BMS sued Korean pharmaceutical companies alleging patent infringement of entecavir compound patent and low dose formulation patent

Baraclude tablets are a blockbuster drug of BMS that has been sold for the treatment of chronic hepatitis B virus infection in Korea. BMS listed 2 patents in Green List of KFDA that is a local version of the Orange Book of US FDA. Entecavir compound is the active ingredient of Baraclude.

Korean generic companies obtained MA for generic versions to Baraclude and are ready to launch their generic products to the local market. BMS filed patent infringement lawsuits against Korean pharmaceutical companies recently.

Before BMS patent infringement lawsuits, local companies filed invalidity trials to challenge the validity of the corresponding Korean entecavir compound patent. Also, they filed trials to confirm the scope of patent right about the corresponding Korean low dose formulation patent. The invalidity case of the compound patent is pending in the IPT of KIPO. But the IPT decided that generic products do not infringe the scope of the low dose formulation patent. In appeal, the Patent Court upheld the IPT decision that low dose entecavir formulations of 0.5mg or 1.0 mg should be regarded being obvious over the prior art and that generic drug do not infringe the subject patent.

Korea has the bifurcated system that allocates decision power to separate authorities. Patent infringement issue and patent invalidity issue must be decided by two separate and independent courts. Patent infringement and invalidity challenge may occur simultaneously but two proceedings are correlated.

In the patent infringement lawsuits, defendants Korean companies will raise an affirmative defense about invalidity of entecavir compound patent. Such invalidity defense is allowed and the court may stay the infringement lawsuit proceeding on its discretion until the IPT of KIPO decides validity issue.

On the other hand, defendants are quite safe from patent infringement liability of low dose formulation patent because they had prior decisions from the IPT and the Patent Court that their products are out of the scope of the patent claims in issue.

IPT Decided One of 2 Patents on Herceptin (trastuzumab) Listed in Green List of KFDA as being Invalid

Roche launched Herceptin for the treatment of HER2-positive metastatic breast cancer in Korea. And Celltrion, a Korean Pharmaceutical company, developed a biosimilar Herzuma to Herceptin (trastuzumab) and obtained marketing approval (MA) for a biosimilar Herzuma (trastuzumab) from KFDA on January 16, 2014. It has been approved for treatment of early and advanced (metastatic) HER2-positive metastatic breast cancer as well as advanced (metastatic) stomach cancer. Roche filed a patent infringement lawsuit against Celltrion.

Under the bifurcated system about patent invalidity challenge and patent infringement litigation, an invalidation trial against one of 2 listed Herceptin patents was filed to the IPT in KIPO rather than a court.  On May 28, 2014, the IPT decided that Korean Patent No. 1,261,749 on Herceptin is invalid due to obviousness. Korean Patent No. 1,261,749 with the expiry date of August 25, 2020 is based on PCT/US2000/023391 claiming the priority on US60/151,018 application.

The losing party, patentee, appealed the IPT decision to the Patent Court. 

Remicade v. Remsima - Trademark Dispute between J&J and Celltrion

Remicade is a monoclonal antibody to treat RA. This blockbuster biopharmaceutical product was developed and has been sold by Centocor that is one of J&J groups.

A Korean company Celltrion developed a biosimilar product to Remicade and obtained a Market Approval (MA) from KFDA in 2013. Further Celltrion filed an application on their biosimilar product to EMA and has been trying to obtain MA, too.

On the other hand, Celltrion filed Remsima as their trademark with KIPO. J&J opposed to the TM application but failed in opposition. And Celltrion succeeded to register Remsima as their trademark for their new biosimilar products.

J&J filed an invalidation trial to Remsima TM registration before the IPT within KIPO. But Celltrion prevailed on the IPT proceeding. The losing party J&J appealed against the IPT decision to the Korean Patent Court. The two subject trademarks in dispute are shown below.

