Mom Has 3 Days to Get Son Life-Saving Treatment for Muscular Dystrophy Before He's Ineligible (Exclusive)

"My medicine is making me stronger," 7-year-old Hudson Sanford says after receiving a breakthrough gene therapy for Duchenne Muscular Dystrophy

<p>Melanie Sanford</p> Melanie Sanford with her husband, Phillip, and son, Hudson

Melanie Sanford

Melanie Sanford with her husband, Phillip, and son, Hudson
  • Melanie Sanford's son Hudson was diagnosed with Duchenne, a fatal, progressive form of muscular dystrophy

  • She was told Hudson would only live until age 28 until she found hope in a breakthrough gene therapy

  • Three days before Hudson would have aged out of eligibility for the treatment, he was able to receive the therapy — and now he's thriving

Melanie Sanford was worried that her son, Hudson, wasn’t jumping around as much as other toddlers his age. But his pediatrician reassured her that kids all develop at their own pace, and “he wasn’t really concerned,” she tells PEOPLE.

Then Hudson, 4, started preschool.

“His preschool teacher mentioned that he used his hands to get off the floor,” the Tuscon, Ariz., mom explained. “They have to push themselves up and then go up on their legs. And then she said he had trouble going up the stairs and not running as fast as all the other kids. So she's like, ’I would recommend going and seeing a neurologist.’ ”

<p>Melanie Sanford</p> Hudson Sanford was diagnosed with the rare disease Duchenne Muscular Dystrophy

Melanie Sanford

Hudson Sanford was diagnosed with the rare disease Duchenne Muscular Dystrophy

Sanford made an appointment right away. His blood work came back showing highly elevated CK levels.

“CK stands for creatine kinase, an enzyme that leaks out of damaged muscle,” the Muscular Dystrophy Association explains. “When elevated CK levels are found in a blood sample, it usually means muscle is being disintegrated by some abnormal process, such as a muscular dystrophy or inflammation.”

In Hudson’s case, his CK levels were “really high. It was, like in the 17,000s,” Sanford tells PEOPLE. "When it's that elevated, it’s pretty much the indicator that it was Duchenne.”

Duchenne muscular dystrophy (DMD) is one of the most severe forms of inherited muscular dystrophies,” the National Library of Medicine says. “Mutations in the dystrophin gene lead to progressive muscle fiber degeneration and weakness.”

And as Sanford tells PEOPLE, “When you Google it, it's really devastating. It's a horrible disease.”

At one of Hudson’s earliest appointments, she received dire news: “She basically said, ‘He's going to live to be 28. He's going to lose all of his ability to do everything. There's nothing you can do really, just give him steroids and go live your life.’ “

Sanford was floored. “It was terrible. I would never wish that on anybody. And this is when he was four. “

<p>Melanie Sanford</p> Hudson Sanford

Melanie Sanford

Hudson Sanford

Related: Insurance Denies Newborn Twins Life-Saving Treatment for Fatal Genetic Disorder: 'Hard to Cope'

But she refused to give up, researching therapists and treatments to help her son live.

That’s when Sanford found out about Elevidys, a new one-time gene therapy targeting the root cause of Duchenne, rather than just managing its symptoms.

There was just one problem. At the time, Elevidys was only eligible for children up to 5 years old, and Hudson was about to turn 6. And, the treatment was out of state.

As Sanford tells PEOPLE, “We flew to Texas on the 17th of August, and he got his infusion on the 18th of August, and he turned [six] on the 21st.”

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As neurologist and neuromuscular physician Dr. Diana Castro, Founder and Director of the Neurology Rare Disease Center and Neurology and Neuromuscular Care Center, explains, “Duchenne is caused by the lack of dystrophin — a protein that is essential for muscle health and function. In healthy muscles, dystrophin acts as a shock absorber, helping to stabilize muscle cells during contraction and relaxation. Without dystrophin, muscles cannot repair themselves, becoming weaker and breaking down over time."

<p>Melanie Sanford</p> Hudson Sandford was diagnosed with the rare, fatal Duchenne Muscular Dystrophy.

Melanie Sanford

Hudson Sandford was diagnosed with the rare, fatal Duchenne Muscular Dystrophy.

The way Elevidys works, Castro tells PEOPLE, "is to deliver a modified version of the dystrophin gene directly to muscle cells. This modified gene instructs the cells to make a version of dystrophin protein, which is incorporated into the muscle cell. While the treatment cannot restore muscles already lost to the disease, it aims to slow or stop further disease progression by stabilizing the muscle and preserving muscle function.”

This past summer, the Food and Drug Administration expanded approval for Elevidys, which is now available to treat all patients aged 4 years and older.

For Hudson, the results were almost immediate.

“A week after the infusion, we noticed him running faster and being able to get up off the floor quicker and kind of going up the stairs a little bit quicker, and we thought maybe it was our minds playing a trick on us, but I have videos,” Sanford tells PEOPLE.

Related: Brothers With Rare Form of Muscular Dystrophy Fear They May Lose Access to Drug That Is Improving Their Lives

<p>Melanie Sanford</p> Melanie and Phillip Sanford with their son Hudson

Melanie Sanford

Melanie and Phillip Sanford with their son Hudson

Now Hudson is thriving. He plays in a bowling league, has signed up for coach pitch baseball — and is looking forward to being Gru from the Despicable Me movies for Halloween.

“Whether it lasts five years or a lifetime, I think the decision that we made is buying him time that he wouldn't have had,” Sanford said. “Before, he could not jump with two feet. Now he can. And every time he does something, he's like, 'It's my medicine. My medicine making me stronger.' "

"It's the sweetest thing,” Sanford says.

“It changes your perspective on what's important. Every day is a gift that we've been given. Yes, some days are hard. Do I cry when I go to sleep at night? Sometimes, yes, but just when I think of how far we've come and all the people that have helped us," she tells PEOPLE.

"Every day is a gift and we're not guaranteed that any of us will be here tomorrow, so we just live our life thankful for what we're given.”

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