HK Innoen K-Cab wins substance patent appeal... Protection until 2031

HK Innoen K-Cab Series. Photo by HK Innoen

Biohealth company HK inno.N recently announced on the 6th that it won the second trial lawsuit regarding the compound patent of the new drug for gastroesophageal reflux disease, 'K-CAB Tablet (K-CAB),' following the first trial. Not only the Patent Trial and Appeal Board but also the Patent Court ruled in favor of HK inno.N, the original product developer, allowing HK inno.N to protect the patent until 2031.

K-CAB, the 30th new drug in South Korea, is a P-CAB class treatment for gastroesophageal reflux disease that HK inno.N received domestic approval for in July 2018. Since its launch in 2019, it has recorded nearly 200 billion KRW in outpatient prescription performance last year alone through various indications and formulation developments, ranking first in the domestic peptic ulcer drug market.

HK inno.N holds a 'compound patent' valid until 2031 and a 'crystalline form patent' valid until 2036 for K-CAB. The original term of the compound patent was until December 6, 2026, but the duration was extended to August 25, 2031, recognizing the time required for pharmaceutical research, development, and approval.

Generic companies filed for a declaratory judgment of non-infringement regarding the compound patent with three subsequent approved indications excluding the first approved indications of the original product K-CAB (erosive and non-erosive gastroesophageal reflux disease) to launch their products immediately after the original patent term expires in 2026. These companies argued that the extended patent rights apply only to the first approved indications of K-CAB and not to the subsequent approved indications.

HK inno.N selected Kim & Chang Law Firm as its litigation representative and proceeded with the compound patent lawsuit. Last year, the Patent Trial and Appeal Board (first trial) ruled in favor of HK inno.N, and recently, the Patent Court (second trial) also ruled in favor of HK inno.N.

This ruling concerns the indication of 'Helicobacter pylori eradication therapy' for K-CAB. The Patent Court ruled that this indication also falls under acid-related diseases treatable by suppressing gastric acid secretion, similar to the first approved indications, and thus the extended patent rights apply. This reaffirmed, consistent with the Patent Trial and Appeal Board's decision, that Article 95 of the Patent Act regarding 'use' should not be narrowly interpreted as limited to the first approved indications.

An HK inno.N official said, "This ruling will serve as an opportunity for domestic pharmaceutical bio companies to strengthen their commitment to new drug development. We will continue to strive to maximize the value of domestic new drugs through ongoing research." They added, "Since other ongoing lawsuits deal with the same or similar issues as this ruling, we expect positive outcomes."

Meanwhile, the lawsuit regarding the K-CAB crystalline form patent, which has a patent term until March 12, 2036, is currently in the second trial after HK inno.N lost in the first trial.