710 Background: TSN1611 is a novel small molecule KRAS G12D inhibitor targeting both the active (GTP-bound/On) and inactive (GDP-bound/Off) forms of KRAS G12D protein. TSN1611 showed high potency and selectivity against KRAS G12D mutant tumor cells in vitro and effectively inhibited tumor growth in several pancreatic ductal carcinoma (PDAC), colorectal cancer (CRC) and non-small cell lung cancer models (NSCLC) in vivo. Methods: A phase 1/2 study of TSN1611 was initiated to enroll patients (pts) with advanced solid tumors harboring KRAS G12D mutation. The study comprised a Phase 1a dose escalation part following a BOIN design with accelerated titration to determine the maximum tolerated dose (MTD), recommended Phase 2 dose (RP2D) and pharmacokinetics (PK), followed by a Phase 1b part for dose optimization to compare different recommended doses and a Phase 2 part to evaluate the efficacy of TSN1611 across various tumor types. Pts received oral TSN1611 tablets twice daily (BID), until disease progression, unacceptable toxicity, or patient withdrawal. Results: As of Aug 29, 2025, 76 pts received TSN1611 from 50 to 1200 mg BID in Phase 1 part (46 in Phase 1a and 30 in Phase 1b). Median age was 61 yrs (range 22-81). The median prior lines of systemic therapy were 2 (range 0-7). No dose-limiting toxicity was reported and MTD was not reached. The RP2D was established as 1200 mg BID. Patients were randomized to 800 mg and 1200 mg BID for dose optimization in Phase 1b part. Overall, the most common (≥ 10% out of 76 pts) treatment-related adverse events (TRAEs) were nausea (52.6%), vomiting (43.4%), diarrhea (40.8%), anemia (18.4%), decreased white blood cell count (14.5%), fatigue and decreased neutrophil count (11.8% each), and increased ALT and decreased appetite (10.5% each). All TRAEs were Grade 1 or 2 (CTCAE v5.0), except for one case each (1.3%) of Grade 3 decreased WBC count and Grade 3 anemia. No serious TRAE was observed. TRAEs led to dose interruption in 9 pts (11.8%) and dose reduction in 3 pts (3.9%); however, no treatment discontinuation due to TRAEs occurred. Tumor response was observed at doses ≥ 600 mg BID; among the 7 evaluable pts with NSCLC who had post-baseline tumor evaluation, the objective response rate (ORR) was 42.9% (3/7 PR) and the disease control rate (DCR) was 100% (all 7 pts achieved stable disease or better). Among evaluable pts at 800 mg and 1200 mg BID, the ORR was 36.4% (4/11 PR) and DCR was 72.7% (8/11) in PDAC pts who had received 1-2 prior lines of therapy. Enrollment into the Phase 2 portion of the study is ongoing, and more data will be available at the conference presentation. Conclusions: TSN1611 demonstrated promising clinical efficacy in pts with KRAS G12D mutant tumors, with a well-tolerated safety profile. These results support further evaluation of TSN1611 as a monotherapy and in combination therapies in KRAS G12D mutant tumors. Clinical trial information: NCT06385925 .

HER2 is overexpressed in approximately 15-20% of cancers and is associated with aggressive disease progression. We developed JSKN003, a bispecific HER2-targeted antibody-drug conjugate (ADC), through site-specific conjugation technology based on N-glycosylation engineering. JSKN003 maintains a biantennary glycan structure and exhibits superior structural homogeneity, optimized hydrophilicity, and reduced aggregation compared to conventional thiol-maleimide chemistry. In preclinical models JSKN003 demonstrated potent antitumor efficacy, inducing tumor regression in multiple HER2-expressing tumors, such as NCI-N87, BxPC-3, and PDX tumor models. Mechanistically, JSKN003 binds specifically to HER2, undergoes efficient internalization, and traffics to the lysosome, where the payload DXd is released, leading to DNA damage and apoptosis. JSKN003 retained its cytotoxic activity against trastuzumab-resistant cells, attributed to efficient payload delivery and blockade of downstream HER2 signaling pathways, demonstrating the potential to overcome clinical trastuzumab resistance. The safety profile of JSKN003 was evaluated in cynomolgus monkeys and was found to be acceptable, with no severe toxicities observed at therapeutic doses. JSKN003 demonstrated excellent antitumor activity and a favorable safety profile in clinical trials, highlighting its potential as a promising therapeutic option for patients with HER2-positive tumors. These findings suggest that JSKN003 could be a valuable therapeutic strategy with excellent efficacy and safety for HER2-expressing tumors in the clinical setting.

