• Keep this leaflet. You may need to read it again.
• If you have any further questions, ask your doctor.
• If you get any side effects, talk to your doctor. This includes any possible side effects not listed in this leaflet. See section 4.

1. What Idefirix is and what it is used for
2. What you need to know before you are given Idefirix
3. How to use Idefirix
4. Possible side effects
5. How to store Idefirix
6. Contents of the pack and other information

• If you are allergic to imlifidase or any of the other ingredients of this medicine (listed in section 6).
• If you have a severe infection.
• If you have a blood disorder called thrombotic thrombocytopenic purpura (TTP), that results in blood clots forming in small blood vessels throughout the body.

Infusion reactions

Idefirix contains a protein and it can cause allergic reactions in some people. You will receive medicines to reduce the risk of an allergic reaction. If you get any symptoms of an allergic reaction, such as severe rash, shortness of breath, feeling hot, flushing, during the infusion (‘drip’), the infusion may need to be slowed down or stopped. When these symptoms go away, or improve, the infusion can be continued.

Infections

IgG is important for protecting you against infections and since Idefirix breaks down IgG, you will receive antibiotics to reduce the risk of infections.

Antibody-mediated rejection (AMR)

Your body will produce new IgG antibodies, which may attack the transplanted kidney. Your doctor will monitor you closely and you will receive medicines to reduce the risk of rejection.

Do not give this medicine to children and adolescents under 18 years of age because it has not been studied in this age group.

Tell your doctor if you are using, have recently used or might use any other medicines. Idefirix can affect the way some medicines work, and the dose of these may have to be adjusted.

As Idefirix breaks down IgG, IgG-based medicines may not work if given at the same time as Idefirix. This includes the following medicines:

• basiliximab (used to prevent rejection of kidney transplants)
• rituximab (used to treat cancers such as non-Hodgkin’s lymphoma and chronic lymphocytic leukaemia and inflammatory diseases such as rheumatoid arthritis)
• alemtuzumab (used to treat a form of multiple sclerosis)
• adalimumab (used to treat inflammatory diseases such as rheumatoid arthritis, ankylosing spondylitis, psoriasis, Crohn’s disease and ulcerative colitis)
• denosumab (used to treat osteoporosis)
• belatacept (used to prevent rejection of kidney transplants)
• etanercept (used to treat inflammatory diseases such as rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis and psoriasis)
• rabbit anti-thymocyte globulin (rATG) (used to prevent rejection of kidney transplants)
• intravenous immunoglobulin (IVIg) (used to increase abnormally low immunoglobulin levels in the blood or to treat inflammatory diseases such as Guillain-Barré syndrome, Kawasaki disease and chronic inflammatory demyelinating polyneuropathy).

Idefirix is not recommended during pregnancy.

Talk to your doctor if you think you may be pregnant.

It is not known whether Idefirix passes into breast milk. You should not breast-feed if you are being treated with Idefirix.

This medicine contains less than 1 mmol sodium (23 mg) per dose, that is to say essentially ′sodium-free′.

During and after the infusion you will be closely monitored. Healthcare professionals will check for any side effects.

• Signs of infection, such as fever, chills, cough, feeling weak or generally unwell (very common - may affect more than 1 in 10 people).
• Signs of an infusion reaction, such as severe rash, shortness of breath, feeling hot, flushing (common - may affect up to 1 in 10 people).
• Muscle pain or fatigue (symptoms of myalgia) (common - may affect up to 1 in 10 people).

If you get any side effects, talk to your doctor. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme. Website: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store. By reporting side effects, you can help provide more information on the safety of this medicine.

• The active substance is imlifidase. Each vial contains 11 mg imlifidase. After reconstitution, each mL of concentrate contains 10 mg imlifidase.
• The other ingredients are mannitol, polysorbate 80, trometamol, disodium edetate dihydrate and hydrochloric acid (for pH adjustment). See section 2 “Idefirix contains sodium”.

• Idefirix is supplied as a glass vial containing a powder for concentrate for solution for infusion (powder for concentrate). The powder is a white freeze-dried cake.
• Packs contain 1 or 2 vials.