Google’s smart contact lenses partner Novartis has abandoned plans to start testing its autofocus contact lens on people this year.

Despite assurances that its product with the search giant is ‘progressing steadily’ a spokeswoman for the brand revealed in an email that it was “too early to say when exactly human clinical trails for these lenses will begin”.

Novartis and Google teamed up two years ago with the lenses now being developed with Google parent company Alphabet Inc.’s life sciences unit. In 2014, Novartis chief executive Joe Jimenez said the company hoped the lenses would be on the market within five years and stated last year the product was on track to begin testing in 2016.

“This is a very technically complex process and both sides are learning as we go along,” claimed the spokeswoman adding, “we will provide updated at the appropriate time.”

Two kids of smart lenses are in development, an autofocusing lens for those with long-sightedness and another for measuring blood glucose levels in diabetics.