OcculLogix (San Diego) reported that a peer-reviewed article published in the current issue of Contact Lens & Anterior Eye, a journal of the British Contact Lens Association (London) has provided further validation of the TearLab Osmolarity System's ability to accurately measure subtle changes in the condition of the ocular surface.
According to the article, the TearLab system is beneficial over previously existing technology because it is designed to be used in an eye doctor's office, has “great ease-of-use“ and requires a very small volume of tears.
“While tear osmolarity has proven to be the most accurate method for diagnosing and following dry eye disease patients, the challenge has been to conduct the test quickly and efficiently,“ the authors wrote. “Until recently, the test was typically performed in a clinical laboratory setting and required large samples of tears; this was often a challenge in patients with severe dry eye.“
The TearLab system uses a lab-on-a-chip approach that requires less than 50 nanoliters of tear fluid in order to measure tear osmolarity, Tracy Puckett, the company's VP of marketing, told Medical Device Daily. She explained that the system eliminates the challenges that previously prevented point-of-care osmolarity testing. The TearLab system can produce a sample-to-answer result in less than 30 seconds, according to OccuLogix.
“What we're doing is analyzing biomarkers in tears,“ Puckett said. The problem, prior to the TearLab system, is that “we don't have much tear fluid,“ she said, so it was impractical to use tears for this purpose.
So first the company had to overcome the obstacle of sample volume. Then, because the test only requires a very small sample, the company had to develop the tear testing system as a point-of-care diagnostic, so that the samples could be analyzed quickly, before the tears evaporated, Puckett explained.
At the core of TearLab is a disposable lab-on-a-chip that functions as both a tear collection device and a measurement system, the company noted. Consequently, tears are collected directly from the eye, eliminating the need for a standard glass capillary tube, and embedded nanofluidic channels move the tear sample to the measuring electrodes.
Dry eye disease is a common condition in which the eye does not produce enough tears to keep the surface of the eye sufficiently lubricated. It affects nearly 40 million people in the U.S. and 100 million people worldwide, according to the company. In its mild to moderate forms, it can impact vision and the ability to go about daily activities. In its more severe forms, the disease can lead to permanent loss of vision.
Puckett said it was a third-party study that OccuLogix was not involved with. Abbott Medical Optics (Santa Ana, California) sponsored the study to evaluate its Blink Intensive Tears product compared to other commercially available lubricant eye drops for the treatment of mild, dry, irritated eyes.
The study “validates that the instrument can be used as a tool in evaluating treatment decisions,“ Puckett said. “It's a great position to be in because we are just a catalyst to other companies being successful.“
The study compared Blink to Cellufresh from Allergan (Irvine, California), and Systane from Alcon Laboratories (Fort Worth, Texas). The study enrolled 60 patients, with 20 patients in each group. Tests performed during the study included Schirmer, tear-film break-up time, visual acuity, fluorescein staining, tear osmolarity and wavefront aberrometry, the authors noted. Osmolarity testing was performed before instillation of the lubricant eye drops and then a final time five minutes after the drops were put it in.
According to the researchers, the assessment of tear osmolarity provides the most “objective, measurable test for determining improvement in dry eye patients.“ The instillation of any artificial tear or lubricant eye drop should decrease the tear-film osmolarity. The results found that Blink significantly improved tear osmolarity compared with the other two products in the study.
Puckett said that TearLab is a platform technology and that the company hopes to eventually expand the indications for its use, to be able to do tear-based testing of other diseases with the system. She said the company has not yet decided which additional indications it will pursue though.
The TearLab system is the first quantitative and objective test for dry eye disease, Puckett said. She noted that there are some quantitative tests available for the disease, but those tests are subjective. She added that osmolarity is the only test that correlates well to disease severity. About 95% of patients with dry eye disease are in the mild to moderate range, Puckett said.
“As evidence continues to mount that tear film osmolarity is the preferred tool in the evaluation of patients suffering from [dry eye disease], we are thrilled to be able to make our proprietary lab-on-a-chip technology available in most European countries as well as the U.S. and Canada,“ said CEO Elias Vamvakas.
Puckett said the system does have FDA 510(k) clearance in the U.S., and the company is currently in the process of obtaining a CLIA waiver. She said that about 300 of the instruments are out now in eye doctor's offices so that the physicians can become familiar and comfortable with the devices.
Amanda Pedersen, 229-471-4212;