Jason Momoa is pleading for more "heroes" of the world to step up and help his close friend Travis Snyder on his fight against acute myeloid leukemia.
When the 42-year-old actor met Snyder, founder of The Color Run, in Hawaii six years ago, he didn't know much about cancer. With Snyder in need of a blood stem cell transplant, Momoa and Snyder recently spoke to PEOPLE in hopes of getting more potential donors for the Be The Match Registry.
"We met through happenstance and mutual friends after my first cancer battle in 2015," Snyder, 44, tells PEOPLE of meeting the Aquaman actor. "I think in the aftermath of treatment I was very focused on living every day with purpose and my heart was open and Jason wasn't quite as busy then and he lives with such a big giving heart and Aloha, we just connected instantly."
Snyder, a California resident, was diagnosed with acute myeloid leukemia in 2015. It's a type of cancer in which the bone marrow makes a large number of abnormal blood cells — the most common type of acute leukemia in adults — according to the National Cancer Institute.
It can be treated with a blood stem cell transplant, which replaces unhealthy blood cells, but Snyder initially didn't have any full matches in the Be The Match Registry, a national marrow donor program. He underwent chemotherapy, which put his cancer in remission. Since, the husband and father of three has relapsed three times — most recently in March, which has left him seeking a donor once again.
"[When I was first diagnosed] you get dealt the worst card of leukemia and then you don't have a match. It was really hard," Snyder says. "Throughout all of this, I think about my kids. Each relapse has been the hardest conversation to have with them. I just want to be able to keep raising these boys."
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Snyder praises Momoa for standing by his side and offering to help in any way. "Some of my friends kind of shrink when you're in trouble, or it becomes kind of surface-y," he adds. "And Jay was just right there again."
However, Momoa expressed frustration that he was "ignorant" about the registry for years and has now aged out of being a donor candidate. (The Be The Match Registry accepts anyone between ages 18 and 40 and they can sign up on the website.) Instead, Momoa vows to use his platform to encourage others to join the registry in case they are a match for someone in need.
"I'm supposed to be a superhero," the Aquaman star tells PEOPLE. "And you think, 'God, Anyone at any time, if you're just a part of the registry, you have an option to save a life.'"
"I just think this is pretty special-- We have the power to actually save someone's life and most people won't do that in a lifetime," Momoa continues. "So I think it's being a hero and being the match is something that I would love to help my friend out with-- and so many children, and other people [in need]."
Snyder is currently in need of a full match from the worldwide registries. Though there have been previous alternative options to receive transplants from "half matches," finding a fully matched donor is the preferred treatment.
Dr. Steven Devine, chief medical officer for Be The Match and associate scientific director of the Center for International Blood and Marrow Transplant Research, tells PEOPLE that patients like Snyder typically have difficulty finding a match because full matches are likely to come from someone with the same ethnic background.
"The more diversity we have on the Be The Match Registry, the greater the likelihood of us finding the best possible match for all of our patients," he notes. "Today, white patients will find a matching donor 79% of the time. Hispanic, Asian and Pacific Islanders will find a match less than half the time, and Black and African American patients are least likely to find a match. Their odds of finding a match are 30%."
"We know that the more people who join the registry, the greater the odds of helping patients find matching donors," Devine adds. "And it's simple – only requiring a cheek swab so you can be typed."
Because of the challenges, Snyder says even if he doesn't find a full match, he wants to — at least — increase the registry's list of potential donors.
"I know many people who have already died without a match," Snyder explains. "I obviously would love a match for myself. I care about that deeply. I want to raise my sons. I need more time. And, I'm asking the people to do that."
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"I also feel the obligation to raise it just generally," he continues. "Either way, this is a win-win for me, because if I, through this, find a match and it's better for me, great. And if not, I go out raising this thing as high as I can for generations to come."
Momoa explains that those who join the registry are "angels" who are giving hope to not only his friend, but many others across the world.
"I didn't know much about all different types of cancer and I haven't had someone pass in my family from it, and Travis is really my first experience. And something like this, absolutely, I can donate my time and platform," Momoa tells PEOPLE. "I just want to be able to help… It's just tearing me up that I can't save my buddy."
"And the great thing is, it's your choice," he says of joining the registry. "You don't have to. It's just giving hope to people that are out there. And I'm like, 'How could I not do this, and how could I not spread this awareness?' "