Single Compound, Two patents and a Landmark Decision


Single Compound, Two Patents and a Landmark Decision

Landmark decision

In a current landmark decision of the Delhi High Court, AstraZeneca AB and AstraZeneca Pharma India Limited (the Plaintiffs) have been denied the request for interim injunction towards Indian pharmaceutical companies.

AstraZeneca took several Indian generic drug makers to the Delhi High Court to prevent them from manufacturing and selling low cost versions of its diabetic medicine Dapagliflozin (in short "DAPA").

AstraZeneca was also seeking an injunction against Intas Pharmaceuticals and Alkem Laboratories, both defendants in a case relating to the manufacture of Dapagliflozin.

AstraZeneca was seeking a restraining order against marketing of dapagliflozin by several domestic companies, including Zydus, Eris LifeSciences, Torrent, Mico Labs, paving the way for affordable diabetes drugs in the Indian market.

Two Patents:
  • Indian Patent No. 205147 - The genus patent
    What is a Genus Patent ? A patent that covers not just one specific chemical but a group of related chemicals.
  • Indian Patent No. 235625 ? The species patent
    What is a Species Patent- a patent covering only one distinct and precisely identifiable Compound
One Drug:

Dapagliflozin drug- diabetic medicine (in short "DAPA")

As per a report, in 2019, the Dapagliflozin fetched in USD 1.54 billion in sales under brand names Farxiga and Forxiga. AstraZeneca has been granted patent for DAPA, in approximately 70 countries. DAPA is a drug used not only for treating type-II diabetes but also approved in the year 2020 for treating hypertensive heart failure in India. Dapagliflozin is marketed in India by Sun Pharma and Abbott Healthcare through licensing agreements with AstraZeneca.

The Case Highlights:

The questions that leads to the case of double patenting:

  • Whether or not the specific compound in question for Dapagliflozin as disclosed in Indian Patent No. 235625 (The species patent, that is legally in force and active) stands disclosed in Indian Patent No. 205147 (The genus patent, that is legally expired) both, in law moreover as on facts?
Claims of AstraZeneca:
  • Indian Patent No. 205147 is different from the invention claimed in Indian Patent No. 235625.
  • DAPA was first synthesized in 2001 i.e. after 12th August, 1999, being the priority date of Indian Patent No. 205147, the question of DAPA being disclosed in Indian Patent No. 205147 did not arise.
  • There is no indication in Indian Patent No. 205147 such as which parameters are critical or even which direction if taken out of the many choices available, would lead to DAPA.
  • Selling products based on the new invention covered by Indian Patent No. 235625 since the year 2015.
Defendant Arguments:
  • Appellants/plaintiffs deemed to have admitted that DAPA stood fully and particularly described in Indian Patent No. 205147.
  • Indian Patent No. 205147 expired on 2nd October, 2020 and there could thus be no interim injunction qua Indian Patent No. 205147.
  • Defendants have raised a credible challenge to the validity of Indian Patent No. 235625.
  • The appellants/plaintiffs have admitted that DAPA is claimed in Indian Patent No. 205147. There was an objection by the US Patent and Trademark Office (USPTO) to the application of the appellants/plaintiffs equivalent to Indian Patent No. 235625 in India, on the ground of prior claiming i.e. obviousness-type double patenting. The appellants/plaintiffs did not contest the said objection and on the contrary agreed to the term of patent thereunder to be coterminous with the term of the patent equivalent to Indian Patent No. 205147.
  • Working statement in Form 27 filed in relation to Indian Patent No. 205147, also furnished the working of DAPA, again admitting DAPA to have been part of Indian Patent No. 205147.
  • Public interest Sun Pharma Laboratories Limited and Abbott Healthcare Private Limited were marketing under various brand names and various disclosed combinations, at Rs.54.40 paise for a 5 mg. dose and at Rs.57.29 paise for a 10 mg. dose, the respondent(s)/defendant(s) were selling their drug for Rs.13.90 paise for 5 mg. dose and Rs.17.50 paise for a 10 mg/ dose; and, (y) that in the prevalent Corona Virus pandemic times, the probability of a diabetic person being afflicted with the virus is exponentially high.

The case seems interesting and in our point of view yet again depicts the importance of carefully analysing the in question patents. What attracted our attention is the citation of Form 27 (working of patents) and the USPTO history of the counterparts of the in-question patents as impactful evidence. The depth of analysis and carefully examining the prosecution history can have instrumental impact when representing case against a multinational organization in case of such stature.