It's nice to have your drug in high demand. Except, of course, if you can't actually meet demand.

Such is the life of ViroPharma (Nasdaq: VPHM), which saw its stellar launch of hereditary angioedema treatment Cinryze come to a standstill until it could scale up manufacturing further.

Metric

2009 Q3

2009 Q4

2010 Q1

2010 Q2

Cinryze sales (in millions)

$29.1

$36.0

$34.9

$40.3

Sequential sales change from previous quarter

13.7%

23.7%

(3.1%)

15.5%

Source: Company releases.

Increasing production using a process called parallel chromatography helped reaccelerate growth, but the ViroPharma really needs its industrial scale manufacturing to come online to reach the potential $250 million to $350 million in U.S. sales the company has guided for.

Investors are going to have to wait a little longer. ViroPharma announced today that the Food and Drug Administration has turned down, for now, its request to start selling Cinryze manufactured at an industrial scale. The agency wants answers to questions from observations made at the preapproval inspection and has additional questions about the technical processes of making Cinryze at the larger scale.

Issues with scaling up production are nothing new to the industry. Earlier this month, Onyx Pharmaceuticals (Nasdaq: ONXX) announced that it would have to delay its marketing application for its multiple myeloma drug carfilzomib because the FDA wanted additional information about its scaled-up manufacturing process. Amylin Pharmaceuticals (Nasdaq: AMLN) and Eli Lilly (NYSE: LLY) ran into a similar situation with Bydureon, when the FDA decided it needed to run an additional clinical trial to prove that the clinical-trial-scale production was the same as the commercial-scale production. At the extreme, the FDA made Genzyme (Nasdaq: GENZ) give its scaled-up version of Myozyme a different name, Lumizyme, because it was manufactured in a different way.

ViroPharma seems to think the issue is fairly minor. The company is pushing forward with production assuming the FDA will sign off and that it'll be able to sell the product once it does.

If ViroPharma is right, buying on today's dip could be a very well-timed move ahead of a reacceleration of sales.

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