Background

Biologic medications for severe asthma enable maintenance oral corticosteroid (mOCS) reduction or cessation for many patients. However, there is a small risk of emergent adrenal insufficiency in patients withdrawing from mOCS, and little consensus about how to monitor or avoid this.

Aim

Assess the success rate of a bespoke formal mOCS withdrawal pathway for severe asthma patients on biologics.

Methods

Patients on mOCS and biologics, who had reduced mOCS to 5mg Prednisolone daily, entered the mOCS withdrawal pathway. Prednisolone was further reduced by 1mg every 6 weeks to 3mg daily then serum cortisol was checked. Patients with cortisol ?25 nmol/L followed a 20-week prednisolone weaning plan until mOCS cessation and had cortisol re-checked 12 weeks after cessation. Patients with cortisol below 25 nmol/L were referred for endocrinology assessment and not included. Patients received education about adrenal insufficiency symptoms and ?sick day rules?.

Results

39 patients followed the pathway. 33 patients (85%) successfully weaned off mOCS, and 6 patients were unable to. In successfully weaned patients mean (SD) cortisol on 3mg Prednisolone was 244 (162) nmol/L, rising to 317 (119) nmol/L 12 weeks after completion of weaning (p=0.01). In 6 patients who failed to wean, mean (SD) cortisol on 3mg Prednisolone was 107 (94) nmol/L. Reasons for weaning failure were symptoms of adrenal insufficiency or cortisol <25 nmol/L at 12 weeks after mOCS cessation. These patients remain on 2-5mg of Prednisolone. There were no serious adverse events.

Conclusion

Our pathway facilitated successful withdrawal of mOCS in 85% of patients with cortisol ?25 nmol/L on 3mg Prednisolone, with no adverse events.