model List of Essential Medicines – 23rd List. Geneva: WHO; 2023.
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