Spinal Muscular Atrophy, or SMA, is a deadly inherited disease. It affects about 1 of 10,000 babies, but it tends to be fatal—it’s the number one genetic cause of death for infants, and most of them die by age 3.
There is no approved treatment for SMA, and as a result, it’s become a big target for several drugmakers, among them Carlsbad, CA-based Isis Pharmaceuticals (NASDAQ: [[ticker:ISIS]]). But others are trying, too, like a Dallas biotech named AveXis, which last week raised $10 million in venture cash to fund clinical trials for its own experimental therapy.
SMA is caused by a mutation in the motor neuron gene 1, which results in an attack on the central nervous system, taking away the ability to walk, eat, or breathe. In healthy people, the neuron produces a protein that is critical to the function of nerves that control muscles. Without it, these nerve cells die, leading to debilitating, and fatal, muscle weakness.
AveXis is trying to treat the disease with gene therapy, a process by which healthy genes are transported, typically by a virus, into cells to treat disease. AveXis’s gene therapy candidate, ChariSMA, for instance, is supposed to provide patients with a functional SMN gene. The therapy is delivered via a specific type of adeno-associated virus, or AAV, which CEO and co-founder John Carbona says can cross the blood-brain barrier.
“They are born with X number of motor neurons and every day they start to lose them,” he says of SMA-afflicted infants. “We use their own genes to stop the destruction, maintain the existing [genes], and prevent further loss.”
AveXis is focusing on treating SMA 1, which occurs in babies from birth to six months of age. In May 2014, the biotech dosed the first patient in it’s first trial, a now 1-year-old who is still alive, Carbona says. While a single example, that’s significant because about half of newborns diagnosed with SMA typically die at 10 months of age. AveXis has enrolled four patients, and evaluating the safety and efficacy of the therapy.
Of the four children are in the trial, one is getting a low dose, two are receiving twice that dose, the fourth is getting the highest dose of the drug. This highest dose “completely rescued the mice … that were supposed to die in two weeks” in animal studies, Carbona says.
The funds from the group of investors, led by Deerfield Management in New York and Roche Venture Fund (the venture arm of Roche), will be used for at least one additional trial AveXis is running with the help of Nationwide Children’s Hospital in Columbus, OH. Children