On August 18, 2014, the Patent Court rejected J&J's appeal finally. The Patent Court held that Remsima TM registration shall be valid because Remsima is not similar to Remicade in their sounds, shapes and meanings. The losing party J&J may appeal to the Supreme Court again.

Reverse Payment Agreement violates Antitrust Law in Korea: the First case decision by the Korean Supreme Court for GSK v. KFTC case on Feb. 27, 2014

1. Background

GSK owned a Korean patent for ondansetron, antiemetic drug and sold with a tradename as Zofran. Dong-A Pharmaceutical Co. developed a generic version of ondansetron and received a cease and demand letter from GSK. Both parties started lawsuits but soon signed a settlement agreement and withdrew lawsuits.

2. Settlement of Patent Infringement Litigations

By a Sale & Supply Agreement for ondansetron between both parties, GSK granted Dong-A to sell the product to large sized hospitals. Instead, Dong-A shall neither make nor sell any competing medications including ondansetron to Zofran. GSK agreed to pay large amount of money to Dong-A by cash every year for 5 years. Further GSK promised to offer additional significant amount as incentive for high sales performance.

3. KFTC investigation and lawsuits

KFTC investigated GSK/Dong-A patent settlement case and decided that the settlement was a reverse payment agreement that violated the Antitrust Act of Korea. In particular, KFTC found them violating Art. 19 of the Monopoly Regulation and Fair Trade Act (MRFTA) and fined GSK about US$2 million and Dong-A US$1.5 million.

4. The Supreme Court Decision

GSK raised an appeal to KFTC's decision to the Seoul High Court but the court confirmed the KFTC decision. And GSK further appealed the case to the Supreme Court.

GSK argued that the settlement was within the scope of his patent right. As they pointed out, Art.59 of MRFTA (Korean version of antitrust law) has provision that “This Act shall not apply to any act which is deemed as a justifiable exercise of the right under the Copyright Act, the Patent Act, the Utility Model Act, the Design Protection Act or the Trademark Act.”

However, the Supreme Court rejected GSK's argument. The court opined that a settlement with reverse payment violates antitrust law if a patentee may maintain his monopoly by the reverse payment and thus affects adverse effect on fair and free competition in the related market. In the decision, the court suggested several factors in finding any violation or liability. Those can include the amounts of reverse payment to the opposing party and anticipated profit of the patent owner, patent litigation cost, time span and period for non-compete, etc.

On the other hand, the Seoul High Court stated in their decision that when the subject patent is obviously invalid or the competing party has not infringed the patent, any settlement with reverse payment shall be regarded as being anticompetitive and shall be violation of antitrust law.

Korea is scheduled to implement the patent and drug MA linkage system that is a Korean version of the Hatch-Waxman Act system from March 15, 2015. Under the new system, the first generic company may obtain 12-month market exclusivity. Such exclusivity may cause motives or incentives for reverse payments between the patent owner and the first generic. In order to avoid antitrust violation issue, accordingly, it is recommendable to closely review the first decision of the Supreme Court on the reverse payment case.

Patent Marketing Approval Linkage

The FTA between Korea and USA includes provisions regarding the patent drug market approval (MA) linkage. Pursuant to the KORUS FTA, Korea has to fully implement patent drug market approval linkage from March 15, 2015. The key changes are summarized below.

1. Green List – the Korean version of Orange Book

When a company of a new drug application (NDA) has obtained a drug market approval (MA) from KFDA, the NDA holder must list patent information in the patent list (“Green List”) of KFDA. The Green List is similar to the Orange Book in the U.S., but is not the same. The deadline to list is 30 days from the receipt date of MA.

Unlike the Orange Book in the U.S., a NDA holder must list patents with the claim-by-claim basis in the Green List. Therefore, an applicant must specify every claim that covers the approved drug product and further an applicant must submit detailed explanation between each claim and the approved drug to KFDA.

