SEVERE CAROTID ATHEROMATOUS STENOSIS REGRESSION AFTER SUBCUTANEOUS ADMINISTRATION OF TOCILIZUMAB

Takayasu arteritis (TA) is a chronic inflammatory disease of unknown etiology that involves large and medium-sized arteries, primarily the aorta and its major branches. TA is a therapeutic challenge because corticosteroids and conventional immunosuppressive agents are not always safe and/or efficacious. Interleukin 6 (IL-6) has emerged as a key cytokine in the pathogenesis of TA and its serum levels have been shown to well correlate with disease activity.
We report the case of a normotensive, normolipemic 19 years old female patient with TA refractory to conventional immunosuppressive agents successfully treated by subcutaneous administration of tocilizumab. The follow-up period was 3.6 years. At the first evaluation, despite the current use of prednisone at dosage of (50 mg/kg/day), the patients presented with high clinical indices of disease activity, and high inflammatory markers; moreover, at the age of 22-years old, ultrasonography doppler scan diagnosed a severe atheromatous carotid involvement, with estimated stenosis of 75%, bilaterally; after tocilizumab was started, the patient was clinically and instrumentally evaluated every 16 weeks, and a progressive normalization of clinical and bio-humoral indices of disease was observed (stably normal since the 5th month of treatment); prednisone dosage could be consistently tapered and finally stopped since the 4th month of treatment. At the last US evaluation (6th month of treatment), carotid stenosis were estimated as 45%, bilaterally. At 12th month since the treatment has been started the carotid stenosis has been estimated lower than 25%, bilaterally. No significant side effects have been reported, and the patient is continuing to take the drug.
Subcutaneous administration of tocilizumab appears a good option in refractory TA with an effective steroid-sparing effect. In addition, it seems to have very favorable effects on endothelial function improving cIMT, and significantly reducing artery hypertrophy.