The adoption rate for the Cygnus Biographer was not very good, in part because of poor management. The assumption at Cygnus was that once they had approval, someone would purchase them. They had no real distribution outlet and ended up settling for an agreement with Sankyo Pharma, which of course is not the thing to do if you are trying to penetrate the diabetes testing market.
As it relates to Medtronic MiniMed, there marketing plan is really driven towards insulin pump adoption. Although Al Mann, the founder of MiniMed, was working toward the artificial pancreas, the lure of money was too great --- and who could blame ~$4B!
For those who are unfamiliar with the market area and are looking for a buyout, you should know that Bayer, Roche and Abbott all have internal programs for developing similar continuous monitors that will likely lead to additional IP questions. JNJ is the only group that I am not certain about regarding a continous monitoring program, although I am certain something is going on at Lifescan.
As it relates to Big Pharma, they abandoned devices many years ago. The only one who has begun to show interest is Pfizer as can be seen with Exuberal, the inhaled insulin.