SYLVANT results

The effectiveness of SYLVANT® (siltuximab) has been proven in the only randomized clinical trial in patients with idiopathic multicentric Castleman disease (iMCD). The primary treatment goals of the trial were reduction in lymph node size and improvement in symptoms. According to the trial criteria, these improvements must last for at least 18 weeks without treatment failure.

Low hemoglobin levels have been observed in patients with iMCD, which can make them anemic. The secondary treatment goal was to help improve hemoglobin levels.

None of the patients on placebo achieved the primary or the secondary treatment goals.

letter icon

0% of patients receiving SYLVANT achieved the primary treatment goals vs 0% of patients on placebo.

letter icon

0% of patients showed improvement in their hemoglobin levels.

The SYLVANT clinical trial referenced above took place before the diagnostic guidelines for iMCD were available.

Application of diagnostic guidelines showed a greater response to SYLVANT

The diagnostic guidelines for iMCD consist of several criteria that are used by doctors to diagnose patients faster. The minor diagnostic criteria include symptoms such as enlarged liver, enlarged spleen, fever, fatigue, and fluid accumulation.

In the clinical trial, SYLVANT was studied for 48 weeks after the last patient began treatment, which was approximately 3 years of follow-up. Once the guidelines were applied to the data from the clinical trial (mentioned above), it was found that there was significant improvement when ≥2 minor criteria were met.

Significant Improvement When at Least 2 Minor Criteria Are Met

At least 4 (n=22) At least 3 (n=28) At least 2 (n=35) 60% 50% 40% 30% 20% 10% 0% None (n=16) 55% 46% 43% 0% Patients 34% previously achieving the primary end point Number of Minor Criteria Met
Graph showing the efficacy of SYLVANT (siltuximab) in people with idiopathic multicentric Castleman disease.

The NCCN recommends siltuximab (SYLVANT) as the preferred primary treatment for iMCD

The CDCN also recommends the frontline use of SYLVANT in treating iMCD

Using Fisher’s exact test, patients who met at least 2 minor criteria were significantly more likely to respond to SYLVANT than those who did not (P = .0003).
Abbreviations: CDCN, Castleman Disease Comprehensive Network; NCCN, National Comprehensive Cancer Institute®.

improvement icon

After starting SYLVANT, patients may start to see some symptom improvement within the first few weeks, but it may take between 4 and 9 months for lymph nodes to shrink. That’s why it is important for patients to stay on SYLVANT.

Carl, iMCD patient testimonial Sylvant

After I started treatment with SYLVANT, my symptoms started to decrease. I was getting my appetite back and the night sweats decreased.

– Carl, iMCD patient

letter icon

Need more information?

Sign up to receive emails about iMCD, SYLVANT, lifestyle tips, patient stores, and more.

eye icon

Insights on iMCD

Are you an iMCD patient or caregiver?*
Have you been prescribed SYLVANT® (siltuximab) for the treatment of iMCD?*
See More

Important Safety Information

What is SYLVANT?

SYLVANT® (siltuximab) is a prescription medicine used to treat people with multicentric Castleman’s disease (MCD) who do not have human immunodeficiency virus (HIV) and human herpesvirus-8 (HHV-8) infection. It is not known if SYLVANT is safe and effective in children.

Important Safety Information

What is SYLVANT?

SYLVANT® (siltuximab) is a prescription medicine used to treat people with multicentric Castleman’s disease (MCD) who do not have human immunodeficiency virus (HIV) and human herpesvirus-8 (HHV-8) infection. It is not known if SYLVANT is safe and effective in children.

Who should not take SYLVANT?

Do not take SYLVANT if you have had a severe allergic reaction to siltuximab or any of the ingredients in SYLVANT. See the Patient Information for a complete list of ingredients in SYLVANT.

What are the possible side effects of SYLVANT?

SYLVANT may cause serious side effects, including:

Infections. SYLVANT may lower your ability to fight infections. Tell your healthcare provider right away if you have any signs or symptoms of an infection during treatment with SYLVANT.

Infusion and allergic reactions. If you have an infusion or allergic reaction while receiving SYLVANT, your healthcare provider will stop your infusion and treat your reaction. If you have a severe infusion or allergic reaction, your healthcare provider may stop your treatment completely. Tell your healthcare provider or get medical help right away if you have any of these symptoms during or after your infusion of SYLVANT:

  • back pain
  • chest pain or tightness
  • nausea and vomiting
  • flushing
  • redness
  • irregular heart beat (palpitations)
  • trouble breathing
  • wheezing
  • dizziness or light-headedness
  • swelling of the lips
  • skin rash
  • headache
  • itching

The most common side effects of SYLVANT include:

rash, itching, upper respiratory tract infection, swelling, weight gain, and increased blood level of uric acid.

These are not all the possible side effects of SYLVANT. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Before you take SYLVANT, tell your healthcare provider about all of your medical conditions, including if you:

  • have an infection. You should not take SYLVANT if you have a severe infection.
  • have had a recent vaccination or are scheduled to receive any vaccinations. You should not receive a live vaccine during your treatment with SYLVANT.
  • have or have had any stomach or bowel (intestine) problems, such as diverticulitis or ulcers. Tell your healthcare provider if you have any pain or discomfort in your stomach.
  • are pregnant or plan to become pregnant. It is not known if SYLVANT will harm your unborn baby. You should not become pregnant while receiving treatment with SYLVANT. Females who are able to become pregnant should use effective birth control during treatment with SYLVANT and for 3 months after stopping treatment.
  • are breastfeeding or plan to breastfeed. It is not known if SYLVANT passes into your breast milk. You and your healthcare provider should decide if you will take SYLVANT or breastfeed. You should not do both.

Tell your healthcare provider about all the medicines you take,

including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Please see full Prescribing Information for additional Important Safety Information.