2. ANDA Applicant’s Certification regarding Listed Patents

Like the HWA, an applicant of a generic drug application (ANDA) must submit a certification regarding listed patents of Green List to KFDA. The patent certification is similar to those of HWA. For example, an ANDA applicant must file a Para. IV certification if he wants to launch a generic drug before the expiry date of listed patents. In such a certification, the generic drug applicant must provide a detailed statement demonstrating that the listed patent is invalid or that the generic drug does not infringe the listed patent.

3. Notice to an NDA holder and a Patentee

Like the HWA, an ANDA applicant with Para. IV certification must notify the fact that an application for generic drug approval has been filed and the filing date of the application to the product approval holder and patent owner within 7 days of the application filing date. The obligation to notice will apply to an ANDA applicant who will launch their product before the expiry date of term of the listed patent. Otherwise, this provision does not apply to generic applicants who intend to launch their drug after the expiration of the listed patent.

4. 12-Month Stay on Generic Drug Entry

Within 45 days from the receipt date of the notice, the Patentee may file: a patent infringement action or a scope confirmation trial before the Korea Intellectual Property Tribunal (KIPT) against the generic drug. Further, the patentee/NDA holder may request KFDA to take an action stay generic drug entry for 12 months from the receipt date of the notice from an ANDA applicant. Such stay shall y apply only once to each generic applicant.

5. First Generic's 12-Month Marketing Exclusivity

The first applicant may obtain first generic marketing exclusivity for 12 months over other generics. The first applicant for this marketing exclusivity means : (a) to be the first filer of ANDA application or skinny (paper) NDA applications that are similar to 505(b)(2) applications in USA; and (b) to be successful in obtaining an IPT decision or a court decision from challenging actions against listed patents including a scope confirmation trial or invalidation action. The actions must be filed before filing a generic approval application.

6. Forfeiture of 12-Month Marketing Exclusivity

The first generic's marketing exclusivity shall be forfeited if the ANDA applicant failed to obtain MA within 12 months from the filing date; or failed to launch generic within 2 months from the date that the generic may be marketed.

7. Substantial Differences from the HWA system of USA

The patent MA linkage system in Korea may share basic principle with the HWA system of the U.S. Upon reviewing the Bill to the Drug Act and the draft of KFDA regulations, however, we can find that many details will be quite different from those of HWA. In order to grasp practical implications, it is better to compare two systems in detail after the Korean version has been fixed. The FTA of Korea and U.S. set the deadline to implement a full system of patent MA linkage in Korea: March 15, 2015. Therefore, we will certainly have final versions of law provisions and regulations within this year. We will provide you with them when they are available.

Denied Patent Term Extension for Novartis' Exelon® Patch in Korea

Novartis' Exelon® Patch has been used to treat mild to moderate dementia of the Alzheimer's type and mild to moderate dementia associated with Parkinson's disease. The active ingredient is rivastigmine.

Novartis obtained the first MA for Exelon® Capsule and the second MA for Exelon® Patch in Korea. Exelon® Patch uses a new formulation that allows rivastigmine to be administered in a transdermal therapeutic system (TTS).

Novartis listed two patents in the Green List (http://medipatent.kfda.go.kr) of KFDA pursuant to the linkage system of patent and market approval. The first patent is Korean Patent No. 133,686 that claims chemical compounds including rivastigmine, its pharmaceutical use. The term of the compound patent expired on December 23, 2012. The second patent is Korean Patent No. 569,051 that claims inventions of TTS formulation. The second patent will expire on January 8, 2019.

Novartis has another patent in issue that claims rivastigmine compound for transdermal administration and compositions for them. The patent in issue is Korean Patent No. 121,596 that has actually lmost the same scope of protection that of the basic compound patent of Korean Patent No. 133,686. The background between two patents is somewhat complicated because Korean Patent No. 121,596 stems from transient measure in 1987.

