A drug patent invalidation case, represented by LUNG TIN LAW FIRM, was selected as one of the Top Ten Cases of Patent Reexamination and Invalidation in 2021

 

Today, the 22nd World Intellectual Property Day, China National Intellectual Property Administration released the Top Ten Cases of Patent Reexamination and Invalidation in 2021. The patent invalidation case of "Novel sulfamides and their use as endothelin receptor antagonists" patent was selected as a typical case in pharmaceutical compounds field. And this case was represented by the pharmaceutical and biological team of our firm, LUNG TIN LAW FIRM.

 

 

The patent involved involves a drug compound Macitentan, which is a cure for pulmonary hypertension and is included in the first list of drugs for rare diseases selected by the Ministry of Finance, the National Medical Products Administration and other departments. After representing the case, our team did a comprehensive analysis on the technical solutions of the patent involved, and thoroughly examined its family patents, series of applications, and priority documents. Then, our team filed 23 invalidation requests supported by evidences including the priority cannot be claimed, the insufficient disclosure of the compounds in the form, the unrecognized non-selective inhibitory effect on the A and B receptors, the inconsistent experimental data, and the lack of creativity, making the patentee to narrow the originally extremely broad Markush claims to two specific compounds. At the same time, judges of this case also made notice the drafting defects of the specification of the patent involved, specifically pointed out such defects and the potential risk to the patentee of such defects, and gave advice on the drafting of such patents.