ViroPharma Inc. ( VPHM - Snapshot Report ) presented promising data on Cinryze at the American College of Allergy, Asthma and Immunology’s (ACAAI) annual congress. Data was presented from a post marketing study that evaluated the safety, tolerability and efficacy of Cinryze in escalating doses in patients with hereditary angioedema (HAE), who did not show sufficient treatment benefit with 1000 units every 3 or 4 days.

The open-label multicenter study enrolled 20 patients over a span of 3 years. It was observed that doses up to 2500 units every 3 or 4 days can be prescribed to patients who show insufficient response to bi-weekly 1000 units. Additionally, Cinryze was found to be well tolerated and side effects observed were consistent with previous studies.

We note that Cinryze is approved both in the US and Europe. In the US, the drug is approved for routine prophylaxis against angioedema attacks in adolescent and adult patients with HAE. In Europe, it is approved for routine prevention, pre-procedure prevention and acute treatment of angioedema attacks in adolescent and adult patients with HAE.

The company is also evaluating the subcutaneous administration of Cinryze in combination with its partner, Halozyme Therapeutics’ ( HALO - Snapshot Report ) recombinant human hyaluronidase enzyme (rHuPH20). In September 2012, the US Food and Drug Administration (FDA) removed a clinical hold on the phase II study. The company plans to initiate a phase II study in the EU shortly.

In the third quarter of 2012, Cinryze’s net sales climbed 30.4% y/y to $85.3 million, driven by higher demand. Bulk of the sales ($84 million) came from the US. US sales were reflective of patient demand ($82 million) and inventory build up ($2 billion), according to management.

Recommendation

We currently have a Neutral recommendation on ViroPharma. The stock carries a Zacks #3 Rank (Hold rating) in the short run.

We are encouraged by Cinryze’s sales growth and patient additions in the third quarter of 2012. However, we remain concerned about the lack of late-stage pipeline candidates and the company’s dependency on Cinryze for growth.