HHS’ proposed overhaul of drug rebates is expected to lead to higher Medicare Part D premiums, but CMS is helping insurers keep premiums artificially low by letting them choose to have taxpayers cover the cost of setting premiums too low for the first two years, sources say. Without the newly planned demonstration, the upcoming rebate rule would likely cause premiums to rise right before the 2020 presidential election. The deadline for insurers to submit bids for next year is June...