By Vindhya Srinivasamani
Since the inception of the Patents Act, 1970, Indian
patent law has been a process patent regime in the field of pharmaceuticals.
Based on the recommendations of a committee chaired by Judge Rajagopala
Ayyangar in 1959, product patent protection in the pharmaceutical sector was
abolished in order to ensure that medicines were available to the public at
It was only in 2005, in order to comply with the
obligations under the Agreement on Trade Related Aspects of Intellectual
Property Rights (TRIPS) that India permitted patent rights to pharmaceutical products.
Thus, the law as it stands today under the Patents Act, 1970 (the Act)
expressly states that an invention under the Act means a new product or process
involving an inventive step and capable of industrial application. Although
much of the patent litigation till date in the field of pharmaceutical has
arisen out of product patent infringement, a recent judgment by the High Court
of Delhi in Glenmark Pharmaceuticals Ltd.
v. Symed Labs Limited
(OS) No. 60 of 2015, dated 5th Feb., 2015]
has brought back the spotlight on process patent infringement in the
pharmaceutical sector. In this case, the Division Bench of the Delhi High Court
set aside the order of the Single Judge of the Delhi High Court granting an
interim injunction in favour of the patentee plaintiff, Symed.
Relevant statutory provisions
It is important to note that rights of a process
patentee differ from that of a product patentee. Section 48 of the Act
demarcates the right of patentees and states that with respect to a process
patent, a patentee has the exclusive right not only to prevent third parties
from the act of using the patented process without consent but also to prevent
them from using, offering for sale, selling or importing the product obtained
directly by the patented process in India. This is in contrast to the rights of
a product patentee, whereby a product patent confers upon the patentee the
right to prevent third parties from making, using, offering for sale, selling
or importing the patented product in India.
Specifically with regard to process patent
infringement, Section 104 A of the Act is relevant. This provision states that
in the case of a suit for infringement of a process patent, if the patentee is
able to prove that the product manufactured by the patented process is
identical to the product manufactured by the defendant, then the burden of
proof in the infringement suit shifts to the defendant to establish that the
process used to manufacture its product is different from that of the patented
Major cases on process patent litigation in the pharma
One of the first major process patent infringement
litigation was initiated by Teva Pharmaceuticals Industries Ltd. (Teva) against
Natco Pharma Ltd. (Natco) in 2007. Teva filed a suit [CS (OS) 1708 of 2007; the
First Suit] for permanent injunction before the Delhi High Court against Natco
to restrain them from infringing Patent No.190759 for an invention titled “a method for manufacturing Co-polymer I
fraction". The patented process is used in the manufacture of the drug
glatiramer acetate that is useful in the treatment of multiple sclerosis. Natco
on the other hand contended that the process employed by them for producing
glatiramer acetate was entirely different from the process patented by Teva.
Further, Natco also filed a counterclaim for revocation of Teva’s patent.
However, by order dated 20th August,
2014, the Single Judge of the Delhi High Court dismissed the First Suit and the
counterclaim filed by Natco on the ground that both the parties failed to lead
evidence to support the averments made in the plaint or in the counterclaim.
While the First Suit and the counter claim were
pending trial before the Delhi High Court, Teva filed another suit against
Natco in 2012 [CS (OS) 3193 of 2012 - the Second Suit] for a quia timet permanent injunction to
restrain Natco and its agents from infringing Teva’s patent no. 190759. After a
series of appeals before the Division Bench of the Delhi High Court and
subsequently the Supreme Court, the Bench restored the matter to the Single
Judge of the Delhi High Court who has vide
order dated 16th January, 2015 reserved judgment in the Second Suit.
Bristol-Myers Squibb (BMS) filed a suit for
infringement (O.S No. 670 of 2014) before a trial court in Hyderabad against
Mylan Laboratories Ltd. (Mylan) to prevent them for infringing its processes
patented in India by virtue of Patent Nos. 206217 and 210496. The patents in
suit were directed to a stereo-selective
process for preparing substituted oxobutanes and a process for preparing alpha-chloroketones, respectively. Both the above mentioned processes are used in the
manufacture of Atazanavir, an antiretroviral drug for the treatment of AIDS.
Specifically BMS sought to prevent Mylan from manufacturing Atazanavir using
the patented process and exporting the same to Venezuela.