The Patentee and NDA holder, Novartis filed a petition for patent term extension of the basic compound patent on April 23, 2012. In Korea, the patent term extension system was first introduced on July 1, 1987. Under the 1987 Act that applied to the patent in issue, a petition for patent term extension may be filed only during the last three (3) years of the original term of the patent. Upon filing a PTE request, the term of the subject patent shall be extended automatically and shall be terminated on the expiry date retroactively in case the petition has been denied.

KIPO denied Novartis’ petition. Novartis appealed to the Seoul Administrative Court. On September 26, 2013, the court rejected Novartis’ arguments and denied PTE for Exelon Patch patent. The Patentee and NDA holder, Novartis appealed the lower court decision to the Seoul High Court again. The current PTE system has been based on 1990 amendment and the first PTE regulations of 1987 are quite different from those of the current PTE regulations. The PTE regulations of 1987 that must applied to Exelon Patch case had much more narrow scope than those of the current regulations in subject patents and gourds for PTE. Exelon Patch falls in such unfortunate cases during transient period between 1987 and 1990.

Physicochemical Data Addition to the Specification during Prosecution

In general, the specification for a new chemical compound should describe physicochemical data of the claimed compound to such an extent that persons skilled in the art could clearly understand, recognize and reproduce the invention without any additional specific knowledge. However, as for addition of physicochemical data during prosecution, the Patent Court has somewhat differentiated a new compound invention from a new medicinal use invention. The Patent Court held that adding physicochemical data through an amendment does not constitute new matter if examples of a process for preparing claimed chemical compounds are described in detail in the specification. In principle, Korean patent practice requires that all patent applications for novel chemical compounds include physicochemical data in its original specification so as to confirm the production of the compounds. Physicochemical data refers to element analysis data, NMR data, melting point, boiling point, refraction rate, ultraviolet or infrared spectrum, viscosity, crystal type, color or the like. In case a specification fails to contain these data, the application was rejected on the grounds of (i) being an incomplete invention or (ii) failing to meet the description requirement.

The Patent Court decision is significant in that it somewhat relaxes the strict standard applied to all chemical compound inventions that are without physicochemical data. Here is an example. A patent application for novel chemical compounds was rejected by KIPO on the ground that the specification failed to meet the description requirement for a specification. In response, the applicant filed an amendment by incorporating physicochemical data on the claimed compounds, such as structural formulae, melting points and NMR data, into the specification. KIPO rejected the amendment on the ground that the incorporated physicochemical data constituted new matter. The issue was whether the physicochemical data later incorporated into the specification were essential to the confirmation of the production of the claimed compounds, in addition to the initial disclosure in the specification. The Patent Court found that the physicochemical data were not necessary since the production of the claimed compounds was confirmed from the initial disclosure based on the following: (1) chemical names and molecular formulae of substituents for the claimed compounds described in the specification can confirm structural formulae, molecular weights and chemical formulae of the claimed compounds; (2) the description "by crystallization" confirms that the compounds produced are in a solid state; and (3) reaction conditions and processes for preparing the claimed compounds are described in detail to be easily reproduced. The Patent Court has thus held that if the production of the claimed compounds can be adequately confirmed from the initial disclosure in the specification, adding such data to the specification does not constitute new matter.

Really Strict Description Requirement on Pharmacological Effect in Korea

In principle, the pharmacological effect should be described to such an extent that persons skilled in the art could clearly understand, recognize and reproduce the invention without any additional specific knowledge in the specification for a medicinal use invention at the filing stage. It is paramount to understand that under Korean patent practice the specification for pharmaceuticals or medicinal use inventions must quantitatively describe their pharmacological effects. The Korea Supreme Court specifically held that (1) if a pharmacological mechanism by which a certain pharmacological effect is provided has been clearly known, a simple description of the pharmacological effect would suffice; however, (2) in case such a pharmacological mechanism has not been known, the specification should include quantitative experimental data or the specific development of confirmation the pharmacological effect, i.e., when specific experiments were conducted, experimental methods, experimental results or the like, so that others could also confirm such a pharmacological effect.

