AB2 Bio has received a $30 million payment after Nippon Shinyaku exercised its option for exclusive U.S. commercialization rights to Tadekinig alfa in a rare pediatric hyperinflammatory disease.
The agreement covers Tadekinig alfa for Primary Monogenic IL-18-Driven Hyperinflammatory Syndrome in patients with NLRC4 and XIAP mutations. The ultra-rare and potentially life-threatening condition primarily affects infants and young children, and there are currently no FDA-approved treatments.
In addition to the $30 million option exercise payment, AB2 Bio is eligible to receive up to $100 million in development milestones and up to $500 million in commercial milestones and royalty payments. The company previously received a $6 million option fee under the companies’ 2025 option and license agreement.
Nippon Shinyaku now holds exclusive U.S. commercialization rights for the licensed indication. AB2 Bio retains U.S. rights to Tadekinig alfa for all other indications and worldwide rights outside the United States, including for the lead indication.
AB2 Bio will continue leading preparation of the Biologics License Application and other U.S. regulatory activities. The transaction may require clearance under the Hart-Scott-Rodino Antitrust Improvements Act, depending on the circumstances when the option is exercised.
Tadekinig alfa is a recombinant human interleukin-18 binding protein designed to neutralize excess free IL-18, which is a key driver of hyperinflammation. By restoring the balance between IL-18 and its natural inhibitor, the investigational therapy is intended to address the underlying disease mechanism rather than only treating symptoms.
AB2 Bio has completed its Phase 3 clinical program in the lead indication and demonstrated clinical proof of concept in three additional life-threatening orphan diseases.
The therapy has received Orphan Drug Designation in the United States and Europe, along with Breakthrough Therapy and Rare Pediatric Disease designations from the FDA. It may also qualify for a Priority Review Voucher if approved.
Patients with NLRC4 or XIAP mutations can develop severely elevated levels of free IL-18, leading to systemic hyperinflammation, multiorgan dysfunction, permanent organ damage and, in the most severe cases, death.
The Phase 3 program enrolled patients with genetically confirmed mutations who continued experiencing severe hyperinflammation despite receiving standard supportive care.
KEY QUOTES:
“This progress represents an important milestone for AB2 Bio and, more importantly, for patients and families affected by this devastating disease. Nippon Shinyaku’s decision reflects the strength of our clinical program and our shared confidence in Tadekinig alfa. Together, we are well positioned to accelerate the delivery of this potential therapy to patients in the United States.”
Dr. Djordje Filipovic, CEO of AB2 Bio
“AB2 Bio has established a leading position in the development of therapies targeting IL-18-driven diseases. There are currently no FDA-approved therapies for this rare and potentially life-threatening disease. We are pleased to expand our partnership with AB2 Bio and look forward to bringing Tadekinig alfa to patients in the United States.”
Dr. Toru Nakai, President and Representative Director of Nippon Shinyaku
“This agreement validates Tadekinig alfa’s clinical development program and underscores the strength of AB2 Bio’s long-term strategy. By combining our leadership in IL-18 biology with Nippon Shinyaku’s proven rare disease expertise, we are accelerating the path to patients while preserving significant long-term value through our retained global rights and the continued development of Tadekinig alfa across additional IL-18-driven indications.”
Dr. Andrea Pfeifer, Chair of AB2 Bio
