A.K. PATHAK, J.

1. Plaintiffs have filed this suit against the defendant for permanent injunction praying therein that defendants, its directors, employees, officers etc. be restrained from making, using, selling, distributing, advertising, exporting, offering for sale or dealing in Sitagliptin Phosphate Monohydrate or any other salt of Sitagliptin in any form, alone or in combination with one or more other drugs or from doing any other thing that infringes the claimed subject matter of the plaintiffs‘ Indian Patent No. 209816. Damages, rendition of accounts and delivery up of the infringing materials has also been prayed.

2. Briefly stated, plaintiffs have alleged in the plaint that plaintiff no. 1 was formally known as Merck & Company, Inc. Plaintiff no. 1 has been incorporated under the laws of New Jersey, USA, having its principal place of business at Whitehouse Station, USA. Plaint has been signed and verified by its constituted Attorney-Mr. K.G. Ananthakrishnan. Plaintiff no.2 is a licensee of plaintiff no.1 for marketing, distributing and selling Sitagliptin as also Sitagliptin & Metformin combination in India, under the trade marks ISTAVEL and ISTAMET respectively. Mr. Chetan Gupta is the constituted attorney of plaintiff no.2 and is duly authorized to sign, verify and institute the plaint on behalf of plaintiff no.2.

3. Plaintiff no.1 manufactures and markets a range of medicines for treatment of various ailments including diabetes. Plaintiff no.1 invented a molecule, namely, ‘Sitagliptin’ and got it patented in various countries, including India vide Indian Patent No. 209816. Application no. 26/CHENP/2004 was filed in India on 6th January, 2004; whereas international application no. PCT/US2002/021349 was filed in USA with priority date 6th July, 2001. Patent in India was granted on 6th September, 2007 under the title BETA-AMINO TETRAHYDROIMIDAZO (1,2-A) PYRAZINES and TETRAHYDROTRIOAZOLO (4, 3-A) PYRAZINES as DIPEPTIDYL PEPTIDASE INHIBITORS for the treatment of diabetes. Grant of patent was not opposed by any member of the public or interested party in India at any stage, despite extensive publicity given by the plaintiffs to its commercial products sold under the brand name ‘JANUVIA’ and ‘JANUMET’. The drug is used for treatment of Type II diabetes. Sitagliptin was approved for sale in USA in October, 2006 and in Indian market on 28th March, 2008. Patent no. 209816 has 20 claims and Sitagliptin is covered by claims 1 to 3, 5 to 10, 14 to 17, inasmuch as, it has been specifically claimed by claim 19 of the suit patent. Example 7 discloses the method for preparation of Sitagliptin hydrochloride salt.

4. Chemical structure of Sitagliptin is as under :

5. JANUVIA is a once daily pill with Sitagliptin as its active ingredient which helps lower blood sugar levels in people with Type II diabetes. Given below are some additional technical details pertaining to Sitagliptin :-

(i) IUPAC name of Sitagliptin – 7-[(3R)-3-amino-4-(2,4,5 trifluorophenyl) butanoyl]-3-(trifluoromethyl)-5,6,7,8-tetrahydro-1,2,4 triazolol [4,3 a] pyrazine;

(ii) Mechanism of action – it is DPP-4 inhibitor which helps the pancreas to produce more insulin. Thus, Sitagliptin helps lower blood sugar when it is too high;

(iii) The commercial product comprises the R stereoisomer of Sitagliptin. The suit patent claims both R and S forms of Sitagliptin in genus claim1, as well as the specific R-Sitagliptin molecule in claim 19.

6. Keeping in mind public interest JANUVIA was launched in India with price tag of Rs. 43 a pill which was roughly one-fifth of its price in the USA. The price of Rs. 43 was fixed after consulting nearly 350 doctors before launching the product in Indian market. Bulk packs of JANUVIA are imported from Italy and are sold by MSD Pharmaceuticals Pvt. Ltd. (licensee of the patentee), after packaging into consumer packs by Shasun Pharmac