Etanercept and efalizumab for the treatment of adults with psoriasis

Etanercept (Wyeth Pharmaceuticals) is a recombinant human tumour necrosis factor (TNF) receptor fusion protein that inhibits the activity of TNF. TNF is a cytokine that is released from T lymphocytes; it mediates inflammation and modulates the cellular immune response. Etanercept is licensed for the 'treatment of adults with moderate to severe plaque psoriasis who have failed to respond to, or who have a contraindication to, or who are intolerant to other systemic therapies including ciclosporin, methotrexate or PUVA'. It is also licensed for the treatment of active and progressive PsA in adults when the response to previous disease-modifying anti-rheumatic drug (DMARD) therapy has been inadequate.

The summary of product characteristics (SPC) specifies that etanercept treatment should be initiated and supervised by specialist physicians with experience in the diagnosis and treatment of psoriasis. The SPC also states that the use of etanercept in combination with other systemic therapies or phototherapies has not been studied.

The most frequent adverse events reported during etanercept therapy include injection site reactions, infections and allergic reactions. The SPC specifies a number of uncommon but serious adverse events that may be related to the immunomodulatory activity. There are no monitoring requirements. For full details of side effects and contraindications, see the SPC.

Etanercept is administered by subcutaneous injection at a dose of 25 mg twice weekly. Alternatively, 50 mg given twice weekly may be used for up to 12 weeks followed, if necessary, by a dose of 25 mg twice weekly. The SPC states that treatment with etanercept should continue until remission is achieved, for up to 24 weeks. Treatment should be discontinued in patients who show no response after 12 weeks. If re-treatment with etanercept is indicated, the above guidance on treatment duration should be followed. The net price for a 25 mg vial is £89.38 (excluding VAT; BNF 49th edition). Costs may vary in different settings because of negotiated procurement discounts.

Efalizumab (Serono Pharmaceuticals Ltd) is a T-cell modulator that blocks T-cell activation or migration. It is licensed for the 'treatment of adults with moderate to severe plaque psoriasis who have failed to respond to, or who have a contraindication to, or who are intolerant to other systemic therapies including ciclosporin, methotrexate and PUVA'. The UK marketing authorisation for efalizumab also specifies that the psoriasis should be chronic, and it is contraindicated in patients with specific forms of psoriasis like guttate, erythrodermic or pustular psoriasis as the sole or predominant form.

The SPC states that efalizumab treatment should be initiated by a physician specialised in dermatology. The SPC states that efalizumab has not been studied in combination with immunosuppressive systemic anti-psoriasis medicinal products and therefore combination therapy with these products is not recommended. The SPC also states that 'combination therapy with topical corticosteroids is not associated either with any untoward effects or with any observable significant benefit above monotherapy'.

The most frequent adverse drug reactions reported during efalizumab therapy are mild to moderate dose-related acute flu-like symptoms (associated with the first few doses), leucocytosis and lymphocytosis. Owing to the risk of thrombocytopenia, monthly platelet counts are recommended on initiation of therapy, but the frequency can be decreased to every 3 months with continued treatment. For full details of side effects and contraindications, see the SPC.

Efalizumab is administered at an initial single dose of 0.7 mg/kg body weight followed by weekly subcutaneous injections of 1.0 mg/kg body weight (maximum single dose should not exceed a total of 200 mg). The SPC states that the duration of therapy is 12 weeks and may only be continued in patients who respond to treatment. The net price for a 125 mg vial is £169.20 (excluding VAT; BNF, 49th edition). Costs may vary in different settings because of negotiated procurement discounts.