Lev Pharmaceuticals, Inc announced that the US Food and Drug Administration (FDA) approved Cinryze (C1 inhibitor (human)) for routine prophylaxis against angioedema attacks in adolescent and adult patients with hereditary angioedema (HAE), also known as C1 inhibitor deficiency. Cinryze is expected to be commercially available for prophylaxis against HAE later this year.

Cinryze is the first and only FDA-approved C1 inhibitor therapy for routine prophylaxis against HAE attacks in the US. HAE is characterized by painful, debilitating and sometimes fatal swelling of the extremities, face, genitals, abdomen and laryngeal tract. These attacks, which affect an estimated 10,000 people in the US, are often unpredictable and may be spontaneous or precipitated by emotional or physical stress.

"Until now, living with HAE has been a life-altering, constraining, and truly debilitating experience," said Michael Frank, professor, Paediatric Allergy and Immunology Division, Duke University School of Medicine. "The approval of this therapy - which has been shown to safely decrease HAE attacks in these patients - represents the potential for patients to live a more normal life."

"With this approval, patients with HAE will have access to a therapy that helps reduce the frequency and severity of debilitating and potentially life-threatening HAE attacks, said Joshua Schein, chief executive officer of Lev. "Cinryze can help these patients live healthier, more productive and predictable lives."

A programme will be offered to provide support services such as benefit coverage investigations, prior authorizations and broad-based reimbursement assistance for patients and health care providers. This programme will also assist patients and health care providers by helping to secure adequate insurance coverage for Cinryze C1 inhibitor. The company is committed to assuring access to Cinryze for all patients who may benefit from therapy.

Until now, HAE patients in the US had to rely on anabolic steroids as the only approved products for prevention of HAE. These products carry the risk of significant adverse effects, such as liver toxicity and carcinogenicity. Additionally, such anabolic steroids are not a realistic option for a large segment of the population.

"We are ecstatic that the US HAE community will finally have access to a safe and effective HAE therapy," said Anthony J Castaldo, president of the US Hereditary Angioedema Association. "Today's approval addresses a longstanding, catastrophic unmet medical need with a therapy that save lives and helps patients overcome the devastating burden posed by this debilitating and life-threatening disease."

As part of the approval, a post-approval requirement is to conduct a clinical study designed to evaluate safety, including thrombotic adverse events, efficacy and immunogenicity of higher than labeled doses of Cinryze for routine prophylaxis. Collection and periodic reporting of CMC data also have been requested as a Post-approval commitment.

On July 15, 2008, Lev Pharmaceuticals and ViroPharma Incorporated signed a definitive merger agreement under which ViroPharma will acquire Lev. ViroPharma expects to complete its acquisition of Lev in October 2008. The waiting period required under the Hart-Scott-Rodino Antitrust Improvements Act expired on September 2, 2008; the closing of the transaction is subject to the satisfaction of other customary closing conditions, including the approval of Lev's stockholders.

ViroPharma intends to conduct a conference call to discuss the approval and indication of Cinryze after the close of its acquisition of Lev.

Based on discussions with FDA, Lev has requested the withdrawal of the portion of the application referring to data for the acute treatment of HAE attacks. This data will be resubmitted as a supplemental BLA, along with additional data from ongoing open label acute studies of Cinryze, as soon as possible. The company does not believe that an additional study will be required, but FDA must agree.

Cinryze is a highly purified, pasteurized and nanofiltered plasma-derived C1 inhibitor (human) product that has been approved by FDA for routine prophylaxis against HAE attacks in adults and adolescent patients with HAE. C1 inhibitor therapy has been used for more than 30 years in Europe to treat patients with C1 inhibitor deficiency.

Lev is a biopharmaceutical company focused on developing and commercializing therapeutic products for the treatment of inflammatory diseases.