Discovery and preclinical evaluation of KYS202004A, a novel bispecific fusion protein targeting TNF-α and IL-17A, in autoimmune disease models.

The treatment of autoimmune and inflammatory diseases often requires targeting multiple pathogenic pathways. KYS202004A is a novel bispecific fusion protein designed to antagonize TNF-α and IL-17A, pivotal in the pathophysiology of autoimmune and inflammatory diseases. Our initial efforts focused on screening for optimal structure by analyzing expression levels, purity, and binding capabilities. The binding affinity of KYS202004A to TNF-α and IL-17A was evaluated using SPR. In vitro, we assessed the inhibitory capacity of KYS202004A on cytokine-induced CXCL1 expression in HT29 cells. In vivo, its efficacy was tested using a Collagen-Induced Arthritis (CIA) model in transgenic human-IL-17A mice and an imiquimod-induced psoriasis model in cynomolgus monkeys. KYS202004A demonstrated significant inhibition of IL-17A and TNF-α signaling pathways, outperforming the efficacy of monotherapeutic agents ixekizumab and etanercept in reducing CXCL1 expression in vitro and ameliorating disease markers in vivo. In the CIA model, KYS202004A significantly reduced clinical symptoms, joint destruction, and serum IL-6 concentrations. The psoriasis model revealed that KYS202004A, particularly at a 2  mg/kg dose, was as effective as the combination of ixekizumab and etanercept. This discovery represents a significant advancement in treating autoimmune and inflammatory diseases, offering a dual-targeted therapeutic approach with enhanced efficacy over current monotherapies.

An immuno-blocking agent targeting IL-1ß and IL-17A reduces the lesion of DSS-induced ulcerative colitis in mice.

In recent decades when biological agents have flourished, a part of patients suffering from inflammatory bowel disease (IBD) have received the treatment of tumor necrosis factor inhibitors or IL-1 antibodies. This study aims to investigate the anti-colitis effects of bispecific antibody (FL-BsAb1/17) targeting IL-1ß and IL-17A comparing with TNF-α soluble receptor medicine etanercept. IBD model in mice was established by drinking 3% DSS (dextran sulfate sodium salt). On the first day of drinking DSS, treatments with etanercept (5 mg/kg) or different doses of FL-BsAb1/17 (1 mg/kg, 5 mg/kg, and 10 mg/kg) were started by intraperitoneal injection every other day. The results demonstrated that FL-BsAb1/17 treatment was more effective than etanercept at the same dose (5 mg/kg) in relieving the typical symptom of ulcerative colitis induced by DSS (such as the severity score and intestinal shortening), and down-regulating the expression of inflammatory factors (IL-17A, IL-6, IL-12, IL-22, IL-1ß, IL-23, TNF-α) in the serum and colon. FL-BsAb1/17 could also reduce the degree of intestinal fibrosis. The same dose of FL-BsAb1/17 (5 mg/kg) performed better than etanercept in down-regulating MDA and up-regulating SOD (superoxide dismutase), CAT (catalase), and T-AOC (total antioxidant capacity) in serum. Both FL-BsAb1/17 and etanercept could reduce the transcription of Bax and increase the transcription of Bcl-2 and slow down apoptosis in colitis colon tissue. We conclude that the blocking of IL-1ß and IL-17A can inhibit DSS-induced ulcerative colitis and FL-BsAb1/17 may have potential to become a new dual-target candidate for colitis treatment.

A novel bispecific antibody alleviates bleomycin-induced systemic sclerosis injury.

Systemic sclerosis (SSc) is induced by variety of factors and eventually causes multiple organ damage. In recent years, biological agents targeting cytokines and cell surface molecules have gradually come to market. Here, the anti-inflammatory and antifibrotic effects of a novel bispecific antibody (FL-BsAb1/17) targeting interleukin-17A (IL-17A) and interleukin-1ß (IL-1ß) were detected. Bleomycin (BLM) was subcutaneously injected for 21 consecutive days to establish the SSc mouse model, and mice were subsequently treated with etanercept or different doses (1, 5, 10 mg/kg) of FL-BsAb1/17. The results showed that FL-BsAb1/17 treatment (10 mg/kg, 5 mg/kg) significantly attenuated BLM-induced SSc-like inflammation by inhibiting the expression of inflammatory factors (IL-17A, IL-1ß, IL-8, IL-22, IL-23, IL-6) and fibrosis, with specific outcomes of dermis thickening and lung fibrosis, by inhibiting the expression of fibrotic factors (TGF-ß, α-sma, Col-1, Col-3) in the serum, skin and lungs. In addition, FL-BsAb1/17 (10 mg/kg, 5 mg/kg) downregulated protein levels of TGF-ß and phosphorylated Smad2/3 in the skin and lungs and reduced collagen 1 protein levels. This indicated that FL-BsAb1/17 can inhibit the development of fibrosis by inhibiting the TGF-ß/Smad2/3 signaling pathway. FL-BsAb1/17 (10 mg/kg, 5 mg/kg) could also effectively reduce the content of MDA, increase the activity of SOD and CAT, and improve the total antioxidant capacity (T-AOC). In conclusion, FL-BsAb1/17 alleviated BLM-induced SSc by downregulating inflammatory cascades, relieving oxidative stress and inhibiting TGF-ß/Smad2/3 signaling. These data suggest that FL-BsAb1/17 has potential as a novel therapeutic candidate for SSc.