Lexicon Granted License to Cellectis' Homologous Recombination Technology

Lexicon Genetics Incorporated has announced that Cellectis SA has granted Lexicon an exclusive, worldwide license under the patents and patent applications covering Cellectis' technology for the specific replacement or insertion of a gene in a eukaryotic genome.

The license applies to the use of Cellectis' technology in combination with internal ribosome entry site ("IRES") or isogenic DNA technology in the generation of genetically-modified mice.

Cellectis' technology is frequently used to insert markers of gene expression or to generate mice in which the human counterpart to a mouse gene has been inserted, or "knocked in".

Lexicon already held a non-exclusive license under these patent rights, and has utilized this technology in the generation of knockout mice as a complement to Lexicon's suite of patented gene targeting technologies.

The license grants Lexicon exclusive rights to make, use, sell and import genetically-engineered mice generated using this technology in combination with IRES or isogenic DNA technology, subject to nonexclusive rights previously granted by Cellectis, with the exclusive right to grant sublicenses.

The term of the exclusive license is for the life of the patents. The technology is covered by United States patent numbers 6,528,313, 6,638,768 and 6,528,314 and related patents and patent applications in the United States and other countries.

Lexicon was granted an exclusive license under patents and patent applications covering IRES technology for genetically-modified mice from Stem Cell Sciences plc in November 2005.

IRES technology is commonly used to enhance the accuracy and versatility of gene expression in genetically-altered mice and cultured stem cells.

Lexicon obtained an exclusive license under the patent rights to isogenic DNA technology in 1996.

Lexicon's intellectual property estate now includes exclusive rights under 12 United States patents related to its gene targeting technologies.

"This is an important set of technologies for biotechnology and pharmaceutical companies using knockout mice as a component of their target and drug discovery efforts," said Lance Ishimoto, J.D., Ph.D., senior vice president of intellectual property at Lexicon.

"Our experience confirms the power of using this suite of technologies together in the generation and analysis of genetically-modified mice."