Wednesday, July 8, 2026

Patent intelligence · US

US 8143276

4-thio substituted quinoline and naphthyridine compounds

granted A61PA61P31/00
Status granted
Linked drugs 1
Pipeline programs 4
Years to expiry 6
Applicant portfolio 7
Patent details — US 8143276

Quick answer

US 8143276 (4-thio substituted quinoline and naphthyridine compounds) is held by XTL BIOPHARMACEUTICALS LTD.. Status: granted. Granted Mar 27, 2012. Expires Mar 22, 2032 (6 years remaining) — relevant for patent-cliff and LOE planning.

Key facts

Grant date
Expiration
Claims
18
CPC classes
A61P, A61P31/00

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Frequently asked questions

What is US patent 8143276?

US 8143276 (4-thio substituted quinoline and naphthyridine compounds) is held by XTL BIOPHARMACEUTICALS LTD.. Status: granted. Granted Mar 27, 2012. Expires Mar 22, 2032 (6 years remaining) — relevant for patent-cliff and LOE planning.

Who owns US 8143276?

XTL BIOPHARMACEUTICALS LTD. is listed as the applicant in USPTO PatentsView records indexed by NovaPharmaNews. We track 7 pharmaceutical patents for this assignee.

When does US 8143276 expire?

Our index shows an expiration date of Mar 22, 2032 (6 years from today). Confirm material dates against USPTO, FDA Orange Book, or qualified counsel before contractual decisions.