From bench to bedside: an inside look at biotech research on a new wound care treatment

Wound care treatment is evolving and a new technology could get the approval of the U.S. Food and Drug Administration (FDA).

FDA review of a biologics license application marks a years-in-the-making milestone for PolarityBio. The Salt Lake City-based biotech firm is developing SkinTE, a technology to treat diabetic foot ulcers using samples taken from a patient’s own skin, then processed and reapplied directly to the wound.

The timing matters. The wound care space has spent the past several years under a cloud of regulatory scrutiny following questionable treatments and billing — and possibly fraud — involving skin substitutes. The situation has left some providers uncertain about treatments they can use and trust. In conversation with Medical Economics, PolarityBio President and Chief Medical Officer Ned Swanson, M.D., explains how SkinTE works, where the company stands in the FDA review process, what new CPT billing codes mean for providers, and how the recent shake-up in wound care reimbursement may be opening the door for more rigorously vetted technologies.

This transcript has been edited for length and clarity.

Medical Economics: Our primary care physician audience, they get up every day and go to work seeing patients. They may not be familiar with the research and development that goes on at a biotech company. What does a typical day look like for PolarityBio?

Ned Swanson, M.D.: It's exciting. Every single day we feel like we're putting in all the work we can to help solve a broad problem for patients. And if you think about medical research a lot of your audience might be familiar with what they see coming out of labs, the real bench research, where things start and where the innovations begin. In the biotech day-to-day work, we're trying to really translate that into a practical daily use medicine. So how do we take those innovations that work really well in the controlled lab environment and translate it into a product that can actually be used repetitively over and over for patients that need it? What we do day to day can really shift with where we are in the company's life cycle. Right now, we are head down, laser focused on submitting for FDA approval. So we've been very focused on running clinical trials for the past few years and also getting the manufacturing up to where it needs to be before an FDA decision. And right now, we've completed all of that work, and we're compiling it all to bring to the FDA. But as you start to get past one milestone, you're then looking toward the next. So we're also planning for the future of, if we get FDA approval, how are we going to bring this to market? Who are the best patients that fit for this treatment? Who are the providers seeing and treating these types of patients? Where are they located? What are their practices like? A lot of that work has begun. It's a very different day depending on where we are in that life cycle.

Related coverage: Healing from within: Biotech and the future of wound care

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Medical Economics: Current wound care products, as I understand it, are often called skin substitutes that use donor or lab grown tissue. Can you explain how SkinTE differs from that?

Ned Swanson, M.D.: The biggest differentiator is using the patient's own skin. You have those two big options:Use the patient's own tissue and cells, or use cells and tissue from another human, an animal or a synthetic process where you make something in a lab. We really believed in taking the autologous approach of using the patient's own tissue and cells, because your body accepts those and that's able to engraft, essentially heal, to the body, then it's able to grow within the body. What that translates to for patients is our product is designed to be a single treatment. You have a wound, if it gets to the point where the patient provider wants to use SkinTE the expectation would be, would only need one treatment. In our trials, we've allowed up to two treatments, but only 10% to 20% of patients ever needed to have a second treatment during the trial time. That is a huge differentiator compared to the other products on the market you described, where they're not using the patient's own cells and tissue. Those need to be applied many times over and over because your body has evolved to recognize things that's not itself. When you put tissue on the body from another human, another animal, it recognizes that quickly and eventually rejects it, or if it's a synthetic matrix that made in a lab, those are all essentially resorbed and absorbed by the body over time. That's the biggest differentiator in our product, is that we're giving the patient their own living activated cells back to the themselves, which are able to permanently engraft and heal into the wound.

One way to think about it as well, skin substitute type products are kind of just trying to whip an exhausted horse. It's a crude analogy, but you have a wound, it's a chronic wound, it's been there for a long time. The cells and tissue around the wound have proved they've exhausted their ability to heal and a lot of those skin substitutes are just providing a bolus of growth factors, or stimulation to try to wake it back up to close. Whereas our product works by taking healthy skin from somewhere else on the body, so the skin is not coming from that chronic wound environment. And then when we manufacture the product, it actually activates all the cells into a wound-healing state. This is something we have to test for every time we send a product out the door, to ensure that our manufacturing process has turned on wound healing pathways within those cells where they're ready to heal. Then that goes in the wound, so you're directly contributing healthy, active cells to the wound in a place that really hasn't had that present for a long time as a chronic wound, by definition, has been there for months already.