Growing evidence positions Factor XI (FXI) as a promising anticoagulation target, where its role in pathological thrombus formation significantly outweighs its contribution to physiological hemostasis. This distinctive pathophysiological profile has propelled FXI inhibition as a transformative therapeutic paradigm, with multiple candidates in Phase I-III trials spanning venous thromboembolism prophylaxis to arterial thrombosis prevention. Building on emerging insights into FXI-mediated vascular inflammation and remodeling, we herein unveil the first preclinical evidence supporting KN060-a humanized dual-domain antibody simultaneously targeting FXI-A2/A3 epitopes-as a novel antihypertensive agent. In angiotensin II-challenged mice, 5-week KN060 monotherapy (10 mg/kg triweekly) elicited sustained systolic blood pressure (SBP) reduction of 27.8 mmHg (120.7 mmHg in KN060 group vs 148.5 mmHg in vehicle control group). Furthermore, in spontaneously hypertensive rats, 9-week KN060 monotherapy (15 mg/kg twice weekly) achieved sustained SBP reduction of 34.7 mmHg (172.2 mmHg in KN060 group vs 206.9 mmHg in vehicle control group), concomitantly reducing left ventricular mass (0.67 g vs 0.773 g) and aortic relative media thickness (28.74 vs 31.59). Notably, co-administration of KN060 (3 mg/kg) with losartan (5 mg/kg) in SHRs demonstrated synergistic efficacy, achieving greater SBP reduction than losartan monotherapy (ΔSBP: -23.7 mmHg vs -15.9 mmHg). These findings establish KN060 as a first-in-class therapeutic bridging anticoagulation and vascular protection. Its unique bispecific architecture enables near-complete FXI activity inhibition while preserving hemostatic capacity, addressing critical limitations of conventional RAAS blockers in resistant hypertension. With an ongoing Phase Ib trial in primary hypertension patients (NMPA approval No CXSL2400827), KN060 emerges as a transformative candidate for precision management of hypertension.

BACKGROUND AND OBJECTIVES:Envafolimab is the first and only globally approved subcutaneously injectable PD-L1 antibody for the treatment of instability-high (MSI-H) or DNA mismatch repair deficient (dMMR) advanced solid tumors in adults, including those with advanced colorectal cancer that has progressed after treatment with a fluoropyrimidine, oxaliplatin, and irinotecan. The aim of this investigation was to examine the pharmacokinetic and exposure-response (E-R) profile of envafolimab in patients with solid tumors to support the approval of fixed and alternative dose regimens. METHODS:In this study, a population pharmacokinetic (PopPK) modeling approach will be employed to quantitatively evaluate intrinsic and extrinsic covariates. Additionally, PopPK-estimated exposure parameters were used to evaluate E-R relationship for safety and efficacy to provide a theoretical basis for recommending optimal treatment regimens. Simulations were performed on the dosing regimens of body weight-based regimen of 2.50 mg/kg QW, fixed dose 150 mg QW, and 300 mg Q2W for the selection of alternative dosing regimens. Data from 4 clinical studies (NCT02827968, NCT03101488, NCT03248843, and NCT03667170) were utilized. RESULTS:The PopPK dataset comprised 182 patients with 1810 evaluable envafolimab concentration records. Finally, a one-compartment model incorporating first-order absorption, first-order linear elimination, and time-dependent elimination according to an Emax function was found to accurately describe the concentration-time data of envafolimab in patients with advanced solid tumors. Creatinine clearance and country were identified as statistically significant factors affecting clearance, but had limited clinical significance. A relative flat exposure-response relationship was observed between early measures of safety and efficacy to verify that no dose adjustment is required. Simulation results indicated that 2.50 mg/kg QW, 150 mg QW, and 300 mg Q2W regimen yield similar steady-state exposure. CONCLUSIONS:No statistically significant difference was observed between weight-based and fixed dose regimens. Model-based simulation supports the adoption of a 150 mg weekly or 300 mg biweekly dosing regimen of envafolimab in the solid tumor population, as these schedules effectively balance survival benefits and safety risks.

