Society of Toxicology (SOT)

Nelson Laboratories’ Experts Receive SOT Award

During the annual Society of Toxicology (SOT) meeting in Baltimore, Maryland, Michelle Lee and Audrey Turley from Nelson Laboratories were two of eleven authors awarded Best Overall Abstract for “Round Robin Study to Evaluate the Reconstructed Human Epidermis (RHE) Model as In Vitro Skin Irritation Test for Detection of Irritant Activity in Medical Device Extracts”. This abstract resulted in a poster presentation on the results of a worldwide collaboration to demonstrate the application of an in vitro skin irritation method for medical devices.

SOT_AwardThe acceptance of this method could significantly reduce the animal testing needed when determining the biocompatibility of medical devices. The initiative to reduce animal testing has primarily been led by Europe, but US regulatory bodies are adopting the initiative as well.

The irritation test is based on exposing RHE to device or material extracts, then performing a viability assay (using an MTT assay) where limits have been established to determine irritation potential based on an adopted method for chemicals from OECD 439: In Vitro Irritation: Reconstructed Human Epidermis Test Method.

Nelson Laboratories has been involved with this project long before it came to SOT, through our membership on the ISO working group for irritation. We have worked in conjunction with medical device manufacturers for this round robin. Look for a review of the official publication for this groundbreaking work in the near future.

In Vitro Skin Irritation Breakthrough To Revolutionize Medical Device Testing

Extractable Positive Control for In Vitro Skin Irritation Testing, SOT 2015

New research on extractable positive control for in vitro skin irritation testing of medical devices presented at 2015 Society of Toxicology (SOT) annual meeting. Click here to download in vitro skin irritation PDF poster.

Scientists at Nelson Laboratories recently returned from presenting new in vitro research at the 2015 Society of Toxicology (SOT) annual meeting with news that the future of in vitro testing of medical devices in the United States looks bright, and closer than previously anticipated.

Invited to present information about their discovery of, and subsequent research on, an extractable positive control material for in vitro skin irritation testing of medical devices, this breakthrough may offer the data FDA has been waiting for.

Nelson Laboratories, along with strategic partners throughout the world, have been developing and validating this alternative in vitro skin irritation test method for a number of years. Skin irritation is a condition caused by acute damage to keratinocytes following exposure to a chemical. Testing for the skin irritation potential of medical devices has typically involved the use of laboratory animals.

While in vitro skin irritation test methods have historically been shown to provide results consistent with in vivo data, they have involved the use of chemical solutions or spiked extracts as positive controls. To provide a method that more accurately mimics in vivo medical device testing methods, in which devices are extracted in polar and non-polar solvents, in vitro research has been focused on discovering an extractable material that will induce a positive skin irritation response in both polar and non-polar extraction vehicles.

Nelson Laboratories’ discovery that heat-pressed polyvinyl chloride (PVC) sheets infused with Genapol X-080 act as an irritant in both polar and non-polar fluid is a major step forward toward regulatory acceptance of this method. Nelson Labs is working closely with regulators to usher in this new era of medical device testing.

Download Nelson Labs’ SOT poster presentation to learn more about the scientific data behind Nelson Laboratories’ in vitro findings. You also read Nelson Labs’ press release, Scientists at Nelson Laboratories Discover Extractable Positive Control for In Vitro Skin Irritation Testing of Medical Devices.

Advances in in-vitro testing from the Society of Toxicology Meeting

Cell-Picture_1By Thor Rollins, Biocompatibility Specialist, Nelson Laboratories

While attending the annual Society of Toxicology meeting, I sat in on the Innovations in Toxicological Science symposium’s In Vitro Systems: Advancing Regulatory Science Through Innovation presentation. During this session the presenter discussed new in vitro methods that have been developed to test the safety and efficacy of new drugs and medical devices on human beings.

The cost of developing new drugs and medical devices is huge. The trends to better manage these costs involve making in vitro alternatives for making small-body systems to mimic what we would do with an organ or full body, sometimes called pseudo-humans.

With pseudo-humans, we can study a device or a drug to see how safe it would be before we take it to clinical trials, or test it on animals. This kind of system is faster at determining the safety and efficacy of pharmaceuticals and medical devices.

In addition, it can take years and millions of dollars to conduct tests on animals, but we know animals and humans aren’t directly correlated. So if we can come up with a system that is more predictive of safety, and is quicker and cheaper, we can move faster and be more confident of safety before moving onto clinical trials.

Pseudo-human tests are still in development, but a springboard test we already use at Nelson Laboratories is an in-vitro irritation test using dermal cells. Using stem cells, we grow a dermis to which we apply liquid that a medical device has soaked in. After application, we look for signs of irritation as a result of contact with the device.

We are currently working to get this in vitro irritation test to be a standard method for medical devices, so we no longer need to rely on animal testing. While this is not the same as using pseudo-humans for testing, it is a new form of testing already yielding positive results for Nelson Laboratories and our clients.

It has also become increasingly useful to utilize consultants when conducting tests. Their expertise aids in preventing unnecessary testing, which in the long run is less expensive and more productive for our clients.

Previously, we just performed the tests. Now, we are also focused on conducting safety assessments. We work with someone to determine the potential toxicity that would impact the patient, and consult with a toxicologist to determine what testing to do and examine the results. This prevents unnecessary testing and saves time and money in the long run.

We are currently working with a company with a device made of stainless steel. Together with a consultant, we looked at the process of making the device as well as the chemicals coming off of the device. By identifying these chemicals, we addressed the safety of the individual chemicals and determined which tests were needed and which were unnecessary. We conducted about two weeks of testing and research and eliminated the need for animal testing.  This not only saved time, but was also done at a fraction of the normal cost.

While many technologies are years away from being used on a regular basis, significant advances are taking place now.