Stem cell products developer Aastrom Biosciences (Ann Arbor, Michigan) said Monday that a patient enrolled in the company's U.S. Phase II heart failure trial developed a serious adverse event associated with anesthesia management during treatment at one of the study sites.
Aastrom suspended trial enrollment at the site where the event took place while it conducted an internal review. The internal review and another review by an independent data safety monitoring board determined that the anesthesia-related adverse event was an isolated incident and unrelated to the cells.
However, the FDA has since placed all trials sites under a clinical hold while the agency conducts its own review of the incident.
The patient who experienced the adverse event has since recovered and is doing well, Elmar Burchardt, vice president of medical affairs at Aastrom, told Medical Device Daily's sister publication, BioWorld Today. He emphasized that the adverse event had nothing to do with the cardiac repair cells (CRCs) used in the trial or the way in which they were administered. Nor did the adverse reaction occur as a result of the surgical procedure used to inject the cells, he said.
The adverse event occurred due to a lack of patient monitoring, resulting in the patient developing what Burchardt said were "electrolyte problems." That patient wasn't being properly managed during anesthesia and slipped into an electrolyte imbalance, he explained.
Patients in the study are supposed to be tightly monitored to control blood gases and electrolytes, but this did not happen for that one patient. "Anesthesiology standards were not adhered to in this case," Burchardt said.
But he said the company has taken steps to ensure that the problem was not repeated at that site, and has requested a corrective plan to ensure that only senior staff does the anesthesia.
The FDA has authorized Aastrom to proceed with the CRC treatment for one patient previously enrolled in the study of patients with dilated cardiomyopathy. Many of the 5.5 million people in the U.S. suffering from severe heart failure have the condition, where expansion of the patient's heart reduces pump function, making it impossible to maintain normal blood circulation.
In addition, follow-up monitoring of patients who have previously been treated in the trial is continuing in accordance with the study protocol.
The trial in DCM patients is the first clinical trial in the U.S. to evaluate the surgical delivery of autologous cells directly into the human heart muscle for the treatment of congestive heart failure associated with DCM in both ischemic and non-ischemic patients. Patients randomized into the treatment group of the trail are treated with Aastrom's CRCs, an autologous, mixed-cell product containing expanded populations of stem and early progenitor cells produced from a small sample of the patient's own bone marrow.
The clinical hold in the DCM trial has no effect on the company's trial in patients with critical limb ischemia that reached its benchmark of treating 30 patients last October. Those 30 patients will undergo a year of follow up and data could be released by the end of 2009, according to Kimberli O'Meara, investor relations representative at Aastrom.