Treatment Patterns for Calcitonin Gene-Related Peptide Monoclonal Antibodies Including Galcanezumab versus Conventional Preventive Treatments for Migraine: A Retrospective US Claims Study

Abstract

Background Most conventional, oral, preventive treatments for migraine are non-specific and ~50% of patients discontinue them within six months. In 2018, the Food and Drug Administration approved three preventive migraine treatments: monoclonal antibodies (mAb) targeting the calcitonin gene-related peptide (CGRP) pathway implicated in migraine; galcanezumab and fremanezumab which target CGRP ligand; and erenumab which targets CGRP receptor. Real-world treatment patterns for CGRP mAb are limited. Purpose To compare real-world treatment patterns for CGRP mAb, specifically galcanezumab versus standard-of-care (SOC) migraine preventive treatments. Patients and methods This retrospective, observational study included 12-month baseline and 6- and 12-month follow-up analyses using IBM ® MarketScan ® databases. Patients identified were aged ≥18 years with ≥1 claim (first claim=index) for CGRP mAb (erenumab, fremanezumab, or galcanezumab) or SOC preventives (eg, antiepileptics, beta-blockers, antidepressants, or onabotulinumtoxinA) as index drugs between May/01/2018 and June/30/2019. Propensity score matching was used to address confounding by observed covariates. Outcomes analyzed included proportion of days covered (PDC), persistence (≤60-day gap), and first non-index drug switch. Descriptive, chi-square (categorical), and t -test (continuous) analyses were conducted. Results The study included 3082 (CGRP mAb versus SOC) and 421 (galcanezumab versus SOC) matched patient pairs with 12-month follow-up. Mean age across cohorts ranged 43.2–44.4 years (females: 85.7–88.6%). Compared with SOC, the CGRP mAb cohort had higher mean persistence (212.5 vs 131.9 days), adherence (PDC: 55.1% vs 35.2%), and more patients were adherent with PDC ≥80% (32.7% vs 18.7%) (all p <0.001). During 12-month follow-up, fewer patients discontinued CGRP mAb versus SOC (58.8% vs 77.6%, p <0.001). Galcanezumab versus SOC comparisons yielded similar results. In the CGRP mAb cohort, most switchers (28.3%) used galcanezumab as subsequent treatment. Largely similar results were observed for 6-month follow-up cohorts. Conclusion Patients on CGRP mAb and specifically galcanezumab showed higher adherence and persistence than patients on SOC migraine preventive treatments.

Monoclonal Antibodies Against Calcitonin Gene-related Peptide for Migraine Prophylaxis: A Systematic Review of Real-world Data

“…The mean time until other ongoing preventive medications were stopped was 185 to 230 days and 36 % had stopped other prophylactics at twelve months, was observed in the third study [35]. In the study including three antibodies [39], patients received significantly less often other prophylactics during follow-up and 75 % stopped other prophylactics during the twelve months follow-up.…”

“…Three studies examined the adherence or persistence. [34,35,39] The adherence to anti-CGRP-mAbs was higher ( 0.8), than to oral prophylactics; but still not at optimum [35]. In the Novartis Go Program [34] offering advice, injection training and Erenumab free of charge until the individual insurance was willing/able to pay for Erenumab, the persistence of treatment was 71 % at 360 days and 63 % at 450 days which is better than under oral preventives [1].…”

“…An exact breakdown of the search results can be seen in Figure 1. We classified these articles into pharmacoepidemiologic studies (n=8) [32][33][34][35][36][37][38][39], clinicbased studies (n=63) , case reports (n=30) and other articles (n=3) [133][134][135]. Seventy-three articles were retrospective and 31 prospective .…”

“…Four studies assessed the prescription of prophylactic medications before and after the first administration of an anti-CGRP-mAb. Three studies reported on Erenumab [32,33,35] and one included Erenumab, Fremanezumab and Galcanezumab [39]. In the first, the prescription of other prophylactics decreased by roughly 30 %.…”

“…In the Novartis Go Program [34] offering advice, injection training and Erenumab free of charge until the individual insurance was willing/able to pay for Erenumab, the persistence of treatment was 71 % at 360 days and 63 % at 450 days which is better than under oral preventives [1]. Varnado et al [39] found a higher main persistence under anti-CGRP-mAbs, than under standard prophylactics, and a significantly higher adherence at six and 12 months (medication possession rate 58 % vs. 37 %, proportion of days covered 55 % vs. 35 %).…”