Confusion over US name and International Nonproprietary Name
A clinical pharmacist reported confusion when pharmacy staff initially tried to locate ANDEXXA (coagulation factor Xa [recombinant], inactivated-zhzo), manufactured by Alexion Pharmaceuticals for Astra-Zeneca. This product is a reversal agent for patients taking ELIQUIS (apixaban) or XARELTO (rivaroxaban) who are experiencing life-threatening or uncontrolled bleeding. Andexxa is also used off-label to reverse anticoagulation with SAVAYSA (edoxaban) and LOVENOX (enoxaparin).
Andexxa has an International Nonproprietary Name (INN), andexanet alfa, which is widely cited in professional references including Lexicomp, but not included on the vial label or product labeling. In one case, a clinical pharmacist called the main pharmacy to confirm the availability of andexanet alfa in anticipation of a patient who was potentially at high risk of bleeding. After searching the pharmacy inventory, a pharmacy technician reported that the pharmacy did not have the medication. However, the pharmacy procurement staff notified the clinical pharmacist the following morning that the pharmacy had 35 vials on hand. The next month, a hematologist contacted the same clinical pharmacist to ensure the pharmacy had andexanet alfa on hand in case it was needed if protamine failed to reverse active bleeding for a patient who had a supratherapeutic dose of enoxaparin. The clinical pharmacist requested andexanet alfa and a pharmacy technician informed him the pharmacy did not have the drug. Remembering he had been told that the pharmacy had 35 vials of Andexxa on hand, the clinical pharmacist followed up with the sterile compounding supervisor, who mentioned that the nonproprietary name on the actual container label is coagulation factor Xa (recombinant), inactivated zhzo (see Andexxa). With this information, the pharmacy technician was then able to locate the medication.
The confusion caused by the various nonproprietary naming conventions could lead to treatment delays or lack of access to the needed reversal agent. Per the US FDA Center for Biologics Evaluation and Research, the US nonproprietary naming convention uses the blood factor name rather than the INN. Organizations should review how this medication is prescribed and displayed in their electronic health record and ensure consistent naming across all systems, labels, and storage areas. Including the brand name with the generic name in search fields and order sets may help reduce confusion. Alert staff to the INN and US naming convention differences to ensure the medication can be located when needed. If unfamiliar with the medication's blood factor name, consider affixing a temporary auxiliary label to notify staff that this product is also known as andexanet alfa.
Lot number or expiration date?
A case was reported to the ISMP wherein a vial of droperidol (5 mg/2 mL, American Regent) appeared to have expired on January 24, 2020 (see Droperidol vial). Droperidol Injection is indicated to reduce the incidence of nausea and vomiting associated with surgical and diagnostic procedures. However, 2020 is actually the lot number, as noted by the small words printed just below the bar code. Thus, the last day of January 2024 is the actual expiration date. Displaying a 4-digit lot number that is similar to a recent year, and listing it right next to the expiration date, contributes to confusion. This could lead to unnecessarily discarding what is thought to be an expired medication, a situation made worse by the medication having been on the drug shortage list.
If the lot number needs to be numerical, manufacturers should consider using at least 5 numbers and incorporating letters at the beginning and/or end of the lot number to differentiate it from the expiration date. USP General Chapter <7> on Labeling will be requiring manufacturers to use a 4-digit year on their products by 2023. In May 2022, the US FDA released a labeling guidance document, Safety Considerations for Container Labels and Carton Labeling Design to Minimize Medication Errors (http://www.ismp.org/ext/930), which also includes a 4-digit recommendation for the expiration date year.