How can I remove a striped pentalobe screw?

Hi all,

I have recently purchased an iPhone 6, 128gb space grey with a cracked screen. I need to remove the pentalobe screws to replace the screen and get the phone up and running.

Unfortunately the previous owner has completely stripped one of the pentalobe screws and I can not remove it with the correct tools. The screw has no shape left whatsoever (see photo) and will not grip at all.

I have tried different shaped screw drivers, the rubber band method and a stanley knife. I have heard to try super glue but I am scared it will seep into the thread and make it harder to remove. What is the best method to remove the screw?