2 The technology
2.1 Adalimumab (Humira, AbbVie) is an antibody that inhibits tumour necrosis factor (TNF). It is given by subcutaneous injection. Adalimumab has a marketing authorisation in the UK for treating active moderate to severe hidradenitis suppurativa (acne inversa) in adult patients with an inadequate response to conventional systemic hidradenitis suppurativa therapy. The summary of product characteristics suggests that 'continued therapy beyond 12 weeks should be carefully reconsidered in a patient with no improvement within this time period'. This statement is clarified in the European Public Assessment Report (EPAR), which states that continued benefit of adalimumab was observed in anyone with a partial response or higher, defined as at least a 25% reduction in abscess and inflammatory nodule (AN) count with or without an increase in abscesses or draining fistulas from baseline. The summary of product characteristics also recommends that the benefit and risk of continued long‑term treatment should be evaluated periodically.
2.2 The summary of product characteristics lists the following very common (affecting 1 in 10 people or more) adverse reactions for adalimumab: respiratory tract infections; low white blood cell count; low red blood cell count; increased blood lipids; headache; abdominal pain; nausea and vomiting; rash; musculoskeletal pain; injection site reactions; and increased plasma levels of liver enzymes. For full details of adverse reactions and contraindications, see the summary of product characteristics.
2.3 Adalimumab costs £352.14 for a 40‑mg prefilled pen or syringe and for a 40‑mg/0.8‑ml vial (British national formulary; accessed December 2015). The recommended dose of adalimumab for people with hidradenitis suppurativa is 160 mg on day 1 (given as 4 injections in 1 day or as 2 injections each day for 2 consecutive days), 80 mg on day 15 (given as 2 injections in 1 day), and a single 40‑mg injection every week from week 4 onwards. Antibiotics may be continued during treatment with adalimumab, if necessary. The company has agreed a patient access scheme with the Department of Health. The company will provide adalimumab at a fixed price of £284.00 for the 40‑mg prefilled pen or syringe for the hidradenitis suppurativa indication only. The Department of Health considered that this patient access scheme does not constitute an excessive administrative burden on the NHS. The annual cost of treatment with adalimumab is estimated at £15,336, based on the dosing regimen recommended in the summary of product characteristics.