Etanercept (Enbrel, Wyeth Pharmaceuticals) is a human tumour necrosis factor (TNF) receptor fusion protein that inhibits TNF-alpha binding to cell surface TNF receptors. Etanercept is licensed for the treatment of active and progressive psoriatic arthritis in adults whose disease has not responded adequately to previous disease-modifying antirheumatic drug (DMARD) therapy.
The most common adverse events reported in the trials were infections (including upper respiratory tract infections, bronchitis, cystitis and skin infections), injection site reactions (including bleeding, bruising, erythema, itching, pain and swelling), and allergic reactions, such as pruritus. For full details of undesirable effects and contraindications, see the summary of product characteristics.
The acquisition cost of etanercept is £89.38 per 25-mg prefilled syringe or 25-mg vial with powder for reconstitution (with solvent), and £178.75 per 50-mg prefilled syringe (excluding VAT; BNF edition 58). The annual cost of etanercept using either 50-mg once-weekly doses (52 doses per year) or 25‑mg twice-weekly doses (104 doses per year) is £9,295. Costs may vary in different settings because of negotiated procurement discounts.
Infliximab (Remicade, Schering-Plough) is a chimeric human-murine monoclonal antibody that inhibits the functional activity of TNF-alpha. Infliximab is licensed for the treatment of active and progressive psoriatic arthritis in adults when the disease has not responded adequately to previous DMARD therapy. Infliximab should be administered:
in combination with methotrexate or
alone in people who show intolerance to methotrexate or for whom methotrexate is contraindicated.
The most common reported adverse events in the trials were infusion reactions and hypersensitivity, infections (tuberculosis, bacterial infections – including sepsis and pneumonia – invasive fungal infections, and other opportunistic infections), hepatitis B reactivation and heart failure. For full details of undesirable effects and contraindications, see the summary of product characteristics.
The acquisition cost of infliximab is £419.62 per 100-mg vial with powder for reconstitution (excluding VAT; BNF edition 58). The drug cost differs between individuals because the dose is adjusted to each person's body weight. For example, for an adult weighing 75 kg, if it is assumed that vials are not shared between patients, each infusion of 5 mg/kg requires 4 × 100-mg vials at a cost of £1,678. The 3 initial infusions are given at weeks 0, 2 and 6, at a cost of £5,035. The subsequent annual cost following the loading doses is £10,910 per year based on infusions repeated every 8 weeks (average 6.5 doses per year). Costs may vary in different settings because of negotiated procurement discounts.
Adalimumab (Humira, Abbott Laboratories) is a recombinant human monoclonal antibody that binds specifically to TNF and neutralises its function. Adalimumab is licensed for the treatment of active and progressive psoriatic arthritis in adults when the disease has not responded adequately to previous DMARD therapy.
The most common reported adverse events in the trials were infections (including sepsis due to bacterial, mycobacterial, invasive fungal, parasitic, viral, or other opportunistic infections such as listeriosis and pneumocystis), tuberculosis, hepatitis B reactivation, formation of autoimmune antibodies and congestive heart failure. For full details of undesirable effects and contraindications, see the summary of product characteristics.
The acquisition cost of adalimumab is £357.50 per 40-mg prefilled pen or prefilled syringe (excluding VAT; BNF edition 58). The annual acquisition cost of adalimumab to the NHS is £9,295 per patient (based on 26 injections per year). Costs may vary in different settings because of negotiated procurement discounts.