Under the terms of the agreement, Spero will receive exclusive global rights, excluding Greater China, to develop, research, manufacture, and commercialize IBI355 (Spero R&D code: SP001)
Innovent will receive an upfront payment, and is eligible to receive development, regulatory and commercial milestone payments, totaling approximately US$1.1 billion, as well as tiered royalties on net sales
Spero plans to initiate a Phase 2 trial for IBI355 in Q2 2027 in IgG4-related disease (IgG4-RD), a serious, chronic fibroinflammatory condition with significant treatment burden and limited therapeutic options
Innovent plans to initiate a Phase 2 trial in China by early 2027 for Sjögren's disease (SjD), a chronic autoimmune disorder with limited therapeutic options
SAN FRANCISCO, CAMBRIDGE, Mass., and SUZHOU, China, July 14, 2026 /PRNewswire/ -- Innovent Biologics, Inc. (01801.HK) and Spero Therapeutics, Inc. (Nasdaq: SPRO) today announced an exclusive license agreement for IBI355 (Spero R&D code: SP001), a third-generation Fc-silent anti-CD40L antibody. Spero will receive exclusive rights to develop, research, manufacture, and commercialize IBI355 worldwide, excluding Greater China, where Innovent retains rights. Spero currently expects to advance IBI355 into a Phase 2 study in IgG4-RD patients in Q2 2027; Innovent expects to initiate a Phase 2 trial in China for SjD by early 2027.
IBI355 (SP001) targets CD40L, an immune signal protein that sits upstream of multiple immune pathways and has the potential to redefine treatment paradigms across a range of immune-mediated diseases. Innovent has evaluated this antibody in two healthy volunteer Phase 1 trials: a single ascending dose (SAD) study and a multiple ascending dose (MAD) study. Innovent has also evaluated IBI355 in a Phase 1b MAD study in patients with SjD. Data from the Phase 1b SjD study were presented in a poster session at the EULAR 2026 Congress.
"CD40L is an important upstream mediator of immune activation and T-cell/B-cell collaboration, both of which are relevant to IgG4-RD progression," said Dr. Arezou Khosroshahi, MD, Professor of Medicine, Emory University School of Medicine. "A non-B cell depleting approach that interrupts CD40L signaling could represent an important area for clinical evaluation in IgG4-RD, where patients need additional options that address chronic inflammation, relapse, and treatment burden."
"IgG4-related disease, Sjögren's disease, and other autoimmune conditions impose significant burdens on patients worldwide, with many facing limited treatment options." said Dr. Lei Qian, Chief R&D Officer (General Biomedicine) of Innovent Biologics. "We are pleased to partner with Spero Therapeutics on IBI355 to advance the development of this CD40L-targeted approach. By combining Innovent and Spero's immunology expertise and development commitment, we aim to accelerate the delivery of differentiated therapies to patients living with these chronic conditions. Our shared goal is to bring meaningful new options to patients in need, wherever they are."