Opposition to Sugen’s Lung Cancer Drug Patent Withdrawn

collusionSugen Inc. has sidestepped a post grant opposition to its lung cancer drug Xalkori (crizotinib) after what seems like a settlement with opponent Fresenius Kabi Oncology Ltd. Also engaged in the development and manufacture of cancer drugs, Fresenius Kabi filed two post grant oppositions to Sugen’s Xalkori patent in 2012 on multiple grounds. On 29th April, 2015, the Controller issued a decision allowing Fresenius Kabi’s request for withdrawal of their oppositions. It is unclear how and why this withdrawal came about, with the company only noting that it ‘no longer has business interest’ in the crizotinib patent. There are several ambiguities with the procedural history as well. A shout out to the advocates involved to please help explain some of these information gaps!

First Patent Opposition:

The first patent opposition filed on 18th October, 2011 opposed the patent on grounds listed in Sections 25(2)(e) – obvious and clearly does not involve any inventive step, 25(2)(f) – is not an invention within the meaning of this Act and 25(2)(g) – the complete specification does not sufficiently and clearly describe the invention.

Second Opposition:

The second opposition filed on 20th October, 2012 was on the ground that Sugen had failed to make mandatory disclosures to the Indian Patent Office (IPO) as required by Section 8 of the Patents Act, 1970.

Section 8 requires that when an applicant for a patent under is prosecuting another application for a patent in any other country in respect of the same or substantially the same invention, she must file the following additional information with his application:

1. a statement setting out detailed particulars of such foreign application;

2. an undertaking that, up to the date of grant of patent in India, he would keep the Controller informed in writing, from time to time, of detailed particulars of the foreign application.

As the initial post grant opposition argues, Section 25(2)(h) explicitly lays down the failure of the applicant “to disclose to the Controller the information required by section 8” or the furnishing of “information which in any material particular was false to his knowledge” as a ground for revocation of a patent.

The Opponent argued that while Sugen had made initial disclosures in relation to the suit patent, they had failed to make disclosures pertaining to the prosecution of patent applications for “substantially the same invention” in other foreign jurisdictions as per Section 8. In particular, the Opponent cited patents applications with publication numbers US2006128724 and US2006046991 (granted in 2011 in India as Patent Numbers IN243571 and IN250050, respectively) as substantially the same invention and yet not brought to the attention of the IPO. The opponents also cited Chemtura Corporation v. Union of India and Hoffmann-La Roche v. Cipla to support their argument that polymorphs of a compound would be substantially similar for the purpose of Section 8 disclosure.

On 24th July, 2013, the Patentee filed a petition for the dismissal of both oppositions.

Settlements and Slow Processing by the IPO

Information on the progress of this case has been very difficult to glean given the haphazard uploading of documents by the IPO n their website. While the Controller General of Patents, Designs and Trademarks makes documents in relation to a patent application and opposition public on ipindia.nic.in the documents are not organised at all. Given my perusal of the documents uploaded for this case, they do not seem to be complete either. For example, while the second opposition has been uploaded, the first is not. [However, this might be for confidentiality reasons].

As for the progress of the case, on 19th August, 2014, the Opponent filed a request for withdrawal of their opposition with the IPO stating that they do “not have business interest in the subject patent at present”. In the same, they indicated that they have corresponded with the Patentee and both parties have agreed to bear their own costs. Despite this request, the IPO seems to have continued with the matter judging from a letter from Anand and Anand, the Patentee’s lawyers, to the IPO dated 20th December. The letter is in response to a letter dated 12th December from the IPO forwarding the Opposition Board report, as earlier requested by the Patentees to them and setting a date for hearing of the matter on 16th January, 2015. The Patentee’s lawyers sent a second letter dated 12th January intimating the IPO that withdrawal requests were made by the Opponents, thereby rendering the hearing dated 16th January unnecessary. It is unclear why the Patentees sent this second correspondence. The only logical conclusion is that the IPO had failed to respond to the withdrawal request and continued to require the presence of the Patentees at the hearing. It is only on the 29th of April, 2015 that a decision allowing the withdrawal was passed by the Controller.


This withdrawal follows a series of settlements including Natco dropping its challenge of BMS’ patent for Hepatisis B drug ‘entecavir’. This is after a US District court invalidated BMS’ patent and the Delhi High Court refused an interim injunction against generic manufacture of the same drug by Ranbaxy on the ground of the patent’s prima facie vulnerability [See Shamnad’s post on this here]. As Madhulika argues here, this development, as recent as January this year, is strange given that other generics have sidestepped BMS’ process patent and launched the drug in the market. Cipla has also followed suit and is in talks with BMS to settle the matter amicably.

As C H Unnikrishnan has argued in the Mint, these settlements and deals between brand and generic pharmaceutical companies can mean that “patients suffer as access to cheaper medicine is restricted.” Most of the flexibilities that have been inserted into the Patents Act depend on healthy opposition to brand pharmaceutical patents. This is especially important given the tremendous workload on the IPO and the serious shortcomings in terms of both personnel and resources at their disposal resulting in a large percentage of patents granted without independent and rigourous review. Shamnad highlights the critical important of opposition proceedings in his report here, where it was found that 73% of oppositions are successful, indicating error in the initial grant! The new partnerships between brand and generic companies might mean that those who care about access to medicines might need to soon stop relying on generics alone to ensure the availability of medicines at affordable rates.

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2 thoughts on “Opposition to Sugen’s Lung Cancer Drug Patent Withdrawn”

  1. Finally the commercial side of the generic’s interest in patent litigation is becoming apparent to all. The blogs may lament this new trend but it was all too clear to patent litigators that both sides are in it for the money – at least the innovator brings a new drug to the market. The characterization of generics as messiahs of public health was nothing short of ignorance.

  2. Rupali, I asked this question in another post on patent settlements and repeat it here. What is the problem with it? Why do bloggers like you and Mr CH Unnikrishnan (as extracted from the line in your post) assume that thereis prices will still be high? Shouldn’t there be a balance between infringement by generic companies, frivolous and frequent invalidation actions and the freedom for market players to enter into agreements with one another. Maybe the prices will actually come down since there may be no import.

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