Doctors can’t cure Pompe disease. But treatment can help babies, children, and adults with the condition live longer, and often with fewer complications.
In 2006, the FDA approved the first treatment for Pompe disease. It consists of regular IV infusions of a man-made enzyme called alglucosidase alfa. The drug does the job of an enzyme in your body that doesn’t work correctly when you have Pompe disease. This process, known as enzyme replacement therapy (ERT), is still the only treatment approved for the condition.
Before ERT was available, newborns diagnosed with the classic infantile form of Pompe disease rarely lived longer than a year.
“Without ERT, babies with infantile Pompe disease have a progressive thickening of the heart muscle and develop significant skeletal muscle weakness that leads to death in the first year of life,” says Priya Sunil Kishnani, MD, a pediatrician and clinical and biochemical geneticist at Duke University Medical Center.
The disease also damages skeletal muscles and the muscles you need to breathe.
“Babies who don’t receive ERT become so weak, they lose any previously achieved motor milestones, such as the ability to roll over,” says Kishnani, the Chen family distinguished professor of pediatrics at Duke.
The infusion therapy has dramatically improved the outlook for these children. The first babies treated with ERT are now in their 20s. ERT also helps children and adults diagnosed with late-onset Pompe disease.
“There are a lot of unknowns and anxiety for families with Pompe disease, but I would like them to know the field is evolving rapidly and there is much to be hopeful about,” Kishnani says.
It’s important to note that ERT is only one part of overall care, she says. People with Pompe disease need treatment from multiple health care professionals for the best quality of life.
“ERT is lifesaving, but it’s the overall management of the disease, which includes the right nutrition, physical therapy, and other specialty care, that really impacts the outcome,” she says.
A clinical geneticist is often the main doctor who manages care for Pompe disease. Other specialists treat complications the condition can cause.
Your treatment team may include:
CardiologistsPulmonologists GastroenterologistsNutritionistsPhysical therapistsOccupational therapistsSpeech therapists“Multidisciplinary support gives people with Pompe a chance for a much better overall outcome,” Kishnani says.
Here’s what treatment for you or your child may include.
Enzyme replacement therapy (ERT)
ERT replaces an enzyme that your body can’t make enough of, or can’t make at all, when you have Pompe disease.
Without this enzyme, called acid alpha-glucosidase (GAA), your body can’t break down a sugar molecule called glycogen. So glycogen builds up your cells, especially muscle cells. There, it damages your tissues and leads to muscle weakness and wasting.
ERT for Pompe disease involves regular, lifelong infusions of alglucosidase alfa. This drug, sold as Lumizyme in the United States, is a man-made version of the natural GAA enzyme. It does the job that the enzyme would do if your body made enough. That stops glycogen from building up in your tissues and muscles.
You or your child will probably get infusions every other week, though some people get them weekly. A surgeon may place a central line, a port doctors use to deliver the infusions, that stays in place long-term. This can make the treatments easier and more comfortable. Each session lasts several hours (up to 6 hours for some people).
You or your child can get ERT in an infusion center and sometimes in your home.
“ERT can help reverse heart damage and prevent the need for breathing support from a ventilator, even in babies at the most severe end of the classic infantile Pompe disease spectrum,” Kishnani says.
Start this therapy as early as possible. If muscles you need for breathing or movement have already been damaged, ERT can’t usually reverse it.
“In babies with classic infantile Pompe disease, we try to start ERT within the first few days of life,” Kishnani says. “Even short delays can cost these babies the ability to walk, for example.”
If you or your child has late-onset Pompe disease, your doctor will do regular tests to look for any symptoms. This will help them decide when to start ERT.
Medications that act on the immune system
If your baby has classic infantile Pompe disease, your doctor will do tests to find their cross-reactive immunologic material (CRIM) status. CRIM-negative babies are at high risk for an antibody reaction to ERT, which stops the therapy from working.
A treatment called immune tolerance induction (ITI) can prevent this response.
“At Duke, we give CRIM-negative babies a 5-week short course of immune-modulating drugs,” Kishnani says. “This treatment tricks the immune system into recognizing ERT as ‘self’ [vs. a foreign substance], and the babies develop an immune tolerance to the enzyme therapy.”
Drugs used for ITI, which usually starts at the same time as ERT, include:
RituximabMethotrexateIntravenous immunoglobulin, or IVIG Occupational and physical therapy
Occupational therapists can teach you or your child skills to help with daily self-care and tasks. If needed, they can help you learn to use canes or other assistive devices.
Physical therapists can help you or your baby lessen muscle weakness and build strength. For Ryan Colburn, physical therapy — and the physical activity it helps him do — has been a crucial treatment for his late-onset Pompe disease.
Colburn, now 37, got the diagnosis 6 years ago. He sees a physical therapist weekly and does a daily physical activity program at home.
“For me, physical activity is the most important part of treatment if you want to change or maintain your physical capability or levels of independence,” says Colburn, who lives in Los Angeles.
Speech therapy
Pompe disease can weaken the muscles of your face and tongue and affect your speech. A speech therapist works with you or your child to improve speech and language skills.
Nutritional therapy
The disease can damage muscles you need to chew and swallow. Babies with Pompe disease may need a doctor to place a feeding tube to give them the nutrition they need to grow. Older children and adults with Pompe might also have swallowing problems. They don’t usually need feeding tubes but may benefit from special diets.
Treatments for other complications
Cardiologists will regularly check you or your baby for heart problems and prescribe any needed treatments.
You or your child may also need regular visits with a pulmonologist, who’ll look for breathing problems. If needed, they can use ventilators to help you breathe.
Your doctor will also do regular tests to check your or your baby’s motor skills, hearing, and other functions. This helps them find and treat problems as soon as they appear.
Your role in care
Colburn takes a very active role in his own care.
“The single most important thing I’ve done is get educated about Pompe,” he says. “It has built my confidence and comfort with managing my day-to-day life with the disease.”
For the best care, Kishnani says, “you’ve got to be a good self-advocate and work with your treating physician to ensure that he or she understands Pompe disease and your needs.”
Source : WebMD