Background: Since the FDA approval of proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i), alirocumab and evolocumab, in 2015, initial and ongoing use has been low. The reasons for this have not been well described.
Methods: A web-based survey was conducted of adults who signed up for a pharmaceutical company-sponsored patient support program after prescription for a PCSK9i.
Results: Overall, 798 of 4,525 participants (17.6%) completed the survey from 50 states - 54.0% male, 91.8% Caucasian. Among those prescribed PCSK9i, 75.0% were prescribed by a cardiologist. Of these, 699 (87.6%) initially started PCSK9 therapy. Of those initiating therapy, 80.7% received free medications (e.g. samples) at some point while only 484 (66.8%) received approval for insurance coverage. While nearly all (99.6%) starting PCSK9 therapy had tried a statin, few reported being on a statin (31.1%), a high-intensity statin (16.7%), or ezetimibe (18.8%) when they were prescribed PCSK9i. Likelihood for receiving insurance approval for PCSK9i was slightly higher among those reporting prior atherosclerotic cardiovascular disease (ASCVD) or familial hypercholesterolemia (FH) (70.2% vs 60.6%, p=0.009 for ASCVD, 71.1% vs. 63.1% p=0.02 for FH) but did not differ by statin use (66.3% yes vs 67.6% no, p=0.7), high-intensity statin use (66.7% yes vs. 65.8% no p=0.3), or among those who reported their latest LDL-C was >190 mg/dL or not (71.7% vs 64.7%, p=0.07). Among those approved for insurance coverage for PCSK9i therapy, 43% reported no copay while 16.3% paid over $400/month out of pocket. Two thirds of those who ever initiated therapy (67.7%) were still on treatment. Of those who stopped, 9.0% stopped within 1 month, 36.0% in 1-3 months, 15.8% in 4-6 months, 39.2% after 6 months. The leading cause for discontinuation was high out of pocket costs (25.2%) and a failure to receive insurance approval or reapproval (30.5%).
Conclusion: Up to a third starting PSCK9i medication discontinue therapy, driven by high out-of-pocket costs and lack of insurance approval. Approval success did not correlate with LDL levels or current statin use.