The Palo Alto Longevity Prize is set to give away $1,000,000 to a team of scientists who can best figure out how to slow aging. The prize is broken into two parts. $500,000 will be given to the team that can best extend a mammal’s lifespan, and $500,000 will be given to a team who can “turn back the clock” in a mammal.

Registration for the competition closed at the end of 2015. The competition itself, however, won’t end until 2019 as many of the proposed therapies take a while to test. Teams from all around the world are competing, testing therapies such as gene modification and hormone therapy.

One such team is comprised of researchers from Japan and the United States testing a drug that blocks plasminogen activator inhibitor-1 (PAI-1). This protein is normally used by the body to dissolve clots. But these scientists believe that by blocking and controlling the protein, they may be able to extend human life.

The drug has already been shown to work in mice and has successfully quadrupled their lifespan. Currently, it’s being tested on 12 people in Japan. The American members of the team are hoping they can begin clinical trials here by the end of the year.

According to Keith Powers, president of the Palo Alto Prize, the prize is about encouraging focus on and research into longevity. “It’s not necessarily about living forever,” said Powers. “It’s more about if we start to live healthier and we find pathways for everyone to live healthier, as a result of living healthier we will live longer.”