; and (2) if the investigations described in subparagraph (A) or (B) of paragraph (1) confirm that there is such a disparity, the labeling of the drug or biological product shall include appropriate information about the disparity. (b) Postmarket studies (1) In general If there is evidence that there may be a disparity on the basis of racial or ethnic background as to the safety or effectiveness of a drug for which there is an approved application under section 505 of this Act or of a biological product for which there is an approved license under section 351 of the Public Health Service Act , the Secretary may by order require the holder of the approved application or license to conduct, by a date specified by the Secretary, postmarket studies to investigate the disparity. (2) Labeling If the Secretary determines that the postmarket studies confirm that there is a disparity described in paragraph (1), the labeling of the drug or biological product shall include appropriate information about the disparity. (3) Study design The Secretary may, in an order under paragraph (1), specify all aspects of the design of the postmarket studies required under such paragraph for a drug or biological product, including the number of studies and study participants, and the other demographic characteristics of the study participants. (4) Modifications of study design The Secretary may, by order and as necessary, modify any aspect of the design of a postmarket study required in an order under paragraph (1) after issuing such order. (5) Study results The results from a study required under paragraph (1) shall be submitted to the Secretary as a supplement to the drug application or biologics license application. (c) Applications under section 505(j) (1) In general A drug for which an application has been submitted or approved under section 505(j) shall not be considered ineligible for approval under that section or misbranded under section 502 on the basis that the labeling of the drug omits information relating to a disparity on