KN046, a bispecific antibody targeting PD -L1 and CTLA-4, presents a promising therapeutic option for metastatic non -small cell lung cancer (NSCLC). In this multicenter phase 2 trial, patients with nonsquamous (nonsq) NSCLC receive pemetrexed, whereas those with sq-NSCLC receive paclitaxel, plus KN046 and carboplatin. Following four cycles, maintenance therapy includes KN046 with pemetrexed for non-sq-NSCLC and KN046 for sq-NSCLC. The objective response rate is 46.0%, and the median duration of response is 8.1 months. The median progression -free and overall survival are 5.8 and 26.6 months, respectively. The common adverse events include anemia (87.4%), loss of appetite (72.4%), and neutropenia (70.1%). The most prevalent immune -related adverse event is pruritus (28.7%). These findings indicate that first -line treatment with KN046 and chemotherapy is effective and tolerable in metastatic NSCLC patients, warranting further investigation in a larger phase 3 trial. The trial is registered at ClinicalTrials.gov (NCT04054531).

Excessively activated or dysregulated complement activation may contribute to the pathogenesis of a wide range of human diseases, thus leading to a surge in complement inhibitors. Herein, we developed a human-derived and antibody-like C3b-targeted fusion protein (CRIg-FH-Fc) x2, termed CG001, that could potently block all 3 complement pathways. Complement receptor of the immunoglobulin superfamily (CRIg) and factor H (FH) bind to distinct sites in C3b and synergistically inhibit complement activation. CRIg occupancy in C3b prevents the recruitment of C3 and C5 substrates, whereas FH occupancy in C3b accelerates the decay of C3/C5 convertases and promotes the factor I-mediated degradation and inactivation of C3b. CG001 also showed therapeutic effects in alternative pathways-induced hemolytic mouse and classical pathways-induced mesangial proliferative glomerulonephritis rat models. In the pharmacological/toxicological evaluation in rats and cynomolgus monkeys, CG001 displayed an antibody-like pharmacokinetic profile, a convincing complement inhibitory effect, and no observable toxic effects. Therefore, CG001 holds substantial potential for human clinical studies.

Excessively activated or dysregulated complement activation may contribute to the pathogenesis of a wide range of human diseases, thus leading to a surge in complement inhibitors. Herein, we developed a human-derived and antibody-like C3b-targeted fusion protein (CRIg-FH-Fc) *2, termed CG001, that could potently block all three complement pathways. CRIg and FH bind to distinct sites in C3b and synergistically inhibit complement activation. CRIg occupancy in C3b prevents the recruitment of C3 and C5 substrates, while FH occupancy in C3b accelerates the decay of C3/C5 convertases and promotes the Factor I-mediated degradation and inactivation of C3b. CG001 also showed therapeutic effects in AP-induced hemolytic mouse and CP-induced MsPGN rat models. In the pharmacological/toxicological evaluation in rats and cynomolgus monkeys, CG001 displayed an antibody-like pharmacokinetic profile, a convincing complement inhibitory effect, and no observable toxic effects. Therefore, CG001 holds substantial potential for human clinical studies.

Figure S7 shows the model of anti-MET VHH pool overcoming MET-targeted cancer therapeutic resistance.

Figure S2 shows the specificity of anti-MET VHH pool on MET in killing cancer cells.

