The longevity treatment, commonly called simply "the treatment", is a medical procedure developed in the 2040s which dramatically increased human life span.
The treatment was developed by the Acheron medical and biotechnology team on Mars, led by Vlad Taneev, in the 2040s. It was first given to those who visited the Acheron complex. It was then administered to all Martians. Sax Russell secretly passed it on to the Areophany.
On Terra it was only accessible to the rich. Transnationals used it as an argument to attract employees, who were awarded with the treatment in their contract. The resulting rift was one of the causes of World War Three.
Humanity was propelled into the hypermalthusian age and Terra suffered from overpopulation problems. A secondary impact of the unnaturally long lives as people reached and exceeded 200 years of age was memory loss.
The treatment proved it had limits when the elderly started dying without a single identifiable cause, a phenomenon called the quick decline. Sax Russell attempted to find a solution to both the quick decline and the memory loss problem. He created the memory treatment in the late 22nd century-early 23rd century. People accepted their fates with the quick decline, having lived sufficiently long lives.