For example, a new pharmaceutical composition with an enhanced anti-emetic effect in which the composition comprises two known anti-emetic agents, i.e., ondansetron and dexamethasone was claimed but the specification only described in connection with the pharmacological effect of the claimed composition that “the anti-emetic properties of one anti-emetic agent (i.e., ondansetron) are enhanced by administering with the second anti-emetic agent (i.e., dexamethasone).” No quantitative data supporting the enhanced effect was included in the original specification. The application was finally rejected on the ground that the specification violated the description requirement and that the claimed invention had not been completed.

Furthermore, it is not permitted to add quantitative pharmacological data to the specification through an amendment during prosecution. For example, there was a real case that an applicant submitted a declaration which was prepared before the application filing date, describing experimental data supporting the synergistic effect of the composition during the examination and trial proceedings. In that case, KIPO and the Patent Court did not allow the applicant to add data based on the ground that the addition of experimental data is new matter to the specification. Therefore, it is required to have such data or descriptions contained within the original specification at the filing stage.

Pfizer v. Hanmi re: Infringement Litigation on Viagra Trademark for Diamond Shape and Blue Color in Korea

Pfizer’s blockbuster drug, Viagra tablet has known worldwide for its blue color and diamond shape. Right after expiry of a compound patent in Korea, many Korean companies launched generic versions of Viagra in local market. Among them, in particular, Hanmi Pharmaceutical decided to adopt their product’s shape and color as similar as possible to the original drug Viagra. As a result, Hanmi’s generic pill has almost a carbon-copy design with blue color and diamond shape with round edges. Through such a good price and clever marketing strategy, Hanmi could take nearly half the market in about 5 months after Pfizer's patent lapsed.

As an anticipated course, Pfizer filed a trademark infringement lawsuit against Hanmi but lost the first instance case. Pfizer appealed to the Seoul High Court and won the second instance case. Hanmi appealed the case to the Supreme Court late last year.

Pfizer obtained a trademark registration for Viagra’s diamond shape with blue color on February 17, 2005. (Korean TM Reg. No. 608,773) Hanmi contended that any diamond shape and blue color for drug tablets is common or conventional and thus does not have distinctiveness. Also Hanmi’s products have their own Trademark on the surface of tablet and on their package. The package is totally different from Viagra’s.

Hanmi argued that there is no likelihood of confusion between Viagra and Hanmi’s generic drug because (1) two products have their own TMs respectively on product itself as well as its package; (2) the subject drug must be distributed through doctor’s careful prescription and pharmacist’s delivery; (3) Hanmi used the diamond shape and blue color as design elements for drug tablets; and (4) such a diamond shape with blue color has been applied to drug tablets conventionally.

The Seoul Central District Court agreed with Hanmi’s arguments. However, on October 17, 2013, the Seoul High Court reversed the lower court’s decision and held that Hanmi infringed Viagra’s registered TM in diamond shape and blue color. The High Court held that the diamond shape with blue color had become a famous TM and there is likelihood of confusion about source of products having the same shape and color even though they have further TM on their surfaces and packages.

Hanmi appealed the decision to the Supreme Court. The case is pending. Pfizer has not brought the second lawsuit for damage compensation yet.

Patent Term Extension (PTE) Based on MA for Drug Inventions in Korea

1. History of Changes

The patent term extension system was first introduced in Korea on July 1, 1987. Under the 1987 Act, a petition for patent term extension may be filed only during the last three (3) years of the original term of the patent. Under the new 1990 Act, however, a petition for patent term extension may be filed within three (3) months from the date of the approval and six (6) months prior to the expiration date. The current law is basically the same as that of 1990.

Some Changes to the current patent term extension system went into effect on April 3, 2013. The key change to the current system is limiting the number of PTE instances from multiple available chances to only one. Under the current PTE system in Korea, PTE may be available only to the "first" regulatory approval for "a new chemical entity."

