Efficacy of Olokizumab against Comorbid Depressive Disorder in Patients with Rheumatoid Arthritis: Preliminary Results of the Study

Abstract

Interleukin (IL) 6 plays an important role in the pathogenesis of depression comorbid with rheumatoid arthritis (RA), and IL-6 inhibitors used to treat patients with RA may have an antidepressant effect. The objective of the study was to evaluate the effectiveness of Russian iIL-6 olokizumab (OKZ) in reducing symptoms of depression in patients with moderate/high RA activity. To date, 49 RA patients have been included, of which 43 (87.7%) are women, with an average age of 47.8 ± 12.8 years; with a predominant high activity of RA according to DAS28 (CRP) indices (89.8%), SDAI (79.6%) and CDAI (75.5%) and inefficacy of stable 12-week therapy with сDMARDs. In all patients, a psychiatrist, in accordance with ICD-10, diagnosed depression (chronic or recurrent) of varying severity during a semi-structured interview. At week 0, all patients were randomized by the method of sequential numbers in a ratio of 1 : 1 : 1 to one of the three study groups: group 1-cDMARDs + OKZ 64 mg subcutaneously once every 4 weeks (n = 18); group 2-cDMARDs + OKZ 64 mg subcutaneously once every 4 weeks + psychopharmacotherapy (PPT) (n = 26); group 3-cDMARDs + PPT (n = 5). The duration of the study is 24 weeks. The dynamics of depression severity was assessed on the PHQ-9, MADRS scales; anxiety, on HAM-A; experimental psychological projective techniques were also used. After 12 and 24 weeks of therapy, there was a significant decrease in the severity of depression and anxiety in all groups of patients. However, the difference between the final and initial values of all scales was statistically significantly greater (p <0.05) in the groups of patients receiving PPT: cDMARDs + OKZ + PPT (Δ_{PHQ-9 24-0} = -6.75 ± 3.91; Δ_{MADRS 24-0} = -22.5 ± 4.83; Δ_{HAM-A 24-0} = -14.6 ± 5.37) and cDMARDs + PPT (Δ_{PHQ-9 24-0} = -15.5 ± 3.53; Δ_{MADRS 24-0} = -25.0 ± 1.41; Δ_{HAM-A 24-0} = -18.5 ± 3.53), compared with the cDMARDs + OKZ group (Δ_{PHQ-9 24-0} = -4.00 ± 3.89; Δ_{MADRS 24-0} = -5.75 ± 8.29; Δ_{HAM-A 24-0} = -8.50 ± 8.21). According to a semi-structured interview with a psychiatrist and design experimental psychological techniques, the proportion of patients without depression after 24 weeks of therapy was significantly higher in the groups of patients receiving PPT: 90% in the group of cDMARDs + OKZ + PPT and 100%-cDMARDs + PPT, as opposed to 25% in the group of cDMARDs + OKZ. OKZ therapy contributed to the normalization of night sleep but did not lead to a decrease in the frequency and severity of cognitive disorders (CDs). OKZ has an antidepressant effect, leads to a decrease in the frequency of sleep disorders. However, a complete regression of depression symptoms when OKZ is prescribed without PPT is possible only in 25% of RA patients, mainly in the patients with mild depression. A combination of OKZ and PPT is optimal for the complete regression of depression and anxiety and a decrease in the frequency and severity of CDs.

Keywords: cognitive disorders; depression; interleukin-6; olokizumab; rheumatoid arthritis.