Tissue bank employs gamma irradiation

01/01/2004

by MARK.A DeSORBO

KENNESAW, Ga.—Hoping to prevent the same compliance and contamination issues that have plagued the company for more than two years, CryoLife Inc., the nation's largest supplier of living human tissue, has employed a patented technology that will minimize pathogens in donor tissue.

Joseph Schepers, CryoLife's vice president of corporate communications, says the technology developed by the Los Angeles, Calif.-based Clearant, Inc. uses gamma irradiation and is designed to substantially reduce microbial contamination while maintaining tissue integrity.

"This is a joint effort," says Schepers. "CryoLife and Clearant scientists will be working together. We will be doing the validation of our process in-house with the support of Cleanrant, but the actual sterilization will be done off site."

In addition to adding gamma irradiation, CryoLife will also use a "radio-protectant"—a solution that maintains the tissue throughout radiation process—through which all donated tissue is processed. The tissue then undergoes a "rinse procedure" to identify microorganisms and bacteria that may not have been killed initially. "We will be analyzing the solution that tissues are packaged in," says Schepers. "Then we do a rinse recovery, which is a very sensitive yet accurate test for microorganisms."

CryoLife's announcement in mid-December came just 10 days after a Colorado teenager who underwent knee surgery in September became severely ill because the living tissue that was processed by CryoLife for use in the operation was contaminated.

During surgery, the 17-year-old boy, who has since been released from a second hospital stay, received tissue that came from CryoLife. The company processes several types of human tissues—tendons and cartilage—used in orthopedic procedures. In its ISO Class 7 cleanrooms, CryoLife also manufactures vascular products such as heart valves, and "BioGlue," which helps doctors to control bleeding during surgery.

According to Ellen Lee, a spokesperson from the U.S. Centers for Disease Control and Prevention (CDC), the tissue was infected with Group A streptococcus. Five other patients who underwent surgical procedures, she adds, were given the same donor tissue that was used in the Colorado boy's surgery with no apparent complications.

The incident comes two years after the death of 23-year-old Brian Lykins of Wilmar, Minn., following routine knee surgery. Lykins' death triggered a slew of lawsuits and a CDC investigation that linked CryoLife to 13 other cases of post-transplanted tissue infections.

The Food and Drug Administration continues to monitor the company, and Schepers points out that CryoLife is working closely with the agency and making improvements to processes.

In August 2002, the FDA ordered a recall of certain CryoLife products and temporarily suspended certain company operations. The FDA alleged that CryoLife had not validated procedures for preventing infectious disease contamination or cross-contamination of tissue during processing, at least since October 2001.

Following the FDA order, numerous lawsuits were filed against CryoLife. The company also faces a consolidated suit that seeks class-action status, alleging that CryoLife failed to disclose its alleged lack of compliance with certain FDA regulations regarding the handling and processing of certain tissues and other product safety matters.

"We have had over 100,00 patients who have received CryoLife tissues, and we have a very low infection rate—less than one percent—but we are continuing to make improvements and we have settled most of the lawsuits," says Schepers. Last August, CryoLife hired Thomas Lynch, a former FDA official, to head the company's newly created department of regulatory affairs and quality assurance. The company also created an in-house pathology department.

"Our ultimate goal is to provide patients with sterile orthopaedic tissue," said CryoLife president and CEO Steven G. Anderson in a prepared statement.