2. Subject Patent and Procedures

A patent is eligible for term extension if the patent is related to an approved medicinal or agricultural product, if the patent was unable to be practiced after grant due to pharmaceutical or agricultural regulatory approval requirements. Such a patent should claim a compound, composition indicating use, process of manufacturing, formulation for (1) an invention relating to a drug which requires a product approval under the Pharmaceutical Affairs Act ("PAA"); or (2) an invention relating to an agrochemical which must be registered under the Agrochemical Management Act ("AMA"),

Only registered patentee may apply for patent term extension to KIPO. If the patent right is jointly owned, all the patentees must jointly apply for an extension of the term.

An application for patent term extension must be submitted within three months from the date of the approval under the PAA or from the date of the registration under the AMA. The application, however, may not be submitted less than six months prior to the expiration of the original patent term. Also, a petition for patent term extension may not be filed after the expiration of the patent term. An application for patent term extension should be supported with evidence to show the reason for the extension.

3. Period and Number of Patent Term Extensions

The term of a patent can be extended only once. In case a product approval (or registration) is sought for multiple patents, the term is extended for each patent. However, in case multiple product approvals (or registrations) are sought for a single patent, the term is extended only for the first approval (or registration).

Prior to the current law, even an approval for a combination product whose components had been previously approved by KFDA could be the basis for PTE. In addition, the approval for a second use of an approved drug could also be the basis for PTE, since the approval was regarded as the "first" approval for the new use. Further, in some cases, even an approval for a new formulation comprising an approved active ingredient could be the basis for PTE, if the new formulation was not simply different in the dose of the active ingredient but was a different administration form compared to the previously approved drug (e.g., injection vs. tablet). However, under the current PTE regulation, PTE may be available only to the "first" regulatory approval for "a new chemical entity."

The period of PTE shall be the total length of non-working time to obtain authorization or registration under provisions of the PAA or AMA to work a patented invention. For example, for drugs, the period commencing from either the approval of a protocol for clinical testing from the government authority after obtaining a conditional approval to manufacture for clinical testing or the date the patent is registered, whichever is later; to the date that the final approval to market.

The maximum patent term extension obtainable is five (5) years regardless of whether the actual period of non-working caused by the statutory requirements under the relevant Act exceeds five years.

4. Appeal to the IPT and the Patent Court

If an examiner of KIPO rejects the petition or application for patent term extension, the applicant or petitioner may appeal to the IPT of KIPO. The appeal must be filed within thirty days from the date a certified copy of the rejection is served to the applicant or his agent. On the other hand, a 3rd party may challenge PTE through Invalidation Trial at the IPT of KIPO. If a losing party in the IPT proceedings wants to appeal against the decision of IPT, the party may bring a lawsuit to revoke the IPT decision to the Patent Court within thirty days from the date of receiving the decision.

Patent and Drug Market Approval Linkage in Korea

The FTA between Korea and USA includes provisions regarding the patent drug market approval (MA) linkage. Pursuant to the KORUS FTA, Korea already amended the Drug Act and is preparing enactments of further necessary provisions in the Drug Act and the Patent Act in order to fully implement the FTA. The full system for patent drug market approval linkage will be implemented on March 15, 2015.

1. Green List – the Korean version of Orange Book

When a company of a new drug application (NDA) has obtained a drug market approval (MA) from KFDA, the NDA holder must list patent information in the patent list (“Green List”) of KFDA. The Green List is similar to the Orange Book in the U.S., but is not the same. The deadline to list is 30 days from the receipt date of MA.

Unlike the Orange Book in the U.S., a NDA holder must list patents with the claim-by-claim basis in the Green List. Therefore, an applicant must specify every claim that covers the approved drug product and further an applicant must submit detailed explanation between each claim and the approved drug to KFDA.

