A health benefit plan issuer or pharmacy benefit manager may not include a drug on a maximum allowable cost list unless:
(1) the drug:
(A) has an "A" or "B" rating in the most recent version of the United States Food and Drug Administration's Approved Drug Products with Therapeutic Equivalence Evaluations, also known as the Orange Book; or
(B) is rated "NR" or "NA" or has a similar rating by a nationally recognized reference; and
(2) the drug is:
(A) generally available for purchase by pharmacists and pharmacies in this state from a national or regional wholesaler; and
(B) not obsolete.