6 ADVERSE REACTIONS The most common adverse reactions in AIMOVIG clinical studies (occurring in at least 3% of treated patients and more often than placebo) are injection site reactions and constipation (6.1) To report SUSPECTED ADVERSE REACTIONS, contact Amgen Medical Information at 1-800-77-AMGEN (1-800-772-6436) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. The safety of AIMOVIG has been evaluated in 2,537 patients with migraine who received at least one dose of AIMOVIG, representing 2,310 patient-years of exposure. Of these, 2,057 patients were exposed to 70 mg or 140 mg once monthly for at least 6 months, 1,198 patients were exposed for at least 12 months, and 287 patients were exposed for at least 18 months. In placebo-controlled clinical studies (Studies 1, 2, and 3) of 2,184 patients, 787 patients received at least one dose of AIMOVIG 70 mg once monthly, 507 patients received at least one dose of AIMOVIG 140 mg once monthly, and 890 patients received placebo during 3 months or 6 months of double-blind treatment [see Clinical Studies ( 14 )]. Approximately 84% were female, 91% were white, and the mean age was 42 years at study entry. The most common adverse reactions (incidence ≥ 3% and more often than placebo) in the migraine studies were injection site reactions and constipation. Table 1 summarizes the adverse reactions that occurred during the first 3 months in the migraine studies (Studies 1, 2, and 3). Table 1: Adverse Reactions Occurring with an Incidence of at Least 2% for Either Dose of AIMOVIG and at Least 2% Greater than Placebo During the First 3 Months in Studies 1, 2, and 3 Adverse Reaction AIMOVIG 70 mg Once Monthly N = 787 % AIMOVIG 140 mg Once Monthly N = 507 % Placebo N = 890 % Injection site reactionsa 6 5 3 Constipation 1 3 1 Cramps, muscle spasms < 1 2 < 1 aInjection site reactions include multiple adverse reactions related terms, such as injection site pain and injection site erythema. In Studies 1, 2, and 3, 1.3% of patients treated with AIMOVIG discontinued double-blind treatment because of adverse events. The most frequent injection site reactions were injection site pain, injection site erythema, and injection site pruritus. 6.2 Immunogenicity As with all therapeutic proteins, there is potential for immunogenicity. The detection of antibody formation, including neutralizing antibodies, is highly dependent on the sensitivity and specificity of the assay. Additionally, the observed incidence of antibody (including neutralizing antibody) positivity in an assay may be influenced by several factors including assay methodology, sample handling, timing of sample collection, concomitant medications, and underlying disease. For these reasons, comparison of the incidence of antibodies to erenumab-aooe in the studies described below with the incidence of antibodies in other studies or to other products may be misleading. The immunogenicity of AIMOVIG has been evaluated using an immunoassay for the detection of binding anti-erenumab-aooe antibodies. For patients whose sera tested positive in the screening immunoassay, an in vitro biological assay was performed to detect neutralizing antibodies. In controlled studies with AIMOVIG, the incidence of anti-erenumab-aooe antibody development was 6.2% (48/778) in patients receiving AIMOVIG 70 mg once monthly (2 of whom had in vitro neutralizing activity) and 2.6% (13/504) in patients receiving AIMOVIG 140 mg once monthly (none of whom had in vitro neutralizing activity). The neutralizing anti-erenumab-aooe antibody positive rate may be underestimated because of limitations of the assay. Although these data do not demonstrate an impact of anti-erenumab-aooe antibody development on the efficacy or safety of AIMOVIG in these patients, the available data are too limited to make definitive conclusions.