2. ANDA Applicant’s Certification on Listed Patents

Like the HWA, an applicant of a generic drug application (ANDA) must submit a certification regarding listed patents of Green List to KFDA. The patent certification is similar to those of HWA. For example, an ANDA applicant must file a Para. IV certification if he wants to launch a generic drug before the expiry date of listed patents. In such a certification, the generic drug applicant must provide a detailed statement demonstrating that the listed patent is invalid or that the generic drug does not infringe the listed patent.

3. Notice to the NDA holder and the Patentee

Like the HWA, an ANDA applicant with Para. IV certification must notify the fact that an application for generic drug approval has been filed and the filing date of the application to the product approval holder and patent owner within 7 days of the application filing date. The obligation to notice will apply to an ANDA applicant who will launch their product before the expiry date of term of the listed patent. Otherwise, this provision does not apply to generic applicants who intend to launch their drug after the expiration of the listed patent.

4. Others to be Decided this year

The patent MA linkage system in Korea may be similar to the HWA system of the U.S. We envision that details will be quite different from those of HWA. However, we don’t have concrete information yet because the current law just has portions of necessary provisions. The FTA of Korea and U.S. set the deadline to implement a whole system of patent MA linkage in Korea: March 15, 2015. Therefore, with certainty, we will have details for remaining items within this year. We will immediately post them when they are available.

Roche v. Celltrion re: Herceptin Patent Infringement Lawsuit over Biosimilar Herzuma

Celltrion, a Korean company developed a biosimilar Herzuma to Herceptin (trastuzumab) and obtained market approval (MA) for a biosimilar Herzuma (trastuzumab) from KFDA on January 16, 2014. It has been approved for treatment of early and advanced (metastatic) HER2-positive metastatic breast cancer as well as advanced (metastatic) stomach cancer.

Roche has marketed Herception for the treatment of HER2-positive metastatic breast cancer in 150 mg in Korea. However, for high strength of 440 mg, Roche obtained MA just January 26, 2014. Celltrion obtained MA of the first trastuzumab biosimilar for two strengths, 150 mg and 440 mg at the same time and will launch them soon.

Roche filed lawsuit against Celltrion alleging that Herzuma infringes Roche’s patents. More details will follow soon after they are available.

Menarini’s Priligy (Dapoxetine HCl) Use Patent held Not Valid as being Obvious

Menarini launched Priligy in Korea. Dapoxetine HCl is the active ingredient in Priligy tablets. Korean patent No. 719, 977 covers the branded products and is listed in Green List of KFDA. The patented invention is “Methods of Using Rapid-Onset Selective Serotonin Reuptake Inhibitors for Treating Sexual Dysfunction.” The patent at issue is not for a compound invention but for the second use invention. The Korean patent for the second use invention will expire on June 5, 2021. Several Korean generic companies filed invalidity proceedings to challenge the second use patent. Menarini will face generic companies’ challenges soon.

On August 23, 2013, the IPT of KIPO held that the patent in issue is not valid because the compound and its use have been disclosed in the prior art. There has been no challenge to the compound patent so far. The key issue for the second use patent was a new limitation of “on as as-needed basis” in claim language. The patentee argued that such a new limitation was not found in the prior art and made the claimed use invention being novel and nonobvious over the prior art. However, the IPT rejected the argument on the ground that such limitation is related to a method of administering a drug and thus such limitation may not be regarded as an element for a patent claim under Korean patent law.

The patentee appealed the IPT decision to the Patent Court and the case is pending.

Low Dose Entecavir Formulation in Korean Patent held as being Obvious by the IPT of KIPO

Entecavir is the active ingredient in Baraclude tablets of BMS. The drug has been sold for the treatment of chronic hepatitis B virus infection in Korea. When Korean generic companies noticed that a US district court found that entecavir would have been obvious in light of the prior art, they filed an invalidity trial to challenge the validity of the corresponding Korean compound patent, too. The invalidity case is pending in the IPT of KIPO.

