FDA approves high titre manufacture of Tysabri

19-Apr-2009 - Last updated on 20-Apr-2009 at 10:30 GMT

The FDA has approved Biogen Idec to manufacture Tysabri using a high titre process but the product’s sales have been “negatively impacted” by the cases of patients developing PML.

Tysabri (natalizumab) was pulled from the market for 18 months in 2005 because of a suspected link to progressive multifocal leukoencephalopathy (PML), a rare brain infection. The product was reintroduced in July 2006 and since then there have been six reported cases of PML.

This is within the ratio detailed on the drugs label but Biogen still believes the PML concern is hindering growth. Despite this sales of Tysabri rose 44 per cent in its latest results and the US Food and Drug Administration’s (FDA) approval of the high titre process is a further boost for the product.

Bob Hamm, chief operating officer of Biogen, said: “Developing this high titer process is another example of our world-class expertise and leadership in biologics manufacturing. We expect this new process to result in about a four-fold increase in yield.”

Biogen also received approval of the high titre process from the European Medicines Agency (EMEA) in December.

Recession hinders growth

Biogen’s profits for the quarter rose by almost 50 per cent to $244m (€188m) underpinned by the sharp rise in Tysabri sales. However, Tysabri’s sales growth fell short of analysts’ predictions and Biogen has suggested that this may be due to the recession.

Paul Clancy, Biogen’s chief financial, commented that rising unemployment in the US has been mirrored by an increasing number of patients receiving free drugs, which he estimated had cost the company’s top line $6m to $10m.