CNIPA Adjudged Chinese Patent of Crystal of Lenvatinib Was Invalid

April 30th, 2021, CNIPA (Chinese National Intellectual Property Administration) issued a re-examination decision, indicated that the patent of Crystal of Lenvatinib (Chinese patent filing No. 200480036184.1, which International publication No. WO2005/063713) should be invalid, because this patent possesses no creativity/inventive steps.

Lenvatinib is a c-Kit kinase inhibitor, produced by Japanese Eisai Company (Eisai R&D Management Co., Ltd.). Lenvatinib has been used for terminal thyroid cancer, terminal kidney cancer, and liver cancer.

For extending a monopoly period of breakthrough drugs, pharmaceutical enterprises, generally, file patent for the crystal of the drugs, after filing a patent for the drugs’ compound. However, the creativity requirement for crystal patents may be advanced by the patent examiner.