Stem cell clinics make big claims but offer little evidence they can treat osteoarthritic knees

osteoarthritis knee

If someone says they have a success rate of close to 100 percent in treating a major health problem but offer little evidence to back that up, you might be excused for being more than a tad skeptical. And a new study says you would be right.

The health problem in question is osteoarthritis (OA) of the knee, something that affects almost 10 million Americans. It’s caused by the wearing down of the protective cartilage in the knee. That cartilage acts as a kind of shock absorber, so when it’s gone you have bone rubbing against bone. That’s not just painful but also debilitating, making it hard to lead an active life.

There is a lot of research taking place – including a clinical trial that CIRM is funding – that focuses on using stem cells to create new cartilage, but so far nothing has been approved by the US Food and Drug Administration for wider use. The reason for that is simple. No approach has yet proven it is both safe and effective.

No evidence? No worries

But that doesn’t stop many clinics around the US, and around the world, from claiming they have treatments that work and charging patients a hefty sum to get them.

In a study presented at the Annual Meeting of the American Academy of Orthopaedic Surgeons, researchers contacted 317 clinics in the US that directly market stem cell therapies to consumers. They asked the clinics for information on the cost of the procedure and their success rate.

  • Only 65 clinics responded
  • Lowest price was $1,150
  • Highest price was $12,000,
  • Average price of $5,156.

Only 36 clinics responded with information about success rates.

  • 10 claimed between 90 and 100 percent success
  • 15 claimed 80 to 90 percent success
  • 10 claimed 70 to 80 percent
  • One said just 55 percent.

None offered any evidence based on a clinical trial that supported those claims, and there was no connection between how much they charged and how successful they claimed to be.

In a news release about the study – which appears in the Journal of Knee Surgery – George Muschler, one of the lead authors, said that orthopedic surgeons have a duty to give patients the best information available about all treatment options.

“Recent systematic reviews of cellular therapies for the treatment of knee OA (over 400 papers screened) have found poor levels of evidence for the efficacy of these treatments to date. Current evidence does not justify the rapid rate of growth for these therapies.”

Nicolas Piuzzi, the other lead author on the study, says if the evidence doesn’t justify the growth in the number of clinics offering these therapies, it certainly doesn’t justify the prices they charge.

“The claim of “stem cell” therapy carries a high level of expectations for the potential benefits, but research is still many years away from providing clear evidence of effective treatment to patients. As clinicians and researchers, we have ethical, scientific, legal and regulatory concerns. Patients need to be aware of the status of research within the field. If they receive information from anyone offering a treatment claim of an 80 to 100 percent successful recovery, they should be concerned in observance of published peer-reviewed evidence.”

Clever technique uncovers role of stem cells in cartilage repair

Over 50 million adults in the U.S. are estimated to be affected by some form of arthritis, a very painful, debilitating condition in which the cartilage that provides cushioning within bone joints gradually degrades. Health care costs of treating arthritis in California alone has been estimated at over $12 billion and that figure is already over a decade old. Unfortunately, the body doesn’t do a good job at healing cartilage in the joint so doctors rely mostly on masking symptoms with pain management therapy and, in severe cases, resorting to surgery.

Illustration of damaged cartilage within an osteoarthritic hip joint Image: Wikipedia/Open Stax

Mesenchymal stem cells (MSCs) – found in bone marrow, fat and blood – give rise to several cell types including cartilage-producing cells called chondrocytes. For that reason, they hold a lot of promise to restore healthy joints for arthritis sufferers. While there is growing evidence that injection of MSCs into joint cartilage is effective, it is still not clear how exactly the stem cells work. Do they take up residence in the cartilage, and give rise to new cartilage production in the joint? Or do they simply release proteins and molecules that stimulate other cells within the joint to restore cartilage? These are important questions to ask when it comes to understanding what tweaks you can make to your cell therapy to optimize its safety and effectiveness. Using some clever genetic engineering techniques in animal models, a research team at the University of Veterinary Medicine in Vienna, Austria report this week in JCI Insights that they’ve uncovered an answer.

Tracking the fate of a stem cell treatment after they’ve been injected into an animal, requires the attachment of some sort of “beacon” to the cells. A number of methods exist to accomplish this feat and they all rely on creating transgenic animals engineered to carry a gene that produces a protein label on the cells. For instance, cells from mice or rats engineered to carry the luciferase gene from fireflies, will glow and can be tracked in live animals. So, in this scenario, MSCs from a genetically-engineered donor animal are injected into the joints of a recipient animal which lacks this protein marker. This technique allows the researchers to observe what happens to the labeled cells.