Mylan contended that its manufacture of Atazanavir
Sulphate Capsules does not fall within the purview of the patented processes of
BMS. Further, Mylan also asserted that the suit patents are immaterial and
irrelevant to Mylan’s export of Atazanavir Sulphate product to Venezuela in
compliance with the contractual obligations undertaken with International
Bodies i.e., Pan American Health Organization (PAHO) / World Health
Organization (WHO). The trial court by order dated 26th Sept., 2014 denied BMS
an interim injunction for having failed to establish a prima facie case of infringement of its process patents. On appeal
the Andhra Pradesh High Court [AP High Court vide order dated 5th Dec., 2014 (Bristol-Myers Squibb Holdings Ireland v. Mylan Laboratories Limited -
2015(1)ALT4)] upheld the order of the trial court denying an interim injunction
in favour of BMS.
The AP High Court interpreted Section 104 A of the Act
and held that in a suit for infringement of a process, if the patentee proves
that the product of the defendant is identical to the product obtained
by the patented process, then the burden of proving that the process used by
the defendant in obtaining his product is different from the patented process
lies on the defendant. The AP High Court also held that in the context of
Section 104A of the Act, the word ‘identical’ means the same and not similar.
On the question as to whether BMS was successful in
establishing a prima facie case of
infringement so as to warrant an interim injunction in its favour, the High
Court observed that the suit patents neither claim the drug Atazanavir nor any
process for the preparation of Atazanavir but were essentially directed to the
process of producing intermediates used in the manufacture of Atazanavir.
Further, the Court also observed that BMS did not assert that Mylan was
producing the intermediates claimed in the suit patent, namely, choloroketones
or oxobutanes. Thus, in the light of failure by BMS to satisfy the threshold
under Section 104A of the Act, the High Court held that BMS failed to produce
evidence to show that the process used by Mylan is the same as that of the
process covered under the suit patent.
On April 12, 2013, Symed filed a suit before the Delhi
High Court [C.S. (OS) No. 678 of 2013] seeking an injunction restraining
Glenmark Pharmaceuticals Limited and Glenmark Generics Limited from infringing
Symed’s process patents in their manufacture of Linezolid. Linezolid is useful
in the treatment of serious infections caused by Gram-positive bacteria that
are resistant to several other antibiotics[ see end note 1].
Symed asserted that its patent nos. 213062(‘062
Patent) and 213063 (‘063 Patent) are directed to a more economical, safe and
commercially viable process of manufacturing Linezolid as compared to the
processes known in the art. Based on the
fact that the patented processes were directed towards the production of
linezolid by producing novel intermediates such as, N - [3 – Chloro – 2 - (R) -
hydroxprophy1] – 3 – fluoro – 4 –morpholinyl - anlaniline” (CHFA claimed in
Claims 18 and 19 of the ‘063 Patent) and “N – 3 [Phthalimido – 2 - (R) -
hydroxprophyl] – 3 – fluoro – 4 (morpholinyl) aniline” (PHPFMA claimed in
Claims 23, 24 and 25 of the ‘062 Patent); Symed argued that the presence of any
of these intermediate compounds in the final product (Linezolid) would be
indicative of the fact that the product has been manufactured by the patented
process. It was further argued that on testing samples of the Linezolid
(marketed under the brand name ‘Lizolid’) manufactured by Glenmark both before
and after filing the instant suit, presence of intermediates PHPFMA, CHFA and
Zodiac-4 were detected (Zodiac-4 is obtained by carbonylating CHFA) and thus,
Glenmark was infringing Symed’s patents.
Glenmark, on the other hand, besides challenging the
jurisdiction of the Court to entertain the instant suit also filed a
counterclaim challenging the validity of the suit patents on the ground of lack
of novelty. Further, Glenmark asserted that the pre-suit lab reports did not
indicate the presence of CHFA, whereas, the post-suit reports showed the
presence of CHFA. Therefore, Glenmark assailed the veracity of Symed’s
averments as to the presence of the intermediates in the final product.
Glenmark also stressed that the presence of the intermediates Zodiac-4 and
PHPFMA in the final product prepared by Glenmark i.e. Linezolid API (Active
Pharmaceutical Ingredient) was not indicative of infringement as said
intermediate compounds could also be found in the final product produced by
processes of manufacture of Linezolid already known in the art.
