The FDA's Circulatory System Devices Panel sent a mixed message to the FDA today about CardioMEMS Champion HF Pressure Measurement System. The small implantable device provides provides daily pulmonary artery pressure measurements to guide physicians in their treatment of patients with congestive heart failure.
In December 2011 the same panel voted 9-1 that the device was safe, 7-3 that the device had not been shown to be effective, and 6-4 that the benefits did not outweigh the risks. Now, two years, later, the vote wasn't much different: the panel agreed unanimously (11-0) that the device was safe; 7-4 that it had not been shown to be effective, and 6-4-1 that the benefits outweighed the risks.
Panel member Rick Lange said that the panel today tried to look beyond the pivotal Champion clinical trial, which was the subject of considerable controversy at the earlier meeting. Instead, the panel today wrestled with the followup study, but found it difficult to draw conclusions based on unrandomized and unblinded followup data of a segment of the original trial population. The problem, according to Lange, is that although the patients seemed to have less heart failure, it was impossible for the panel members to tie the daily measurements of the pulmonary artery to a decrease in hospitalizations or other important clinical outcomes. "We couldn't connect the dots," said Lange.
Another major dilemma faced by the panel was the complete lack of evidence showing efficacy in women. "You can't assume in today's world that what's effective in males is effective in females," said Lange.
CardioMEMS is partly owned by St. Jude Medical, which has an option to purchase the rest of the company.