There’s a catch, though. The protein marker carried along with the injected cells is seen as foreign to the immune system of the animal that receives the cells. As a result, the cells will be rejected and destroyed. To get around that problem, the current practice is to use recipient animals bred to have a limited immune response so that the injected cells survive. But solving this problem adds yet another: the immune system plays a key role in the mechanisms of arthritis so removing the effects of it in this experiment will likely lead to misinterpretations of the results.

So, the research team did something clever. They genetically engineered both the donor and recipient mice to carry the same protein marker but with an ever-so-slight difference in their genetic code. The genetic difference in the protein marker was large enough to allow the team to track the donor stem cells in the recipient animals, but similar enough to avoid rejection from the immune system. With all these components of the experiment in place, the researchers were able to show that the MSCs release protein factors to help the body repair its own cartilage damage and not by directly replacing the cartilage-producing cells.

Stem cell agency funds clinical trials in three life-threatening conditions

strategy-wide

A year ago the CIRM Board unanimously approved a new Strategic Plan for the stem cell agency. In the plan are some rather ambitious goals, including funding ten new clinical trials in 2016. For much of the last year that has looked very ambitious indeed. But today the Board took a big step towards reaching that goal, approving three clinical trials focused on some deadly or life-threatening conditions.

The first is Forty Seven Inc.’s work targeting colorectal cancer, using a monoclonal antibody that can strip away the cancer cells ability to evade  the immune system. The immune system can then attack the cancer. But just in case that’s not enough they’re going to hit the tumor from another side with an anti-cancer drug called cetuximab. It’s hoped this one-two punch combination will get rid of the cancer.

Finding something to help the estimated 49,000 people who die of colorectal cancer in the U.S. every year would be no small achievement. The CIRM Board thought this looked so promising they awarded Forty Seven Inc. $10.2 million to carry out a clinical trial to test if this approach is safe. We funded a similar approach by researchers at Stanford targeting solid tumors in the lung and that is showing encouraging results.

Our Board also awarded $7.35 million to a team at Cedars-Sinai in Los Angeles that is using stem cells to treat pulmonary hypertension, a form of high blood pressure in the lungs. This can have a devastating, life-changing impact on a person leaving them constantly short of breath, dizzy and feeling exhausted. Ultimately it can lead to heart failure.

The team at Cedars-Sinai will use cells called cardiospheres, derived from heart stem cells, to reduce inflammation in the arteries and reduce blood pressure. CIRM is funding another project by this team using a similar  approach to treat people who have suffered a heart attack. This work showed such promise in its Phase 1 trial it’s now in a larger Phase 2 clinical trial.

The largest award, worth $20 million, went to target one of the rarest diseases. A team from UCLA, led by Don Kohn, is focusing on Adenosine Deaminase Severe Combined Immune Deficiency (ADA-SCID), which is a rare form of a rare disease. Children born with this have no functioning immune system. It is often fatal in the first few years of life.

The UCLA team will take the patient’s own blood stem cells, genetically modify them to fix the mutation that is causing the problem, then return them to the patient to create a new healthy blood and immune system. The team have successfully used this approach in curing 23 SCID children in the last few years – we blogged about it here – and now they have FDA approval to move this modified approach into a Phase 2 clinical trial.

So why is CIRM putting money into projects that it has either already funded in earlier clinical trials or that have already shown to be effective? There are a number of reasons. First, our mission is to accelerate stem cell treatments to patients with unmet medical needs. Each of the diseases funded today represent an unmet medical need. Secondly, if something appears to be working for one problem why not try it on another similar one – provided the scientific rationale and evidence shows it is appropriate of course.

As Randy Mills, our President and CEO, said in a news release:

“Our Board’s support for these programs highlights how every member of the CIRM team shares that commitment to moving the most promising research out of the lab and into patients as quickly as we can. These are very different projects, but they all share the same goal, accelerating treatments to patients with unmet medical needs.”

We are trying to create a pipeline of projects that are all moving towards the same goal, clinical trials in people. Pipelines can be horizontal as well as vertical. So we don’t really care if the pipeline moves projects up or sideways as long as they succeed in moving treatments to patients. And I’m guessing that patients who get treatments that change their lives don’t particularly