The patent office has refused a patent for an invention by drug major Wockhardt regarding an oral salt form of diacerein, used to treat osteoarthritis, on the ground that the claims in the application lack inventive step.
Wockhardt claimed the ‘proposed invention’ was related to a pharmaceutical composition of rhein or diacerein, showing at least 25% reduction in soft stool effect as compared to a 50 mg diacerein formulation marketed under the trade name Art 50.
N Ramchander, assistant controller of patents & designs, patent office, Mumbai, while rejecting the application, observed that the application refers in broad terms to a pharmaceutical composition comprising rhein or diacerein.
It is well-known in the field of pharmacy that these active compounds have desirable properties against osteoarthritis, for instance. However, it is also well-known that both rhein and diacerein have less advantageous properties, like incomplete absorption by the digestive tract that can have consequences on the activity of the drug and as secondary effects.
“On consideration of all documents available on record and in view of outstanding objections raised at various stages during the prosecution of application still remaining outstanding as on the date, I refuse to proceed further on this patent application,” he ruled.
The first examination report of the application had raised objections that the claims do not meet the requirements of clarity and the application does not meet the criteria of inventive step, because the subject-matter of the claims does not involve an inventive step.
According to the assistant controller, as the applicant company or their authorised patent agent did not attend the scheduled hearing, the objections raised at various stages had been still outstanding.
However, Wockhardt had submitted a reply against the first examination report with an amended set of claims along with an explanation. On receipt of the reply, further examination was carried out thoroughly and the assistant controller found that the reply did not satisfy the objections raised in the first examination report. Subsequently, a hearing notice was issued and the company failed to attend the proceedings.