Two old cancer drugs outperform a newer rival at clearing the body’s worn-out cells
In a mouse model of spinal disc degeneration, a cheap, decades-old drug combination beat a newer and more expensive competitor.
As the body ages, certain cells stop dividing but refuse to die. Instead, they linger and release a stream of inflammatory signals that damage surrounding tissue — a process researchers call the senescence-associated secretory phenotype, or more plainly: broken cells making their neighbours sick. In joints, muscles, organs, and spinal discs, these so-called senescent cells accumulate steadily, contributing to the physical decline associated with getting older.
A class of drugs known as senolytics was developed specifically to clear these cells. The best-known combination is dasatinib — originally a leukaemia drug — paired with quercetin, a plant compound also sold as a dietary supplement. Together they form D+Q, which has been studied for years. Navitoclax is a newer entrant: a potent senolytic that showed impressive results in lab studies, but also carries serious side effects, including the destruction of blood platelets.
The spine as a testing ground
In a mouse model mimicking the degeneration of intervertebral discs — the cushions between vertebrae that, when they break down in humans, cause back pain and disc herniation — all three drugs were put head to head. The outcome was striking: D+Q outperformed navitoclax on nearly every measured parameter. Disc structure was better preserved, inflammatory markers were lower, and the tissue appeared healthier overall.
This matters for several reasons. It confirms that the D+Q combination, despite being one of the oldest subjects of senolytic research, remains a serious contender for clinical use. It also challenges the assumption that newer automatically means better in this field. Navitoclax’s sharper mechanism against certain cell types does not reliably translate into superior outcomes in complex biological tissue.
The gap between mice and people
These experiments involve mice, and the distance to human patients is considerable. Human intervertebral discs are larger, differently structured, and subject to different mechanical forces than those in rodents. A treatment that works in mouse spines may behave differently in human backs.
Still, early human trials with D+Q are underway — in older adults with physical frailty and in patients with chronic kidney disease. Safety profiles so far appear manageable. Whether senolytics will ever become standard care for back problems or age-related conditions more broadly remains distant. But in a field racing to find ever more powerful tools, the finding that the oldest and cheapest combination still leads the pack is worth sitting with.