November 22, 2004

Anchen files ANDA for Wellbutrin XL (buproprion)

Anchen files ANDA for Wellbutrin XL (buproprion) Anchen files ANDA for Wellbutrin XL (buproprion) By Lawrence B. Ebert Taiwan-based generic company Anchen Pharmaceuticals has submitted an abbreviated new drug application (ANDA) to the FDA for Biovail's Wellbutrin XL (once daily dose of bupropion for depression). Litigation over bupropion has been extensive. Current issues are NOT about the drug itself (the composition of which is off patent) but about the formulations for controlled delivery of the drug. The Excel and Impax decisions of the Court of Appeals for the Federal Circuit have involved interpretation of the foreseeability prong of the US Supreme Court decision in Festo (535 US 722 (2002)). Wellbutrin is a drug used to treat depression, but the underlying chemical is also used for smoking cessation (marketed as ZYBAN). Of depression, the chemical is different from Paxil, Prozac and Zoloft, and as a result, Wellbutrin can often successfully treat people with depression whose condition has not improved from taking these other drugs. Although the chemical of Wellbutrin and Zyban has been off patent as a composition of matter for a long time, in 1995 Glaxo received a patent for the extended release formula of Wellbutrin SR. In 1999, generic drug manufacturer Andrx filed two ANDAs with the FDA seeking to sell generic versions of extended release Wellbutrin and Zyban. Andrx argued that because its generic used a different method of extended release, that it did not infringe on Glaxo's patent. Four other generic manufacturers followed Andrx's lead, and several have received tentative approval to manufacture and market their generic versions. In February of 2002, the US District Court for the Southern District of Florida ruled that Andrx did not violate Glaxo’s patent and therefore should be allowed to manufacture and market its generics. On appeal, however, the Federal Circuit Court of Appeals held that the district court in Florida erred in its construction of the patent infringement claims. Glaxo owns U.S. Patent No. 5,427,798 (the ’798 patent) directed to controlled sustained release tablets containing bupropion hydrochloride. Pharmacologically, bupropion (m-chloro--t-butylaminopropiophenone) is a monocyclic aminoketone antidepressant. See U.S. Patent No. 4,393,078 (issued July 12, 1983) (the ’078 patent). These compounds treat depression and inebriation. In addition, they facilitate the cessation of smoking by producing neural stimulation in mammalian systems. See ’798 patent, col. 1, ll. 5-10; ’078 patent, col. 1, ll. 29-39; U.S. Patent No. 3,819,706 (issued June 23, 1974). To avoid the need for multiple dosages with the attendant fluctuations in plasma bupropion concentrations, Glaxo invented a sustained release formulation of the compound. While bupropion hydrochloride itself was separately patented, Glaxo obtained the ’798 patent to protect its sustained release formulation of the drug. Glaxo markets this patented sustained release formulation as Wellbutrin®SR for treatment of depression and as Zyban® for smoking cessation. The key ingredient for achieving sustained release in this invention is hydroxypropyl methylcellulose (HPMC), which is a partly O-methylated and O-(2-hydroxypropylated) cellulose. In oral preparations, HPMC extends drug release by transforming into a gel that swells upon ingestion. The hydrogel state of HPMC releases bupropion hydrochloride from an ingested tablet over a period of time. The ’798 patent claims a sustained release tablet containing an admixture of bupropion hydrochloride and HPMC. However, many of the claims as originally filed did not recite HPMC as a limitation. During prosecution on the merits in the United States Patent and Trademark Office (Patent Office), the examiner rejected the claims that did not recite HPMC for lack of enablement under 35 U.S.C. § 112, 1. Glaxo amended those claims to overcome the rejection. The first independent claim of the ’798 patent states: 1. A controlled release tablet comprising 25 to 500 mg of bupropion hydrochloride and hydroxypropyl methylcellulose, the amount of hydroxypropyl methylcellulose to one part bupropion hydrochloride being 0.19 to 1.1 and said tablet having a surface to volume ratio of 3:1 to 25:1 cm-1 and said tablet having a shelf life of at least one year at 59deg to 77deg F. and 35 to 60% relative humidity, said tablet releasing between about 20 and 60 percent of bupropion hydrochloride in water in 1 hour, between about 50 and 90 percent in 4 hours and not less than about 75 percent less in 8 hours.

