An analysis of the teaching of intravenous self-administration in patients with hereditary angio-oedema

Background. Hereditary angio-oedema (HAE), C1 inhibitor HAE (C1-INH-HAE) type I and C1-INH-HAE type II, are inherited disorders characterised by potentially life-threatening recurrent swellings, caused by a deficiency of C1 inhibitor. Management includes attack treatment or prevention using prophylaxis/routine prevention. Aim. To evaluate the success of self-administration training as part of a home care programme for treatment of HAE using intravenous C1 inhibitor. Methods. In total, 18 patients (7 men, 11 women; aged 18-72 years) were trained to self-administer a plasma-derived C1 inhibitor concentrate for acute treatment or routine prevention of HAE attacks. The number of training sessions needed to learn intravenous self-administration, delay in time to treatment and reduction in attack frequency (per month) were evaluated after completion of the training. Results. All patients successfully completed training. The median number of training sessions required to be capable of unassisted/independent self-injection was 5 (range 2-30). Time to treatment was reduced from a median of 4.5 h (270 min) by medical professionals to 15 min by patients after self-administration training). Using the treatment as routine prevention resulted in a reduction of median frequency of attacks from 8 to 0.5 attacks/month. Conclusion. C1 inhibitor self-administration for the treatment of HAE allows patients to quickly treat attacks at home, potentially reducing attack severity. The results also demonstrate the benefit of self-administered routine prevention therapy in a real-world patient population. Self-administered therapy potentially allows patients to gain greater control over their attacks, resulting in a reduction in healthcare utilization.