Dr. Larry Benowitz has been in the forefront of research when it comes to optic nerve regeneration for a while and has written many white papers about it. You can also watch a video of him talking about the subject $1. The context is glaucoma, which is a collection of diseases that cause the destruction of optic nerve axons and the subsequent death of retinal ganglion cells that form the optic nerve, but it applies to all cases of optic nerve damage as far as I know.

Personally, and as someone who's been blind due to optic nerve damage caused by glaucoma for over 5 years, I wouldn't bet on a cure being available during my lifetime because science advances very slowly as far as the average human lifespan is concerned.

Hallo 👋🏼 partially blind girl here.
I was actually born with optic nerve hypoplasia (meaning the optic nerve just stopped developing)in one eye, so I’ve never had any vision in my right eye.
Overall, the eye reacts to light and I have feeling in it, but I have absolutely no vision-no shadows, nothing.

Honestly, it’s not ever really been a big deal to me...I can drive, play sports, etc. I don’t have any actual restrictions. I will say that it sucks not having the peripheral vision (especially when someone comes up on that side and scares the shit out of you 🙄 although most of the time you can feel their presence-slight change in the air, maybe?), and I have to watch it with sunlight. Sometimes the sun will be shining only in the eye I’m blind in and I don’t notice until it starts getting painful!

Also, my eye doc was reeeeeallyyyy hesitant to let me wear contacts (obviously) because a single eye infection could cause you to be completely blind for the rest of your life, but he eventually allowed it (on the pretense that they would only be used during gymnastics because my glasses kept flying off, but he knew better).

I feel for your friend, though. I’ve always thought, “if anything, at least I was born this way and don’t have to adjust”. I couldn’t imagine having sight and then one day losing it.

As far as research, it’s a tricky one. You can find general articles online and I check up on it every five years or so but not much has changed. There are BILLIONS of optic nerves, making any restoration or surgery insanely difficult. It might be a possibility if your friend has enough nerves left, but otherwise......
There’s just no way for us to replace so so many tiny, complex electrical wires with our current technology. I’ve read research that suggests using stem cells could provide a viable possibility, but that research is still very young and, well, all the “killing babies” nonsense is kinda holding everything up.

Best of luck to your friend! I imagine it’s seeming like the worst possibility to them, but seriously. It’s completely doable- the brain can adjust to many things! And after so long, it’ll seem normal. Hell, I’ve become so used to it I forget to note it on medical records now 😅 feel free to message me with any questions!

Your best bet may be to set up NIH and Google alert for research. There are some devices under development that bypass the optic nerve, but I’m not sure if he would be a candidate since he can see with his other eye right? Glad he is still able to see, drive, read, etc.