Toward carbon monoxide based therapeutics: carbon monoxide in a pill

As one of the three known gasotransmitters, carbon monoxide (CO) has demonstrated therapeutic potential against a wide range of human diseases. However, development of CO as a therapeutic agent is severely impeded, primarily due to the lack of pharmaceutically acceptable delivery forms of CO. Gaseous CO may only have limited utility under carefully controlled clinical environment. As a result, there have been efforts in developing metal-based CO-releasing molecules and organic CO-releasing molecules that require light activation. We are interested in developing CO prodrugs, which are metal free and release CO spontaneously under physiological conditions without light irradiation. In this review, we summarize progress in this area with a focus on a recent patent and related publications.