MPMN_Medical Product Manufacturing News

Medical Product Manufacturing News, September/October 2015

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Q M E D . C O M / M P M N M E D I C A L P R O D U C T M A N U F A C T U R I N G N E W S S E P T E M B E R / O C T O B E R 2 0 1 5 1 9 Currently, we are working on three different tests for the in vitro sensitization method to gather the endpoints: the Glutathione Reduction Assay, the ARE Gene Expression, and the LDH Cytotoxicity Assay or MTT. With three tests, the question becomes how do you use three tests to predict sensitization? Answering this question has created controversy in the industry. Some labs have developed algorithms that use the three in vitro sensitization test endpoints to predict sensitization. EURL ECVAM is looking at these endpoints (among others) and working to validate each of them against animal tests to determine which procedure or combination of procedures most accurately mimics the potential clinical application. What method will win out in the end is to be determined. Current in vivo sensitization testing accepted by FDA commonly involves the guinea pig maximization test. Turnaround time on this test is eight to nine weeks. Because sensitization testing dictates repeat exposure before a biological reaction can be observed, the guinea pig maximization test is the most expensive of the Big Three tests. In addition to limiting animal testing, it is the elimination of this expensive, multi-week test that makes the potential benefits of in vitro sensitization so impressive. Cytotoxicity Testing Is Already In Vitro in U.S. The cytotoxicity test is one of the biocompatibility tests currently performed in vitro and accepted by the FDA. Cytotoxicity testing is performed using mouse fibroblast cells, also known as L929 cells. The cells are a nice test platform because L929 cells are adhering cells, meaning they naturally adhere to the walls of the testing flask used to "farm" the cells. The cytotoxicity test excels in many areas. It is the most sensitive screening test option available. It is also the quickest and the least expensive, primarily because it is an in vitro test and testing done with cells that develop quickly. This eliminates animal acclimation, which generally takes more time. If you want to analyze a product or material in the R&D phase, cytotoxicity testing is a particularly sound option because it is cheap, fast, and super sensitive. You will know if you have an issue, and it will allow you to make the necessary adjustments for better testing outcomes once the product is ready to go to market. What Does This All Mean for Device Manufacturers? All medical device manufacturers must conduct biocompatibility testing. Current biocompatibility test methods generally mean a long, expensive testing process. Once approved by FDA, in vitro testing offers manufacturers a more timely and cost efficient alternative which will also reduce animal testing. Testing that normally takes anywhere from eight to nine weeks can be reduced to two to three weeks thereby significantly lowering costs. Nelson Laboratories has been conducting in vitro tests for over 20 years, and is actively involved in working with FDA and ISO 10993 representatives to ensure that when in vitro sensitization and irritation method development is complete, the FDA will recognize and accept those submissions. Standard shrink ratios: 1:3 1:6 Custom Sizes Cut to length Scored on 2 sides (optional) Easily Removable Precision matters. 26608 Pierce Circle, Murrieta, CA 92562 800-618-4346 | PH: 951-698-4346 | FX: 951-698-4347 Facilities: California | Minnesota | Texas Please contact us today for samples, quotes or questions: Medical Extrusion Technologies-Texas, Inc. (MET-Texas) FEP Heat Shrink Tubing The precision quality and consistency of the FEP heat shrink you use matters. Just as important, working with a partner well-versed in sophisticated medical device industry standards. MET maintains precise, low elongational growth and consistent recovery results for I.D. and wall thickness. Manufactured at time of order to your exact specifi cations. Precision also comes with industry leading lead times, competitive pricing, and the service levels you require. Need FEP? Contact MET. MET Heat Shrink: ä%HVWLQ3HUIRUPDQFH ä%HVWLQ&ODULW\DW([SDQVLRQ ä%HVWLQ)LQLVKDW5HFRYHU\ ä)LQLVK)LUVWZLWK)(3IURP0(7 TM See us at MD&M Minneapolis, Booth #1058 Medical device extract is added to the surface of reconstructed human epidermis (RHE) for in vitro skin irritation testing. In vitro biocompatibility testing of medical devices will provide a quick and reliable alternative to animal test methods.

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