DENTON, Texas—Surrounded by festive balloons, tasty Tex-Mex appetizers, and plastic cups of champagne, a Colombian-born pediatric neurologist and her Israeli husband recently inaugurated the nation’s first CureDuchenne-funded clinic in this suburb of Dallas, Texas.
Diana Castro, MD, and Shai Mazouri, MD, hosted nearly 100 people at a March 19, 2023, party to celebrate the opening of their Neurology & Neuromuscular Care Center here. The 3600-square-foot facility will cater largely to Hispanic families—regardless of their insurance or US immigration status—who are affected by Duchenne muscular dystrophy (DMD) or spinal muscular atrophy (SMA).
The clinic is funded by a 3-year, $900,000 grant from CureDuchenne, a nonprofit advocacy organization aimed at finding—and funding—a cure for the as-yet incurable disease.
Dr. Castro said 18% of the roughly 30 million residents of Texas lack health insurance, giving the Lone Star State the nation’s highest percentage of uninsured residents, with Dallas being the second least-insured metropolitan area in the country. Large racial disparities also exist in Texas, she said; nearly 38% of Hispanic individuals are uninsured, more than double the state average.
“In Texas, they don’t give much importance to health, and definitely not to rare diseases,” she told Rare Disease Advisor. “The biggest problem is that here, there aren’t enough neuromuscular specialists interested in conditions like Duchenne or SMA because they’re so busy with [amyotrophic lateral sclerosis (ALS)] and other things. Yet our patients are living way longer than before, and we don’t have adult specialists with the time or desire to care for them once they reach 18 or 21 and have to transition out of the pediatric system.”
Dr. Castro said that 30% of the families she sees are uninsured, and that 45% are on Medicaid, which is not accepted at all care centers, but will be accepted at the CureDuchenne Clinic.
“Insurance is a big issue. If you have private insurance, you can find a private doctor. But if you’re on Medicaid, you’ll have to go to a county hospital whose residents have never seen Duchenne before,” said Dr. Castro, a board-certified neurologist and neuromuscular physician who has conducted multiple clinical research trials in SMA, DMD, and Charcot-Marie-Tooth (CMT) disease, among other conditions. “Our ultimate goal is to help all patients to the best of our ability—especially the most vulnerable and underserved populations.”
Equipped to Administer Gene Therapy
Dr. Castro said she had wanted to be a doctor since the age of 5. She and her husband met when both were residents of New York’s Beth Israel Medical Center; the couple resettled in Dallas in 2008 and got married the following year.
Their clinic, located on the ground floor of a professional medical building, has 6 rooms—3 of them clinics and 3 infusion and research rooms. Its walls are decorated with colorful children’s drawings and inspirational messages like “Cherish every memory. Love every moment. Embrace every possibility.”
The CureDuchenne Clinic opened for research November 1, 2022, and for clinical use January 9, 2023. Its staff is equipped to administer infusions of nusinersen (Spinraza®) as well as the gene therapy treatment onasemnogene abeparvovec-xioi (Zolgensma®), both for SMA. It also provides neurology, cardiology, pulmonology, nutrition, physical therapy, durable medical equipment, diagnostics, and chest radiography for both pediatric and adult patients.
The inauguration of the Denton facility coincided with the Muscular Dystrophy Association’s 2023 Clinical & Scientific Conference in Dallas, just 25 miles away. At that conference, one of the key topics of conversation was the expected US approval on May 29, 2023, of SRP-9001 (delandistrogene moxeparvovec)—developed by Sarepta Therapeutics as the first-ever gene therapy to treat Duchenne. The new drug is expected to retail for at least $4 million.
“We’re all excited because we have these new therapies, but we’re forgetting something,” she cautioned. “Now that these patients will live longer and longer, who’s going to take care of them? And who will be able to get those medications when they cost millions of dollars?”
Dr. Castro noted that 14% of patients with Duchenne will not be eligible for the Sarepta gene therapy because they are positive for antibodies. She said many of her patients will benefit from the therapy if it is approved for boys 4 to 7 years old, but insurance companies won’t allow treatments to begin until the end of this year.
Assisting Patients Regardless of Immigration Status
One of the biggest concerns, she noted, is medical care for undocumented immigrants from Mexico, Guatemala, Honduras and other Spanish-speaking countries once they cross the border into Texas.
“They’re afraid to find care because they might be deported. So we’re very clear in telling them, ‘we’ll take you with insurance, without insurance, with papers, without papers,’” she said, estimating that 30%-35% of the parents of boys with Duchenne she sees are in the US illegally.
“One of my patients is a boy from Honduras. His mom had to carry him pretty much everywhere because they didn’t have a wheelchair,” she recalled. “It’s very scary for these families. They will never answer your calls because they’re afraid. So over the years, I found out that text messaging is the perfect way to communicate with them.”
Luisa Leal is founder and CEO of The Akari Foundation, a San Antonio, Texas‑based nonprofit organization that advocates on behalf of Spanish‑speaking families affected by Duchenne muscular dystrophy.
“I was undocumented for 24 years in this country, so I know what it takes. We have to work extra hard—especially right now,” said Leal, who attended the inauguration of Dr. Castro’s clinic. “I speak English, but with a heavy accent, and I still have problems because of that.”
Leal, born and raised in the Mexican border town of Nuevo Laredo, said that at present, only 3 clinical trials for Duchenne are underway in all of Mexico—a country of nearly 130 million.
“In the United States, we have more access to digital resources. In Mexico, it’s hard to get numbers,” she said. “In Mexico, only 7 rare diseases are recognized, and Duchenne is not among them. We still have a lot of work to do.”