BIOEQUIVALENCE SAMPLES MUST BE RETAINED FOR AT LEAST FIVE YEARS

BIOEQUIVALENCE SAMPLES MUST BE RETAINED FOR AT LEAST FIVE YEARS after approval of original and supplemental ANDAs or NDAs, effective Nov. 7, under an interim rule FDA published the same day in the Federal Register. The agency will accept comments on the rule until Jan. 7, 1991 and is specifically interested in comments on whether five years is an appropriate length for the retention period. "The reserve samples will be required to be retained for a period of at least five years following the date on which a full or abbreviated new drug application or supplemental application is approved" the rule states. The same requirement applies "if such an application or supplemental application is not approved, at least five years following the date of completion of a bioavailability of bioequivalence study." FDA described the rule as an outgrowth of a February 1988 agency task force report that recommended improving procedures to detect and evaluate reports of therapeutic failures that could be tied to product inequivalence. Less than two weeks before the rule's publication, bioequivalence samples submitted in support of Bolar's ANDA for a generic version of SmithKline's Dyazide were confirmed to be in fact the innovator product ("The Pink Sheet" Oct. 29, p. 24). Under the rule, "the applicant or contract testing facility will retain a sufficient quantity of each reserve sample to permit FDA to perform five times all of the release tests required in the application or supplemental application." The sample must be adequately identified "so that the reserve sample can be positively identified as having come from the same sample as used in the specific bioavailability or bioequivalence study," the notice states. FDA investigators generally will collect test samples during a preapproval inspection of the manufacturer's facilities and of the contract research laboratories, which also will allow FDA investigators to inspect storage conditions. "To further deter fraudulent practices in bioavailability and bioequivalence testing, the agency intends to randomly sample reserve samples," the rule advises. Noting that "resource considerations may impose limits on the number of samples that the agency can collect and test," the agency directs that firms must retain samples for five years even if samples have not been collected or requested. In considering whether additional requirements are necessary "to ensure that the integrity of the reserve samples is not compromised during the retention period," the agency is soliciting comments on the following questions: "(1) Should the reserve samples be required to be stored in an area where access is controlled and that is separate from the testing area; (2) Should the testing facility be required to appoint a sample custodian who is responsible for proper storage of the reserve samples and release for analysis when requested by FDA; and (3) How should the reserve samples be packaged during the retention period to ensure that samples' integrity is not compromised? For example, should the package be required to be sealed in some manner to prevent tampering?" The regulation applies to foreign contract facilities and foreign applicants as well as domestic firms. Failure to comply with the rule could render a pending application unapprovable or lead to the withdrawal of approval for an already marketed drug, the agency advised.