The purpose of this study is to evaluate the effect of age on PK, safety and tolerability of IV rivipansel.

Inclusion Criteria:

• Healthy female subjects of non-childbearing potential or healthy male subjects who are between the ages of 18-45 years or 65 years of age or older.
• Body mass index (BMI) of 17.5 to 40 kg/m2

Exclusion Criteria:

• Evidence or history of clinically significant hematological, renal, endocrine, pulmonary, gastrointestinal, cardiovascular, hepatic, psychiatric, neurologic, or allergic disease (including drug allergies, but excluding untreated, asymptomatic, seasonal allergies at the time of dosing).
• Pregnant females; breastfeeding female subjects; male subjects with partners currently pregnant
• Treatment with another investigational drug within 30 days or 5 half-lives preceding the dose of study medication
• Blood donation within 60 days prior to dosing.