The UK’s Shire says it has enhanced its orphan drug pipeline with the acquisition of Metazym, a treatment for metachromatic leukodystrophy (MLD) from Denmark’s Zymenex.

Metazym (arylsulfatase-A) is an enzyme replacement therapy in Phase I/II clinical trials for MLD, which is described as “a serious, life-limiting disease” in which patients experience progressive irreversible neurological damage. There are approximately 2,000 MLD patients in “developed world markets”, said Shire.

Under the terms of the deal, Shire is paying $135 million for the acquisition of global rights to the product. Zymenex is also providing certain transition services, including know-how transfer, for up to six months after the acquisition is completed. Shire also noted that the transaction includes no royalties or other downstream payment obligations.

Metazym has received US Food and Drug Administration approval for its Investigational New Drug application to initiate a Phase II clinical trial and has been granted orphan drug status in the USA and in the European Union. Sylvie Gregoire, president of Shire's Human Genetic Therapies business, said that the product fits very well with Shire's portfolio of treatments for lysosomal storage disorders.

She added that “by acquiring this mid-stage clinical programme we hope to bring a MLD treatment to patients two years earlier than anticipated”.

Shire gets expanded Vyvanse approval
The deal was sealed hours after Shire’s attention deficit hyperactivity disorder drug Vyvanse (lisdexamfetamine dimesylate) was approved in the USA for use by adult patients.

Vyvanse received the green light from the FDA in February 2007, for children between six and 12. The drug is a follow-up to the firm’s old ADHD treatment Adderall XR (mixed amphetamine salts), which will face generic competition in 2009.