EmstoPA is a first in class antibody-based reversal agent to treat bleeding caused by tissue plasminogen activator (tPA - Activase®, Alteplase®). tPA is a “clot buster” used to remove the blood clots that cause stroke, pulmonary embolism, and myocardial infarction. In the developed world, tPA is most frequently used to treat acute ischemic stroke where the rates of subsequent intracranial hemorrhage (ICH) are 5-7% . EmstoPA belongs to a class of drugs called anti-fibrinolytics, and and the current market for antifibrinolytics is estimated to be $1,100m /year. Currently no specific tPA reversal agents are in development.