There have been a number of proposed senolytic compounds ranging from repurposed cancer drugs to naturally occurring flavonols. Fisetin has been in the new more recently as a potential senescent cell clearing compound known as a senolytic.
Fisetin is a naturally occurring flavonol and part of the flavonoid family of polyphenols. Fisetin also acts as a pigment and influences the color of various fruits and vegetables. It can be found in many common fruits and vegetables, although the amounts greatly vary. It is also readily available as a dietary supplement for a relatively low cost.
University of Minnesota Medical School faculty member Paul D. Robbins and Laura J. Niedernhofer and Mayo Clinic investigators James L. Kirkland and Tamara Tchkonia published “Fisetin is a senotherapeutic that extends health and lifespan” in the journal EBioMedicine in October 2018 .
Fisetin is undergoing human clinical trials to test its ability to remove harmful senescent cells which accumulate with age. A phase 2 study to address age-related frailty was conducted from February 2018 to December 2019 with some positive initial results.
 Yousefzadeh, M. J., Zhu, Y., McGowan, S. J., Angelini, L., Fuhrmann-Stroissnigg, H., Xu, M., … & McGuckian, C. (2018). Fisetin is a senotherapeutic that extends health and lifespan. EBioMedicine, 36, 18-28.