The presence of severe complications of Gaucher disease type 1 (GD1) at the time a patient starts treatment has steadily dropped since the introduction of enzyme replacement therapy with Cerezyme (imiglucerase) in 1991.
After analyzing clinical characteristics of symptomatic GD1 patients in the U.S. from 1991 to 2009, researchers from the Yale University School of Medicine concluded that an optimal standard of care for GD1 has been established in the U.S. They also noted that the changing features of GD1 patients call for a revision of treatment guidelines and goals.
The study, “Transformation in Pre-treatment Manifestations of Gaucher Disease Type 1 during Two Decades of Alglucerase/Imiglucerase Enzyme Replacement Therapy in the International Collaborative Gaucher Group (ICGG) Registry” was published in the American Journal of Hematology.
Physicians and researchers have noted that more severe complications of Gaucher disease, including removal of the spleen and bone and blood problems, appear to be rarer in patients starting treatment now than when enzyme replacement treatment was introduced in 1991 and then approved in 1994. But until this study, researchers had not previously attempted to confirm this.
The Yale research team turned to the International Collaborative Gaucher Group Gaucher Registry for answers.
The team divided patients into age groups and four-year intervals — 1991–95, 1996–2000, 2001–05, and 2006–09 — according to when they first started enzyme replacement treatment. Data showed that treatment was initiated earlier in each consecutive era.
Of the 1,427 patients included in the study in the U.S., who started treatment across all four intervals, 25.2% had removed their spleen before starting Cerezyme treatment. Researchers noted that when Cerezyme was introduced, splenectomy rates drastically dropped.
Among adults who started treatment between 1991 and 1995, more than 40% had a splenectomy. In children, the number was about 20%. In each successive five–year period, rates dropped in both adults and children. In the latest period, from 2006 to 2009, the practice was virtually absent among children.
The data also showed that patients who had their spleen removed more often had bone manifestations of disease — including bone crisis, ischemic bone events, and bone pain — compared to those with an intact spleen.
But rates of bone problems in those with an intact spleen also dropped with each successive period.
Meanwhile, analyses showed that the time from diagnosis to initiation of Cerezyme treatment became increasingly shorter with each period. This was particularly true for children with more severe disease, researchers found.
“Together, these findings suggest that since the introduction of imiglucerase ERT, optimal standard of care has become established in the US to prevent destructive complications of GD1,” the authors concluded.