Rates of PCSK9 Inhibitor Initiation in ASCVD Patients Still Lagging Behind

Peter Groeneveld, MD, MS

Despite efforts to improve affordability of the class, new research suggests the cost of PCSK9 inhibitors may still be preventing optimal uptake of prescribing among patients with atherosclerotic cardiovascular disease (ASCVD).

A retrospective look at nationwide claims data from 2015-2019, results indicate the number of patients with ASCVD who began treatment with PCSK9 inhibitors remained subpar despite guideline recommendations and a mounting evidence base supporting use.

“Among various patient subgroups identified as potentially greatly benefiting from PCSK9 inhibitors, we still found less than 1% were started on PCSK9 inhibitor therapy. Thus, the magnitude of price reductions may not yet be sufficient to influence use management strategies aimed to limit PCSK9 inhibitor use,” wrote investigators.

With the approvals of evolocumab and alirocumab in 2015, a novel class of medications was added to the armamentarium of lipidologists and cardiologists. However, the adoption of PCSK9 inhibitors has been hampered by cost of the medications. With clinical trial data supporting use continuing to grow and recent guidelines including recommendations for PCSK9 inhibitors, major initiatives have been launched aimed at reducing cost and improving patient access.

To learn more about trends in prescribing among patients with ASCVD, a Penn Medicine-led team designed a retrospective cohort study using data from the Optum Clinformatics Data Mart database. The main goal of the investigators’ analyses was to identify the number of patients with ASCVD who filled a first prescription for a PCSK9 inhibitor during the study period and investigators also hoped to compare proportion of patients with ASCVD who filled a first prescription for a PCSK9 inhibitor with patients with ASCVD who were filling statin prescriptions.

Searching for patients aged 18-64 years who filled a prescription for a PCSK9 inhibitor or a statin from January 1, 2015, through June 30, 2019, investigators identified more than 125,000 patients for inclusion in their final analyses. Their initial search yielded data related to 1,696,007 patients on station therapy and 3463 one a PCSK9 inhibitor. After exclusion of those with missing data and restricting the cohort to patients with ASCVD, a final study cohort of 126,419 patients was identified for inclusion. Of note, patients included in the study needed to have at least 12 months of continuous insurance enrollment prior to index prescription.

Among the 126,419 patients included, just 1168 (0.9%) filled a prescription for a PCSK9 inhibitor during the study period. Additionally, multiple subgroups analyses were performed and found similar or lower rates of PCSK9 inhibitor use compared to the overall study cohort.

Among 54,815 patients on a high-intensity statin, 478 (0.9%) were initiated on a PCSK9 inhibitor. Among 27,122 who were highly adherent to a high-intensity statin, 143 (0.5%) were initiated one a PCSK9 inhibitor. Lastly, among 13,643 patients with high adherence and an LDL-C above 70 mg/dL, 119 (0.9%) were initiated on a PCSK9 inhibitor.

When assessing factors associated with PCSK9 inhibitor initiation, multivariable analyses revealed multiple disparities based on gender, location of residence, and income. Compared to their male counterparts, women had greater odds of initiating therapy with a PCSK9 inhibitor than men and patients in the Midwest were had lower odds of initiating therapy (OR, 0.73; 95% CI, 0.53-0.99; P=.04) than those living in the Northeast. Compared to those with annual household income less than $50,000, those with an annual household income between $50,000-$99,999 (OR, 1.31; 95% CI, 1.05-1.65; P=.002) or more than $99,999 (OR, 2.06; 95% CI, 1.66-2.55; P <.001) also had greater odds of initiating therapy.

“The potential clinical benefits of novel therapies, such as PCSK9 inhibitors, may not be realized if barriers to access remain,” noted investigators in their conclusion.

This study, “Adoption of PCSK9 Inhibitors Among Patients With Atherosclerotic Disease,” was published in the Journal of the American Heart Association.