Sanofi's Genzyme unit has been boosted by the news that the US Food and Drug Administration has approved its manufacturing plant for the production of its Fabry disease drug of Fabrazyme, days after European regulators gave the plant the thumbs-up.

Approval of the Framingham, Massachusetts site allows Genzyme "to begin the process of returning patients to full dosing (1 mg/kg) levels" of Fabrazyme (agalsidase beta), Sanofi noted. The company added that globally, the complete return to normal supply levels of Fabrazyme will begin in the second quarter as Genzyme "works to obtain all global regulatory approvals throughout the year and to build inventory".

Supplies of the drug have been severely affected since the temporary closure of Genzyme's Allston Landing, Boston facility in June 2009. However, with its manufacturing woes coming to an end, this could be a problem for rival Shire.

The latter has benefited from the Fabrazyme supply problem and third-quarter sales of its Fabry disease drug Replagal (agalsidase alfa) rocketed 40% to $129.0 million.