Unfortunately things are not that symmetrical... just as it is much easier to make a missile that can get through any given missile defense system than it was to make that defense system, it's many orders of magnitude easier/cheaper (if at all practically possible) to create stuff that causes an incurable lethal condition than it is to create an antidote. (And the root causes of it all are very likely quite fundamental and unbypassable, consequences of the 2nd law bubbling up the matter complexity chain...)

I'd advise against doing more search on these topics if you want to sleep well at night and/or if you don't think you're already on one "naughty list" or another ;)