Time sure does fly by when you’re having fun. And this week is no exception. We spent a good portion of the week getting ourselves ready to begin work on making a drug-eluting access graft that we proposed for KidneyX. This entailed having discussions with key collaborators (Drs. Yael Vin, Nikhil Agrawal and Mauricio Contreras) on the program to develop and refine our project plan, get our lab in order (we scientist tend to be pack rats so we needed to do some housekeeping) and set up the internal logistics. While that may seem a little tedious/boring (and compared to performing the research, it is), it is so critical to conducting a successful study.
Developing a drug-eluting device is an area that we have a lot a familiarity with, having patented this process. We just received news from the US Patent and Trademark Office that two continuation-in-part applications we submitted to expand our current patents were accepted. This is great news and you are learning about it here first (what better reason to read this blog). You may be asking yourself, what does he mean by drug-eluting and why is this process any better than what is offered from devices like drug-eluting stents? To answer this, I need to go back to the beginning in terms of giving you a simple overview of electrospinning.
While you can learn a lot more by visiting our website or by reviewing publications, I figured I would break it down in simple terms. When I give presentations about the process, I like to give the visual of equating electrospinning to Spider-Man shooting his web. Our process, while a little more complex, is similar in that pellets of a medical polymer (these materials are used in items people know like clothing and hardwood floor coatings except at a much higher grade) are dissolved in a solution and run through a tube with a needle at the end that is exposed to a high voltage. The polymer gets “charged” at the needle, gets pushed out and heads to a grounded collecting surface to form a material or device. Like Spider-Man, the resulting material is made from very tiny fibers that make a bigger material. For our purposes, these very small fibers (over 40 times smaller than a human hair) are similar to the structure the body uses to hold your cells in place so the body reacts well to this material in early preclinical studies. This is the basis of what we do, the reason for this blog’s name.
Drugs are commonly used by all of us and are typically taken by mouth or injected to treat a specific disease. So, if you have an infection in your foot, you take an antibiotic that goes throughout your whole body to treat your foot. Doesn’t really make sense does it? This process can have unintended side effects, some of which can be pretty bad. Unfortunately, there is no better process at the moment. For devices, we believe that delivering the drug right at the problem area would eliminate these issues and be a more effective treatment. Remember the electrospinning process I just described. Prior to making the fibers, a target drug can be added into the solution so when the fibers are made at room temperature, they include drug throughout each fiber making up the device. Drug is released when implanted in the body. I typically equate this release process to when you put red garments in the white clothing load and everything turns pink. Again, there is more science to it but this is the gist. Using electrospinning, you can really tailor drug delivery to specific areas within the device (i.e. inner wall, one side of the device). The premise of a drug-eluting stents used in cardiovascular applications is similar, except these devices rely on a polymer coating that holds the drug to break down in the body, which can be less controlled. It is also harder to put the drug in a specific area within that device, which our technology allows.
For this KidneyX program, we are proposing to incorporate a drug used in stents into our electrospun access graft device. We plan to place this drug in the device only where most problems occur, which is where the blood flows from the graft into the patient’s vein. The goal is to direct the cells in the vein to stop overgrowing in the area so that blood can flow freely. We have been able to incorporate this drug before into our material and show that it can target these cells both at the benchtop and in preclinical studies. Now, we get more specific to just put it right at the problem area. We are excited to begin this process and will look to provide updates as they become available.
Have a great weekend!