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Active Substance: siltuximab
Common Name: siltuximab
ATC Code: L04AC11
Marketing Authorisation Holder: Janssen-Cilag International NV
Active Substance: siltuximab
Status: Authorised
Authorisation Date: 2014-05-22
Therapeutic Area: Giant Lymph Node Hyperplasia
Pharmacotherapeutic Group: Immunosuppresants, interleukin inhibitors

Therapeutic Indication

Sylvant is indicated for the treatment of adult patients with multicentric Castleman’s disease (MCD who are human immunodeficiency virus (HIV) negative and human herpesvirus-8 (HHV-8) negative.

What is Sylvant and what is it used for?

Sylvant is a medicine that contains the active substance siltuximab. It is used to treat multicentric Castleman’s disease in adults who tested negative for the human immunodeficiency virus (HIV) and the human herpesvirus-8 (HHV-8).

Castleman’s disease is a disorder of the lymphatic system (a network of vessels that transport fluid from tissues through the lymph nodes and into the bloodstream) in which cells in lymph nodes start growing abnormally, causing benign tumours. Multicentric means that the disease affects several lymph nodes as well as other organs in the body. Symptoms can include tiredness, sweating at night, fever, peripheral neuropathy (pins and needles due to nerve damage) and enlargement of liver and spleen.

Because the number of patients with Castleman’s disease is low, the disease is considered ‘rare’, and Sylvant was designated an ‘orphan medicine’ (a medicine used in rare diseases) on 30 November 2007.

How is Sylvant used?

Sylvant can only be obtained with a prescription and treatment should be given by qualified healthcare professionals and under appropriate medical supervision. Sylvant is available as a powder to be made into a solution for infusion (drip) into a vein. The recommended dose is 11 mg per kilogram body weight, and the infusion should last around one hour. Sylvant is given every three weeks, until the patient no longer benefits from treatment.

During the first 12 months of treatment blood tests should be performed before each dose of Sylvant, and every nine weeks afterwards; treatment may need to be delayed in patients whose blood tests are abnormal or who have certain side effects. For further information, see the summary of product characteristics.

How does Sylvant work?

The active substance in Sylvant, siltuximab, is a monoclonal antibody. A monoclonal antibody is an antibody (a type of protein) that has been designed to recognise and attach to a specific structure (called an antigen) that is found in the body. Siltuximab has been designed to attach to and block the activity of a protein in the body called interleukin 6 (IL-6). Patients with the disease produce too much IL-6 and this is thought to contribute to the abnormal growth of certain cells in the lymph nodes. By attaching to IL-6, siltuximab blocks its activity and stops abnormal cell growth, thus reducing the size of the lymph nodes and the symptoms of the disease.

Sylvant is produced by a method known as ‘recombinant DNA technology’; it is made by cells that have received a gene (DNA), which makes them able to produce siltuximab.

What benefits of Sylvant have been shown in studies?

Sylvant has been investigated in one main study involving 79 adults with multicentric Castleman’s disease who tested negative for HIV and HHV-8. The effect of the medicine was compared with placebo (a dummy treatment) and the main measure of effectiveness was the proportion of patients who responded to treatment for at least 18 weeks, as shown by a 50% reduction (‘partial response’) or complete disappearance (‘complete response’) of tumours and symptoms of the disease.

Sylvant was more effective than placebo in reducing tumour size and disease symptoms: 17 out of 53 patients who received Sylvant showed a partial response and one showed a complete response, compared with none of the 26 patients who received placebo. This effect was maintained for almost one year.

What are the risks associated with Sylvant?

The most common side effects with Sylvant (seen in more than 2 in 10 people) are infections (including upper respiratory tract infections (colds)), pruritus (itching), and rash. The most serious side effect is anaphylactic reaction (a severe allergic reaction).

For the full list of side effects and restrictions, see the package leaflet.

Why is Sylvant approved?

The Agency’s Committee for Medicinal Products for Human Use (CHMP) decided that Sylvant’s benefits are greater than its risks and recommended that it be approved for use in the EU. The CHMP concluded that Sylvant has been shown to have a beneficial effect by reducing tumour size and symptoms in patients with multicentric Castleman’s disease, and that this positive effect seems to be maintained over time. The Committee also acknowledged that there is an unmet medical need for these patients. Regarding its safety, side effects with Sylvant were considered to be acceptable but further long-term data are to be collected.

What measures are being taken to ensure the safe and effective use of Sylvant?

A risk management plan has been developed to ensure that Sylvant is used as safely as possible. Based on this plan, safety information has been included in the summary of product characteristics and the package leaflet for Sylvant, including the appropriate precautions to be followed by healthcare professionals and patients.

Additionally, the company that markets Sylvant is required to set up a patient registry to provide further data on long-term safety. The company will ensure that healthcare professionals who are expected to use the medicine are provided with information on how to enter their patients in the registry.

Further information can be found in the summary of the risk management plan.

Other information about Sylvant

The European Commission granted a marketing authorisation valid throughout the European Union for Sylvant on 22 May 2014.

For more information about treatment with Sylvant, read the package leaflet (also part of the EPAR) or contact your doctor or pharmacist.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.