Japan conditionally approves new IPS cell-based heart study

Yoshiki Sawa IPS cells stem cells heart diseease

Where do things stand with IPS cell translational research?

The newest development is that regulators in Japan just have given conditional approval to an Osaka University team to an induced pluripotent stem (IPS) cell-based study for ischemic heart disease.

Screenshot of Yoshiki Sawa slide on IPS cell approach for heart disease
Screenshot of Yoshiki Sawa slide on IPS cell approach for heart failure, which is similar to approach for ischemic heart disease.

For years IPS cell-based products have been on-again off-again in active clinical study for macular degeneration, work led by Dr. Masayo Takahashi. The new heart disease study is led by Yoshiki Sawa. This appears to be the third conditionally approved IPS cell study in Japan. I’m not clear on whether both other studies included in the total of 3 here are from Dr. Takahashi or not.

Here is information on the study design:

“The approved plan will cover patients with ischemic cardiomyopathy, or hearts weakened by narrowed or blocked arteries preventing blood from reaching parts of the heart muscle. Three people aged between 18 and 79 will have two round cell sheets made from the iPS cells of other people attached to the surface of their hearts. The sheets will each be 0.05 millimeters thick and several centimeters in diameter. Researchers will examine the safety of the procedure, checking for cancer, immunorejection and other such signs, and will also observe changes in the function of the patients’ hearts.”

It has a number of key differences with the previous conditionally approved studies beyond the organ of focus. Perhaps the most striking aspect of the new study is that it will use far more cells:

“This is the third case of clinical research involving transplants using iPS cells to be approved. In the previous two cases, groups including the Riken research institute are transplanting several hundred thousand cells in the treatment of intractable diseases. The number of cells in the latest research is far greater — at around 100 million. As there is a risk of iPS cells turning cancerous, it will be crucial for researchers to guarantee the safety of the process.”

Ideally, we don’t want any undifferentiated IPS cells in the transplanted product, but that’s a tall task with 100 million cells. Past studies have suggested that not all IPS cells have tumorigenic potential including in a transplantation context so a few amounts 100 million overall may not cause problems. This will have to be carefully monitored as stressed in the  Mainichi piece. From a second Mainichi article we have a quote on this issue from Dr. Sawa:

“Even if a tumor does develop, because the cells come from another person, it is expected that it will disappear after the suppressants are withdrawn and the person’s natural immune system kicks in.”

I hope he’s right about that.

This is exciting investigational work, but high-risk in my view. It will be interesting to follow.

You can learn more from a slide set from Dr. Sawa’s research here (and see image above from one such slide).

5 Comments


  1. This is GREAT!! I agree that it’s risky. But if we want to pull people away from the stem cell clinics, then scientists need to start taking some chances. Desperate patients will do desperate, stupid things if they don’t have the hope of any other medical options on the horizon.


    • Desperate patients? That sounds to me so very condescending. Many who seek out regenerative therapies do so after becoming pretty well informed first. They do a fair amount of research and weigh their options. I like to consider myself in that caliber of patient. It’s been a very sober and enlightening journey for me. I do not think that Regenerative Clinics, which now number in the U.S. to be in the hundreds, would attract the number of patients they do currently if they were all just a bunch of fly by night operations which is how some have tried to characterize them. To be sure, some regenerative medicine patients have been unfortunately and even permanently injured (blindness) in their quest for better health. However, the entire practice of medicine, generally speaking, is exactly that. A practice! There are different levels of competency as far as health care providers are concerned. In part this is why It is not called the PERFECTION of medicine. There is always the risk of injury in any medical procedure and in any medical profession. Malpractice can happen even to the best of them. This is why you need to do your own independent research first.
      On a personal note, I tore meniscus in both knees and have developed arthritis as a result. I was recommended for surgery as far back as 2012. Since that time, I’ve had about 7 or 8 separate Platelet Rich Plasma injections into both knees. To date I have so far avoided the surgeon’s scalpel as well as general anesthesia which includes it’s own set of potential dangers. I’ll opt for the least invasive and simpler procedure first which I believe is much safer than traditional approaches to my medical circumstances.
      Roger Nocera, MD has written the following……. “a patient’s own healing cells (autologous cells) have an undeniably favorable safety profile”. I believe he is comparing mainstream medicine, like orthopedic surgery, to the practice of regenerative therapies. However the imperfect nature of regenerative medicine, it is likely much safer because of its’ less invasive more biologically compatible approach to healthcare. His book is a little dated, but you could start there by reading “Cells That Heal Us From Cradle To Grave: A Quantum Leap in Medical Science.” I wish you well.


  2. “Even if a tumor does develop, because the cells come from another person, it is expected that it will disappear after the suppressants are withdrawn and the person’s natural immune system kicks in.”

    Doesn’t a person’s immune response to transplanted cells or organs diminish over time?

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