Sanofi announced positive topline results from the global ElevAATe Phase 2 study, showing that efdoralprin alfa (formerly INBRX-101) met all primary and key secondary endpoints in adults with alpha-1 antitrypsin deficiency (AATD) emphysema, a rare genetic lung disease.

Efdoralprin alfa, an investigational recombinant human alpha-1 antitrypsin (AAT)-Fc fusion protein, demonstrated statistically significant superiority to the current standard of care, plasma-derived augmentation therapy.

When administered every three weeks (Q3W) or every four weeks (Q4W), efdoralprin alfa produced a greater mean increase in functional AAT levels within the normal range, as measured by trough concentrations at steady state at week 32 (p<0.0001). The study also met key secondary endpoints, showing a superior mean increase in average functional AAT concentrations and a higher percentage of days above the lower limit of the normal range across both dosing regimens.

Efdoralprin Alfa was well tolerated, with a safety profile comparable to plasma-derived therapy. Additional safety follow-up will continue in the ongoing ElevAATe OLE Phase 2 study.

“These data demonstrate that efdoralprin alfa achieved consistently higher functional AAT levels with less frequent dosing compared to the current standard of care,” said Christopher Corsico, Global Head of Development at Sanofi. “Maintaining protective protein levels is fundamental to managing AATD-related pulmonary disease, yet existing treatments require weekly infusions. The ElevAATe results reinforce the potential of efdoralprin alfa to become the first restorative recombinant therapy for AATD, reflecting our continued commitment to address serious unmet needs in rare and respiratory diseases.”

“AATD is a debilitating condition that remains difficult to manage,” said Igor Barjaktarevic, MD, PhD, Associate Professor at the David Geffen School of Medicine at UCLA and principal investigator for the ElevAATe Phase 2 study. “Achieving and maintaining normal AAT levels with less frequent dosing and without reliance on plasma donations would mark a significant advance for patients. Current therapies can restore but not sustain normal protein levels between infusions. I am encouraged by the ElevAATe trial results and the potential of efdoralprin alfa to transform treatment for people living with AATD.”

Efdoralprin Alfa has been granted Fast Track and Orphan Drug Designation by the U.S. Food and Drug Administration (FDA) for the treatment of AATD emphysema. The therapy remains under clinical investigation, and its safety and efficacy have not yet been evaluated by any regulatory authority. Sanofi plans to present the full Phase 2 data at an upcoming medical meeting and will engage with global regulatory agencies to determine next steps in development.