At the recent EWGGD meeting in Paris, Shire announced the results of a head to head trial between VPRIV and Cerazyme and the effect that each had on Gaucher related bone disease. A copy of the full press release is below. Whilst the results of this trial are extremely encouraging it is important to note that it appears the two groups of patients involved in the trial were not well matched in relation to bone mineral density (the patients treated with VPRIV having the more severe bone disease) and it is a common finding in general that patients with the most deviation from normal will improve the most and that patients with normal findings will not improve at all.
The data presented demonstrate that VPRIV improves Gaucher-related bone disease by a sustained increase in bone mineral density (BMD). BMD refers to the measurement of mineral matter per square centimeter of bone measured by Z-scores. Z-scores allow for a comparison of a patient’s BMD to age- and sex-matched normalized scores in populations without Gaucher disease. In Gaucher disease patients, BMD is generally reduced compared to individuals without Gaucher disease, often resulting in lower Z-scores. Measuring BMD can help to quantify the impact of Gaucher disease on the patient’s bone and can help identify the potential benefits of treatment in improving Gaucher-related bone disease.
“Many type 1 Gaucher disease patients experience bone abnormalities,” said Professor Ari Zimran, Shaare Zedek Medical Center, Hebrew University and Hadassah Medical School, Jerusalem, Israel. “These study results show that VPRIV is effective in treating selected markers of Gaucher-related bone disease, allowing these patients to achieve an important therapeutic goal quickly.”
Results from a head-to-head Phase III study (HGT-GCB-039) of VPRIV and Cerezyme, and follow-on extension trial (HGT-GCB-044) of VPRIV, demonstrate a statistically significant improvement in lumbar spine (LS) BMD in Gaucher patients starting at nine months of treatment with VPRIV (P<0.05). Patients participating in the study were administered 60 U/kg every other week of either VPRIV or Cerezyme for nine months as part of the HGT-GCB-039 study. All patients, including those who received Cerezyme, subsequently received 60 U/kg every other week of VPRIV for an additional 15 months in the extension trial (HGT-GCB-044).
Clinically and statistically significant improvement from baseline in mean LS Z-score was seen at nine months of treatment with VPRIV, but not in the cohort of patients treated with Cerezyme. BMD, evaluated as an exploratory endpoint in the Phase III and extension studies, was measured by dual-energy x-ray absorptiometry (DEXA scan). Median LS Z-scores at baseline were -1.46 (-3.50, 0.98) in patients treated with VPRIV, and -0.86 (-2.17, 2.02) in
patients treated with Cerezyme. Mean changes from baseline in LS Z-scores at nine months were 0.33 (0.10, 0.55) and 0.06 (-0.22, 0.34), respectively. Following an additional 15 months of treatment, mean change in LS Z-scores improved to 0.64 (0.22, 1.06) for patients initially treated with VPRIV and improved to 0.54 (0.21, 0.87) for patients who switched to VPRIV from Cerezyme at nine months. Femoral neck changes from baseline in both cohorts were
non-significant (P>0.05) at either nine or 24 months. Analysis presented at EWGGD excluded data from five patients on concomitant bisphosphonates, although similar results were observed when data from these patients were included. The safety events observed in this study were similar to those seen historically in patients treated with VPRIV.
Shire presented additional data showing how VPRIV significantly improved Gaucher-related bone disease in patients at EWGGD:
■Bone Parameters in Adults with Type 1 Gaucher Disease Treated with Velaglucerase Alfa in Trial TKT025 and the Extension Study: Focus on the Bone Marrow Burden Scores Over 7 Years: encore presentation
■Bone Mineral Density in Adults with Type 1 Gaucher Disease Receiving Velaglucerase Alfa 60 U/kg Every Other Week: 2-Year Results (HGT-GCB-032/039/044)
VPRIV is made in a human cell line using Shire’s gene activation technology. The enzyme produced has the exact human amino acid sequence as that found in the naturally occurring human enzyme. VPRIV is used for the long-term treatment of patients with type 1 Gaucher disease. VPRIV is approved in 40 countries globally, including the US, the European Union member states, and Israel, and is for patients previously treated for type 1 Gaucher disease or those who are treatment-naive.
VPRIV Important Safety Information
The most serious adverse reactions seen with VPRIV were hypersensitivity reactions. Infusion-related reactions were the most commonly observed adverse reactions in patients treated with VPRIV in clinical studies. The most commonly observed symptoms of infusion-related reactions were: headache, dizziness, low or high blood pressure, nausea, tiredness and weakness, and fever. Generally the infusion-related reactions were mild and, in treatment-
naïve patients, onset occurred mostly during the first 6 months of treatment and tended to occur less frequently with time.
All adult side effects of VPRIV are considered relevant to children (ages 4 to 17 years). Side effects more commonly seen in children compared with adult patients included: upper respiratory tract infection, rash, aPTT prolonged, and fever. The safety of VPRIV has not been established in patients younger than 4 years of age.
As with all therapeutic proteins, there is a potential for immunogenicity. In the clinical studies 1 of 54 treatment-naïve patients treated with VPRIV developed IgG class antibodies. It is unknown if the presence of IgG antibodies to VPRIV is associated with a higher risk of infusion reactions.