麻豆传媒

TORONTO - Created to treat a disease within just one person, and named after the little girl it was developed for, a drug thought to be the very first custom medication is here -- and it鈥檚 bringing up questions for scientists about the ethics and efficacy of personalized medicine.

Eight-year-old Mila is the world鈥檚 only recipient of the drug 鈥渕ilasen鈥� -- a groundbreaking treatment created specifically to combat her rare neurodegenerative disease, and paid for by a massive crowdfunding effort her parents started.

A in the New England Journal of Medicine called the drug 鈥渁n example of individualized genomic medicine,鈥� and outlined the journey researchers took in order to develop milasen.

According to the paper, Mila鈥檚 parents first became concerned when she was three years old and they noticed her right foot beginning to turn inward. As the years went on, her condition grew more pronounced: she needed to pull books much closer to her face when she was four, and at five she was showing signs of regressing in her language and social skills, and was also growing clumsier.

The tipping point came when Mila was six. She was hospitalized after 鈥渢he rapid development of loss of vision, frequent falls, dysarthria, and dysphagia,鈥� the research paper said.

Numerous tests later, a diagnosis was reached: Mila had Batten鈥檚 disease.

Batten鈥檚 disease is a rare recessive condition that affects sight and the central nervous system. It causes seizures and cognitive impairment, and eventually leads to early death in children and young adults.

No cure has been discovered yet.

鈥淥ur hearts stopped,鈥� reads a post by Mila鈥檚 parents on the . 鈥淥ur bodies went limp.鈥�

The family was devastated by the diagnosis, but refused to give up. They decided to start raising money to fund research into treatments for Mila. They started a GoFundMe, and then a website dedicated to their daughter.

A linked to their website shows the fundraising to be at just under $1 million, but according to , over the years since Mila鈥檚 disease was diagnosed, the family has raised around $3 million for the research efforts.

The danger of Batten鈥檚 disease is that the problem is in the patient鈥檚 DNA itself. In Mila鈥檚 DNA, there鈥檚 a misplaced piece of genetic code making it impossible to manufacture an important protein correctly. The incomplete protein cannot be broken down properly in the lysosomes of cells, leading to a buildup of material that eventually kills the cell.

Milasen, the drug created to combat this by a team of researchers at the Boston Children鈥檚 Hospital, works by splicing in a new genetic code that makes the pattern of protein building work again.

Mila鈥檚 condition worsened over the year it took to develop the drug. When she was seven, she had so much trouble swallowing that she had to have a feeding tube inserted. She had lost the ability to make discernable words, and had 15 to 30 seizures per day, the research paper said.

Batten鈥檚 disease has multiple variants -- making the need for individualized research and treatment even more prevalent -- and Mila鈥檚 variant is called CLN7. The research paper said that in the largest published case study of CLN7 patients, seven patients died when they were just a little over 11 years old.

Considering how fast Mila鈥檚 disease seemed to be progressing, researchers filed for permission from the Food and Drug Association (FDA) to start testing the drug on rats to ensure that there were no harmful side effects.

When they were sure it was safe, they gave Mila her first dose through a spinal tap.

That was in 2018. Since then, according to the research paper, Mila is now only experiencing zero to 20 seizures a day, and the duration of them has decreased to less than a minute.

In a this week, she reported that many of Mila鈥檚 disease symptoms 鈥渉ave stabilized, even improved,鈥� going on to describe how she has regained more of her motor skills, such as the ability to take steps with some assistance, and feel objects on her own.

However, she still has lasting neurological damage. And whether or not she will survive the disease is still unknown.

Rare diseases as a whole affect around 30 million people in the U.S. alone, according to the research paper. There are more than 7,000 distinct conditions that qualify as 鈥渞are,鈥� though the number changes depending on how you define it.

An in the New England Journal of Medicine to accompany the research paper on milasen warned that the field of personalized medicine introduced a number of problems and questions.

鈥淲hat type of evidence is needed before exposing a human to a new drug?鈥� the piece asked. 鈥淗ow should the urgency of the patient鈥檚 situation or the number of people who could ultimately be treated affect the decision-making process?鈥�

How doctors could accurately measure the effectiveness of a drug aimed at one person was also a new aspect that would have to be contended with, according to the editorial. What if a perceived improvement in a patient is more placebo than anything else?

According to CTV鈥檚 Science and Technology Specialist Dan Riskin, 鈥淵ou need a big sample size to understand these things about drugs.鈥� That鈥檚 not possible with individualized treatments, he said.

When the development of a personalized drug is so expensive, these questions are more important than ever.

鈥淭he economic side is obviously the first thing that comes to my mind because it seems totally unfair on the surface,鈥� Riskin pointed out. 鈥淲hat that means is the more means you have, the better off your kid's going to be. But most people don't have those means. And so if this is the path forward for medicine, it puts a big question mark on what happens to the 99 per cent.鈥�

Although crowdfunding can be one pathway to afford specialized medical treatment, not every case will manage to catch attention the way Mila鈥檚 did and be able to have traction.

From a purely scientific standpoint, the implications of milasen are exciting, Riskin acknowledged.

鈥淭his is a logical extension of where the science is right now. If we can figure out individually what your DNA says, we can figure (out) individually what your DNA is doing wrong and we should be able to individually fix what's going wrong.鈥�

But Riskin doesn鈥檛 think it鈥檚 likely that this type of drug development would come to Canada any time soon, due to our public health care system.

鈥淭his just goes right back to that debate that鈥檚 been going on in Canada for decades about 鈥� if any Canadian is allowed to have (a type of treatment), then every Canadian should have it.鈥�

The research paper on milasen acknowledged that although Mila has seen improvements, the drug has not solved everything: tests done seven months after the first treatment showed she was still experiencing a continued loss of brain volume.

Her family remains hopeful. Not just for Mila, but for the idea that treatments like milasen could 鈥減ave this path for many more children like Mila across hundreds of rare diseases.鈥�

Their fundraising may have started out as just for their daughter, but now the website -- Mila's Miracle Foundation -- provides grant funding to scientists studying Batten鈥檚 disease and developing other gene therapies, aiming to close that economic gap to access personalized medicine.