Pharmaceutical Business review

Myogen shares nosedive on hypertension trial delay

In January 2004, Myogen announced the initiation of patient enrollment in ARIES 1 and 2, two 186-patient trials in pulmonary arterial hypertension (PAH). ARIES-1 is currently being conducted in North America and Australia, while ARIES-2 is being conducted in Western and Eastern Europe, Israel and South America.

The company’s initial goal was to complete patient enrollment in both trials by the end of the first half of 2005. However, based on recent enrollment in ARIES-1, the company now expects enrollment in ARIES-2 will be completed in the fourth quarter of 2005.

ARIES-2 continues to progress in line with prior guidance and is expected to complete enrollment by the end of June 2005.

Myogen expects to report preliminary results of each trial approximately six months after completion of patient enrollment.

Enrollment in ARIES-1 has been affected by a number of factors, including a decline in the availability of treatment-naive PAH patients due to increasing market penetration of bosentan, as well as the expanded use of sildenafil following the release of clinical data in October 2004. Additionally, other clinical trials are competing for this group of patients.