This 2019 US human clinical trial reported preliminary results. See Reanalysis of findings from a senolytics clinical trial for
“Senescent cells, which can release factors that cause inflammation and dysfunction, the senescence-associated secretory phenotype (SASP), accumulate with ageing and at etiological sites in multiple chronic diseases. Senolytics, including the combination of Dasatinib and Quercetin (D + Q), selectively eliminate senescent cells by transiently disabling pro-survival networks that defend them against their own apoptotic environment.
Since the target of senolytics is senescent cells, these drugs do not need to be continuously present in the circulation in the same way as drugs whose mechanism of action is to occupy a receptor, modulate an enzyme, or act on a particular biochemical pathway, at least in mice. Intermittently administering D + Q effectively circumvents any potential off-target effects due to continuous receptor occupancy or modulation of an enzyme or biochemical pathway.
To test whether intermittent D + Q is effective in targeting senescent cells in humans, we administered a single 3 day course of oral D + Q and assayed senescent cell abundance 11 days after the last dose in subjects with DKD [diabetic kidney disease], the most common cause of end-stage kidney failure and which is characterized by increased senescent cell burden.
In this interim report of findings, we found the single brief course of D + Q:
- Attenuated adipose tissue
and skin senescentcell burden,
- Decreased resulting adipose tissue macrophage accumulation,
- Enhanced adipocyte progenitor replicative potential, and
- Reduced key circulating SASP factors.”
“In adipose tissue D + Q significantly reduced raw numbers of:
- p16INK4A+ cells by 35%;
- p21CIP1+ cells by 17%;
- SAβgal+ cells by 62%;
- CD68+ macrophages by 28%; and
- Crown-like structures by 86%.”
https://www.ebiomedicine.com/article/S2352-3964(19)30591-2/fulltext “Senolytics decrease senescent cells in humans: Preliminary report from a clinical trial of Dasatinib plus Quercetin in individuals with diabetic kidney disease”
In a referenced 2019 rodent study by many of the same researchers:
“We also found that even Q alone can prevent high fat diet-induced increases in markers of senescence, renal fibrosis, decreases in renal oxygenation, and increased creatinine in mice, although Q alone did not prevent insulin resistance.”
The rodent study’s 50 mg/kg quercetin dose scaled human-equivalent dose would be (0.081 x 50 mg) = 13.3 mg/kg. This was 375% higher than a 1,000 mg/75 kg quercetin dose (clinical trial participants’ weights weren’t disclosed.)
https://onlinelibrary.wiley.com/doi/full/10.1111/acel.12950 “Targeting senescent cells alleviates obesity‐induced metabolic dysfunction”