Specialty biopharmaceutical company Santarus, Inc. and biotech company Pharming Group NV announced the submission of a Biologics License Application (BLA) to the US Food and Drug Administration (FDA) to obtain marketing approval for RHUCIN (recombinant human C1 inhibitor) for the treatment of acute angioedema attacks in patients with Hereditary Angioedema (HAE).

The safety and efficacy of RHUCIN for the treatment of HAE attacks were evaluated in two randomized placebo-controlled studies and are supported by four open label treatment studies. Both placebo-controlled clinical studies showed statistically significant and clinically relevant improvement in the primary endpoint of time to beginning of relief of symptoms at RHUCIN dosage strengths of 50 U/kg and 100 U/kg compared to placebo.

In October 2010, Pharming received Marketing Authorization for RUCONEST (RHUCIN in non-European countries) for the treatment of acute HAE in the European Union. Pharming has updated the clinical dataset reviewed and approved by the European Medicines Agency with additional patient data and analyses. In total, the BLA dossier includes nine clinical studies covering 714 administrations in 190 subjects.

Santarus has licensed certain exclusive rights from Pharming to commercialize RHUCIN in North America for the treatment of acute attacks of HAE and other future indications. Under the terms of the license agreement, a $5 million milestone is payable to Pharming upon FDA acceptance for review of the BLA for RHUCIN.

RHUCIN (INN conestat alfa) is a recombinant version of the human protein C1 inhibitor (C1INH). RHUCIN is produced through Pharming's proprietary technology in milk of transgenic rabbits and in Europe is approved under the name RUCONEST for treatment of acute angioedema attacks in patients with HAE. The FDA has granted Orphan Drug and Fast Track Status to RHUCIN for the treatment of acute attacks of HAE, a genetic disorder in which the patient is deficient in or lacks a functional plasma protein C1 inhibitor, resulting in unpredictable and debilitating episodes of intense swelling of the extremities, face, trunk, genitals, abdomen and upper airway.

The frequency and severity of HAE attacks vary and are most serious when they involve laryngeal edema, which can close the upper airway and cause death by asphyxiation. According to the US Hereditary Angioedema Association, epidemiological estimates for HAE range from one in 10,000 to one in 50,000 individuals.

Based on prior discussions with the FDA, Pharming is planning to initiate an additional randomized placebo-controlled, clinical study with RHUCIN in approximately 50 patients to provide additional data in support of the 50 U/kg dose. Data from the placebo-controlled study will also be used to provide additional validation of the visual analogue scale used in measuring the clinical effects of RHUCIN.

Pharming Group NV is developing innovative products for the treatment of unmet medical needs. RUCONEST (RHUCIN in non-European territories) is a recombinant human C1 inhibitor approved for the treatment of angioedema attacks in patients with HAE in all 27 EU countries plus Norway, Iceland and Liechtenstein. The product is also under development for follow-on indications, i.e. Antibody-Mediated Rejection (AMR) and Delayed Graft Function (DGF) following kidney transplantation. Pharming's advanced technologies include innovative platforms for the production of protein therapeutics, technology and processes for the purification and formulation of these products.

Santarus, Inc. is a specialty biopharmaceutical company focused on acquiring, developing and commercializing proprietary products that address the needs of patients treated by physician specialists. The company's current commercial efforts are focused on Glumetza (metformin hydrochloride extended release tablets) and Cycloset (bromocriptine mesylate) tablets, which are indicated as adjuncts to diet and exercise to improve glycemic control in adults with type 2 diabetes. Cycloset was commercially launched in November 2010.

Santarus also has a diverse development pipeline with three late-stage product candidates in phase III clinical programs: Ultesa (budesonide MMX) for induction of remission of active ulcerative colitis, rifamycin SV MMX for treatment of travellers’ diarrhoea and RHUCIN (recombinant human C1 inhibitor) for treatment of acute attacks of hereditary angioedema. In addition, Santarus plans to initiate a phase I clinical study in the first half of 2011 with SAN-300, its anti-VLA-1 antibody, which the company expects to investigate for the treatment of rheumatoid arthritis.