(a) A commission agreement to accept a program benefit described by Section 549.0106:
(1) may not prohibit the commission from entering into a similar agreement with another entity that relates to a different drug class;
(2) must be limited to a period the commission expressly determines; and
(3) subject to Subsection (b), may cover only a product that has received United States Food and Drug Administration approval as of the date the commission enters into the agreement.
(b) A new product the United States Food and Drug Administration approves after the commission enters into the agreement may be incorporated into the agreement only under an amendment to the agreement.