ST Pharm said Tuesday that the U.S.’s National Institutes of Health (NIH) has selected the company’s STP03-0404, a new drug candidate for the treatment of human immunodeficiency virus (HIV) infection, as part of the institute’s life science research project.

STP03-0404 is an HIV integrase inhibitor that acts on a non-catalytic site that is not catalytically active. It is a first-in-class drug candidate that can overcome drug resistance limitations of existing drugs.

The company will receive approximately $1.39 million from NIH over the next five years.

ST Pharm is currently working with Professor Kim Baek of the University of Emory to establish the mechanism of action of STP03-0404.

The newly identified mechanisms of action are the removal of the capsid, which protects the viral RNA, and the complete elimination of the ability of HIV to re-express in host cells.

Conventional AIDS treatments such as reverse transcriptase inhibitors and protease inhibitors have limitations due to side effects, drug interactions, and drug resistance. Although some companies have developed an improved catalytic active site integrase inhibitor, there is still a need for a new therapeutic agent to solve the drug resistance problem.

“Although the development of HIV treatment has led to AIDS becoming a chronic disease rather than a fatal disease, there is a pressing need to develop a fundamental therapeutic drug due to the development of tolerance,” a company official said.

The research into the new mechanism of action mechanism, which will be supported by the NIH, is expected to play an important role in the development of therapeutic agents for the cure of HIV infection, he added.

ST Pharm is conducting pre-clinical trials for STP03-0404 in Korea.