Booster-effect with velaglucerase alfa in patients with Gaucher disease switched from long-term imiglucerase therapy: Early Access Program results from Jerusalem

BackgroundDecreased spleen and liver volumes and increased hemoglobin levels and platelet counts usually occur with enzyme replacement therapy (ERT) in symptomatic patients with Gaucher disease. Because of decreased supply of imiglucerase, an FDA-approved Early Access Program (EAP) allowed use of a new, pre-licensed ERT, velaglucerase alfa. This report provides safety and efficacy findings in patients on EAP velaglucerase alfa who completed 6, 9, or 12 months as intravenous every-other-week ERT.MethodEAP was approved by the Israeli Ministry of Health. All patients enrolled in the EAP were included for safety measures; only those with > 6 month evaluations of hemoglobin, platelet counts, and liver and spleen volumes were included for efficacy. Descriptive statistics were employed.ResultsAmong 71 EAP patients, there were no drug-related serious adverse events or withdrawals; one patient (1.4%) with previous hypersensitivity to a different ERT had a drug-related allergic reaction. Of 44 patients with appropriate time-period evaluations, 8 patients were treatment-naïve and responded well to velaglucerase alfa. The 36 switch-over patients remained at imiglucerase low-doses; a majority of patients showed improvements in each efficacy parameter.ConclusionSwitch-over from imiglucerase (10–224 months) was safe and in several patients velaglucerase alfa induced a booster-effect.