Conference Coverage
Targeting PCSK9 inhibitors to reap most benefit
ANAHEIM, CALIF. – New FOURIER analyses show where evolocumab packs greatest payoff.
MUNICH – Patients with hypercholesterolemia, atherosclerotic cardiovascular disease, and metabolic syndrome received a bigger benefit from treatment with a PCSK9 inhibitor than did otherwise similar patients without metabolic syndrome in a post hoc analysis of data collected from a placebo-controlled trial of a PCSK9 inhibitor with more than 27,000 total participants.
The analysis showed that patients with metabolic syndrome (MetS) treated with the proprotein convertase subtilisin–kexin type 9 (PCSK9) inhibitor evolocumab in the FOURIER study had a statistically significant 17% relative risk reduction in the study’s primary efficacy endpoint compared with placebo, while those without MetS had an 11% relative risk reduction that did not reach statistical significance, Prakash Deedwania, MD, said at the annual congress of the European Society of Cardiology. “Given their higher baseline risk [for cardiovascular disease events], patients with metabolic syndrome had a larger absolute reduction in cardiovascular events,” said Dr. Deedwania, a professor of medicine at the University of California, San Francisco.
For the study’s secondary endpoint of the combined rate of cardiovascular disease death, nonfatal MI, and nonfatal stroke, patients with MetS treated with evolocumab had a statistically significant 24% relative risk reduction compared with placebo, while those without MetS had an insignificant 14% reduction. Dr. Deedwania and his associates calculated these relative risk reductions and those for the primary endpoint using adjustments for baseline differences between the MetS and non-MetS subgroups in age, race, sex, history of diabetes, history of MI, heart failure, smoking, renal function, LDL cholesterol levels, and use of a high-intensity dosage of a statin. Among the 27,342 patients enrolled in the trial 16,361 (60%) had MetS at entry into the study, which made this “the largest study ever reported for patients with metabolic syndrome,” he noted.
“Evolocumab was still effective in patients without metabolic syndrome, but it was of lesser magnitude, and that combined with the fewer patients in the non–metabolic syndrome subgroup meant the effect did not reach statistical significance,” Dr. Deedwania explained. “These data help identify the patients who benefit the most from treatment with an expensive drug,” a PCSK9 inhibitor. Based on list prices the annual cost for treatment with a PCSK9 inhibitor such as evolocumab (Repatha) or a second approved drug from this class, alirocumab (Praluent), is roughly $14,000 (JAMA Cardiol. 2017 Oct;2[10]:1066-8).
The analysis run by Dr. Deedwania used data collected in the FOURIER (Further Cardiovascular Outcomes Research With PCSK9 Inhibition in Subjects With Elevated Risk) trial, which had showed an overall relative risk reduction of 15% compared with placebo during a median follow-up of 2.2 years for the primary endpoint of cardiovascular death, nonfatal MI, nonfatal stroke, hospitalization for unstable angina, or coronary revascularization (N Engl J Med. 2017 May 4;376[18]:1713-22). The study ran at 1,242 sites in 49 countries. He and his associates identified enrolled patients with MetS using the definition of the 2001 Third Report from the National Cholesterol Education Program: People with at least three of five criteria – fasting blood glucose of at least 100 mg/dL; waist circumference greater than 102 cm in men and 88 cm in women; systolic blood pressure of at least 135 mm Hg, diastolic blood pressure of at least 85 mm Hg, or a history of hypertension diagnosis; a triglyceride level greater than 150 mg/dL; and an HDL cholesterol level of less than 40 mg/dL in men and less than 50 mg/dL in women (JAMA. 2001 May 16;285[19]:2486-97).
The new analysis also showed that treatment with evolocumab led to an incremental, average reduction in LDL cholesterol of 58% in patients with MetS and 61% in patients without MetS at the time of enrollment. The patients with MetS in FOURIER overall had a significantly higher number of primary endpoint events, 15.8%, than enrolled patients without MetS, 12.9%, regardless of whether or not they received evolocumab, a relative risk of 21% more events after adjustment. The analysis also showed that treatment with evolocumab was equally safe and well tolerated by patients regardless of whether or not they had MetS, and that patients with MetS had no increased incidence of diabetes or elevations in fasting blood glucose or hemoglobin A1c while on treatment compared with those without MetS.
Dr. Deedwania has been a consultant to Amgen, the company that markets evolocumab, and to Sanofi, the company that markets a different PCSK9 inhibitor, alirocumab.