Garadacimab for the prevention of hereditary angioedema attacks: a plain language summary of the VANGUARD study

What is this summary about?: This summarizes an article about the clinical study ‘VANGUARD’ that was published in The Lancet journal in February 2023. Hereditary angioedema (HAE) is a rare genetic disease that causes swellings throughout the body (called HAE attacks). HAE attacks in the upper airways (including the tongue and vocal cords) can be life threatening by making breathing difficult. HAE attacks may occur frequently and without warning, and people with HAE have a lower quality of life than other people. In the VANGUARD study, researchers tested the safety of a new medicine called garadacimab and whether it could prevent HAE attacks. Garadacimab was injected subcutaneously (just under the skin) with a needle once a month. What were the results?: In the VANGUARD study, patients took garadacimab or placebo (an identical-looking dummy substance with no medical effect, used for comparison). The aim was to see if garadacimab could prevent HAE attacks better than placebo. Patients taking garadacimab had very few or no HAE attacks, but those taking placebo carried on having attacks. Garadacimab gave protection from HAE attacks shortly after it was first used, and this carried on for the 6 months of treatment. Most patients taking garadacimab (62%) had no HAE attacks throughout the 6 months of treatment (were attack free), but 100% of patients taking placebo had HAE attacks throughout the study. More patients taking garadacimab (82%) than placebo (33%) had a ‘good’ or ‘excellent’ experience living with HAE. Patients taking garadacimab and placebo had similar rates of side effects. Only 5% (2 out of 39) of patients taking garadacimab had discomfort or skin changes at the place of injection compared with 12% (3 out of 25) taking placebo. What do the results mean?: Taking garadacimab once a month helps prevent HAE attacks from happening, with most patients being attack free throughout the 6 months of treatment. Garadacimab had very few and mostly mild or moderate side effects. Overall, garadacimab is a beneficial treatment for preventing HAE attacks.