Scientists have tested an anti-aging drug that significantly extended the lifespan of laboratory mice by 25 percent. The mice, known as “supermodel grannies,” were used to understand if human lifespans can be extended.

Researchers found that the medicated mice were healthier, stronger, and developed fewer cancers than their unmedicated peers.

The drug targets the interleukin-11 protein, and researchers from the MRC Laboratory of Medical Science, Imperial College London, and Duke-NUS Medical School in Singapore conducted two experiments to test it.

The first experiment involved genetically engineered mice that couldn’t produce interleukin-11, while the second experiment involved giving the drug to a 75-week-old mouse to eliminate interleukin-11 from its body. This mouse was roughly equivalent in age to a 55-year-old person.

The results, published in the science journal Nature, showed that the mice’s lifespans increased by 20 to 25 percent on average, depending on their sex.