I think they can be corrected in the following way:
1. Whichever a drug company comes up with something, it is guaranteed to make a fortune.
2. A reflex action is one that is unconsciously controlled.
Am I right?
What is the first one supposed to mean? "Whichever" is definitely not the correct word, but the replacement/change is not clear to me, because I don't know what meaning you want to express. It could be
however, implying the methodology the drug company goes about 'coming up with something', or it could be relating to a specific drug, in which case it'd be better to say
whatever a drug company comes up with. So, that can't be answered without more information.
Your second example (with the added
is) is the correct one. In some cases you'd want to say
reflex action but if you are just using
reflex as a quantifier to the type of action in a general sense, then it sounds better (to me) to use
reflexive action.
