Eculizumab use in catastrophic antiphospholipid syndrome (CAPS): Descriptive analysis from the "CAPS Registry"

To describe the real-world experience of eculizumab use in patients with catastrophic antiphospholipid syndrome (CAPS) according to the information provided by the "CAPS Registry".

We analyzed the demographic, clinical and immunological data from all the patients included in the "CAPS Registry" treated with eculizumab and described the indications for eculizumab administration, dose, outcome, use of prophylactic vaccines and adverse effects.

The "CAPS Registry" currently includes 584 patients from whom 39 (6.7%) were treated with eculizumab (it was used as a rescue therapy in 30 cases while in 6 cases it was used as first line therapy). Mean age of eculizumab treated patients was 39 years (SD = 14.6), 72% were female, 77% had a primary APS and 79% had a precipitating factor before the CAPS event. Thrombocytopenia was present in 28 (72%) cases and features of microangiopathic hemolytic anemia were present in 15 (38.5%). Twenty-nine (74.4%) patients recovered from the episode of CAPS (four showed only partial remission). Symptoms worsened in 9 patients, from whom 5 finally died despite the treatment. There was only one relapse after a median follow up of 10.7 months. The most common treatment regimen was 900 mg weekly for four weeks and 1200 mg fortnightly.

According to the real-world experience provided by the "CAPS Registry", eculizumab can be considered in some patients with CAPS refractory to previous therapies, especially if they present with features of complement-mediated thrombotic microangiopathy.