Education Can Prevent Mix-ups Between Adult, Pediatric Biktarvy Products

The Institute for Safe Medication Practices (ISMP) has received multiple reports about adult patients prescribed and dispensed the pediatric-strength version of bictegravir/emtricitabine/tenofovir alafenamide (Biktarvy) instead of the adult-strength version, resulting in underdosing.

In one case, an adult patient who recently received a diagnosis of HIV was discharged from a hospital with a new prescription for Biktarvy 30 mg/120 mg/15 mg tablets once daily. This dose is appropriate for children who weigh between 14 and 25 kg. The community pharmacist did not recognize that this was an underdose and dispensed the medication to the patient. The patient’s partner, who was prescribed Biktarvy from an HIV clinic, told the patient that the label on the bottle looked different, so the individual contacted the HIV clinic. It was then discovered that the prescriber had ordered the pediatric formulation in error.

The Biktarvy 30 mg/120 mg/15 mg container label does not state that it is a pediatric formulation or indicate the intended weight range (Image). It is unknown whether the hospital or retail pharmacy had a dose range checking alert set up in its computer system to confirm the correct dose. The practitioners involved in prescribing and dispensing this medication did not specialize in HIV care, which could have contributed to the error.

The Biktarvy 30 mg/120 mg/15 mg label (below, left) does not indicate that it is intended for children who weigh between 14 and 25 kg, and the Biktarvy 50 mg/200 mg/25 mg label (below, right) does not indicate that it is intended for adults and children who weigh 25 kg or more.

In a second report, a patient with HIV who had been stable on the correct adult dose of Biktarvy was prescribed and dispensed the pediatric dose of Biktarvy for multiple months following a hospitalization. Once the error was discovered, laboratory testing was done. The patient’s viral load was detectable, which was attributed to the prolonged underdosing with the pediatric strength. Additionally, it was noted that the organizations involved in the error did not specialize in HIV management.

HIV medications are typically considered specialty medications because of their advanced patient management requirements, the critical nature of the treatment, and high costs. In most of the events submitted to the ISMP in which the pediatric strength was dispensed instead of the adult dose, reports indicated that non–infectious disease providers, non–HIV specialists, and pharmacies that do not specialize in HIV were involved in the errors. Inexperienced and untrained prescribers and/or pharmacists may not be aware of the different formulations or dosing cutoffs. Thus, a lack of experience with this medication may have contributed to the errors.

In October 2021, Biktarvy was the first combination, single-tablet dosage form for HIV to be approved in a pediatric-specific formulation. Until the approval of the Biktarvy pediatric formulation, single-tablet antiretroviral therapy (ART) formulations had been associated with 1 established adult dose for each component. Thus, emphasis may not have been placed on memorizing doses in ambulatory and community settings but instead, on ensuring accurate identification of the appropriate brand vs generic names. Also, single-tablet ART formulations may contribute to confusion because of the multiple agents included in a formulation and the look- and soundalike nature of various drug components.

Safe Practice Recommendations

To prevent this type of error, educate prescribers, nurses, and pharmacy staff members who may handle HIV medications on the variouscombination therapies and dosing regimens. Create weight-based order sentences with dose range checking in electronic health records (EHRs) to guide prescribers to select the correct dose. Pharmacy computer systems should alert and prevent entry of the pediatric formulation for adult patients using patient information, such as age and/or weight. Organizations that serve only adult patients should consider removing the pediatric dose from the preferred drug list. One suggestion is to add “pediatric dose” to the drug name for the Biktarvy pediatric product in order entry systems.

The ISMP has contacted Gilead Sciences, Inc, Biktarvy’s manufacturer, and recommended that it better differentiate adult and pediatric container labels. This includes investigating the possibility of indicating on the container label the target population for both adult and pediatric products. The ISMP has also contacted drug information vendors to ask them to explore ways to better differentiate the products in their content, including the content embedded in EHR and pharmacy order entry systems. In addition, the ISMP has asked them to investigate the inclusion of safety messaging about this situation in their referential content.

About the Author

Michael J. Gaunt, PharmD, is a senior director of error reporting programs and editor at the Institute for Safe Medication Practices (ISMP) in Horsham, Pennsylvania. He also serves as the editor of the monthly ISMP Medication Safety Alert! Community/AmbulatoryCare newsletter.