Utilization of PCSK-9 Inhibitors in Statin Intolerant Cardiac Transplant Patients

Abstract

Background HMG CoA Reductase Inhibitors, commonly referred to as statins, are widely used in heart transplant patients as dyslipidemia is common after cardiac transplantation and increases the risk of cardiovascular adverse events including cardiac allograft vasculopathy (CAV). However, not all patients can tolerate statins or see an adequate lowering of the low density lipoprotein cholesterol (LDL-C). Proprotein convertase subtilisin/kexin type 9 (PCSK-9) inhibitors have been shown to be effective at lowering LDL with great tolerance and excellent safety profiles in the general population. Yet, there is limited data regarding effect of PCSK9 inhibitors in heart transplant patients. Objective To study the effect of PSCK-9 inhibitors in post-cardiac transplant patients. Method We reviewed post heart transplant patients who received PCSK9 inhibitors at our University Medical Center from 2017 to March 2020. We found four patients who were eligible. Results The mean age of the four patients was 65.75± 4.7 years (3 Females). Indication for PCSK9 inhibitors in three patients was statin intolerance due to myopathy; the fourth patient had familial hypercholesterolemia that required more aggressive therapy. Average time for initiation of the medication since heart transplant was 10.25 years. The average duration of treatment was 18.25 months. Two patients were on Evolocumab 140mg subcutaneously once every 2 weeks, and the other two were on Alirocumab 75mg every 2 weeks. All four patients continued the medicine with no side effects. Mean LDL-C prior to initiation of the drug was 125.75± 24.42 mg/dL. At 8-12 week follow up there was significant reduction in the LDL 35.75 ±13.74mg/dL (p=0.006).There was no significant dose changes to the immunosuppressive medications. None of the four patients experienced rejection of the transplanted heart. Only one patient with familial hypercholesterolemia had mild CAV on heart catheterization prior to initiation of the drug and there was no progression of the CAV at one year follow up. Conclusion PCSK9-inhibitors were effective in reducing low-density lipoprotein levels in post-cardiac transplant patients and were well tolerated without any rejection or modifications to the transplant medications in this small cohort of patients. The study findings are promising and highlight the need for larger, prospective, multicenter studies.