A court is to decide on the legal dispute between Hanmi Pharmaceutical and Novartis over the patent of Novartis’ diabetes treatment vildagliptin in July.

Hanmi has been trying to avoid Novartis’ patent infringement by altering the salt form of vildagliptin in a generic drug. In particular, Hanmi in early this year obtained the license of the vildagliptin-containing generic drug by excluding the original drug's particular regimen patent that was recently extended.

The Intellectual Property Trial and Appeal Board (IPTAB) determines the scope of Hanmi’s passive rights regarding its generic copy Vildagle next month. In December, Hanmi sought regulatory approval for Vildagle. At the same time, it requested IPTAB’s ruling on whether Hanmi’s Vildagle could avoid patent infringement if it excludes one of the authorized regimens of Novartis’ Galvus.

Vildagle is a generic drug of Novartis’ Galvus (vildagliptin) with a change in the salt form.

Hanmi asked the court if Vildagle could avoid infringing the patent of Galvus.

In September last year, the IPTAB ruled that even though Vildagle’s salt form was altered, it was still a latecomer that breached the patent of Galvus. In response, Hanmi notified Novartis that it would sell Vildagle after Galvus’ patent expires.

However, Hanmi tried a new strategy, seeking the license for Vildagle, excluding one of the regimens of Galvus. Hanmi did not notify Novartis about the application for the Vildagle permit.

Novartis’ Galvus has the permit in five different regimens – monotherapy, combination with metformin, two-drug combo with either metformin or sulfonylurea or thiazolidinedione, three-drug combo with metformin and sulfonylurea, and combo with insulin.

Hanmi obtained the license for Vildagle with four kinds of therapies of Galvus, excluding the combo therapy with sulfonylurea or metformin that got the permit for the first time.

The patent of the excluded regimen has been extended.

The Ministry of Food and Drug Safety approved Vildagle in January. In April, Hanmi also obtained reimbursement for the drug.

Novartis filed an administrative suit against the food and safety ministry to stop the ministry from giving the nod for Vildagle, but a Seoul court turned down the request.

Hanmi said it would not sell Vildagle until it receives a ruling from the IPTAB, and the Seoul Administrative Court acknowledged Hanmi’s intention.

Novartis, however, said Hanmi’s claim is an arbitrary law interpretation with little evidence.

In the previous cases, the main scope of the extended patent rights of a pharmaceutical product is considered as “target disease and efficacy” in the drug license, the multinational drugmaker said.

Both Galvus and Vildagle are used to treat type-2 diabetes with the same effectiveness, the company added.

Hanmi’s argument -- that the protection of patent rights differs before and after the extension of the patent for an authorized drug – is a unilateral claim that cannot be found anywhere in the world, Novartis said.

If the IPTAB recognizes Hanmi’s new way of avoiding patent infringement, other local drug companies may try the same tactic, and repercussions will be significant, observers said.

Novartis and Hanmi had co-promoted Novarti’s Galvus from 2014 to 2016.

kym@docdocdoc.co.kr

<© Korea Biomedical Review, All rights reserved.>