Each January, CMS accepts applications for new HCPCS codes. CMS holds a public meeting in May-June, releases preliminary decisions in early September, and releases final decisions about Thanksgiving.
The only easy category is codes for new intravenous drugs, and each year there are quite a few of those.
For other therapies and equipment, it's a cold harsh process. CMS has released its coding decisions for CY2018, on the HCPCS website, here. I've also put the 5 PDFs in one zip file in the cloud, here.
It was a strike-out for all three diabetes technology codes I was tracking. No code for the Medtronic 670G artificial pancreas; no code for the associated, PMA-grade glucose strips or high accuracy PMA-grade meters, and no code for a telemedicine scale used in diabetes prevention programs. Dexcom also lost its attempt for more specific battery coding for the Dexcom G5. Nearly all of several dozen other equipment or supply code applications failed.