Patent office refuses Daiichi Sankyo's application for anticoagulant drug after pre-grant opposition from IP Alliance

Gireesh Babu, New DelhiWednesday, February 1, 2023, 08:00 Hrs  [IST]

The Indian Patent Office has refused to grant patent for Japanese drug major Daiichi Sankyo Company for its claimed invention related to anticoagulant drug Edoxaban, sold globally under the trade name Savaysa and Lixiana, following a pre-grant opposition from the Indian Pharmaceutical Alliance (IP Alliance).

The company's patent application claimed that the invention is to provide pharmaceutical preparation exhibiting satisfactory dissolution property in a wide pH range.

The company, in its patent specification, said that the basic compound in the application exhibits high solubility in a strong aqueous solution, but its solubility decreases in a neutral pH aqueous solution. The object of the invention in the application is to provide a pharmaceutical composition containing the basic compound as an active ingredient and exhibiting excellent dissolution properties.

The Assistant Controller of Patents and Designs, who heard both the sides regarding the patentability of the application, concluded that the claimed invention is obvious and does not involve inventive step over the prior art, it is not an invention within the meaning of the relevant section of the Patent Act, 1970 and it is not patentable invention within the meaning of Section 3(d) and Section 3(e) of the Patents (Amendment) Act.

Under Section 3(d) of the Patents Act, 1970, the mere discovery of a new form of a known substance which does not result in the enhancement of the known efficacy of that substance or the mere discovery of any new property or new use for a known substance or of the mere use of a known process, machine or apparatus unless such known process results in a new product or employs at least one new reactant, is not an invention patentable.

Similarly, under Section 3(e), a substance obtained by a mere admixture resulting only in the aggregation of the properties of the components thereof or a process for producing such substance is not an invention. However, the patent office dismissed the grounds of opposition relating to the lack of clarity and sufficiency and that the applicants failed to disclose the details of foreign applications under Section 8 of the Patents Act.

IPA opposed the patent on the main grounds that the claimed invention is obvious and clearly does not involve any inventive step under Section 25(1)(e) of the Patents Act, and it is not an invention within the meaning of the Act. It also raised opposition on the grounds that the claimed invention lacks clarity and sufficiency under Section 25(1)(g) of the Act.

IPA argued that the improvement in properties such as dissolution and stability are essential requirements for obtaining regulatory approval for manufacturing and marketing any drug commercially in any country based on their pharmacopoeias. If the dissolution property or any other properties mentioned in the pharmacopoeias is not obtained by using certain types of excipients, then a person skilled in the art will move or search for the right excipients to improve the properties to achieve the desired profile as per the standards of the pharmacopoeia. If such routine activity, being carried out on a daily basis by the entire pharmaceutical industry is considered inventive, every formulation of every drug will merit patent protection, it argued.

The medical composition of the compound edoxaban tosylate monohydrate was known in the form of tablets, powdered, granules, capsules for oral administration, it argued.

The drug, launched in Japan in 2011, is an orally active Factor Xa inhibitor which prevents the formation of blood clots by specifically, reversibly and directly inhibiting the enzyme, Factor Xa, a clotting factor in the blood, according to the company. It has contributed significantly to the global revenues of the company, according to the Daiichi Sankyo Group Value Report, 2022.

The drug brought in a revenue of Japanese Yen (JPY) 205.6 billion from the global market, of which JPY 92.5 billion was from Japan, JPY 95.9 billion from Europe and JPY 14.3 billion from Asia, and Central and South America, while North America accounted for JPY 1.9 billion. The company's total revenue in the financial year 2021 was JPY 1,044.9 billion, it added.