Four years ago, Google’s medical research arm announced “a smart contact lens that’s built to measure glucose levels in tears.”¹ The device was to accomplish this “using a tiny wireless chip and miniaturized glucose sensor that are embedded between two layers of soft contact lens material.”¹ In the years to follow, Google’s parent company Alphabet would kick the project over to its life sciences division, Verily, and partner with Alcon to continue exploring the possibilities. This week, the companies announced the project has been put on ice indefinitely.²

“Our clinical work on the glucose-sensing lens demonstrated that there was insufficient consistency in our measurements of the correlation between tear glucose and blood glucose concentrations to support the requirements of a medical device,” explains Verily’s Chief Technical Officer Brian Otis, PhD, in a statement released Friday.²

In the announcement, Dr. Otis noted a few specific stumbling blocks, including “interference from biomolecules in tears [that] resulted in challenges in obtaining accurate glucose readings from the small quantities of glucose in the tear film. In addition, our clinical studies have demonstrated challenges in achieving the steady state conditions necessary for reliable tear glucose readings,” he said.²

However, although glucose monitoring appears to be a dead end, the developers were able to make some in-roads with smart lens technologies. For instance, the companies report they’ve been working on a smart accommodating lenses for presbyopia and even a smart intraocular lens.²

Google’s ‘Smart’ Lens for diabetes. Rev Optom. www.reviewofoptometry.com/article/googles-smart-lens-for-diabetes. February 15, 2014. Accessed November 19, 2018. Otis B. Update on our Smart Lens program with Alcon. Verily. blog.verily.com/2018/11/update-on-our-smart-lens-program-with.html. November 16, 2018. Accessed November 19, 2018.