10.4 Biosimilars/Biologics, Pharmacy-to-Pharmacy Transfers & Foreign Sourcing

This section covers three topics the exam treats as a group: the biologic/biosimilar regulatory framework, physical pharmacy-to-pharmacy drug transfers under DSCSA, and foreign sourcing of drugs. Each appears in Domain 3 as an alternative-supply or alternative-product path, and each is defined by a specific federal rule.

Biologics, Biosimilars, and Interchangeable Biosimilars

A biologic is a product derived from a living organism — monoclonal antibodies, vaccines, blood products, gene therapies. Biologics are approved by FDA under a Biologics License Application (BLA), not under an NDA or ANDA. The holder of the original BLA is the reference product.

A biosimilar is a biologic that is highly similar to the reference product, with no clinically meaningful differences in safety, purity, or potency. Biosimilars are approved under a biosimilar pathway (the 351(k) pathway under the Public Health Service Act), not under an ANDA. The key idea: a biosimilar is shown to be highly similar, but it is not assumed to be identical — biologics are large, complex molecules that cannot be exactly copied.

An interchangeable biosimilar is a biosimilar that has met additional FDA requirements such that it may be substituted for the reference product at the pharmacy level without the prescriber's intervention, subject to state law. FDA's designation of interchangeability is what permits pharmacy-level substitution; whether substitution actually happens depends on each state's pharmacy practice act.

Biosimilars Are Not Generics

The exam often tests this distinction:

Biosimilars increase competition in the biologic market and may lower cost, but they are not generics and do not follow the ANDA pathway.

Pharmacy-to-Pharmacy Transfers Under DSCSA

The exam draws a sharp line between two kinds of "transfer":

• Transfer of a patient prescription — moving the Rx (the paper or electronic authorization to dispense) from one pharmacy to another so a different pharmacy can dispense. That is a prescription transfer, governed by state pharmacy law, not DSCSA.
• Physical transfer of a drug — moving the actual drug product (inventory) between two pharmacies. That is a supply-chain transaction and does fall under DSCSA.

The official outline specifies: "Types of and requirements for drug transfers between pharmacies (physical transfer of the prescription drug, not transfer of a patient prescription)."

DSCSA conditions for a physical drug transfer include passing T3 data (transaction information, transaction history, transaction statement) when the transfer is between trading partners, and the receiving pharmacy must verify product identifiers when required under EDDS (Enhanced Drug Distribution Security), whose compliance dates phased in from May 27, 2025 for manufacturers and repackagers through November 27, 2026 for small dispensers.

Intracompany Transfers

An intracompany transfer — a physical transfer of a drug between two pharmacies or facilities within the same corporate entity (e.g. between two stores of the same chain, or between a chain's central fill and a retail store) — is treated differently from a transfer between unrelated trading partners. DSCSA excludes two such movements from the definition of a transaction outright: intracompany distribution of a product between members of an affiliate or within a manufacturer, and distribution of a product among hospitals or other health care entities that are under common control. Because neither is a transaction, no transaction information or transaction statement has to flow with it. The key exam point: common ownership or common control is what converts a physical transfer into a non-transaction.

The Governing Standard: "Specific Patient Need"

DSCSA defines the term precisely. Specific patient need means the transfer of a product from one pharmacy to another to fill a prescription for an identified patient. The statute then closes the loophole in the same sentence: the term does not include the transfer of a product from one pharmacy to another to increase or replenish stock in anticipation of a potential need.

That single definition is the whole test, and it is exactly the kind of distinction the exam draws:

Where the "5%" Figure Actually Comes From

Candidates often bring a half-remembered "5% rule" to this topic. Be careful with it. The 5% figure in federal law attaches to the exclusion for distribution of minimal quantities of product by a licensed retail pharmacy to a licensed practitioner for office use — FDA has proposed defining "minimal quantities" as no more than 5 percent of the pharmacy's total annual prescription drug sales. It is not a general allowance to move 5% of your inventory to other pharmacies. Several state pharmacy laws do contain their own 5% wholesale-licensure thresholds, which is where the confusion originates; DSCSA itself governs pharmacy-to-pharmacy transfers through the specific patient need standard, not a percentage.

Foreign Sourcing and Section 804

Foreign sourcing of drugs is tightly restricted. The general rule is that a drug manufactured outside the United States and imported for commercial sale in the U.S. must come through FDA-approved pathways:

• Foreign establishment registration — a foreign manufacturer that ships drug product to the U.S. must register with FDA and must designate a U.S. agent as a point of contact for FDA communications
• Section 804 importation programs — the FDA may approve state or tribal importation programs under Section 804 of the FDCA that allow certain prescription drugs to be imported from Canada (or other eligible countries under specific FDA pathways) under tightly controlled conditions, with testing, labeling, and FDA oversight. These programs are path-specific; they are not blanket permission.
• Personal importation — individual personal importation of small quantities of a drug that is not FDA-approved is generally restricted and is permitted only in narrow, FDA-discretionary circumstances (e.g. a serious condition with no U.S. alternative). It is not a commercial supply-chain path.

For the exam, the core points are: foreign establishments must register with FDA and have a U.S. agent; Section 804 allows specific, FDA-approved state/tribal importation programs with strict controls; individual personal importation is not a commercial channel.

In Practice

A hospital system that wants to move 50 vials of a scarce oncology drug from its cancer-center pharmacy to its affiliate clinic pharmacy is doing a physical drug transfer. If the two sites are under common control, the movement is excluded from the definition of a transaction and no transaction data has to flow. If they are separately owned, the transfer is a transaction: it is permitted without wholesale-distributor licensure only if it meets the specific patient need standard, and full transaction data and product-identifier verification under DSCSA apply. The pharmacy is not "importing" the drug — it is moving domestic inventory between two points in the supply chain. A separate hospital that wants to source a cheaper version of a biologic should look for a biosimilar or, if available and state law allows, an interchangeable biosimilar that can be substituted at the pharmacy level; it is not using a generic, because biologics have no ANDA pathway.