Bayer's Investigational Riociguat Meets Primary Endpoint in Phase III Study in Patients with Pulmonary Arterial Hypertension (PAH)

Bayer's Investigational Riociguat Meets Primary Endpoint in Phase III Study in Patients with Pulmonary Arterial Hypertension (PAH)

WAYNE, N.J., Oct. 22, 2012 -- /PRNewswire/ -- Bayer HealthCare today announced data from the Phase III PATENT-1 pulmonary arterial hypertension (PAH) trial evaluating its investigational drug riociguat in both treatment-naive patients and those pre-treated with an endothelin receptor antagonist or an oral, inhaled or subcutaneous prostanoid. The study met its primary endpoint by demonstrating a statistically significant improvement in the six-minute walk distance (6MWD) with patients treated with riociguat showing an improvement of 36 meters 95%-CI [20-52 meters] (p<0.0001) after 12 weeks compared with placebo.[1]  The results will be presented as a late-breaking abstract in an oral abstract session at CHEST 2012, the annual meeting of the American College of Chest Physicians (ACCP) in Atlanta, Georgia (Abstract No. 1462799).

In addition to meeting its primary endpoint, trial results also showed a statistically significant improvement in 6MWD both in the treatment-naive patient group (38 meters after 12 weeks compared with placebo [95%-CI 15-62 meters]) and the pre-treated patient group (36 meters after 12 weeks compared with placebo [95%-CI 15-56 meters]).[1]

Pulmonary arterial hypertension (PAH), one of the five types of PH, is a rare and lifethreatening disease characterized by elevated pressure in the pulmonary arteries.

"The six-minute walk distance test is a well-validated clinical measure in patients with PAH, and therefore, the results of the PATENT-1 trial are encouraging," said Professor Hossein Ardeschir Ghofrani of University Hospital Giessen and Marburg, Germany and principal investigator of the PATENT study.  "These data from the PATENT study suggest that riociguat may be a potential treatment option both for patients who have never been treated for PAH as well as for those who have received prior treatment."

The ten most frequently reported treatment emergent adverse events with riociguat vs. placebo were: headache (27% vs. 20%), dyspepsia (19% vs. 8%), peripheral edema (17% vs. 11%), nausea (16% vs. 13%), dizziness (16% vs. 12%), diarrhea (14% vs. 10%), nasopharyngitis (10% vs. 11%), dyspnea (6% vs. 11%), cough (5% vs. 10%) and vomiting (10% vs. 9%).[1]

Statistically significant improvements were also observed across secondary endpoints including pulmonary vascular resistance (PVR) (p<0.0001), N-terminal prohormone brain natriuretic peptide (NT-pro BNP) (p<0.0001), WHO functional class (FC) (p=0.0033), time to clinical worsening (TTCW) (p=0.0046) and Borg dyspnea score (p=0.0022). Secondary endpoints that did not achieve statistical significance include the European quality of life 5-dimensions questionnaire (EQ-5D) (p=0.0660) and living with pulmonary hypertension questionnaire (LPH) (p=0.0019).[1]

"New treatment options are needed for people living with PAH," Pamela Cyrus, MD, Vice President and Head, U.S. Medical Affairs, Bayer HealthCare Pharmaceuticals. "Bayer HealthCare is committed to addressing the unmet needs of pulmonary hypertension patients by developing innovative medicines."

About PATENT PATENT (Pulmonary Arterial Hypertension sGC-Stimulator Trial) is an ongoing Phase III trial to assess oral riociguat in the treatment of treatment naive patient and pre-treated patients with symptomatic PAH.  PATENT is a multi-center, multi-national program with active centers in 32 countries. The program includes a randomized, double-blind, placebo-controlled trial phase (PATENT-1) and an open label extension trial phase (PATENT-2). In the PATENT-1 study, 445 patients with symptomatic PAH were randomized to receive either placebo or two different doses of riociguat orally over a period of 12 weeks.  The riociguat dose is titrated, over a period of eight weeks in doses of 0.5 mg increments from 1.0 mg up to 2.5 mg three times daily. Patients are then followed for an additional four weeks to complete the study. Patients then have the option of participating in the open label extension study, after completing an eight-week blinded sham titration.

About Riociguat Riociguat (BAY 63-2521), discovered and developed at the Bayer research laboratories, is an investigational oral soluble guanylate cyclase (sGC) stimulator.  In addition to PAH, riociguat is currently under investigation for other types of pulmonary hypertension, including chronic thromboembolic pulmonary hypertension (CTEPH). The CHEST study is a Phase III trial assessing oral riociguat in patients with CTEPH.  Data from the first phase of the study, CHEST-1, will be presented at the "Late Breaking Abstracts" session at the CHEST congress (Abstract No. 1462924).

Riociguat is an investigational agent and is not approved by the FDA, EMA or other health authorities.  

About Bayer HealthCare Pharmaceuticals Inc. Bayer HealthCare Pharmaceuticals Inc. is the U.S.-based pharmaceuticals business of Bayer HealthCare LLC, a subsidiary of Bayer AG. Bayer HealthCare is one of the world's leading, innovative companies in the healthcare and medical products industry, and combines the activities of the Animal Health, Consumer Care, Medical Care, and Pharmaceuticals divisions.  As a specialty pharmaceutical company, Bayer HealthCare provides products for General Medicine, Hematology, Neurology, Oncology and Women's Healthcare.  The company's aim is to discover and manufacture products that will improve human health worldwide by diagnosing, preventing and treating diseases.

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Forward-Looking Statements This release may contain forward-looking statements based on current assumptions and forecasts made by Bayer Group or subgroup management. Various known and unknown risks, uncertainties and other factors could lead to material differences between the actual future results, financial situation, development or performance of the company and the estimates given here. These factors include those discussed in Bayer's public reports which are available on the Bayer website at www.bayer.com. The company assumes no liability whatsoever to update these forward-looking statements or to conform them to future events or developments.

[1] Ghofrani, HA. et al. Riociguat for the treatment of pulmonary arterial hypertension: a randomized, double-blind, placebo-controlled study (PATENT-1). CHEST 2012, Atlanta, USA. Oral presentation. Abstract 1462799.

SOURCE Bayer HealthCare