Medical Economics: Can you explain a baseline of where you're at in the process with FDA reviews and approvals?

Ned Swanson, M.D.: SkinTE is for investigational use only, meaning that we haven't received FDA approval yet, but we have finished our phase three trial, and we have now collected all that data, and we're compiling it all to submit for the FDA decision for a biologics license application (BLA). It's very similar to a drug approval, but for a biologic drug, so things that you see with antibodies and cell therapies are considered biologic. We're putting that all together to submit for review, and then that will undergo review by the FDA over the following eight months after we submit it, and we'll have a decision from the FDA probably early next year if we stick to those timelines.

Medical Economics: There was a milestone earlier this year with the American Medical Association publishing CPT codes related to SkinTE procedures. Can you explain what that is?

Ned Swanson, M.D.: It was an exciting milestone for the company. With our product, SkinTE, it's an autologous product, meaning it's made from the patient's own skin. So the provider using SkinTE takes a small sample of full thickness skin from the patient, which gets sent to us in Salt Lake City. We turn it into SkinTE it gets sent back. It arrives in a needleless syringe, and it's almost a sticky oatmeal consistency that they apply to the wound bed dress with normal dressings, andit goes on to heal within the wound. Those CPT codes that we received are related to the procedures involved in using the product. There's two separate procedures happening at two different time points. When they take the full thickness skin sample that there are codes now that describe the work involved with taking that piece of skin. And then when they receive the product back and they apply it to the wound, there are now codes specifically available to use for that procedure related to applying the product to the wound. Getting those codes is a huge stepdefinitely something we need to have in place as we get closer to coming to market. That will allow providers to bill for their work related to those procedures, in addition to codes that would be reimbursed for the product directly.

Medical Economics: When we talk about skin substitutes and wound care, there's been a spotlight on that medical treatment in recent years because of skin substitutes. The fraud cases that have come to light have put enormous regulatory scrutiny on anyone operating in the wound care space. What has that been like over the last two or three years?

Ned Swanson, M.D.: It's certainly been interesting. With us being in this FDA pathway, pursuing a full blown BLA approval for SkinTE, doing all the rigorous clinical trials under the oversight of the FDA, we've been a little bit outside of it, because that's been going on in the commercial market space, but we're obviously a part of the wound care field. We're very well connected and it's been tough for everyone involved, both industry and providers, because if you actually look at what happened, it's probably a very small fraction of outliers that abuse the system. But they abused it to the point that they made up a majority of the market in just a few short years, and actually forced Medicare's hands to make changes. They definitely came down hard on space, and all those changes they made with reimbursement for those products went live in January of this year. From what we gather over the past few months, with these new changes in place, providers have really been left with a challenge to know what they can and can't use for their patients, if they're going to be getting in trouble for doing what they think is the right thing, based on what's happened in the past. And I think they're really looking for new, innovative products to come to market and to come to market through all the pathways that they feel have already been scrutinized and reviewed by agencies like the FDA, by CMS (the Centers for Medicare & Medicaid Services), and I think they're looking to move forward with treatments for their patients. If they've run into challenges now with skin substitutes, then maybe it's time for for new technologies to move in and fill that void, for sure. I think it's going to be a rough patch over the rest of this year, and maybe a little bit going forward from there. But we see this whole field moving more towards products coming through pathways like the FDA BLA pathway that we're doing. There's a few products a step behind us, just finishing or within phase two trials. So it does seem like there may be a wave of more and more products coming down the pipeline.

When you really look at what happened there, there wasn't a lot of innovation taking place with the actual products coming to market. It was a lot of copycat products that were essentially the same technology going down pathways of regulation appropriately, but very easy pathways of regulation that didn't have a lot of barriers to going to market. With not a lot of barriers going to market, suddenly, there were over 200 skin substitutes on the market. And you could probably put all of those 200 products in three to four buckets of, what are they? Is it a scaffold? Is it an amnion? Is it a tissue? You could probably categorize all of them in just a few buckets of types of technology and the newer products coming to market that didn't really change anything fundamental about the technology. They just started increasing prices, so suddenly you had a product that looked identical. One might cost $100 a square centimeter, and one cost $7,000 a square centimeter, and there was no apparent reason for that. It's going to be a hard transition. It is a hard transition, but CMS got their hand for us on this one.