NEW YORK – If platelet-rich plasma is good enough for Kim Kardashian, what more do you need to know?
Turns out, there’s plenty to know, and plenty more that remains unknown about the procedure, which is sometimes referred to as PRP or, in Kardashian’s case, as a “vampire facial,” according to Terrence Keaney, MD, of the department of dermatology, George Washington University, Washington.
Dr. Terrence Keaney
It’s easy to make: draw blood, centrifuge it, and then deliver it. The platelets themselves are not the active substances. For that, you have to look at what the platelets release from their alpha granules. They include a wealth of growth factors, including platelet-derived growth factor, transforming growth factor, vascular endothelial growth factor, epidermal growth factor, fibroblast growth factor, and connective tissue growth factor.
That’s not all. “There are 800 other bioactive molecules secreted by platelets,” including cell adhesion molecules, cytokines, antimicrobial peptides, and anti-inflammatory molecules, said Dr. Keaney, founder and director of SkinDC, in Arlington, Va. “You bring it all together, what is PRP? A growth factor/cytokine cocktail.”
But, like the cocktails one can find in a college dorm, compared with the ones found at a bar at an upscale hotel, there can be big differences – depending on who’s doing the mixing.
Still, its reputation as an all-natural, safe product has made it appealing to the public, as well as to doctors in fields beyond dermatology, he said, citing sports medicine, dentistry, otolaryngology, ophthalmology, urology, wound healing, cosmetic medicine, and cardiothoracic and maxillofacial medicine.
The Food and Drug Administration considers it a blood product, which means that it is exempt from the FDA’s traditional regulatory pathways, which would require animal studies and clinical trials. Instead, oversight falls to the FDA’s Center for Biologics Evaluation and Research, which is responsible for regulating human cells, tissues, and cellular- and tissue-based products.
A number of device makers have used the 510(k) application to bring PRP preparation systems to market. Under the application, devices that are “substantially equivalent” to a currently marketed device gain FDA clearance (J Knee Surg. 2015 Feb;28[1]:29-34). The result is that many such systems are available.
Nearly all of the devices have received clearance to produce PRP for use with bone graft materials in platelet-rich products for use by orthopedic surgeons. Other uses of the product, like stimulating hair growth, would be considered off-label.
Nevertheless, the purveyors of PRP have found people willing to part with their money in exchange for the hope that they may be able to hold on to their hair. That is not surprising, given the “pretty meager” therapeutic armamentarium available to them, Dr. Keaney said, citing minoxidil and finasteride – each of which was approved more than 20 years ago.
He bemoaned the lack of standardization for everything from platelet preparation technique to potential applications, which include facial rejuvenation, wound healing, and hair loss. “PRP has hype and it has hope, but it needs help,” he said. “There are lots of clinical questions that need to be answered.”
He added that the data remain thin. “Unfortunately, our clinical data does not match the hype around PRP,” he said, citing a recently published meta-analysis of six studies involving 177 patients (J Cosmet Dermatol. 2017 Mar 13. doi: 10.1111/jocd.12331).
Its conclusion was measured: “Platelet-rich plasma injection for local hair restoration in patients with androgenetic alopecia seems to increase hair’s number and thickness with minimal or no collateral effects. However, the current evidence does not support this treatment’s modality over hair transplantation due to the lack of established protocols,” the authors wrote. The meta-analysis results, they added, “should be interpreted with caution because it consists of pooling many small studies and larger randomized studies should be performed to verify this perception.”
Questions include how to determine the proper concentration and how many times PRP should be centrifuged, Dr. Keaney said. And it is not clear how or how often to deliver PRP. Subdermally? Via microneedle? Both? After traumatizing the skin to increase endogenous activators? Daily? Weekly? Monthly?
“We don’t know,” he said.
And, Dr. Keaney acknowledged, that may not change. “There is little incentive for industry to do a large-scale study,” he said. “If the results aren’t what they look for then you’ve killed your golden goose.”
Still, he has not been dissuaded. “From my standpoint, there’s a good scientific rationale, a proposed mechanism of action, molecular pathways.”
Though the clinical data have been variable, the studies small, and the study designs inconsistent, “there is a trend towards clinical effect,” he said. “If this is done appropriately, using appropriate systems and protocols in your office, this can be a very safe procedure – with injection site discomfort,” he said.
Dr. Keaney has spoken on behalf of a PRP preparation manufacturer.