Relative to changes to health benefit plans that cause certain covered persons to switch to less costly alternate prescription drugs. A health carrier, health benefit plan, or utilization review organization shall not limit or exclude coverage of a prescription drug for any covered person who is medically stable on such drug as determined by the prescribing health care professional, if all of the following apply:

(1) The prescription drug was previously approved by the health carrier for coverage for the covered person.

(2) The covered person’s prescribing health care professional has prescribed the drug for the medical condition within the previous six months.

(3) The covered person continues to be an enrollee of the health benefit plan.