“Chrono-“ refers to something related to time of day, and chrono-therapy means that the time of day is important for the therapy. Cortisol is the day/night hormone in all individuals, and corticosteroid drugs disrupt the day/night cortisol rhythms and the day/night cycle of the body. Here, chrono is a safety concern of corticosteroids.
But the flip side of this is that some drugs may improve their efficacy if given at a certain time of day. Indeed, giving prednisone in a manner that is in synchrony with endogenous cortisol rhythms has been shown to be more effective for arthritis (Rayos) is a delayed release form of prednisone taken at night).
Drs. Robert Freishtat and Eric Hoffman developed methods of testing drugs for their ability to synchronize cells, and thus reduce the pro-inflammatory state. This intellectual property is licensed to ReveraGen for development of new chrono-therapy drugs.
Recently, vamorolone was found to be a ‘sychronizer’ drug in asthma cell models, where it was able to restore cell mitotic synchrony, and reduce the pro-inflammatory state (Freishtat et al. 2015).