Transcranial direct current stimulation is safe and effective in autoimmune myopathies: a randomised, double-blind, sham-controlled trial.

OBJECTIVES: We aimed to assess the safety and efficacy of transcranial direct current stimulation (tDCS) in patients with systemic autoimmune myopathies (SAMs). METHODS: This prospective, randomised, sham-controlled, double-blind, study included 20 patients with SAMs allocated to receive sham or active tDCS (2mA, 20 minutes, 3 days). Electrodes were positioned with the anode over the C1 or C2, whereas the cathode was placed over the Fp2 or Fp1, respectively. The groups were evaluated in four periods with specific questionnaires and functional tests: pre-stimulation and after 30 minutes, three weeks, and eight weeks post-tDCS. RESULTS: Two patients from the sham group withdrew after the three sessions. The demographic data, type of myositis, disease duration, and disease status were comparable between the active and sham tDCS groups. After interventions, in the active tDCS group, the physical aspects of SF-36 in week eight, mean and better timed up-and-go test at each evaluation, peak torque of stimulated inferior limb extension improved significantly (p<0.05). The emotional aspect of SF-36 decreased only in the active tDCS group (p<0.001). The patients' adherence to the protocol was 100% and no serious adverse event was reported, including disease relapses. CONCLUSIONS: This study evidences the safety of tDCS, as well as its potential efficacy in improving muscle strength and function in SAMs patients. More studies with a larger sample and longer tDCS sessions are necessary to corroborate the results of the present study.

Systemic autoimmune myopathies: a prospective phase 4 controlled trial of an inactivated virus vaccine against SARS-CoV-2.

OBJECTIVES: To evaluate immunogenicity and safety of an inactivated SARS-CoV-2 vaccine in systemic autoimmune myopathies (SAMs) and the possible influence of baseline disease parameters, comorbidities and therapy on immune response. METHODS: This prospective controlled study included 53 patients with SAMs and 106 non-immunocompromised control group (CTRL). All participants received two doses of the Sinovac-CoronaVac vaccine (28-day interval). Immunogenicity was assessed by anti-SARS-CoV-2 S1/S2 IgG seroconversion (SC), anti-S1/S2 IgG geometric mean titre (GMT), factor increase GMT (FI-GMT), neutralizing antibodies (NAb) positivity, and median neutralizing activity after each vaccine dose (D0 and D28) and six weeks after the second dose (D69). Participants with pre-vaccination positive IgG serology and/or NAb and those with RT-PCR confirmed COVID-19 during the protocol were excluded from immunogenicity analysis. RESULTS: Patients and CTRL had comparable sex (P>0.99) and age (P=0.90). Immunogenicity of 37 patients and 79 CTRL-naïve participants revealed at D69, a moderate but significantly lower SC (64.9% vs 91.1%, P<0.001), GMT [7.9 (95%CI 4.7-13.2) vs 24.7 (95%CI 30.0-30.5) UA/ml, P<0.001] and frequency of NAb (51.4% vs 77.2%, P<0.001) in SAMs compared with CTRL. Median neutralizing activity was comparable in both groups [57.2% (interquartile range (IQR) 43.4-83.4) vs 63.0% (IQR 40.3-80.7), P=0.808]. Immunosuppressives were less frequently used among NAb+ patients vs NAb- patients (73.7% vs 100%, P=0.046). Type of SAMs, disease status, other drugs or comorbidities did not influence immunogenicity. Vaccine-related adverse events were mild with similar frequencies in patients and CTRL (P>0.05). CONCLUSION: Sinovac-CoronaVac is safe and has a moderate short-term immunogenicity in SAMs, but reduced compared with CTRL. We further identified that immunosuppression is associated with diminished NAb positivity. TRIAL REGISTRATION: COVID-19 CoronaVac in Patients With Autoimmune Rheumatic Diseases and HIV/AIDS (CoronavRheum), http://clinicaltrials.gov/ct2/show/NCT04754698.