This is so many generations later it hurts, but there was a game by konami that I guess was an rpg. Anyway you were in a mech going down into the moon investigating whatever strange things were happening; all I remember as from my childish memories is that it was actually interesting as the people you know started to change/ get infected. It wasn't anything groundbreaking, but I remember actually being scared by it, and now I can't remember it for the life of me. Oh it was for the playstation, so shoot me if it's too un-indie.
I thought I remembered something like this on the Amiga, called Bio-somethingorother with a green wireframe head on the front cover. Then I did a search on MobyGames and came up with this
which is something completely different but seems to match your description... ahh well.
The one I was thinking of was a little more like System Shock crossed with Hired Guns, but then again I could be completely making that up. Could be an awesome game though...
[EDIT: A little more searching comes up with Captive 2
(which has BioCorp in it, so I was close enough).]