US patent granted for IMP731 antibody

The United States Patent and Trademark Office has granted a patent for the IMP731 antibody, owned by Australian biotech company Prima BioMed (ASX:PRR).

The antibody was originally developed by Immutep, before the immuno-oncology company was acquired by Prima in 2014. The new patent provides protection for specific sequences of the antibody and its use in depleting LAG-3+ T-cells by complement dependent cytotoxicity (CDC) and antibody-dependent cell cytotoxicity (ADCC).

Immutep in 2010 granted rights for the development of the antibody to GSK, which last year commenced first-in-human clinical trials of its own proprietary antibody (GSK2831781), derived from IMP731, for the treatment of autoimmune diseases. IMP731 and GSK2831781 are designed to specifically deplete potentially pathogenic, recently activated, LAG-3 expressing T-cells which are enriched at the disease site in T-cell driven immunoinflammatory disorders and should spare other T-cells which may be necessary for other functions.

Under the terms of the 2010 agreement, GSK has responsibility for all development and associated costs for GSK2831781. Prima BioMed may receive payments and potential milestones totalling up to £64 million and is eligible for single-digit, tiered royalties if all objectives are achieved.

Prima BioMed (ASX:PRR) shares were trading 6.67% higher at $0.048 as of around 1 pm on Thursday.