Phase 3 Multicenter Study on Abelacimab vs. Dalteparin for VTE Recurrence and Bleeding in GI/GU Cancer-Associated VTE Patients

The primary objective of this study is to evaluate whether **abelacimab** is non-inferior to **dalteparin** in preventing the recurrence of **venous thromboembolism (VTE)** over a period of six months following randomization in patients with gastrointestinal or genitourinary cancer who have recently been diagnosed with VTE. The clinical relevance of this objective lies in determining the efficacy of abelacimab as a potential alternative to dalteparin, which could impact treatment protocols for VTE in this patient population. If non-inferiority is established, the study will further assess the superiority of abelacimab over dalteparin.

The clinical trial involves a total of **356 participants** diagnosed with **venous thromboembolism (VTE)** in the context of gastrointestinal or genitourinary cancer. The study population includes both male and female subjects aged 18 years and older, encompassing individuals with confirmed gastrointestinal cancers such as colorectal, pancreatic, gastric, esophageal, gastro-esophageal junction, or hepatobiliary, as well as genitourinary cancers including renal, ureteral, bladder, prostate, or urethra. Participants are selected based on the presence of unresectable, locally advanced, metastatic, or non-metastatic cancer, with no intended curative surgery during the study period. The trial includes individuals with confirmed symptomatic or incidental proximal lower limb deep vein thrombosis (DVT) or pulmonary embolism (PE), who are eligible within 120 hours from the diagnosis of the qualifying VTE. The study requires participants to be on anticoagulation therapy with low molecular weight heparin (LMWH) for at least six months. The trial population is characterized by a vulnerable group, and all participants must be able to provide written informed consent. Lifestyle factors such as diet and physical activity are not specified in the available data.

The clinical trial is a **randomized**, open-label, blinded endpoint evaluation, phase 3 study designed to compare the effect of **abelacimab** relative to **dalteparin** on the recurrence of **venous thromboembolism (VTE)** and bleeding in patients with gastrointestinal or genitourinary cancer-associated VTE. The primary objective is to assess whether abelacimab is non-inferior to dalteparin in preventing VTE recurrence over a period of six months post-randomization. If non-inferiority is demonstrated, the study will further evaluate the potential superiority of abelacimab.

The trial will involve multiple study visits, beginning with an inclusion (screening) visit to confirm eligibility based on criteria such as age, cancer type, and recent VTE diagnosis. Participants must be at least 18 years old and have confirmed gastrointestinal or genitourinary cancer, with no intended curative surgery during the study. Eligible patients must have a confirmed symptomatic or incidental proximal lower limb deep vein thrombosis or pulmonary embolism and be indicated for anticoagulation therapy with low molecular weight heparin for at least six months. Written informed consent is required for participation.

Following the screening visit, participants will be randomized to receive either abelacimab or dalteparin, both administered via subcutaneous use. The trial will include regular follow-up visits to monitor the participants' health status, adherence to the treatment regimen, and any adverse events. The primary endpoint is the time to the first event of centrally adjudicated VTE recurrence within six months post-randomization. The study is expected to conclude with an end-of-study visit, where final assessments will be conducted.

The overall duration of the trial is estimated to be from April 2021 to September 2025, with each participant's involvement lasting approximately six months. Conditions that may lead to early termination from the study include withdrawal of consent, significant protocol deviations, or adverse events that compromise participant safety. The trial is not classified as low intervention and is conducted under the authorization of relevant regulatory bodies.

The clinical trial involves the administration of **Abelacimab**, a concentrate for solution for infusion, with a concentration of 150 mg/ml. This experimental medication is administered via **subcutaneous use**. The maximum daily dose is 150 mg, and the treatment period extends up to 6 months. Abelacimab is a protein-based biological product developed by Anthos Therapeutics Inc. The primary objective of the study is to evaluate the non-inferiority of Abelacimab compared to the comparator treatment in preventing venous thromboembolism (VTE) recurrence in patients with gastrointestinal or genitourinary cancer-associated VTE.

The comparator treatment in this study is **Fragmin® 5000 IU**, a solution for injection containing **Dalteparin Sodium**. This medication is also administered via subcutaneous use. The maximum daily dose for Fragmin is 18,000 IU, with a treatment duration of up to 6 months. Fragmin is a polymer-based biological product manufactured by Pfizer Limited. The study aims to compare the efficacy of Abelacimab against Fragmin in terms of VTE recurrence and bleeding outcomes.

The efficacy of the clinical trial will be assessed by evaluating the primary endpoint, which is the time to the first event of centrally adjudicated **venous thromboembolism (VTE)** recurrence within 6 months post-randomization. This endpoint will be used to determine whether the investigational product, abelacimab, is non-inferior to the comparator, dalteparin, in preventing VTE recurrence in patients with gastrointestinal or genitourinary cancer-associated VTE. If non-inferiority is established, the trial will further assess the potential superiority of abelacimab over dalteparin.