DOP77 The effectiveness of combination therapy mesenchymal stromal cells and certolizumab pegol in perianal lesions in Crohn's disease

Perianal fistulas are common types of fistulas in Crohn's disease (CD). Mesenchymal stromal cells (MSC), which have immunomodulatory properties and high regenerative potential, are currently also used for the treatment of fistula CD. The objective of this study was to compare the effectiveness of combined therapy (local and systemic administration) of bone marrow MSC, the effectiveness of combined therapy of MSC (local administration), and certolizumab pegol (CZP) according to the scheme and monotherapy of CZP according to the scheme of the frequency of healing of simple perianal fistulas in CD. Fifty-four patients with CD with perianal lesions were divided into three groups depending on the method of therapy. The first group of patients aged 19 to 58 years (Me-29) (n = 18) received the culture of MSC systematically according to the scheme and locally: 40 million MSC—4 injection points of 1 ml of physiological solution containing 10 million MSC were administered along the perimeter of the fistula. Then, after 4 and 8 weeks, 40 million MSC were re-introduced into the fistula area. The second group of patients with CD (n = 18) aged 20 to 68 years (Me-36) received MSC locally and anticytokine therapy with CP according to the scheme. The third group of patients with CD (n = 18) aged 20 to 62 years (Me-28) received anticytokine therapy for CZP according to the scheme. The dynamics evaluated the complete closure of the external opening of the fistula. Ano-and rectosigmoscopy was performed 2, 6, and 12 months after the start of therapy. After 2 months in the first group of patients the healing of simple fistulas was observed in 7/18 (38.9%), in the second group the healing of simple fistulas in 14/18 (77.8%) (OR-5.5; 95% CI 1.28–23.7; p = 0.043 in comparison with the first group). In the third group, 6/18 patients (33.3%) (OR 0.26; 95% CI 0.07–0.97; p = 0.019 in comparison with the first group). After 6 months in the first group receiving MSC, the healing of simple fistulas persisted in 6/18 (33.3%), in group second 14/18 (77.8%) (OR-7.0; 95% CI 1.59–30.8; p = 0.019 in comparison with the first group). In the third group, in 5/18 patients (27.8%) (OR 9.1; 95% CI 1.99–41.45; p = 0.008 in comparison with the second group). After 12 months in the first group receiving MSCS, the healing of simple fistulas persisted in 8/18 (44.4%), in the second group-in 15/18 (83.3%) (OR 6.2; 95% CI 1.33–29.43; p = 0.038 in comparison with the first group). In the third group, in 7/18 patients (38.9%) (OR 7.857; 95% CI 1.65–37.4; p = 0.017 in comparison with the first group). Combined cell and anti-cytokine therapy with CZP of CD with perianal lesions promotes more frequent and prolonged closure of simple fistulas, compared with MSC monotherapy and CZP monotherapy.