On the other hand, Baraclude is covered by another patent for low dose formulation of entecavir. Several companies including those want to launch generic versions of Baraclude after expiry of extecavir compound patent, filed separate proceedings to challenge non-obviousness of law dose formulation over the prior art. The subject Korean patent is No. 757,155 that claims low dose entecavir formulations of 0.5mg or 1.0 mg for the treatment of chronic hepatitis B virus infection. The prior art discloses enetcavir compound, its use, a range of doses and animal test data, but did not disclose claimed doses.

On April 30, 2013, the IPT held that low dose entecavir formulations of 0.5mg or 1.0 mg should be regarded being obvious over the prior art. To the IPT decision, the patentee BMS appealed to the Patent Court and argued that a person of ordinary skill could have neither anticipated nor determined the claimed low dose formulations of 0.5mg or 1.0 mg entecavir from the prior art. Oral hearings were held two days for expert witness examination and BMS’s expert argued at the Patent Court that determining specific doses for human required numerous trials. The panel of 3 judges in the Patent Court will decide the case on March 14, 2014.

Pfizer’s Victory in Lyrica® Patent Infringement Lawsuit in Korea

Based on Pfizer’s Lyrica patent, Korean courts granted preliminary injunctions for patent infringement against two Korean pharmaceutical companies. The local companies launched a generic version of Lyrica last year. The active ingredient of Lyrica is pregabalin that is a known chemical compound and a derivative of GABA (gamma-aminobutyirc acid). Further, the pharmacological effect of pregabalin is known as a depressive neurotransmitter and has been sold as an anti-convulgent drug for a long time. Pfizer discovered a new medicinal use of pregabalin. The subject Korean Patent No. 491282 is directed to a new use of pregabalin for treating pain. It is a second use invention that is one of the main indications of Lyrica.

Korean companies challenged validity of the subject patent on the ground that the new use of pregabalin for treating pain can be anticipated or is obvious over the prior art. They alleged that the pain killing effect might be in the scope of anticipation of an ordinary skilled person because the prior art discloses the compound and its neurotransmitter depressing effect. Also, the blocking of certain neurotransmitter flow may be correlated with anti-pain effect. The IPT of KIPO and the Patent Court, however, maintained the patent by rejecting non-obviousness challenge. The invalidity proceeding has been reviewed by a separate authority rather than a civil court under bifurcation system and is pending before the Supreme Court as a final stage now.

In the meantime, the patentee brought lawsuit for seeking preliminary injunctions against generic companies before the Seoul Central District Court. Recently Pfizer won the cases and was successful in blocking selling generic version of Lyrica in Korea.

Data Exclusivity (DE) in Korea

In pharmaceutical industry, data exclusivity (DE) is an important IP right. DE is to protect the value of extensive pre-clinical and clinical data that establish a drug’s safety and efficacy, clinical indications and uses.

KFDA provides such DE through PMS (Post Marketing Surveillance) system. Before the expiry of PMS period, no generic drug is allowed to market. During PMS period, third parties cannot obtain approval for generic versions of the same product unless they can submit data that are (1) different from the data submitted for the first approval; and (2) equivalent to or exceeds the scope of data submitted for the first approval. There is no real case to obtain before expiry of PMS in Korea so far. Therefore, such PMS system has played an effective Data Exclusivity for drug developers.

Two categories of DE exist as follows:

1. New Drug – 6 years from marketing

    A. New Chemical Entity (NCE)
    B. Ethical Drugs different from already licensed drugs in terms of active ingredients or mixture ratios
    C. Ethical Drugs different from already licensed ones in the route of administration, while containing the same active ingredients

2. Improvement Drug – 4 years from marketing

    A. Ethical drugs which are identical to already licensed drugs in terms of active ingredients and route of administration but distinctively different in added indications.
    B. Ethical drugs which are modification of the structure, formulation, or indication of existing drugs. It is generally an improved version of the original drug in terms of safety, efficacy or convenience.