Показано, что продление патентной защиты противовирусного препарата дарунавир путём повторного его патентования в форме дарунавира этанолата незаконно. Проведен анализ формулы изобретения повторного патента ««Псевдополиморфные формы ингибитора ВИЧ-протеазы» WO 2003106461 A2», и показана её несостоятельность, как с научной, так и с этической точки зрения. Установлено, что первоначально дарунавир изучался в форме его этанолята. Дарунавир является одним из лучших ингибиторов протеазы вирусов иммунодефицита человека (ВИЧ) обоих типов. В настоящее время, в качестве активных фармацевтических субстанций, имеющих МНН дарунавир, используют не только дарунавира этанолят, но и дарунавир аморфный (несольватированный). Этот факт подтвержден результатами рентгенодифракционного исследования. Приведены основания для прекращения действия в РФ этого патента в установленном законом порядке.

It is shown that prolongation of patent protection for the antiviral drug darunavir by patenting it again as darunavir ethanolate is illegal. The claims of the successor patent “Pseudopolymorphic forms of a HIV protease inhibitor,” WO 2003106461 A2, are analyzed and shown to be invalid from both scientific and ethical viewpoints. It is established that darunavir was initially used as its ethanolate. Darunavir is one of the best protease inhibitors of both types of HIV. Currently, not only darunavir ethanolate but also amorphous darunavir (unsolvated) are used as active pharmaceutical ingredients with INN darunavir. This was confirmed by x-ray diffraction studies. Justification for the orderly invalidation of this patent in the RF was given.

By example of abacavir sulfate – a parent drug substance protected by a series of patents – it is demonstrated that neglect of the physicochemical properties and chemical laws, together with incorrect use of terminology, allowed additional patent protection for this drug to be carried out. In Eurasian patent EA 001809, the correct name of original substance was replaced by incorrect synonym and some contradictory, not quite reliable data, together with data presenting no novelty about the object were introduced into the formula of invention. This approach to prolongation of the period of patent protection for the parent drug substance is impermissible scientifically and inacceptable ethically. The results of investigation of abacavir sulfate by the method of x-ray diffraction (USP RS) showed that this substance is completely identical to abacavir hemisulfate according to published data on the crystalline structure of this drug. Indeed, both substances are neutral salts, have the same molecular formula (C 14 H 19 N 6 O) 2 SO 4 , and possess a molecular mass of 670.76. Therefore, there were no grounds to repeatedly patent the existing drug (abacavir sulfate) under the name of abacavir hemisulfate, which is erroneous for the neutral salt (1 S ,4 R )-4-[2-amino-6-(cyclopropylamino)-9 H -purin-9-yl]cyclopent-2-en-1-methanol.

Using abacavir sulfate substance and medicinal formulations as an example, this being an agent used as an active pharmaceutical substance (APS) protected by a series of patents, we demonstrate that additional patenting has occurred because its physicochemical properties and the laws of chemistry have been ignored and professional terminology has been applied inappropriately. Eurasian patent No. EA 001809 includes substitution of the correct chemical name of the patented substances with an erroneous synonym, and the statement of claim, along with lack of novelty of the data on the properties of the patented substances, includes contradictory and unreliable information irrelevant to the item subject to the patent. This approach to prolonging the period of legal protection of a substance used as an APS is not acceptable either from the scientific or from the ethical points of view. Our x-ray diffraction study of abacavir sulfate (USP RS) showed that this substance and abacavir hemisulfate are identical, on the basis of published data on the structure of abacavir hemisulfate crystals. Each of these substances is a neutral salt and each has the atomic formula (C 14 H 19 N 6 O) 2 SO 4 and a molecular weight of 670.76. Thus, repatenting a known APS (i.e., abacavir sulfate) as a new substance under a name incorrect for a neutral salt, i.e., (1 S ,4 R )-4-[2-amino-6-(cyclopropylamino)-9 H -purin-9-yl]cyclopent-2-en-1-methanol hemisulfate, is unjustified.