Santarus, Inc. (NASDAQ: SNTS) and Pharming Group NV (NYSE Euronext: PHARM) today announced that their pivotal Phase III clinical study to evaluate the safety and efficacy of the investigational drug RUCONEST® (recombinant human C1 esterase inhibitor) 50 U/kg for the treatment of acute attacks of angioedema in patients with Hereditary Angioedema (HAE) met the primary endpoint of time to beginning of symptom relief.
A statistically significant difference in the time to beginning of symptom relief was observed in the intent-to-treat populations responses to a Treatment Effect Questionnaire for the primary attack location.
RUCONEST was generally well tolerated in this Phase III clinical study and the frequency of patients experiencing at least one treatment emergent adverse event in the RUCONEST treated group was less than in the placebo group. Within 72 hours of the completion of infusion of study medication, four RUCONEST patients (7%) experienced six adverse events: sneezing, procedural headache, back pain, skin burning sensation, an increase in fibrin D-dimer and lipoma. Within the 72 hour period four placebo patients (22%) experienced four adverse events: sinus congestion, vasomotor rhinitis, diarrhea and dyspepsia. Thromboembolic events, anaphylaxis, or neutralizing antibodies to C1 inhibitor were not observed in any patient. There was one patient in the RUCONEST group that experienced a serious adverse event (abdominal hernia at Day 79) that was assessed by the investigator as not related to the study drug.
"These positive results are consistent with the efficacy data previously reported from two smaller randomized, controlled clinical studies with RUCONEST in patients with HAE, and we believe the results provide strong support for our proposed dosing regimen of 50 U/kg in treating acute attacks of HAE," said Wendell Wierenga, Ph.D., executive vice president of research and development of Santarus.
"We are very pleased with these pivotal study results and look forward to working with our colleagues at Santarus to prepare and submit the Biologics License Application (BLA) for RUCONEST to the FDA in the first half of 2013," said Bruno Giannetti, M.D., Ph.D., chief operations officer of Pharming. "We anticipate that additional data from this Phase III study will be presented at an appropriate medical meeting in 2013."
Santarus licensed exclusive rights to commercialize RUCONEST in North America for the treatment of acute attacks of HAE as well as other potential future indications from Pharming. Under the terms of the license agreement, a $10 million milestone is now payable to Pharming as a result of the successful achievement of the primary endpoint of the Phase III clinical study. An additional $5 million milestone will be payable to Pharming upon U.S. Food and Drug Administration (FDA) acceptance of the BLA for review.
RUCONEST Phase III Clinical Study (Study 1310)
Pharming conducted Study 1310 with RUCONEST under a Special Protocol Assessment (SPA) agreement with the FDA, and the study is intended to support the submission of a BLA in the U.S.
In Study 1310, RUCONEST was evaluated for the treatment of acute attacks of angioedema in patients with HAE in an international, multicenter, randomized, placebo-controlled Phase III study comparing a single IV infusion of 50 U/kg of RUCONEST to a saline control with a primary endpoint of time to beginning of symptom relief.
The time to beginning of symptom relief was defined as the time lapsed from the beginning of the infusion of study medication to the beginning of a persistent beneficial effect based on the patient's responses to a Treatment Effect Questionnaire for the primary attack location.
A 90 day follow-up period was required for each patient enrolled, or until such time that the patient required open-label treatment for a subsequent attack during the 90 day period. The data from the open-label extension are being collected for additional efficacy and safety analyses.
The study enrolled a total of 75 patients who were randomized 3:2 to receive either RUCONEST or saline.