P98 Weekly pulses of oral azithromycin for the treatment of EGFRIs related papulopustular eruption

Abstract

Introduction Papulopustular eruption is the most common cutaneous side effect of epidermal growth factor receptor inhibitors (EGFRIs). Azithromycin, an azalide analogous to erythromycin with extended mode of action, has been found to be an effective alternative to tetracyclines in the treatment of inflammatory acne and rosascea. Aim To investigate the efficacy and safety of pulsed azithromycin doses in the treatment of EGFRI- related papulopustular eruption. Methods We performed a retrospective analysis of patients under EGFRIs who exhibited papulopustular eruption and were intolerant to tetracyclines or unwilling to receive antibiotic treatment. All patients showed grade 2 papulopustular eruption. Patients received treatment with pulsed azithromycin doses of 500 mg daily, given in 3 consecutive days per week for 4 weeks, in conjunction or not with topical treatment. The therapeutic responses were evaluated based on symptomatic improvement and the reduction of erythema, pustules and pruritus. Any side effect related to the use of azithromycin was routinely recorded. Results Twelve patients (4 females and 8 males) were included in our analysis. Eleven patients were diagnosed with NSCLC and one patient with pancreatic cancer. Five patients were treated with cetuximab and 7 patients with erlotinib. Seven patients also received topical treatment, 2 with mild topical corticosteroids twice daily, 2 with metronidazole cream twice daily and 3 with pimecrolimus cream twice daily. Treatment with azithromycin showed a significant reduction of the number of lesions in 8 out of 12 patients, with 6 showing complete resolution of the rash. The mean duration of treatment was 3 weeks. In most of the cases the reduction of the lesions appeared after 2 weeks of treatment. Two patients showed deterioration of skin toxicity, one of which had a>50% reduction of skin lesions after 2 weeks of doxycycline treatment 200 mg/day. No significant side effects were recorded in patients treated with azithromycin. Conclusions Systemic antibiotics currently used in the treatment of EGFRI-related papulopustular eruptions are frequently associated with uncomfortable side effects and inconvenience due to the prolonged course of treatment. Weekly pulses of azithromycin are safe, well tolerated, and effective and promote increased patient adhesion to the treatment. A prospective study is needed in order to further evaluate treatment effectiveness and safety.