Assistant Professor University of Hong Kong, Hong Kong
Background: Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a protein that regulates cholesterol in humans. PCSK9 inhibitors were approved in Hong Kong in 2016 for lowering high cholesterol, especially for patients who were diagnosed with familial hypercholesterolemia. Less information exists on the prescription pattern of PCSK9 inhibitors in Hong Kong.
Objectives: The study aims to describe the prescription trend of PCSK9 inhibitors and the characteristics of PCSK9 inhibitors users in Hong Kong.
Methods: We described the prescribing trend using the electronic health records retrieved from the database of Hospital Authority in Hong Kong. De-identified data including all medication use information was extracted. This study included patients with PCSK9 inhibitors prescription from August 2016 to December 2020. We described the yearly and quarterly number of PCSK9 inhibitor prescriptions filled and the trend during the study period. We also calculated the quarterly number of dispensed defined daily doses (DDD) of PCSK9 inhibitors. All analyses were conducted in all PCSK9 inhibitors and two types of injections (Evolocumab or Alirocumab) respectively. Demographic characteristics of PCSK9 users were also examined.
Results: Within the study period, 1480 PCSK9 inhibitor prescriptions were filled (Evolocumab: 62.77%, Alirocumab: 37.23%), with an increasing prescription trend. Yearly prescriptions increased from 15 in 2016 to 614 in 2020. The total dispensed quantity of PCSK9 inhibitors also reflects the increase for both Evolocumab (84 to 17990 DDDs) and Alirocumab (167 to 7931 DDDs). We identified a total of 287 new users of PCSK9 inhibitors, 71.43% of them were male, and their age at first prescription ranged from 35 to 90. The quarterly individuals prescribed PCSK9 inhibitors ranged from 2 to 116. The maximum prescription fill for new users was 1260 DDDs. Most of the users also received other lipid-lowering drugs, with only 1% prescribed PCSK9 inhibitors only.
Conclusions: PCSK9 inhibitors prescriptions have been increasing since approval in Hong Kong. With the increasing trend, estimating the safety and effectiveness of PCSK9 inhibitors in the real-world setting is needed.
