BioWorld International Correspondent

PARIS - Cellectis SA has welcomed the decision of the Opposition Division of the European Patent Office to uphold its patent No. EP 419 621, which covers a gene-targeting process involving homologous recombination.

Cellectis, which is based in the Biocitech science and business park in the Paris suburb of Romainville, pointed out that and several other patents granted to the Institut Pasteur in Europe, Japan and the U.S. also have been maintained "despite the numerous oppositions lodged by Cellectis' competitors."

Cellectis holds exclusive rights to the Institut Pasteur patents, which cover all DNA integration processes, whether through the insertion of regulatory sequences that can modify the expression of an endogenous gene, or through the insertion of coding sequences for placing the desired protein in a defined recipient genomic location with the aim of obtaining a full and functional recombinant gene via the natural process of homologous recombination.

The company specializes in the development and production of custom meganucleases for in vivo DNA surgery and also provides tools for rational reverse genetics and targeted recombination. Cellectis' products induce site-directed, double-strand DNA breaks in living cells and can be used in a wide range of biotechnological and therapeutic applications.

"This decision reinforces our patent portfolio . . . and strengthens our position in the U.S., European and Japanese markets, where a growing number of players are seeking engineered cells and animals for their development activities," said David Sourdive, vice president of corporate development at Cellectis. "A major strength of our patent portfolio is that it enables the substitution of a mouse gene by a reporter gene or by its human counterpart - a process referred to as 'humanization,'" he added.

Cellectis pointed out that humanized mice generated from the Institut Pasteur's technology are being used throughout the pharmaceutical industry to validate drug targets, test the efficacy and safety of monoclonal antibodies, and develop high-affinity therapeutic antibodies. Leading biopharmaceutical companies such as AstraZeneca, GlaxoSmithKline, Genentech, Merck & Co, Pfizer, Shire, Deltagen, Lexicon, Regeneron and TransGenic utilize those technologies under sublicenses granted by Cellectis.