Chugai Seiyaku Bispecific Antibody Substitutes Coagulation Factor VIII
Summary
Chugai Seiyaku Kabushiki Kaisha filed patent application US20260109782A1 for bispecific antibodies that specifically bind to both Factor IX/Factor IXa and Factor X, functionally substituting for blood coagulation Factor VIIIa. The disclosed antibody A44/B26 reduced coagulation time by 50 seconds or more compared to untreated controls. The inventors further developed commonly shared light-chain antibodies using the L chain from antibody A44, demonstrating that A44L can serve as shared L chains for multispecific antibody constructs with appropriate CDR shuffling.
“Among these antibodies, the antibody A44/B26 reduced coagulation time by 50 seconds or more as compared to that observed when the antibody was not added.”
About this source
USPTO classification C07K covers peptides: short amino-acid chains that form the backbone of antibodies, hormones, vaccines, and increasingly a wider class of therapeutic modalities. Every newly published application in C07K lands in this feed, around 175 a month. Applications publish 18 months after filing, so this feed reveals what antibody engineering groups, vaccine developers, and plant biotech researchers were working on in the prior year and a half. Watch this if you compete in biologics, file freedom-to-operate analyses on antibody drug candidates, scout acquisition targets in vaccine platforms, or track protein-based agricultural biotech filings.
What changed
Chugai Seiyaku Kabushiki Kaisha filed USPTO patent application US20260109782A1 disclosing bispecific antibodies that bind to both Factor IX/Factor IXa and Factor X, functionally substituting for coagulation Factor VIIIa by promoting Factor X activation. The disclosed antibody combination A44/B26 reduced coagulation time by 50 seconds or more compared to untreated samples. The inventors also demonstrated that the light chain from antibody A44 (A44L) can serve as a commonly shared light chain for constructing multispecific antibodies with appropriate CDR shuffling.
Affected parties in the pharmaceutical and biotechnology sectors should note this patent filing for hemophilia therapeutics. While a patent application does not itself create regulatory obligations, it establishes intellectual property claims that could affect R&D programs in Factor VIII replacement therapies. Any entity developing bispecific antibodies targeting the Factor IX/Factor X activation pathway should conduct freedom-to-operate analyses.
Archived snapshot
Apr 23, 2026GovPing captured this document from the original source. If the source has since changed or been removed, this is the text as it existed at that time.
ANTIBODY SUBSTITUTING FOR FUNCTION OF BLOOD COAGULATION FACTOR VIII
Application US20260109782A1 Kind: A1 Apr 23, 2026
Assignee
Chugai Seiyaku Kabushiki Kaisha
Inventors
Kunihiro Hattori, Tetsuo Kojima, Hiroyuki Saito, Taro Miyazaki, Tetsuhiro Soeda
Abstract
The present inventors produced a variety of bispecific antibodies that specifically bind to both F. IX/F. IXa and F. X, and functionally substitute for F. VIIIa, i.e., have a cofactor function to promote F. X activation via F. IXa. Among these antibodies, the antibody A44/B26 reduced coagulation time by 50 seconds or more as compared to that observed when the antibody was not added. The present inventors produced a commonly shared L chain antibody from this antibody using L chains of A44, and showed that A44L can be used as commonly shared L chains, although the activity of the resulting antibody is reduced compared to the original antibody (A44HL-B26HL). Further, with appropriate CDR shuffling, the present inventors successfully produced highly active multispecific antibodies that functionally substitute for coagulation factor VIII.
CPC Classifications
C07K 16/36 C07K 16/00 C07K 16/40 C07K 16/468 C07K 2317/24 C07K 2317/31 C07K 2317/56 C07K 2317/622 C07K 2317/75
Filing Date
2025-12-17
Application No.
19423119
Mentioned entities
Parties
Related changes
Get daily alerts for USPTO Patent Applications - Peptides (C07K)
Daily digest delivered to your inbox.
Free. Unsubscribe anytime.
Source
About this page
Every important government, regulator, and court update from around the world. One place. Real-time. Free. Our mission
Source document text, dates, docket IDs, and authority are extracted directly from USPTO.
The summary, classification, recommended actions, deadlines, and penalty information are AI-generated from the original text and may contain errors. Always verify against the source document.
Classification
Who this affects
Taxonomy
Browse Categories
Get alerts for this source
We'll email you when USPTO Patent Applications - Peptides (C07K) publishes new changes.
Subscribed!
Optional. Filters your digest to exactly the updates that matter to you.