Home › Blog › Why Bad PRP Studies Matter: The Katz PRP JAMA Editorial

Why Bad PRP Studies Matter: The Katz PRP JAMA Editorial

Published on Nov 29, 2021

jama katz prp editorial

We’ve seen a rash of bad PRP studies with negative results lately. Given that we have dozens of positive studies showing that PRP works, the average physician might say, “Why is this a big deal?” After all, we physicians are used to scenarios where most of the research is positive with a handful of negative studies. However, a recent editorial that accompanied the most recent paper in JAMA shows why we all should be very concerned. Let’s dig in.

The Bad Papers

I’ve covered two of the recent papers published in JAMA that had serious issues. One was a negative trial result on the use of PRP in ankle arthritis and the other was a negative result in knee arthritis (1,2). The first paper used a poor PRP system made by Arthrex that isn’t capable of making a product that could be classified as PRP and the second used an even worse kit made by RegenLab that produced a PRP product with a normal whole blood platelet count. Hence, neither study actually tested PRP, despite their titles claiming that they were using PRP. A third paper published in JAMA suffered from the same issue in treating Achilles tendinopathy (3).

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The Editorial

PRP has been shown in dozens of randomized controlled trials to be effective (5-54). However, in the past few months, several papers that purport to show negative results have been published. What most people missed was that the third paper just published by JAMA this past week was accompanied by an editorial. This opinion piece stated (4):

“Platelet-rich plasma is an example of a promising laboratory discovery that was subsequently applied in human RCTs. However, the 3 RCTs published recently in JAMA suggest that translation of PRP from bench to beside has not yielded a successful new therapy for knee and ankle OA and Achilles tendinitis. Until a new generation of trials using standardized approaches to PRP therapy provides evidence of efficacy, it would be prudent to pause the use of PRP for OA and Achilles tendinitis.”

Huh? Four dozen positive PRP RCTs get trumped by three new RCTs all with the same serious flaw? Based on those flawed studies we have a university professor telling physicians they should stop using PRP? Who wrote this editorial and how can you scientifically support this statement? Why is this happening? Let’s start by answering the last question first.

Why Is This Happening? The Stakeholders

Business is often a game where there are winners and losers. To understand why this is happening to PRP, you need to learn about the business of drug development and its stakeholders. Let’s focus on developing a new FDA-approved drug for knee arthritis, a huge and growing market. There are several key players:

Bench scientists
Private companies/investment firms
Medical schools

I’ve already covered the role that bench scientists play in drug discovery. They begin with grant money paid by NIH (your tax dollars). About 40% of that goes to the university for admin fees and about 60% towards research. The university and bench scientists can then patent their lab discoveries.

As an example, let’s say a new gene therapy to help knee arthritis is discovered. A private company is formed by the university that licenses that patent and raises investment dollars. A hot CEO is hired who then partners with a university medical school to perform clinical trials. The company then pays the medical school to perform a study that will make up the FDA approval application.

As you can see, we now have a chain of stakeholders who have all bet the farm that this new therapy will be effective and be used widely by doctors to treat knee arthritis.

Why PRP Is a Problem for Our Knee OA Drug Stakeholders

From the moment grant money is paid by NIH to the moment a new drug application is filed for an FDA approval, many millions of dollars are spent. Hence, we now have stakeholders who are very sensitive to what’s already on the market to treat knee arthritis. If there’s one product that’s squarely in the craw of the new drug development pipeline for knee arthritis, it’s PRP.

PRP is cheap, already available on the market, widely used, and gaining acceptance. In addition, the FDA has stated many times that it’s leaving it alone. Meaning the FDA will not claim that PRP is a drug that requires approval. Finally, the fact that PRP has dozens of RCTs showing it works is a HUGE problem.

PRP is also knocking on the door for reimbursement by major insurers. This is a nightmare for any company developing new knee arthritis drugs. Why? You spent hundreds of millions developing your new knee arthritis therapy, hence, you need to get that money back for investors. Because of that investment, your new drug is likely to be at least 10X more expensive than PRP. In a health insurance world that loves cheap over expensive, while your drug may get FDA approval, it may have no market in which to live. After all, why would United Healthcare pay ten times more for a drug that works no better than PRP?

So if you’re a part of this drug development team, you need to get rid of PRP. How do you do that? I’ve already blogged on how the university lab scientists are seeding negative stories about PRP. However, given the wide popularity of PRP, that alone won’t get this done. You also need to chop PRP down, one bad study at a time, which is what we’re seeing.

The Author

Now let’s take the concepts above and see if they hold water in the real world. The name of the author of the recent JAMA editorial is Jeffery Katz, MD, MSc. I had no idea who that was so I looked him up. This is from his required conflict of interest disclosure for this editorial:

“Dr Katz reported receiving support from Biosplice as principal investigator of an observational study of osteoarthritis outcomes.”

What the heck is Biosplice? This is from their website:

biospice knee arthritis

Biosplice is a company developing a gene therapy to treat knee arthritis. So the guy who wrote this editorial about the three bad PRP studies is a university scientist who is taking grant money from a company developing a drug to treat knee arthritis. As I always say, you just can’t make this stuff up. This editorial is a direct example of the drug development stakeholder problem PRP now faces.

How These Three Negative RCTs Will Be Used

Realize that for insurance companies and policymakers, the most convincing research is a systematic review or meta-analysis. That’s where researchers take data from many studies and try to see what the whole body of literature tells us. The good news is that in these studies, the number of positive studies usually matters. However, you can also play with the criteria for which papers you accept or reject for your analysis. You can also weight certain papers more or less, depending on all sorts of subjective concepts. Hence, I would expect that researchers involved with the drug development teams are licking their chops over these new JAMA articles. They can be used, along with some creative inclusion and exclusion criteria to create new systematic reviews and meta-analyses that will show that PRP isn’t effective. That’s despite dozens of randomized studies showing that PRP works.

The upshot? IMHO the members of the university-business-pharma complex are hard at work trying to get rid of PRP. This isn’t a coordinated conspiracy, just individual stakeholders trying to protect their own interests. As a patient or physician that receives or uses PRP, will you let them get rid of this inexpensive and elegant solution to treat arthritis or will you expose the games being played? You know where I stand.

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