I'll bite, against my better judgement...
Why would a pharmaceutical company not love this? They could help fund this and *gasp* make money! I would love to be the person who could spend some money and have my company's name on the cure for cancer. I guess you may be the type of person that believes Ford and Chevy have had that 100mpg carburetor locked up in a vault since the thirties too though...
In all likelihood the biggest hurdle this type of technology would have to clear is something like the FDA making approval a huge nightmare. See the epipen issues right now. There are products that do the same thing but the FDA hasn't approved them to administer the same medicine as epipen. Another issue I could see would be something like obamacare not paying for it because good old fashioned chemo is a cheaper treatment. Government is nearly the biggest hurdle to any new innovation these days. Not the same industries but look at Uber, AirBnB, and other products that people prefer to use than the existing options. Govt. has tried to shut them down in many cities because they aren't getting their cut.
The second biggest challenge to overcome is the people that believe the big pharma conspiracies. Maybe this will cure cancer but then what will the little machines do? Re-program brain cells to let the government mind control you? The anti vaccine, chemtrails, anti-gmo, flouride mind control crowd would probably crap themselves at the thought of smart technology being injected into people.