OSAKA - A woman in her 50s with severe heart failure underwent what was described as the world's first surgery using commercially available iPS cell-derived heart muscle sheets at an Osaka hospital on September 29, marking the first practical use of the regenerative treatment.
During the procedure, doctors attached three thin sheets made from induced pluripotent stem, or iPS, cells to the surface of the patient's heart. The sheets contain heart muscle cells created from iPS cells and are designed to promote regeneration of cardiac muscle and help restore the heart's pumping function.
The patient was diagnosed with severe heart failure about four years ago. Her heart's pumping ability had deteriorated to a level where conventional treatment was not expected to restore its function.
Until now, patients in such circumstances have generally faced limited options, including continuing medication or receiving a heart transplant. Heart transplantation is constrained by a shortage of donors in Japan, with some patients waiting more than five years.
The heart muscle sheets are expected to provide another treatment option for patients whose conditions previously could not be effectively treated.
The operation had been scheduled to take about two hours but proceeded smoothly and was completed in 52 minutes.
The technology gained wider public attention during the Osaka-Kansai Expo, where the heart muscle sheets were displayed. The patient initially had concerns about undergoing the new treatment but said seeing the technology presented publicly at the Expo helped reassure her.
Professor Emeritus Yoshiki Sawa, who performed the surgery and has played a leading role in developing the treatment, said its presentation at the Expo may also have helped generate greater government support for the technology.
The heart muscle sheets are covered by Japan's public health insurance system. Their official drug price is 53.2 million yen, but the country's high-cost medical expense system substantially reduces the amount patients are required to pay.
Depending on a patient's annual income, the out-of-pocket cost is expected to range from about 530,000 yen to 1.68 million yen a year.
Sawa said Japan now has an opportunity to industrialize and expand regenerative medicine using iPS cells.
The heart muscle sheets are currently produced largely by hand, limiting production capacity to enough material for about 30 to 40 patients a year. A system capable of mass cultivation is now being prepared in an effort to increase supply.
The September 29 operation involved treatment for heart failure, while applications of iPS cell technology for conditions including Alzheimer's disease, cervical cancer and Parkinson's disease have also already received formal approval.
Sawa said the challenge is to bring regenerative treatments into practical use as quickly as possible so they can benefit more people suffering from difficult-to-treat diseases. He also noted that clinical trials require substantial funding and argued that development should be advanced as a national project.
Nearly 20 years after iPS cells were first discovered, their use in this form of heart surgery represents a major step toward clinical application, but researchers say the technology is still at an early stage and that expanding practical use will be the next major challenge.
Source: YOMIURI
