GNT Pharma's 'Nellonemdaz' Completes US Patent Registration

GNT Pharma announced on the 8th that it has received a patent registration decision from the United States Patent and Trademark Office for its stroke treatment drug, 'Nellonemdaz.' This patent pertains to the use and formulation of Nellonemdaz derivatives that reduce disabilities in stroke patients undergoing reperfusion therapy.

GNT Pharma's 'Nellonemdaz' under development as a stroke treatment [Photo by GNT Pharma]

According to the 2022 report by the World Stroke Organization (WSO), stroke is a serious brain disease ranking as the second leading cause of death and the third leading cause of disability worldwide. As of 2019, it is estimated that there are approximately 100 million stroke patients globally, with 12.2 million new cases and 6.55 million deaths. The total cost for stroke treatment and management is reported to reach 940 trillion KRW.

Currently, the standard treatment for stroke includes thrombolytics and thrombectomy procedures to open blocked blood vessels, which are used in some patients. However, there are no drugs to prevent the subsequent death of brain nerve cells, leaving patients still exposed to the risks of disability and death. When a stroke occurs, in the acute phase, overactivation of N-methyl-D-aspartate (NMDA) glutamate receptors leads to calcium ion accumulation causing brain nerve cell death, and reactive oxygen species generated after vascular reperfusion accumulate, inducing progressive brain cell death. Over the past 30 years, NMDA receptor antagonists and antioxidants identified as single-target drugs have shown efficacy in animal models but failed in human clinical trials due to lack of disability improvement and side effects.

GNT Pharma's Nellonemdaz is a multi-target neuroprotective drug that inhibits NMDA receptors while removing reactive oxygen species to prevent brain nerve cell death after stroke. The company explained, "the safety of Nellonemdaz was confirmed through Phase 1 clinical trials involving 165 healthy subjects in the United States and China, and Phase 2 clinical trials involving 447 stroke patients in Korea and China." In a Phase 2 clinical trial conducted on 209 stroke patients who underwent thrombectomy within 8 hours, Nellonemdaz showed disability improvement effects compared to the placebo group, with particularly pronounced effects in patients with severe stroke. Nellonemdaz also demonstrated an effect in suppressing hemorrhage, a major side effect of reperfusion therapy.

The company stated, “As a result of these findings, we have received a patent registration decision from the United States Patent and Trademark Office for the ‘use and composition of Nellonemdaz for treating tissue damage and hemorrhage after reperfusion therapy.’”

Nellonemdaz completed its Phase 3 clinical trial earlier last month. This trial was conducted on 496 severe stroke patients who underwent intra-arterial thrombectomy within 12 hours at 24 university hospital stroke centers nationwide. The results of this trial are expected to be announced in the fourth quarter.

Byung-Joo Kwak, CEO of GNT Pharma, said, “It is very encouraging that the U.S. patent registration was decided at the time when the Phase 3 clinical trial verifying the efficacy of Nellonemdaz in stroke patients receiving standard reperfusion therapy has been completed. If a neuroprotective drug is developed, it could dramatically reduce disability and death after stroke alongside reperfusion therapy.”