Effect of intensive LDL cholesterol lowering with PCSK9 monoclonal antibodies on tendon xanthoma regression in familial hypercholesterolemia.

BACKGROUND AND AIMS: The effect of LDLc lowering with PCSK9 antibodies on tendon xanthomas (TX) is unknown.

METHODS: TX was measured in 24 heterozygous familial hypercholesterolemia (HeFH) cases and in 24 HeFH controls with or without PCSK9 inhibitors for at least one year.

RESULTS: Exposure to PCSK9 inhibitors in cases was 2.96 ± 1.33 years. LDLc decreased 80.8 ± 7.66% in cases and 56.9 ± 11.1% in controls. There was a decrease in maximum (-5.03%) and mean (-5.32%) TX in cases but not in controls (+3.97%, +3.16, respectively, p = 0.01). PCSK9 inhibitor treatment was independently associated with TX reduction.

CONCLUSION: Addition of a PCSK9 inhibitor to statin and ezetimibe resulted in a greater decrease in LDLc and TX after 3 years of treatment.