Chugai’s NXT007 Achieves No Bleeds, Favorable Safety in Hemophilia A Phase I/II Trial

Chugai Pharmaceutical announced initial clinical results from the Phase I/II NXTAGE trial of NXT007, its next-generation bispecific antibody for hemophilia A, at the 2025 International Society on Thrombosis and Haemostasis (ISTH) Congress. NXT007, which builds on the foundation of Hemlibra, is designed for subcutaneous use and aims to offer improved treatment options for patients with hemophilia A.

“We are very excited that this first data in people with hemophilia A, suggests that NXT007 has the potential to provide hemostatic normalization. Based on these data, we plan to initiate three Phase III studies of NXT007 next year, including a head-to-head study with Hemlibra. Treatment in hemophilia A has drastically evolved in recent years, and there are now expectations for treatments with even higher efficacy and even more convenient dosing form. Together with Roche, we will focus on the clinical development of NXT007, aiming to deliver it as a new treatment option as soon as possible to people who need it,” said Dr. Osamu Okuda, Chugai’s President and CEO.

The reported data came from Part B of the study, which included Hemlibra-naïve patients with severe hemophilia A aged 12 to under 65 years, without factor VIII (FVIII) inhibitors. Participants were divided into four dosage cohorts. Following an initial loading phase, they received maintenance doses of NXT007 every four weeks. Higher dose groups (B-3 and B-4) achieved plasma concentrations aligned with normal FVIII-equivalent activity, and notably, no treated bleeds were reported in these groups during the maintenance period.

NXT007 demonstrated a favorable safety and tolerability profile. The incidence of adverse events was not dose-dependent, and no serious adverse events or treatment-related withdrawals were observed. Importantly, no thromboembolic events occurred, reinforcing the potential of NXT007 as a promising advancement in the management of hemophilia A.