– The mother and father watched as their 16-year-old daughter ate her pork chop and green beans across the kitchen table of their suburban Mount Prospect home, grateful each time she swallowed without a struggle.

Hayley Koujaian sang a few lyrics of her favorite song. “We’re all in this toge-e-ether,” the theme from “High School Musical,” a movie she loved as a little girl, before anyone could tell she was sick.

Hayley has a rare genetic disorder called Niemann-Pick Disease Type C, often dubbed childhood Alzheimer’s, though it’s not the same disease. Memory, speech and mobility fade. It gets harder to eat and drink unaided. There is no treatment approved by the FDA, and young children with the disorder typically don’t live past their teens.

“We all knew what the outcome was going to be if the disease progressed,” said her father, Harry Koujaian. “There is only one outcome. That’s why we were so desperate.”

Yet the family has found hope in a promising experimental drug — and the local physician who helped them gain access. Every two weeks, Dr. Elizabeth Berry-Kravis injects a treatment called cyclodextrin into Hayley via a spinal tap at Rush University Medical Center. Hayley is one of roughly 40 U.S. patients using the investigational drug, hoping for future FDA approval.

Berry-Kravis, a pediatric neurologist, said there’s initial evidence the injections could be staving off the disease’s progression. Some skills even appear to be improving.

Before starting treatment a little more than two years ago, Hayley was functioning at the level of an 18-month-old. Now her abilities closer match a 2½- or 3-year-old. Swallowing is much easier. Her gait is smoother, and she’s less apt to fall.

While the drug is still in clinical trials, it has significantly extended the lives of mice and cats with the disorder compared to those untreated.

The Koujaians wonder whether it could be extending Hayley’s life, too.

Hayley was born Aug. 10, 1999, a chubby-cheeked baby with heart-shaped lips and no hint of any abnormality. In first grade, she mysteriously began falling behind.

Later, Hayley began having seizures. Medication after medication failed, and, at 11 she had brain surgery and her tissue was sent to a pathologist for testing.

Six months and a litany of tests later, the Koujaians got the devastating diagnosis: Niemann-Pick Type C, a fatal disease often appearing in children where naturally produced cholesterol accumulates and becomes toxic. There are about 500 cases diagnosed internationally.

Another mom told them about cyclodextrin, which appeared to help her twin daughters. The National Institutes of Health had just begun an exploratory trial. The Koujaians jumped at the chance for Hayley to join the study, but she was found ineligible because of her seizures.

The only other option was to find a physician to file a compassionate-use request with the FDA. They had just started seeing a new pediatric neurologist, Berry-Kravis, who found the most recent research for cyclodextrin so compelling, she wanted to give it a try.

After Berry-Kravis was approved to treat Hayley, others with the disorder started trickling in to get the injections, too. She is now administering cyclodextrin to 12 patients, some traveling from as far as Minnesota and Texas.

While questions still linger — will the drug work long term? What’s the optimal dose? — at least now, “There is hope,” Gail Koujaian said.