Regarding apoptosis and inhibitors
Apoptosis is very tightly controlled for obvious reasons. Setting it off without proper control would result in the uncontrolled loss of cells. Apoptosis is one of the major pathways which are either mutated or shut-off in cancers, preventing the body from eliminating malingnant cells. These two papers are interesting in this context:


Apoptosis: A Review of Programmed Cell Death
The role of apoptosis in cancer development and treatment response


In this context it makes no sense to have a shut-off mechanism once the apoptosis cascade has started. It is only set off when there is a real reason (and is well controlled), so I don't think there a "null-apoptosis" mechanism. It would of course still be possible to artificially make substances, that inhibit parts of the activation cascade. But besides for apoptosis research I don't see any use for it. There is actually some research going on to find out how to activate apoptosis again in cancers.