Shire's investigational treatment for Gaucher disease could be on the market very soon after the start of a rolling submission to US regulators on the basis of a promising late-stage trial.

The company has reported positive results from the first of three Phase III studies of velaglucerase alfa, for the treatment of type 1 Gaucher disease. On the back of that data, the US Food and Drug Administration has accepted its treatment protocol for the enzyme replacement therapy and Shire has begun its rolling submission of a New Drug Application under the fast-track process begun to cope with a potential shortage of the approved drug for Gaucher, Genzyme Corp's Cerezyme (imiglucerase).

The study looked at 25 patients who showed clinical manifestations of Gaucher disease –thrombocytopenia, moderate splenomegaly “or a readily palpable enlarged liver”, Shire noted. Those receiving velaglucerase at 45 U/kg for a year saw statistically significant improvements in haemoglobin, platelet count and spleen volume, while a trend in liver volume reduction was observed.

Sylvie Gregoire, president of Shire Human Genetic Therapies, said the company was pleased with the progress of the velaglucerase programme, which involves over 100 patients in 10 countries, “from both a clinical and regulatory perspective”. She added that the data are consistent with those from Phase I/II and extension studies and “we will continue to work diligently with the FDA and other regulatory agencies to make velaglucerase alfa available as soon as possible”.

Now that the protocol has been approved by the FDA, doctors can treat Gaucher patients with velaglucerase before it becomes commercially available and Shire will provide the treatment free of charge initially, in order to provide access to patients as quickly as possible. The situation has arisen as a result of Genzyme temporarily shutting down its manufacturing facility in Boston in June after a bioreactor was contaminated with a virus. This affected production of Cerezyme and Fabrazyme (agalsidase beta), which is indicated for Fabry disease.

Analysts believe that doctors will now get used to prescribing velaglucerase so that if full approval is granted, the therapy could make major inroads into Genzyme’s lucrative market. Worldwide, the diagnosed population of Gaucher patients is just 7,000 and yet Cerezyme sales reached $1.2 billion in 2008.