# Canakinumab treatment in patients with colchicine-resistant familial mediterranean fever: a multicenter observational study

## TL;DR

Canakinumab is effective in treating colchicine-resistant familial Mediterranean fever, significantly reducing inflammation and kidney damage.

## Contribution

This study is the first to show Canakinumab's efficacy in reducing serum creatinine levels in colchicine-resistant FMF patients.

## Key findings

- 80% of patients achieved complete remission with Canakinumab treatment.
- Canakinumab significantly reduced inflammation markers and proteinuria in patients with AA-amyloidosis.
- Only one patient discontinued treatment due to insufficient arthritis relief.

## Abstract

Anti-interleukin-1 agents have known beneficial effects in the treatment of colchicine-resistant familial Mediterranean fever (cr-FMF); however, studies to date have tended to have small sample sizes and to be based on pooled data. The present study investigates the efficacy of Canakinumab (CAN) in a homogeneous cohort of cr-FMF cases.

The study included patients who underwent treatment in three tertiary rheumatology departments, whose electronic medical records were reviewed retrospectively. The inclusion criteria were presence of colchicine resistant disease activity or persistent proteinuria secondary to AA-amyloidosis, and treatment with CAN for at least 6 months. Clinical and laboratory parameters were assessed before and after CAN treatment.

The study included 65 patients with a mean age of 38.2 ± 13.8 years, with a mean disease duration of 23.7 ± 11.4 years and a mean colchicine dosage of 1.5 ± 0.6 mg/day. Of the total, 60% of the patients had an M694V homozygous mutation, and 41.5% were resistant to Anakinra. Furthermore, 25 had FMF-related amyloidosis, and 16 were renal transplant recipients. The mean CAN treatment duration was 31.3 ± 23.1 months, and 80% of patients achieved complete remission, while 20% achieved partial remission. Erythrocyte sedimentation rate, C-reactive protein, frequency of attacks, and patient global assessment decreased significantly after CAN (p < 0.001 for each). The mean serum creatinine level (mg/dl) decreased from 2.1 ± 0.8 to 1.4 ± 0.8 (p < 0.001), and median proteinuria (mg/day) decreased from 1475 to 675 (p < 0.001) in patients with AA-amyloidosis. Only one patient with chronic monoarthritis affecting the wrist discontinued CAN due to insufficient arthritis relief.

Canakinumab demonstrates excellent efficacy and favorable safety as a treatment for cr-FMF. Our study is the first to indicate the efficacy of CAN in reducing serum creatinine levels.