Been on finasteride for 6 years - will it continue to work for many more years?

26 years old. Will finasteride continue to work for many more years for me? I've been on finasteride since august 2017. I was 20 years old and a Norwood 5 level. I had good regrowth first year to now I'm a nw3 vertex. I've notice that it's thinned compered to when I first got on finasteride the first year. Will finasteride continue to work for me at least slowing down the loss for more years? Thank you