Long-term efficacy and safety of netakimab in the treatment of ankylosing spondylitis: results of Phase III international, multicenter, randomized double-blind clinical trial BCD-085-5/ASTERA

Netakimab (NTK) is a humanized anti-interleukin-17A monoclonal antibody. To date, the drug has been approved to treat ankylosing spondylitis (AS), psoriatic arthritis, and plaque psoriasis. The paper gives the data obtained during 52-week follow-up of AS patients in the phase III ASTERA study.Objective: to study the efficacy and safety of NTK when used long in patients with active AS.Patients and methods. The investigation enrolled 228 patients with active AS, in whom nonsteroidal anti-inflammatory drugs or biological agents were ineffective. The patients were randomized in a 1:1 ratio to receive NTK 120 mg or placebo. The drug was administered subcutaneously at weeks 0, 1, 2, and then once every 2 weeks. Patients who received placebo and achieved a 20% improvement according to the ASAS criteria (ASAS20) were excluded from the study at week 16. At this week, patients who took placebo and did not achieve an ASAS20 response were switched to subcutaneous NTK at 120 mg dose once every two weeks. The follow-up period was 52 weeks.Results and discussion. Patients with active AS who received NTK were more likely to respond to treatment than those who took placebo. The proportion of people who achieved 40% improvement (ASAS40) during treatment with NTK increased throughout the follow-up period and amounted to 80.7% at week 52. Positive changes were achieved in all used clinical and laboratory parameters of AS activity. There was also a decrease in inflammatory changes, as shown by magnetic resonance imaging (MRI). The adverse events (AEs) were mainly laboratory abnormalities and upper respiratory tract infections. Treatment-related AEs were recorded in no more than one third of patients and they were mild to moderate. Severe AEs were singular.Conclusion. Response to NTK therapy generates in the first weeks of drug use and increases throughout a year. The safety profile of NTK when used long is generally favorable.