The subcutaneous route of administration can present challenges to implementing this therapy. In the CALGB studies 8921 and 9221, approximately 23% of patients had significant injection site pain. Moreover, 35 % of patients had injection site bruising which can be extensive in thrombocytopenic patients. Due to limitations on drug concentration and administration volumes for subcutaneous dosing, patients often need to have two or three injections at separate sites each day to meet target dosing. In addition, the schedule of administration is inconvenient in an outpatient setting secondary to the need to schedule administrations over weekends. Therefore, there is great interest in pursuing an abbreviated intravenous route for administration of the drug.