Pharmaceutical Industry Patent Challenge Cases

What is the patent challenge system?

This concept first came from the United States and originated from the Drug Price Competition and Patent Term Restoration Act (also known as the Hatch-Waxman Act) promulgated on September 24, 1984. According to Hatch-Waxman Act, generic drug manufacturers must submit one of the following four statements in accordance with the provisions of the Orange Book when submitting ANDA:

Paragraph I statement (PI): The drug is not patented;

Paragraph II statement (PII): The drug has a patent, but the patent has expired;

Paragraph III Statement (PIII): FDA is not required to approve the generic drug before the relevant patent expires;

Paragraph IV Statement (PIV): The patent relating to the generic drug being applied for is invalid or the generic drug is not infringing.

Among them, the ANDA declared by PIV is a typical generic drug challenge patent, and the PIV statement is a challenge. The first generic drug applicant to submit ANDA to FDA and contain PIV declaration, if the patent challenge is successful, FDA will give 180 days of market monopoly period. During these 180 days, FDA will no longer approve other ANDA holders to be listed, while generic drug enterprises that have obtained the market monopoly period can sell on the market at 60%-90% of the price of the original research drug, to cover the litigation costs it consumes in the event of a patent challenge and to quickly recover costs.

In China, patent challenges are accepted by the Patent Reexamination Board of the State Intellectual Property Office of China, and all patents are challenged by the public, including pharmaceutical patents. A patent can be challenged on a variety of grounds, for example: a pharmaceutical product or its production process does not meet the patentable standards of the country-novelty, inventive step or industrial applicability.

Domestic Patent Challenge Case-Sofebue

In December 2017, MSF submitted a challenge to the patent application for sofosbuvir (Sofosbuvir)/vipatavir composition, which is a third-party opinion before patent authorization. This patent challenge for vipatavir compound alone is an invalid request after patent authorization. The two are respectively based on Article 48 of the Implementing Rules of the the People's Republic of China Patent Law, "From the date of publication of the invention patent application to the date of publication of the patent grant, any person may submit an opinion to the Patent Office on a patent application that does not comply with the provisions of the Patent Law, with reasons." and prc patent law "article 45 since the date of the announcement of the grant of the patent right by the patent administration department under the state council, any unit or individual who considers that the grant of the said patent right does not conform to the relevant provisions of this law may request the patent reexamination board to declare the said patent right invalid.".

Since there are usually multiple patents around the same drug, including compounds, crystal forms, dosage forms, compositions, etc., the challenge of a patent is not enough to remove these unreasonable patent obstacles. For hepatitis C drugs with sofosbuvir as the core, there have been successful patent challenges in China before. For example, in 2014, an international non-profit organization I-MAK challenged the patent application for sofosbuvir prodrug in China (CN101918425A/ CN 200880018024.2), resulting in the patent being refused authorization in China. In April 2017, I-MAK submitted another invalid request for sofosbuvir compound patent. In 2016 and 2018, the National Patent Office separately rejected patent applications for a crystal of sofosbuvir (CN102858790A/CN 201180017181.3) and another prodrug (CN104402955A/CN 201410569402.3). In December 2017, MSF opposed the patent application for sofosbuvir/vipatavir composition (CN105517540A/ CN 201480047195.3) by submitting a third-party opinion.

These efforts aim to eliminate unreasonable patents around sofosbuvir, so that generic drug manufacturers can produce and compete in the market without barriers locally, and foreign generic drugs can also be imported and registered, thereby reducing drug prices and allowing more patients to access treatment.

Domestic Patent Challenge Case-Riximab

In April 2018, the Patent Reexamination Board made an invalidation review decision No. 35201, declaring Biogen IDEC Company (Baijian) No. 200510062686.8 invention patent "B-cell lymphoma combination therapy including administration of anti-CD20 antibody" (Patent No. 686) invalid. The chemical method involved in the patent is CHOP and the antibody is Rituximab (rituximab). Rituximab is an anti-CD20 human-mouse chimeric monoclonal antibody jointly developed by Roche and Bijian, which is mainly used in non-Hodgkin's lymphoma, chronic lymphocytic leukemia and rheumatoid arthritis.

The applicant for this invalidation is Shanghai Fuhong Hanlin. At present, the rituximab injections listed in China are all produced by Roche Pharmaceuticals. Fuhong Hanlin, Cinda Biology and Shenzhou Cell Engineering have entered Phase III clinical trials. Among them, the CD20 target rituximab similar drugs of compound Hanlin are to be included in the priority review. All patents 686 are invalid, which means that the listing process of rituximab similar drugs of Fuhong Hanlin and other companies will be accelerated.

Patent Challenges in Other Countries

The international community agreed to allow national laws to establish appropriate procedures to challenge unreasonable drug patents and patent applications that endanger public health and public access to drugs.

In 2017, MSF filed patent invalidation applications for sofosbuvir compounds at the European Patent Office; filed patent challenges for pneumococcal conjugate vaccine (PCV) in India; filed patent invalidation applications for PCV in South Korea; and supported other civil society organizations in India and Brazil to file patent challenges, mainly for HIV and hepatitis C drugs.