What Is Enzyme Replacement Therapy?
Enzyme replacement therapy (ERT) involves intravenous (IV) infusions to correct the underlying enzyme deficiency that causes symptoms of Gaucher disease (pronounced go-SHAY). In particular, a common use of enzyme replacement therapy is for lysosomal storage disease treatment. If you or a loved one has Gaucher disease type 1 or 3, ERT can minimize symptoms and prevent permanent damage to the body.
How Does Enzyme Replacement Therapy Work?
ERT balances low levels of glucocerebrosidase (GCase) enzyme with a modified version of the enzyme. This enzyme breaks down glucocerebroside, the fatty chemical that accumulates in the body of patients with Gaucher disease. (This compensates for the missing enzyme, which is why the therapy is called enzyme replacement.) Patients receive ERT via IV infusion, which usually takes 1 to 2 hours. The U.S. Food and Drug Administration (FDA) approved the first ERT in 1991.
Patients typically need an ERT infusion every 2 weeks, depending on the individual. You can receive ERT at an infusion center, a Gaucher disease treatment center or at home, and each setting has benefits and drawbacks.
Infusion centers
Many patients receive ERT at infusion centers, which are medical facilities specializing in IV infusions. Patients travel to the infusion center where they wait for medical staff to prepare the medication. The process can take an hour or more, although some centers will start the preparation when patients are on their way.
Many people find the travel and waiting associated with infusion centers time-consuming and inconvenient. It can also be difficult for children, who often must miss activities and events to receive infusions. Some infusion centers also cannot care for children. Even so, many patients prefer infusion centers because they are familiar, insurance covers their ERT treatment and they enjoy good relationships with the staff.
Gaucher disease treatment centers
Patients may also receive ERT infusions at some hospitals and physicians’ offices. This allows Gaucher specialists to more easily monitor key health markers and adjust your medication dosage.
You will still need to travel to your appointment and wait for medication to be prepared if you go to a Gaucher disease treatment center. However, patients may find it more convenient if they can combine appointments and may prefer having experts on hand. You can locate one of these specialized facilities with our Gaucher disease treatment finder.
Home infusions
Some patients prefer getting ERT infusions at home with the help of a home health nurse. The nurse prepares the medication and assists with the IV, so you can receive ERT treatment in the comfort of your own home.
The main benefit of home infusions is that you don’t have to travel or spend time waiting at infusion centers. Home infusions can improve your quality of life and offer children a more normal childhood.
Drawbacks include not having extra staff on hand if complications occur, like if the nurse has trouble inserting the IV. While getting insurance to cover home infusions can be a hurdle, pharmaceutical case managers can help you navigate your coverage. Learn more about financial support available for patients with Gaucher disease.
Enzyme Replacement Therapy Drugs for Gaucher Disease
The FDA has approved ERT treatments for Gaucher Disease including the following enzyme replacement therapy drugs:
Talk to a Gaucher specialist to find out which enzyme replacement therapy drug and treatment option is right for you. You can learn more about how to find a specialist with our Gaucher disease treatment finder.
Oral Treatment for Gaucher Disease
In addition to ERT infusion drugs, oral substrate reduction therapy (SRT) is also available for treating Gaucher disease. This medication works differently from ERT, and only certain patients can receive it.
Working with a Gaucher specialist is key to determining which treatment is right for you. Learn more about substrate reduction therapy (oral medication) for Gaucher disease.
Advantages and Disadvantages of Enzyme Replacement Therapy
When deciding between ERT and SRT, it’s important to weigh the pros and cons of taking ERT. Pros of using ERT to treat Gaucher disease include:
- Fewer side effects: Compared to SRT, ERT has fewer negative side effects.
- Longer drug history: SRT is newer than ERT, and some patients prefer taking medications that have been on the market for a longer period of time.
- Wider availability: Unlike SRT, ERT is available for both children and adults, including pregnant and breastfeeding women.
Cons of taking ERT as a Gaucher disease treatment include:
- Inconvenience: Many people find taking an SRT pill is more convenient than having to schedule IV infusions.
- More invasive: ERT requires an IV or a port, a device installed under the skin for repeat use in delivering IV medications. IV access can be a problem for some patients, and the long-term safety of ports over many years of therapy is a potential concern.
- Ups and downs: Some patients feel best right after an infusion and often feel fatigued when they are due for an infusion. Compared to ERT, SRT provides a more consistent dose.
Paying for Enzyme Replacement Therapy
ERT can be very expensive, totaling up to $200,000 or more each year. Insurance may cover most of this cost, and resources are available if you need help paying for ERT treatments.
These resources include:
- Pharmaceutical companies: Dedicated case managers at pharmaceutical companies can help you navigate your insurance coverage if you have received a Gaucher disease diagnosis.
- CARE and CARE+PLUS Programs: The National Gaucher Foundation offers financial grants for people with Gaucher disease and their families. The CARE Program [care-program] provides assistance with health insurance premiums, while the CARE+PLUS Program can help with genetic testing and other medical expenses not covered by insurance.
- Nonprofits: Organizations like the Patient Access Network, Accessia Health and NeedyMeds may also be able to help you with the cost of medication.
Learn more about financial support for help paying for Gaucher disease treatment.
Fetal Therapy Clinical Trial for Gaucher Disease Types 2 and 3
University of California, San Francisco (UCSF) pediatric surgeon and researcher Dr. Tippi MacKenzie is the lead investigator in a fetal therapy clinical trial, which involves giving medication to a fetus within the woman’s uterus. Fetal therapy is not a new technique, but the UCSF trial is the first time anyone has used it to deliver enzymes.
The National Institutes of Health is sponsoring the clinical trial, and anyone who is eligible can apply.
“All medical costs for the procedure are covered, and so are travel costs,” says Dr. MacKenzie. “We’re treating all trial participants here at UCSF, so we know we can offer the best care and have the most experienced team involved.”
For more information on the trial, click here.
