Secondary outcomes, assessed by the change in the number of monthly headache days by at least 25%, 75%, or 100%, were also not significant following treatment with CGRP monoclonal antibodies.
Despite the common occurrence of headaches in patients with idiopathic intracranial hypertension (IIH), new data showed that treatment with a calcitonin gene-related peptide (CGRP) monoclonal antibodies did not yield significant reductions of at least 50% in monthly headache days (MHD) compared with placebo.1
Lead author Lindsay Frerichs, MD, fellow, UT Southwestern Medical Center, and colleagues conducted a retrospective chart review of patients with an established diagnosis of IIH and who were treated from May 2018 to January 2020 with an anti-CGRP monoclonal antibody. At the conclusion of the analysis, no statistical difference was observed in the relative change in MHD, the primary end point, at 3 months (95% CI, –0.05 to 0.44) or 6 months (95% CI, –0.95 to 0.59).
The study, presented at the 2022 American Headache Society (AHS) Annual Meeting, June 9-12, in Denver, Colorado, aimed to understand the role of migraine and its pathophysiology in persistent post-IIH headache. IIH, a rare condition also called pseudotumor cerebri, occurs when there is too much cerebrospinal fluid build-up, essentially putting extra pressure on the brain and optic nerve. Symptoms of the condition include headaches, tinnitus, temporary blindness, double vision, blind spots, neck and shoulder pain, and peripheral vision loss.
In total, 24 of the 79 observed charts were included in the analysis, with most of the cohort women (95.8%; n = 23) and Caucasian (75%; n = 18). At baseline, patients demonstrated mean MHD of 24.39 (SD, 7.35) and Migraine Disability Assessment scores of 88.39 (SD, 63.58) indicating severity. On average, patients tried a total of 5.87 (SD, 2.82) preventive migraine medications, with 62.5% who experienced medication overuse headache.
Galcanezumab (Emgality; Eli Lily), erenumab (Aimovig; Novartis), and fremanezumab (Ajovy; Teva Pharmaceuticals), the only approved GCRP monoclonal antibodies at the time of the analysis, were used by 10 (41.7%), 9 (37.5%), and 4 (16.7%) patients, respectively. In addition to no statistically significant differences on the primary outcome, the secondary end point of change in the number of MHD by at least 25%, 75%, or 100% from baseline was also not met.
There have been few studies specifically evaluating medications that target CGRP pathways to treat headache in IIH. One 2020 analysis included 7 patients in whom headaches were the presenting feature of IIH, with the headaches showing migraine-like characteristics, as in typical in many patients with the condition. These headaches responded markedly to erenumab, although there was a recurrence of raised increased intracranial pressure, as evidenced by a return of the papilledema, which was previously settled before treatment. Notably, the headaches did not recur while on treatment with erenumab, suggesting that CGRP could be a mechanistic driver for headache in patients with active IIH.2