KN052 is a recombinant PDL1/OX40 bispecific antibody which can block PDL1 and PD1/CD80 pathway and active the OX40 signal pathway at the same time. Inhibited PDL1 can block cancer cells to evade T-cell-mediated immune responses and restores T-cell activation and antitumor responses. On the other hand, biding to OX40 which normally expressed on Treg cells can induce ADCC effect and kill the Treg cells. There is a synergistic effect between the blocking of PDL1 pathway and the activation of OX40 signal pathway in cell base assay. PBMCs from four healthy donors showed significant T cell activation effect under the stimulation of superantigen SEB, and the activity of PBMCs from three healthy donors was significantly stronger than that of two single target control antibodies alone and in combination. The anti-tumor activity of KN052 was evaluated by using hPD-L1/hOX40 humanized mouse with MC38 MCA205 syngeneic model. Significant anti-tumor effects were observed in both models in a dose-dependent manner. The HNSTD (highest non-severely toxic dose) of KN052 was determined as 30mg/kg in cynomolgus monkeys. These preclinical data demonstrated acceptable PK and safety profile of KN052 and indicated its potential in a variety of tumors. Citation Format: Ting Xu, Pilin Wang, Yang-Xin Fu, Kangping Guo, Jianjian Peng. KN-052, a novel PDL1/OX40 bispecific antibody, exhibits potent antitumor efficacy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB021.

Abstract In human advanced solid tumors, expression of HER2 protein has been reported in various tumor tissues and a variety of cultured tumor cell lines including breast cancer, gastric cancer, pancreatic cancer, lung cancer, colorectal cancer, and ovarian cancer. Due to the critical roles of HER2 in carcinogenesis, two main targeted therapies have been developed in the past two decades to block the HER2-driven pathways, which include small molecule compounds that inhibit the tyrosine kinase activity of the intracellular domain, and mono-antibodies (mAbs) that target the extracellular domain (ECD) of the receptors. JSKN003 is an antibody-drug conjugate (ADC) comprised of a recombinant, humanized anti-human epidermal growth factor receptor 2 (HER2) bispecific antibody conjugated to a topoisomerase I inhibitor via a dibenzocyclooctyne tetrapeptide linker. The anti-HER2 component, KN026, is a recombinant, humanized bispecific antibody that targets both extra-cellular domains II (pertuzumab binding site) and IV (trastuzumab binding site) of HER2. JSKN003 showed high affinity binding to human HER2 with KDs of 2.209 E-10M, which is comparable to its parental antibody KN026 and bound to NCI-N87 and BxPC-3 cells in a concentration-dependent manner. At the same time JSKN003 showed more extensive and faster internalization than DS8201 on NCI-N87 cells. As expected, JSKN003 showed directly inhibits growth by targeting HER2 positive tumor model (NCI-N87 and BT474 cell models). The single dose and multiple dose pharmacokinetics study in cynomolgus monkey indicated that JSKN003, total antibody and DXd had general linear dynamic characteristics, and pharmacokinetics parameters showed no significant differences between males and females in the range 0.3-30 mg/kg. The HNSTD (highest non-severely toxic dose) of JSKN003 was determined as 30mg/kg in cynomolgus monkeys. These preclinical data suggest that JSKN003 could potentially benefit patients with tumors co-expressing HER2 through improved drug selectivity and efficacy. JSKN003’s safety, tolerability and preliminary anti-tumor activity are currently being evaluated in a first-in-human phase I study in advanced stage solid tumors in Australia (NCT05494918) using a BOIN design. This ADC is targeted on the subjects who has HER2 expression and/or HER2-gene mutation and may address an unmet medical need for these patients.

Figure S3 shows the efficacy of anti-MET VHH pool on tumor growth in individual mouse.

Supplementary Figure Legends 1-5 from Human CD59 Inhibitor Sensitizes Rituximab-Resistant Lymphoma Cells to Complement-Mediated Cytolysis

Figure S5 shows anti-MET VHH pool reducing cell surface-located MET.

Supplementary Materials and Methods from Human CD59 Inhibitor Sensitizes Rituximab-Resistant Lymphoma Cells to Complement-Mediated Cytolysis

Figure S6 shows anti-MET VHH pool significantly inducing MET degradation.

