Hepatitis C Inhibitor Compounds

Boehringer Ingelheim Int. v. the Patent Reexamination Board- Admission of Post-Filing Experimental Data and the Binding Effect of Examination Result in Other Countries (Reexamination Decision No. 48444 by the Patent Reexamination Board on December 18, 2012)

Experimental data is vital to the patentability requirements of inventiveness, support, and enablement for chemical/medical application. During the substantive examination, the applicant may intend to supplement experimental data to support inventiveness after filing, which is called "post-filing experimental data". It is controversial whether post-filing experimental data shall be admitted. This article discusses admission of post-filing experimental data, as well as the binding effect of examination result in other countries based on analysis on an actual case.

This case is regarding a patent application with App. No. 200480013783.1 titled "Hepatitis C Inhibitor Compounds" where claim 1 relates to "a racemate, diastereoisomer, or optical isomer of a compound of formula (I)or a pharmaceutically acceptable salt or ester thereof". The applicant is Boehringer Ingelheim Int. ("Boehringer Ingelheim" hereinafter).

The patent application was rejected during the substantive examination for lack of inventiveness. The examiner holds that there is teaching in D1 regarding the compounds of Claim 1 and it is obvious for a skilled person to obtain the compounds of Claim 1 based on D1.

Not satisfied with the Rejection Decision, Boehringer Ingelheim filed a request for reexamination with the Patent Reexamination Board (PRB), submitted amended claims and comparative experimental data. Moreover, it argues that the patent application had been granted by the EPO.

The PRB issued an Notification of Reexamination and stated that: (i) the amended Claim 1 still possess no inventive step in view of D1; (ii) the post-filing experimental data should not be admitted because the experimental protocols and the data are not described in the original specification; (iii) the examination result in other countries is not binding on the examination in China.

In response to the Notification of Reexamination, Boehringer Ingelheim made further amendment to limit the compounds of formula (I) into four specific compounds, and highlighted the un-expectable technical effects achieved by the claimed compounds in terms of oral bioavailability etc., which can be supported by the post-filing experimental data.

After review, the PRB rendered the Re-examination Decision, rejecting on the grounds that: (i) the amended claim 1 lacks inventiveness in view of D1; (ii) the post-filing experimental data is still not admitted . Specifically, the PRB emphasized that the post-filing experimental data shall not be admitted unless the post-filing experimental data is used to support the effects that have already been explicitly described in the original specification with corresponding experimental data. In this case, there is no experimental data to support the technical effects described in the original specification. Thus, these described effects should be regarded as "assertive conclusion" and not regarded as real unexpectable technical effect. Meanwhile, the protocols for the post-filing experiment and its data are not described in the original specification.

Based on the above, the PRB upheld the Rejection Decision.

Remarks

(I) Provision regarding supplementing post-filing experimental data inGuidelines for Patent Examinationas well as its current development.

Guidelines for Patent Examination (2001 Edition) states that: the following additions are not allowable: (6)the experimental data is added to illustrate the advantageous effects of the invention, and/or the specific mode for carrying out the invention or embodiment is added to prove that the invention can be carried out in the extent of protection claimed in the claims (however, these supplementary information may be placed into the records of the application, for the examiner's reference to examine novelty, inventiveness and practical applicability). It further provided for the examination of invention applications in the field of chemistry where the applicant shall not be permitted to introduce the post-filing example, especially those involving the protection scope of the application, into the specification, let alone into claims. The supplementary experimental data may be placed into the records of the application, for the examiner's reference to examine novelty, inventiveness, and practical applicability.

Those contents within the parentheses and for the examination of chemical inventions were deleted from the Guidelines for Patent Examination (2006 Edition). The new amendment provided that "whether the description is sufficiently disclosed is judged on the basis of the disclosure contained in the initial description and claims, any embodiment and experimental data submitted after the date of filing shall not be taken into consideration". In other words, it explicitly stated that post-filing experimental data shall not be admitted in the examination of sufficient disclosure. However, it is not clear about the weight of post-filing experimental data in the examination of inventiveness.

Guidelines for Patent Examination (2010 Edition) is consistent with the 2006 Edition, which retains the regulations on post-filing experimental data for the examination of sufficient disclosure, but still does not provide clear provision on the weight of post-filing experimental data in the examination of inventiveness.

We noticed that in December 05, 2013, Chinese President XI Jinping and U.S. President Barack Obama issued the "Joint Fact Sheet on Strengthening U.S.-China Economic Relations," which states that "China affirms that the Chinese Patent Examination Guidelines permit patent applicants to file additional data after filing their patent applications, and that the Guidelines are subject to Article 84 of the Law on Legislation, to ensure that pharmaceutical inventions receive patent protection. China affirms that this interpretation is currently in effect." This sentence may be interpreted as not only does the post-filing data relates to patent protection, but also the interest and market development of multinational pharmaceutical companies in China. How will the Joint Fact Sheet affect the Chinese patent examination remains as an open question.

(II) Advice

In this case, the PRB clearly indicates that "the post-filing experimental data shall not be admitted unless the post-filing experimental data is used to support the effects that have already been explicitly described in the original specification with corresponding experimental data." Furthermore, in another famous case decided by the Supreme People's Court (SPC) on August 3, 2012, the SPC held that "when the applicant or patentee intends to submit comparative experimental date for proving the inventiveness of the claimed technical solution in view of the prior art, the data could be admissible with the proviso that the technical effects to be proved shall have already been described in the original application."

With respect to the subject case, the post-filing experimental data cannot be admitted for the reason that the surprising technical effects such as oral bioavailability are not described in the original specification.

As can be seen, an admissible post-filing experimental data must be submitted for the technical effects that have been explicitly described in the specification. Furthermore, there should be some corresponding data relating to the technical effects, avoiding that the described effects may be regarded as "assertive conclusion."

In order to acquire a stable and effective patent right, an applicant in the field of chemistry should make adequate preparation and rational arrangement. When some experimental data has been obtained proving the technical effects of claimed solution, these data should be selectively revealed in the original application. Especially for the beneficial effects in view of the prior art, it should be noted that both effects and corresponding supporting data should be provided in the original application. However, in some instances such as competitive industry and possible divulging of the invention before the filing date, the applicant may file a first application to take the initiative. In that case, the applicant should conduct preliminary experiments to obtain gross prediction about the technical effects of claimed solution, taking the key factors such as enablement and inventiveness into consideration. Since the preliminary experiments and the technical effects are described in the original specification, the applicant may try to "post-file" sufficient experimental data to support the arguments in case of a challenge during the examination of the application.

In addition, this case also shows that a Chinese patent application is examined in accordance with the Chinese Patent Law, the Implementing Regulations of the Chinese Patent Law, and the Guidelines for Patent Examination. The examination result in other countries would not be binding on the examination in the State Intellectual Property Office. Such result can only be provided for reference.

In summary, an applicant in the field of chemistry should pay more attention to the disclosure of experimental data and the technical effects of claimed solution in the original description, in order to acquire a stable and effective patent right.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.