Background Intravenous immunoglobulin (IVIg) use has increased due to its therapeutic effects in numerous diseases. Despite this, IVIg label indications remain limited.

Purpose To assess the use of IVIg in hospitalised patients and outpatients in a tertiary hospital in terms of:

1. adequacy of use to label indications; and

2. economic impact on the conditions used (label and off-label indications).

Material and methods Retrospective study from January 2014 to December 2014. Collected data, obtained from Farmatools software and medical records, were: sex, age, IVIg indication, dose and number of administrations to each patient, and treatment costs. A descriptive analysis of IVIg use per patient and indication and associated cost was made. IVIg adequacy of use was established based on the British Clinical guidelines for Immunoglobulin Use, 2nd edition, July 2011 update.

Results 138 patients (average age 59.1, 58.7% female) received IVIg. 44.1% of treatments were administered to hospitalised patients.

Label indications were 67.4%: common variable immunodeficiency (55/93), IgG immunodeficiency (13/93), idiopathic thrombocytopenic purpura (12/93), Guillain-Barré syndrome (6/93), Kawasaki disease (3/93), secondary immunodeficiency (2/93), hyperIgM immunodeficiency (1/93) and unspecified hypogammaglobulinaemia (1/93).

Off-label indications supported by clinical evidence were 21.0%: myasthenia gravis (7/29), multifocal motor neuropathy (6/29), non-specific demyelinating neuropathy (4/29), chronic inflammatory demyelinating polyradiculoneuropathy (3/29), inclusion body myositis (3/29), autoimmune haemolytic anaemia (2/29), polymyositis (1/29), dermatomyositis (1/29), Rassmusen syndrome (1/29) and alloimmune thrombocytopenia (1/29).

Off-label indications not sufficiently supported by clinical evidence were 5.8%: systemic vasculitits (2/8), scleroderma (2/8), polyarteritis nodosa (2/8), microscopic polyarteritis (1/8), acute disseminated encephalomyelitis (1/8).

Non-recommended indications were 5.8%: systemic lupus erythematosus (3/8), epilepsy (2/8), proximal diabetic neuropathy (1/8), aplastic anaemia (1/8) and paraneoplastic syndrome (1/8).

For each category, IVIg dispensed were 22 252.5 g, 16 632.5 g, 7287.5 g and 5247.5 g, respectively. Percentage expenditure for each one was 41.4%, 34.2%, 13.9% and 10.5%, respectively (of a total amount of 1 730 002€).

Conclusion Despite the fact that most of the dispensed IVIg were used for label or for off-label supported by clinical evidence indications, uses with unproven clinical benefit, even those recommended, implies an important expense in our hospital. Due to the frequent off-label use of IVIg, implementing a protocol would be useful to adjust IVIg treatments to the guideline recommendations and to optimise its use.

No conflict of interest.