The WTO angle and TRIPS

The WTO angle and TRIPS: "The WTO angle and TRIPS By Lawrence B. Ebert Of the Ballmer quote: 'Someday, for all countries that are entering the [World Trade Organization], somebody will come and look for money owing to the rights for that intellectual property.' Section 5, Article 27, paragraph 1 of TRIPS recites: 1. Subject to the provisions of paragraphs 2 and 3, patents shall be available for any inventions, whether products or processes, in all fields of technology, provided that they are new, involve an inventive step and are capable of industrial application. (5) Subject to paragraph 4 of Article 65, paragraph 8 of Article 70 and paragraph 3 of this Article, patents shall be available and patent rights enjoyable without discrimination as to the place of invention, the field of technology and whether products are imported or locally produced. Paragraphs 2 and 3 don't say anything about business method or software patents. [http://www.wto.org/english/docs_e/legal_e/27-trips_04c_e.htm#5] David Berlind writes: Given the significant overlap between the members of the WTO and the European Union [EU], I'm having a tough time imagining how, if Europe can't uphold patents on software, the WTO can. One poster observed that the EU could take the position that business methods/software are not a 'field of technology' or perhaps even 'inventions.' Further, if the USA did even try to get WTO to force a change in the EPC, the EU would counter-attack with TRIPS complaints about various aspects of the US patent system which currently favour US-based inventors. --> Mutually assured standoff. Berlind also wrote of the WTO remark: 'the easiest way to get rid of a potential customer forever is to sue them. Especially when that customer is a government. Governments usually have pretty big budgets.' Within the US, patent holders have sued customers. Go back to the days of the Selden patent on the automobile. One of the advertising slogans for licensed cars was 'Don't buy a lawsuit.' Henry Ford said that this tactic by the Selden patent holder (ALM) launched Ford's business. In the pharma business today, many claims on drugs are written such that patients, doctors, and pharmacists could be sued for use of competitor's infringing drugs. For example, this could have happened with omeprazole. But, of course, it didn't. In the area of copyright, there have been some exemplary suits brought by the RIAA against consumer-infringers, but this is tricky business. A different website gives a different example. http://www.linuxworld.com.au/index.php/id;1874419189;fp;4;fpid;1 -->Up to now, not many users have faced such threats. When asked for an example of a user actually getting sued over intellectual property rights, Microsoft spokesmen go back four years. In 2000, Allan Konrad, a computer scientist, sued three dozen corporations, including General Motors, Ford Motor, The Boeing Co., Daimler Chrysler, United Air Lines and Eastman Kodak. Konrad held three patents and ownership to the mechanism of Web-based delivery of information. He went after corporations serving Web information from back-end databases. 'Microsoft worked to get IBM, Sun and AOL, whose products were also implicated, to step in collectively on behalf of our customers. We hired one law firm to defend them, paid the cost of that. The outcome was very positive, the infringement claims were thrown out,' said David Kaefer, director of business development at Microsoft. <--"

November 13, 2004

Navigating the patent maze: Nap Hal - Comments Addressed

Navigating the patent maze: Nap Hal - Comments Addressed: "Nap Hal - Comments Addressed An interested reader commented on the post in which I expressed approval for the decision of the Indian Government to not oppose the European Patent, now owned by Monsanto, that used Nap Hal. The reader raised several points that I would like to address. I also hope that it evokes more discussion on this topic area. (Sidebar - there are currently 5 parties opposing this patent, including Greepeace and the European Flour Milling Association) The reader raises several points. The first point, quoted below, speaks to whether the patent claims are in violation of the European Patent Convention. The Patent in question explicitly claims a wheat variety, and so is squarely in violation of the European Patent Convention.?? The short answer is that the patent in question (EP 0 445 929) does not claim any plant varieties. The claims are directed to soft-milling wheat with particular characteristecs, flour prepared from that wheat, dough or batter prepared from the flour, edible products made from the dough or batter, and biscuits made from the flour. The second point of the reader is that 'the disclosure of the patent shows that the genetic traits which are key to the patent (double null allele in glu-D1 gene) were wholly derived from the landrace developed in India, namely, Nap Hal.' I'm not sure what the reader's objection is other than the landrace came from India. In fact, the landrace was obtained from a public germplasm bank. The accession was placed prior to the Convention on Biological Diversity, so that treaty does not control the situation. Until the CBD, typically there were no restrictions on accessions or, in the case of the CGIAR the restrictions regarding intellectual protection placed on germplasm held in FAO Trust were limited to the variety itself and did not extend to derivatives (such as the wheat claimed in the Monsanto"