Etanercept (Enbrel®, Erelzi®, Benepali®): everything there is to know about this drug!

What is tanercept? When is it prescribed? 

Etanercept belongs to a class of medicines known as biological response modifiers or tumour necrosis factor inhibitors (anti-TNFα). These drugs require a doctor's prescription, and their dispensing is subject to strict rules, due to their high cost and their therapeutic indications, which must be scrupulously respected.

Etanercept is a biotherapy - a medical treatment that uses biological substances, such as antibodies or proteins, to specifically target certain diseases or disorders. The best-known molecules are adalimumab, etanercept and infliximab.

These drugs reduce the inflammatory reaction present in certain chronic conditions, by blocking the action of TNF.

Etanercept is a soluble receptor that binds to TNFα and prevents it from attaching to target cells, blocking the development of skin inflammation. Etanercept-based drugs include Enbrel®, Erelzi® and Benepali®.

Etanercept is used in the treatment of the following diseases:

• Rheumatoid arthritis,
  
• Plaque psoriasis,
  
• Ankylosing spondylitis,
  
• Axial spondyloarthritis,
  
• Psoriatic arthritis,
  
• Juvenile idiopathic arthritis.
  

This treatment is effective not only on the skin, but also on the joints. The time it takes for the medication to start being effective varies from one patient to another, but the first results can generally be seen within the first two weeks of administration. Although it may take 3 to 6 months for the full effect of the drug to be felt.

Etanercept doses should be kept refrigerated at between +2°C and +8°C, and the drug should be removed from the fridge at least 30 minutes before administration. It may also be stored at room temperature not exceeding 25°C for a maximum of 4 weeks. During this period, it must not be put back into the refrigerator.

How is etanercept administered? What are some precautions you should take? 

Treatment with etanercept should be initiated and monitored by a specialist experienced in the diagnosis and treatment of the above mentioned chronic diseases. Clinical monitoring of the patient is carried out before, during and after treatment.

In order to improve the traceability of biological medicines, the brand name and batch number of the product administered must be clearly recorded in the patient's file.

The medicine is injected subcutaneously via a pre-filled disposable syringe or a pre-filled single-use auto-injector into the arms, but also into the thighs or the abdomen. The frequency of injections depends on the dosage. It is usually between 1 (50mg) and 2 (25mg) subcutaneous injections per week for the first three months, then 1 (50mg) injection per week as maintenance treatment. Injections can be given by the patient themselves, and the injection site should be different each time.

The dosage will depend on the patient's age and their disease, but not necessarily on their weight. However, maximum doses must not be exceeded and treatment duration must be carefully respected.

Treatment lasts 6 months. If necessary, it can be prescribed for a further 6 months, or administered continuously for several years. Treatment may be stopped if there is no response, usually after 3/4 months.

Etanercept should not be prescribed in cases of progressive infection, if the patient has recently been treated for cancer (less than 5 years), if the patient or a member of the patient's family is affected by multiple sclerosis, or if the patient has severe heart failure.

This treatment is an immunosuppressant, so there are a number of precautions to be taken:

• Consult your doctor in the event of haematological disorders: for example, if you have abnormal blood work (abnormal red or white blood cells count, platelets count, haemoglobin or iron level, etc),
  
• Consult your doctor if you have signs of tuberculosis: persistent fever, night sweats, chronic cough with thick sputum and sometimes trickles of blood, shortness of breath, chest pain, loss of appetite, weight loss, etc.
  
• Consult your doctor if you notice any symptoms of infection,
  
• Use contraception throughout treatment and for 3 weeks afterwards. Pregnancy is possible but questionable depending on the severity of the disease and in the absence of other available therapeutic options,
  
• If you are breast-feeding, you should stop doing it for the duration of treatment,
  
• Discontinue treatment in the event of a severe hypersensitivity to the active substance or reactivation of hepatitis B.

Like most medicines, etanercept carries the risk of drug interactions. Live attenuated virus vaccines (BCG, chickenpox, yellow fever), for example, are not recommended if you are taking etanercept.

These risks of drug interactions range from critical (the use is contraindicated) to moderate (the use is not recommended or should be done with caution).

What are the most common side effects from taking etanercept? 

As any drug of this type, etanercept carries the risk of side effects, which must be carefully watched for and rapidly taken care of. Most of the side effects improve with time and are reversible.

However, you should bear in mind that this treatment reduces the activity of the immune system. It is therefore essential to see a doctor in the event of any infection or abnormal symptoms. What's more, if for any other medical reason surgery is required, treatment should be discontinued.

The most common short-term side effect is skin reaction at the injection site, which may include redness, swelling or itching. The treatment may also cause headaches.

In rare cases, the following symptoms may occur and if they do, it requires medical attention:

• Skin rashes,
  
• Damage to the nervous system such as muscle weakness, tingling in the extremities, etc. (e.g. multiple sclerosis),
  
• Worsening of heart failure in people already suffering from heart disease,
  
• Infections, especially of the upper respiratory tract, but also of the skin, and other organs (cystitis, etc),
  
• Epileptic seizures.
  

If you have any questions about the compatibility of etanercept with your usual activities, such as dental treatment, surgery or even holidays abroad, you should discuss them with your doctor.

All doctors, other than the prescribing doctor, must be informed that you are being treated by etanercept.