Inclusion Criteria Stage I/II/IIb: (COMPLETE AND CLOSED TO ACCRUAL)
- Participants must have sickle cell anemia confirmed by hemoglobin analysis
- Participants must report that their pain is at baseline. Additionally, they cannot report an increase in dose or frequency of opioid use in the last 2 weeks prior to drug administration
- Age 21-70 years
- Participants must have the laboratory indices as outlined in the protocol
- Participants must have reliable IV access as determined by the investigator
- Women of child-bearing potential and men must agree to use adequate contraception prior to study entry and for the duration of the study.
Inclusion Criteria Stage III: (COMPLETE AND CLOSED TO ACCRUAL)
- Participants must have sickle cell anemia confirmed by hemoglobin analysis
- Participant is admitted to the hospital for a pain episode
- Age 21-70 years
- Participants must have the laboratory indices as outlined in the protocol
- Participants must have reliable IV access as determined by the investigator
- Women of child-bearing potential and men must agree to use adequate contraception prior to study entry and for the duration of study participation
Inclusion Criteria Stage IV: (open, still accruing volunteers)
- Participants must have sickle cell disease confirmed by hemoglobin analysis
- Participant is admitted to the hospital for a pain episode
- Ages of assent (10 to 17 years at DFCI, but different depending on institution)
- Participants must have the laboratory indices as outlined in the protocol
- Participants must have reliable IV access as determined by the investigator
- Participants and parents must have the ability to understand and the willingness to sign a written informed consent and assent document
- Women of child-bearing potential and men must agree to use adequate contraception prior to study entry and for the duration of study participation
Exclusion Criteria Stage I/II/IIb: (COMPLETE AND CLOSED TO ACCRUAL)
- Participants with a current physician diagnosis of asthma (within last 12 months), require continuous supplemental oxygen, or predicted or current use of some asthma medications.
- Participants with second- or third-degree AV block or sinus node dysfunction
- Have a history of bleeding diathesis
- Have a history of clinically overt stroke
- Have a history of severe hypertension not adequately controlled with anti-hypertensive medications
- Participants who are receiving chronic anti-coagulation or anti-platelet therapy
- Participants with a history of metastatic cancer
- Participants who have had a hospitalization or emergency room visit for any reason in the past 2 weeks
- Participants may not be receiving any other study agents or have received a study agent in the past 30 days
- Uncontrolled intercurrent illness
- Pregnant or breastfeeding women
- Participants with HIV
- Participants who have previously enrolled and received the investigational agent as part of this study
- Participants who are taking medications that may interact with the investigational agent
Exclusion Criteria Stage III: (COMPLETE AND CLOSED TO ACCRUAL)
- Participants with a current physician diagnosis of asthma (within last 12 months), require continuous supplemental oxygen, or predicted or current use of some asthma medications.
- Participants with second- or third-degree AV block or sinus node dysfunction
- Have a history of bleeding diathesis
- Have a history of clinically overt stroke
- Have a history of severe hypertension not adequately controlled with anti-hypertensive medications
- Participants who are receiving chronic anti-coagulation or anti-platelet therapy
- Participants with a history of metastatic cancer
- Participants may not be receiving any other study agents or have received a study agent in the past 30 days
Exclusion Criteria Stage IV: (open, still accruing volunteers)
- Participants with a current physician diagnosis of asthma (within last 12 months), require continuous supplemental oxygen, or predicted or current use of some asthma medications.
- Participants with second- or third-degree AV block or sinus node dysfunction
- Have a history of bleeding diathesis
- Have a history of clinically overt stroke
- Have a history of hypertension not adequately controlled with anti-hypertensive medications
- Participants who are receiving chronic anti-coagulation or anti-platelet therapy
- Participants with a history of metastatic cancer
- Participants may not be receiving any other study agents or have received a study agent in the past 30 days
- Participants with HIV
- Participants who have previously enrolled and received the investigational agent as part of this study
- Participants who are taking medications that may interact with the investigational agent