This is a very reasonable, nicely done, fairly powered observational study showing that, as all of the formulations except high-molecular-weight iron dextran, ferumoxytol is a safe and effective means of supplying iron. What it doesn’t address is the reason there is a perception of increase SAEs with this drug in some corners. In my opinion, that perception is exclusively driven by the ill-considered decision to administer the drug in 17 seconds. When given over one minute it is virtually seamless, which is supported by the recently published, well powered, prospective study by Macdougall et al. recently published in the Clinical Journal of the American Society of Nephrology, which compared ferumoxytol to iron sucrose (Macdougall IC et al, Clin J Am Soc Nephrol 2014 Jan 23 [Epub ahead of print]).