Order of the Single Judge of the Delhi High Court
On hearing the above arguments raised by the parties,
the Single Judge vide order [see end note 2]
dated 19th Jan., 2015 granted an interim injunction in favour of Symed, thereby
restraining Glenmark from manufacturing Linezolid in a manner so as to result
in infringement of the suit patents.
With regard to the pertinent issue raised by Glenmark
as to the lack of detection of the intermediate CHFA in the pre-suit reports
and the sudden detection of the same in the post-suit reports, the Single Judge
dismissed the argument observing that this was possibly due to the fact that
the samples were not tested for CHFA and further, upheld Symed’s argument that
presence of CHFA, PHPFMA and Zodiac-4 is a strong indicator of the fact that
Glenmark employed Symed’s patented process to manufacture Linezolid API. The
Single Judge in coming to such a finding also considered the fact that the test
reports relied upon by Symed were from both Symed’s own facility and
In light of the above, the Single Judge held that
Symed satisfied all the tests for grant of an interim injunction, namely
establishing a prima facie case, that
the balance of convenience is in favour of Symed and that irreparable loss and
injury will be caused if the interim injunction is not granted.
Order of the Division Bench of the Delhi High Court
Aggrieved by the order of the Single Judge of the
Delhi High Court, Glenmark approached the Division Bench of the Delhi High
Court in appeal on the following two grounds:
prior commercial use of the product before filing of the process patents,
would not entitle Symed to an injunction, subsequently.
the Single Judge failed to adhere to the statutory mandate under the
proviso to Section 104A(1)(b) of the Act that the initial burden of proof
rests on the patentee to show that the product manufactured by the other
party is identical to the product manufactured by the patented process.
Essentially, it was asserted that the Linezolid API
manufactured by Glenmark was not identical to the Linezolid API manufactured by
the patented process because the intermediates or markers in the Linezolid
manufactured by Glenmark were different from the Linezolid manufactured by the
patented process. It was argued that merely because a product is known as
Linezolid API, it does not mean that the same is identical to the product
manufactured by the patentee directly through patented processes.
The Division Bench of the Delhi High Court observed
that in a case of process patent infringement, it was incumbent upon the Single
Judge to ascertain whether the requirements under Section 104A of the Act were
fulfilled. Specifically, it was observed that the Single Judge ought to
ascertain as to whether the Linezolid API manufactured by Symed was identical
to that manufactured by Glenmark.
Further, the Bench upheld the argument made by
Glenmark that while the ‘062 Patent results in Linezolid API with two
intermediates or markers, namely CHFA and Zodiac-4 and the ‘063 Patent results
in CHFA and PHPFMA; the Linezolid API manufactured by Glenmark consists of
three intermediates namely, Zodiaz-4, CHFA and PHPFMA. Thus, the Division Bench
held that this clearly indicated that Glenmark was manufacturing Linezolid API
by a different process.
In light of the above, the Division Bench vacated the
interim injunction granted by the Single Judge and directed Glenmark to
maintain accounts and file the same in Court along with a copy to Symed. The
next date of hearing in the instant case is 6th April, 2015.
In the case of process patents in the field of
pharmaceuticals, where the processes are mostly directed towards the manufacture
of a drug, proving infringement of such a process patent poses a significant
challenge. The primary reason for this difficulty in proving that a process has
been infringed is that there is no way to conclusively determine the process
used by the defendant. This is because the patentee will never be able to
legally enter the premises of the defendant to ascertain the actual process of
manufacture of the final product.
The above difficulty is probably the reason Article 34
was included in the TRIPS Agreement. In light of the obligations under TRIPS,
India enacted Section 104A of the Act which essentially reproduces Article 34
of TRIPS, whereby it is the defendant who is to establish that they did not
employ the patented process, provided the product manufactured by them is
identical to the product manufactured by the patented process.
It is to be noted that the Symed
the first process patent case in India that actually demonstrates the
difficulties and uncertainties that arise in establishing that the products are
identical. While markers and intermediates many be one way of establishing the
identical nature of two APIs there is no legal basis to say that it is the only
way. It will be interesting to see if courts continue to employ intermediates
as the criteria or if parties are able to convince the courts of other
parameters to ascertain the identical or distinguishing features between APIs,
as the case may be.
[The author is an Associate,
IPR Practice, Lakshmikumaran & Sridharan, New Delhi
- Source: Wikipedia
- Symed Labs v. Glenmark Pharmaceuticals and
Anr. – CS (OS) No. 678 of 2013, Delhi High Court