Cadila Healthcare Ltd., in a suit for patent infringement in respect of Indian Patents bearing Nos. IN 299505 (‘505), IN 312723 (‘723) and IN 345194 (‘194) has been successful in obtaining an interim injunction against by M/s. Morepen Laboratories Ltd.

IN’505 is a product patent. It claims Saroglitazar Mg. IN’723, is a patent for formulation of Saroglitazar Mg with an alkalising agent. IN’194, is a process patent.

The question before the Court, were twofold:-

1. Whether SAROGLITAZAR tablets 4mg/8mg offered for sale by M/s. Morepen Laboratories Ltd., through its advertisements with caption “coming soon” is a product infringing the registered patent IN’505 of M/s. Cadila Healthcare Ltd.;
2. Whether the patent IN’505 has already been prior claimed by Cadila, in its non-asserted prior patent IN 220639 (IN’639).

The arguments put forward by the Defendants were, mainly: –

1. Saroglitazar Mg is prior claimed, disclosed and completely protected by prior art, like IN’639. Thus, once IN’639 expires on 26th July 2021, the patented invention covered therein i.e. Saroglitazar Mg, will fall within the public domain and any person is entitled in law to commercialese the said invention without any liability.
2. IN’639 is a valid prior art to invalidate IN’505 under Section 64(1)(a) as IN’639 has a priority date which is earlier than IN’505. Saroglitazar Mg is squarely within the scope of claims 1-8 of the IN’639 patent.
3. In claim 8 of the IN’639, Saroglitazar and its pharmaceutically acceptable salts are specifically claimed. Further, claim 7 of the IN’639 specifically claims for the Markush structure of the claim 1, the Mg as one of the pharmaceutically acceptable salt. Therefore, Saroglitazar Mg (claimed in IN’505) is validly claimed and within the scope of claims 1-8, of N’639 patent.
4. Saroglitazar Mg is not eligible for any further patent protection beyond the expiry date of the IN’ 639 patent and that the IN’505 patent is liable to be revoked on the ground of prior claiming.
5. That Saroglitazar Mg is prior claimed, disclosed and completely protected within the scope of IN’639 and this is evident from identical Form 27’s of IN’505 and IN’639.
6. The PCT counterpart of IN’639 was published on 06.02.2003, bearing publication number WO/2003/009841 (WO’841). Of the various compounds of WO’841, compound of Example number 102 discloses Saroglitazar, while Example 202 and 203 disclose Saroglitazar sodium salt (Na) and Saroglitazar calcium salt (Ca2+) respectively as representative salt of Saroglitazar. When these disclosures are read together with claim ‘7’ of IN’639, it would be obvious to a person skilled in the art to make Magnesium (mg) salt, which is also the claimed subject matter of IN’505.

The Court noted the following while granting an injunction to the Plaintiff, :-

• Out of three registered patents, which are the subject matter under consideration, Defendants state that they have their own process and formulation of Saroglitazar Mg, which fall outside the scope of the asserted IN’723 and IN ‘194. The only patent therefore to determine injunction was IN‘505.
• The Court considered that Saroglitazar Mg is a novel and new invention with proven enhanced efficacy through clinical trial, and is a valid selection invention.
• In making the above finding, the Court agreed with the Defendant that –
• In the year 2001, for the first time, the molecule of Glitazar class was identified and the said invention is the genus patent IN’639 carrying a priority date of 26th July 2001. IN’639 contained millions of compound which were crystallised as one general formula (markush structure) where millions of permutations could be made. The query raised by the Patent Office before granting patent in respect of novelty and prior art, were satisfactorily explained and overcome.

The Court therefore held that Cadila’s patent IN’505 is an improvement and modification of the prior invention resulting in enhancement of efficacy as envisaged under Section 3(d) of the Patents Act. The Court further held that the challenge of the respondent that the subsequent patent is an attempt to evergreen the monopoly is baseless. As per the Court, except a bald claim, no convincing material has been placed on record to show that the specification claim No. 1, 7 and 8 of IN’639 is Saroglitazar and the addition of Mg is disclosed or covered in the previous patent, IN’639.

The Court also seemed to agree with the argument of the Defendant that the Forms-27 are identical since they are pertaining to working of IN’639 through the base molecule ‘Saroglitazar free acid’ and to reach the commercial product Saroglitazar Mg, Saroglitazar free acid is a necessary intermediate. Therefore, the commercial figures of both the patents, IN’639 and IN’505 are the same.

The Defendants also referred to the decision in the Astrazeneca case of the DHC wherein the injunction has been refused to the Plaintiff. However, the Court held that, the Astrazeneca suits were successfully defended by the defendants because :-

1. the subject drug “Ticagrelor” is covered by several patents with different dates of expiry;
2. the material fact that Patent No. 241299 (the genus patent) expressly covers and discloses “Ticagrelor” and had expired on 14.07.2018 was suppressed by the Plaintiff;
3. form- 27 submitted by the plaintiff for IN’229 expressly refers to “BRILINTA” and “AXCER” as products being covered by IN’229. Therefore, the novelty and inventive step of the suit patent found to be seriously questioned;
4. the claim of the plaintiff that “Ticagrelor” is not disclosed in IN’229 and is not anticipated by IN’229 is subject to a strong challenge.

The Court further held that, the question of law involved in, both, the present case and the Astrazeneca case may be identical, but there is fundamental difference in facts of these two cases. The Court held that in the present case, the Plaintiff, Cadila has shown that IN’505 is a valid selection patent, unlike, in Astrazeneca case, wherein the evidence placed before the Court for consideration without any iota of doubt had lead to the conclusion that, “Ticagrelor” is encompassed and claimed in IN’229.