That was the situation faced by the Harting family of El Granada, California, in 2013, soon after their baby girl, Zoe, was found to have spinal muscular atrophy type 1. The genetic disease interferes with the body's ability to make an essential protein called survival motor neuron. Without enough of the protein, nerves that carry signals from the spinal cord to the muscles degenerate. Patients' muscles atrophy to the point that they can't move, swallow, or breathe. In the past, most affected children died before they turned 2.
When Zoe was diagnosed with SMA-1 in 2013, her parents, John and Eliza Harting, were initially told that there was nothing that could be done to slow the progression of the disease. But both of them work in scientific research, and they didn't want to give up. As I explain in a story published today, they learned from Stanford pediatric neurologist John Day, MD, PhD, about a clinical trial for an experimental drug called nusinersen:
The drug had already been given to older children with a milder form of spinal muscular atrophy to test its safety, but physicians needed to try it in babies with SMA-1 to discern if it caused a measurable improvement in their symptoms. Day asked the Hartings to let Zoe be the first.
John Harting read some of the scientific papers explaining how nusinersen was expected to function. 'What I read suggested it was a good bet, and the only one available at the time,' he said. 'We decided we had to take this chance.'
It took a long time -- more than a year -- for Zoe's doctors and her family to feel certain that nusinersen was helping. Zoe had already been significantly weakened by her disease before she began to receive the drug, and the process of gaining strength was slow and gradual, with many setbacks. But today she is a happy 4-year-old who can talk, yell, scoot around in a motorized wheelchair, play catch with her dad and, as shown in the photo above, goof around at home with her family.
Today, The Lancet publishes a paper describing phase-2 trial data from a total of 20 children, including Zoe, that gives strong evidence that nusinersen works. And a phase-3 trial of the drug was halted earlier than planned this year when it became clear that children receiving the drug were doing much better than those who did not get it. In addition, the Food and Drug Administration is expected to approve the new drug application for nusinersen within the next two months. Again, from the story:
'This drug completely turns things around for SMA,' Day said. 'It’s a definite game-changer.' An even larger discovery is that drugs with the same mechanism of action may help treat other genetic diseases, he added. Nusinersen is an antisense oligonucleotide, which works by sticking to a specific piece of genetic material. Trials of antisense oligonucleotide drugs are now underway for other neurological diseases, including myotonic dystrophy, Huntington’s disease and amyotrophic lateral sclerosis.
Children with SMA-1 who receive nusinersen will continue to need specialized medical care and supports such as physical, occupational, speech and swallowing therapies, Day said. But if babies start receiving the drug early, before they become symptomatic, "we can be optimistic that it will effectively cure them," he said.
Previously: Study suggests new strategy for spinal muscular atrophy, Drug companies turning their attention to rare diseases and Coaxing muscles to heal with less scarring could improve aging, muscular dystrophy treatments
Photo courtesy of the Harting family