Background: HER2-targeted therapies combined with chemotherapy have improved survival outcomes for patients with metastatic HER2-positive breast cancer. However, for patients progressed after several lines of anti-HER2 combinational therapies, the overall survival (OS) remained unfavorable. Prior studies showed that immunotherapy in combination with chemotherapy or targeted therapy could significantly prolong OS of metastatic breast cancer patients, especially in patients with triple-negative breast cancer. Reports of immunotherapy combined with HER2-targeted therapy are still limited. Here we reported the preliminary results from an ongoing phase II trial assessing the safety and efficacy for KN046 (a bispecific antibody blocks both PD-L1 interaction with PD-1/CD80 and CTLA-4 interaction with CD80/CD86) in combination with KN026 (a bispecific antibody that binds to two different HER2 epitopes shared by trastuzumab and pertuzumab) in HER2-positive metastatic breast cancer patients, who have progressed after prior anti-HER2 combinational therapies.Methods: Female patients with metastatic HER2-positive breast cancer who were previously treated with at least one line of HER2-targeted combinational therapy were enrolled from multiple academic hospitals in China to receive KN046 (iv. 5 mg/kg Q3W) plus KN026 (iv. 30 mg/kg Q3W) until progression, unacceptable toxicities or patient withdrawal. Efficacy was evaluated Q6W per RECIST 1.1. The primary endpoint was objective response rate (ORR). Results: As of the June 20th, 2021, 36 patients with the median age of 53 years (range: 33-67) were enrolled. 30 of 36 patients (83.3%) received ≥3 lines of HER2-targeted combinational therapies in the metastatic setting. 22 patients were evaluable for overall response and all 36 for safety. The ORR was 50.0% (11 of 22, 95% CI: 28.2-71.8), and one patient achieved complete response (CR). And the disease control rate (DCR) was 81.8% (18 of 22, 95% CI 59.7-94.8). The median progression-free survival (PFS) was 5.6 (95%CI 2.5-not reached) months. 34 of 36 (94.4%) patients had treatment-related adverse events (TRAEs) of any grade, while 4 of 36 (11.1%) patients had experienced ≥grade 3 TRAEs. The most common (≥10%) TEAEs were infusion related reaction (36.1%), rash (16.7%), alanine aminotransferase increased (13.9%), diarrhea (13.9%), pruritus (13.9%), aspartate aminotransferase increased (11.1%), and hypokalemia (11.1%). No treatment-related deaths were observed.Conclusions: The combination of KN046 and KN026, as a chemo free regimen, has shown favorable clinical efficacy with manageable side effects in heavily pre-treated patients with metastatic HER2-positive breast cancer. This trial is currently ongoing. ClinicalTrials.gov number, NCT04521179. Citation Format: Jieqiong Liu, Chuangui Song, Xiangcai Wang, Mingli Ni, Xujuan Wang, Lei Chen, Hongwei Yang, Rusen Zhao, Ting Xu, Lin Shen. Preliminary safety and efficacy results of KN046 (an anti-PD-L1/CTLA-4 bispecific antibody) in combination with KN026 (a HER2-targeted bispecific antibody) in patients with metastatic HER2-positive breast cancer: A phase II trial [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-16-04.

Agonistic antibodies targeting co-stimulating receptor OX40 on T cells are considered as important as (or complementary to) the immune checkpoint blockers in cancer treatment. However, none of these agonistic antibodies have reached the late stage of clinical development partially due to the lack of intrinsic potency with the correlation between binding epitope and activity of the antibody not well understood. Here, we identified a novel anti-OX40 agonistic antibody DF004, which stimulated the proliferation of human CD4+ T cells in vitro and inhibited tumor growth in a mouse model. Our crystallography structural studies showed that DF004 binds to the CRD2 region of OX40 while RG7888, an OX40 agonist antibody developed by Roche, binds to CRD3 of OX40 to the diametrically opposite position of DF004. This suggests that the agonistic activities of the antibodies are not necessarily epitope dependent. As their agonistic activities critically depend on clustering or cross-linking, our structural modeling indicates that the agonistic activity requires the optimal positioning of three Fc receptor/antibody/OX40 complexes on the cell membrane to facilitate the formation of one intracellular hexameric TRAF complex for downstream signal transduction, which is relatively inefficient. This may explain the lack of sufficient potency of these OX40 antibodies in a therapeutic setting and sheds light on the development of cross-linking-independent agonistic antibodies.