Those of us with Gaucher disease who know how much uncertainty, fear, and anger enzyme replacement treatment (ERT) shortages cause, REJOICE!
Researchers have found that the oral substrate reduction therapy (SRT) Cerdelga® (eliglustat) shows similar clinical results to the ERT Cerezyme® (imiglucerase).
That means we have one more option to put in our “just-in-case” medicine cabinet (figuratively speaking, of course).
Those of you who’ve never had to live through a pharmaceutical company asking you to ration or cut back on your medicine will find the report valuable, too.
Lyso-What?
Gaucher disease is the most common lysosomal storage disorder.
What does that mean?
Well, lysosomes are structures (organelles) that store enzymes created by the cell to break things down.
I’ve heard them described as “little digestion machines” or “recycling centers,” which sums them up nicely, imho. When lysosomes don’t do their job the way they should, excess products aren’t broken down. Instead, they accumulate in the cell.
What causes the lysosomes to malfunction?
In the case of Gaucher disease, it’s a mutation in the GBA gene that tells the body to make the enzyme beta-glucocerebrosidase. When there isn’t enough of the enzyme, or it doesn’t work well, a fatty substance called glucocerebroside doesn’t get digested; instead, it builds up in cells. This, in turn, can cause tissue and organ damage—most often to the spleen and liver.
Symptoms of the most common form of Gaucher, type 1, include:
- Fatigue and lack of stamina and energy
- Bone pain and reduced density (there’s an increased risk of osteoporosis)
- Increased tendency to bleed and bruise
- Low levels of blood platelets and red and white blood cells
- Loss of appetite
- Enlarged liver or spleen
ERT
As the name indicates, the most commonly used treatment for Gaucher, ERT, works by balancing a person’s own GBA levels via an IV infusion of a recombinant form of an enzyme. The infusion usually takes 1 to 2 hours and typically happens every 2 weeks.
The first ERT was approved by the U.S. Food and Drug Administration (FDA), in 1991. Currently there are 3 FDA-approved ERTs.
SRT
Substrate reduction therapies partially block the reactions necessary to create glycosphingolipids, including glucocerebroside. Rather than increasing the amount of enzymes to normal levels so the body can break down glucocerebroside, SRT lowers the amount of glycosphingolipids needing to be processed.
Going Head to Head
Now, head-to-head clinical trials between two drugs indicated for the same disease are expensive. Generally, too expensive for the pharmaceutical companies that make them.
But researchers at Sanofi Genzyme, the company that makes both Cerdelga and Cerezyme, decided to at least compile and compare the available data on the two treatment options.
The research paper, “Clinical response to eliglustat in treatment-naïve patients with Gaucher disease type 1: Post-hoc comparison to imiglucerase-treated patients enrolled in the International Collaborative Gaucher Group Gaucher Registry,” was published in Molecular Genetics and Metabolism Reports.
The researchers found, in the end, that it seems as if the two treatments can have similar clinical results. And that’s good news!
The more treatment options there are for people living with Gaucher disease, the better!
