526 Background: Infusion reactions have been reported in studies of metastatic colorectal cancer (mCRC) patients treated with anti-EGFR therapies, including cetuximab and panitumumab, with incidences ranging from 0-33%. A systematic literature review and meta-analysis were conducted to estimate the incidence of infusion reactions in this population and identify variations in this incidence by patient and study characteristics. Methods: Multiple scientific databases were searched to identify observational studies or clinical trials of mCRC patients treated with anti-EGFR therapies that reported rates of infusion reactions, hypersensitivity, or allergy/anaphylaxis. Random effects models were used to meta-analyze the incidence of infusion reactions overall and stratified by therapy, study design, geographic location, KRAS mutation status, and grade of reaction severity. Results: Among 48 studies included in this meta-analysis, the pooled estimate for infusion reaction incidence was 0.049 (95% CI: 0.036 – 0.065), or nearly 5%. Reactions of grades 1 or 2 were more common than reactions of grades 3-5 (0.089 vs. 0.028) No significant variations in infusion reaction incidence were observed by study design, KRAS status, or study location. Conclusions: Infusion reactions occur in approximately 5% of mCRC patients treated with anti-EGFR therapies and the incidence varies significantly by grade and severity. Future studies should consider investigating survival outcomes for only those patients with infusion reactions to determine its prognostic relevance.