OBJECTIVES: Erythropoietic protoporphyria (EPP) and X-linked protoporphyria (XLP) are rare genetic disorders of the heme biosynthetic pathway resulting in severe cutaneous phototoxicity reactions. Symptoms usually present in early childhood and include extremely painful photosensitivity reactions preceded by a “prodrome” of tingling, stinging, and/or burning of sun-exposed skin, with few treatment options. There are limited data regarding how EPP and XLP are managed in real-world settings. This study aims to describe treatment patterns and healthcare resource utilization among patients diagnosed with EPP and/or XLP in the United States.

METHODS: A retrospective medical record review of patients diagnosed with EPP and/or XLP at any time prior to July 1, 2020, was conducted. Outcomes included demographic and clinical characteristics, timing of diagnosis, diagnostic testing, therapy recommendations, office visits, emergency department visits, and hospitalizations.

RESULTS: Data were abstracted for 299 patients with EPP and 91 patients with XLP by 136 physicians across the United States. Mean (SD) age at diagnosis was 24.2 (19.1) years. Genetic testing (FECH or ALAS2) was conducted for 227 patients (59%), of whom 95% had confirmed mutations. Other common tests were liver function (n=247; 44% were abnormal) and blood erythrocyte protoporphyrin (n=236; 89% were elevated). Following diagnosis, most patients received recommendations to protect themselves from light exposure (sunscreen, 85%; lifestyle modification, 83%). Other common therapies recommended were supplements (50%), oral beta-carotene (39%), pain relievers (35%), and afamelanotide (19%). Within 12 months of diagnosis, the mean (SD) number of office visits, emergency department visits, and inpatient hospitalizations related to EPP/XLP were 4.0 (3.5), 0.8 (1.6), and 0.4 (1.3), respectively.

CONCLUSIONS: Our findings point to several unmet needs of patients with EPP and XLP. Although symptoms usually present in early childhood, diagnosis commonly occurs during adulthood, symptom management is primarily limited to sun protection, and outpatient office visits are frequent.