Buprenorphine - Norway

On Sep 08, 2017, Oslo District Court of Norway issued a decision in buprenorphine transdermal patch case & found patents-in-suit invalid under lack of inventive step.

The case concerns the validity of the Norwegian patents NO 334290 (NO’290), NO 332248 (NO’248), & alternative sets of claims A and B, and NO 333139 (NO’139). The defendant, Mundipharma AS (Mundipharma), is the holder of the patents-in-suit in the case. One of Mundipharma's products is a transdermal patch for the administration of buprenorphine over a period of seven days. The transdermal patch marketed by the above companies has the commercial name of Norspan in Norway, while in certain other countries it is marketed under the commercial name of BuTrans.

The plaintiff, Orifarm Generics A/S, Orifarm Generics AS and Orifarm AS (Orifarm) is the holder of three marketing authorisations for a transdermal patch containing buprenorphine under the trade name of Buprefarm. The marketing authorisations encompass three products of different strengths; 5 micrograms/hour, 10 micrograms/hour and 20 micrograms/hour, respectively. On the basis of their marketing authorisations, Orifarm planned to enter the Norwegian market with Buprefarm. On 17 June 2016 Mundipharma petitioned for an interim injunction to stop Orifarm's sale of Buprefarm. On 20 June 2016, Oslo Court of Execution and Enforcement issued a ruling whereby the petition was accepted. On 19 August 2016, Orifarm issued a writ of summons before Oslo District Court, with the prayer for relief that all three patents should be declared invalid and that Mundipharma should be ordered to pay compensation for the loss Orifarm suffered as a consequence of the interim injunction. The main hearing in the case was held from 19 to 28 April 2017.

All three of the patents-in-suit concern a transdermal delivery device that includes buprenorphine for the treatment of pain. A shared feature of the patents is that they according to the patent description make it possible to produce a medicament that enables reduced plasma concentrations of buprenorphine over a longer period of time than what is possible according to prior art, while at the same time causing effective pain relief. Orifarm submits that all of the patents-in-suit are invalid. None of the patents-in-suit fulfill the requirement of inventive step and do thus not fulfill the requirements of section 2 of the Patents Act. The ground for patent for all of the patent claims is the dosing time period described in claim 1 of the patents. At the priority date, it is obvious to the skilled person to use transdermal delivery devices for buprenorphine as described in the patents for both 5 and 7 days, and the skilled person would have had a reasonable expectation of success.

Court defined technical problem as obtaining a more convenient and effective pain relief/pain treatment by means of the transdermal administration of buprenorphine. Court further held that it can be seen from the referenced literature that the patent concerns a problem of a nature that those skilled in the art were generally focused on solving. A dosage interval of one week was considered an advantage, both to make the medicinal product user friendly and economical to use. Other advantages are also described, like constant plasma values over an extended period of time, which would lead to fewer side effects. With respect to the reasonable expectation of success there are no indications to suggest that it will not work. In the literature there are also suggestions that one might simply increase the amount of active ingredient, possibly also adjuvants in the same proportion, to obtain a longer period of effect. It will only be by trying that the skilled person will be able to find any possible adjustments that must be made to the formulation to obtain an extended duration, but the Court finds it clear that the skilled person would have done this with a reasonable expectation of success.

Finally court held that based on an overall assessment to the skilled person it was obvious to solve the problem of finding a more effective and suitable transdermal administration of buprenorphine by choosing the solutions indicated in the patent. Thus Patents NO334290, NO332248, including the alternative sets of claims A and B, and NO 333139, are ruled invalid.