FDA's NEW POLICY ON SUPPLEMENTAL ANDAs FOR "BP"-RATED PRODUCTS REQUIRES IN VIVO BIOEQUIVALENCY DATA, MAY UPGRADE RATING TO "AB"

Generic drug companies must conduct in vivo bioequivalency studies for changes in formulation or manufacturing site of "BP-related" generic drugs under a new policy at FDA's Division of Bioequivalence. In the past, FDA only required dissolution data in ANDA supplements for products rated in the Orange Book as "BP" -- oral and injectable products with potential bioequivalence problems. FDA Bioequivalence Division Director Shrikant Dighe, PhD, announced the new policy at a Sept. 16-17 APhA symposium on bioequivalence issues held in Bethesda, Md. "The agency is now considering that deferral of in vivo bioequivalency studies no longer be granted for changes of formulation or facility . . . for products which are coded 'BP,'" Dighe said. He noted that "in the past," deferral "of in vivo bioequivalency studies was granted" by the agency. The new policy goes into effect Jan. 1, 1989. One objective of the new policy is to motivate generic manufacturers to demonstrate bioequivalence of their BP products, creating more "AB" equivalent ratings. FDA has been criticized in the past for approving "B" rated products. For example, at a Senate subcommittee hearing chaired by Sen. Metzenbaum (D-Ohio) last year, both PMA and the American Association of Retired Persons recommended that FDA require submission of bioequivalence data, where possible, for products with B ratings ("The Pink Sheet" Oct. 26, 1987, p. 9). PMA testified at the hearing that 1,000 generic drugs, representing nearly 20% of the multisource drugs on the market, have B ratings. ARP suggested the elimination of all B-rated generics where "the state of the art is available" to ensure a product's bioequivalence. The policy will only affect BP rated products when a supplemental ANDA is submitted to the agency. For example, if FDA denies a company's request that the in vivo bioequivalence study requirement be waived, the company has two choices; it can either decide not to move the site of manufacturing or change the formulation or it can conduct the study to show that its product is equivalent to the innovator's. The Orange Book defines BP products as those with "active ingredients and dosage forms with potential bioequivalence problems." Many of the BP products currently listed are for injectable steroid or hormone products, including hydrocortisone acetate, estrogen and testosterone. The Orange Book notes that FDA regs "contain criteria and procedures for determining whether a specific active ingredient in a specific dosage form has a potential for causing a bioequivalence problem. It is FDA's policy to consider an ingredient meeting these criteria as having a potential bioequivalence problem even in the absence of positive data demonstrating inequivalence." Pharmaceutically equivalent products containing these ingredients in oral dosage forms "are included in this category pending resolution of the problem," the Orange Book says. The directory further notes that "injectable suspensions containing an active ingredient suspended in a aqueous or oleaginous vehicle have also been included in this subcategory."