A Phase 2 interventional study of CSL889 and Placebo in Sickle Cell Disease Vaso-occlusive Crisis, sponsored by CSL Behring. Recruiting at 30 sites in 3 countries. Open to participants aged 12 Years and older. Per ClinicalTrials.gov, last updated 2026-10-08.
Sponsored by CSL Behring (part of CSL Limited) · Phase 2, Interventional, and Treatment
This is a phase 2, randomized, multiple-dose, placebo-controlled study designed to evaluate the safety, efficacy, and pharmacokinetics (PK) of CSL889 (human hemopexin) when given intravenously (IV) to adults and adolescents with sickle cell disease (SCD) experiencing vaso-occlusive crises (VOC). The main objectives of the study are to evaluate the safety and tolerability of CSL889 in study participants, and to assess how CSL889 affects the time it takes for VOC to resolve in participants with SCD.
104 studies on the registry are indexed under Vaso-Occlusive Crises; 31 are open to participants now.
This study's planned enrollment of 70 is below the median of 81 across 86 interventional studies indexed under Vaso-Occlusive Crises.
Browse Vaso-Occlusive Crises studies →CSL Behring is the lead sponsor of 145 studies on the registry; 17 are open to participants now.
Of its 24 completed or terminated interventional studies of FDA-regulated products, 17 (71%) have results posted.
First submitted after CSL Behring became part of CSL Limited.
Compared within Vaso-Occlusive Crises, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Anemia, Sickle Cell. The counts are of registry records indexed under each term, refreshed daily. How we classify →
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
At the time of :
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
A “mini-stroke”: temporary stroke-like symptoms caused by reduced blood flow to part of the brain, spinal cord or eye, without signs of a new stroke on a scan.
Stroke symptoms need emergency care at once, even if they go away.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
TIA (transient ischaemic attack)
A “mini-stroke”: temporary stroke-like symptoms caused by reduced blood flow to part of the brain, spinal cord or eye, without signs of a new stroke on a scan.
Stroke symptoms need emergency care at once, even if they go away.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants in this arm will receive CSL889 as per regimen 1.
Biological: CSL889
Participants in this arm will receive CSL889 as per regimen 2.
Biological: CSL889
Participants in this arm will receive placebo matching to CSL889 regimen.
Drug: Placebo
CSL889 is a solution for infusion to be administered by the IV route.
Also known as: Hemopexin, human
Volume and regimen matched to CSL889 will be administered.
Number of participants with treatment-emergent adverse events (TEAEs)
Time frame: Up to Day 28 (End of study [EOS] Visit)
Percentage of participants with TEAEs
Time frame: Up to Day 28 (EOS Visit)
Number of participants with detectable treatment emergent (TE) anti-CSL889 antibodies
Time frame: Up to Day 28 (EOS Visit)
Percentage of participants with detectable TE anti-CSL889 antibodies
Time frame: Up to Day 28 (EOS Visit)
Time to resolution of VOC (time to discontinuation of parenteral opioids)
Time frame: Up to Day 28 (EOS Visit)
Hospital admission rate
Hospital admission rate in participants with SCD presenting with VOC who received greater than or equal to (≥) 1 dose of CSL889 in the acute care setting.
Time frame: Up to Day 28 (EOS Visit)
Length of hospital stay (If hospitalized)
Time frame: Up to Day 28 (EOS Visit)
Percentage of participants experiencing acute chest syndrome (ACS), acute kidney injury (AKI), or stroke
Time frame: From the start of investigational product (IP) administration up to Day 8
Length of acute care stay
Time frame: Up to Day 28 (EOS Visit)
Total Length of acute care and hospital stay
Time frame: Up to Day 28 (EOS Visit)
Re-presentation rate to an acute care facility for VOC or ACS after discharge
Time frame: From discharge up to Day 28
Hospital admission rate for VOC or ACS after discharge
Time frame: From discharge up to Day 28
Opioid consumption
Opioid consumption will be measured in morphine milligram equivalent units.
Time frame: From the time of enrollment to discharge (up to Day 28 [EOS Visit])
Number of participants with ≥ 30% pain reduction by Numeric Rating Scale (NRS) score
The NRS for pain is a validated self-reported 11-point pain severity scale (where 0 means no pain and 10 means the most or worst possible pain) that can be used in adults, adolescents, and children ≥ 8 years of age with SCD.
Time frame: Within 4 hours after the start of CSL889 infusion
Percentage of participants with ≥ 30% pain reduction by NRS score
The NRS for pain is a validated self-reported 11-point pain severity scale (where 0 means no pain and 10 means the most or worst possible pain) that can be used in adults, adolescents, and children ≥ 8 years of age with SCD.
Time frame: Within 4 hours after the start of CSL889 infusion
Maximum observed concentration (Cmax) after Doses 1 and 3 of CSL889
Time frame: Before dosing, and up to 12 hours after Doses 1 and 3
Area under the concentration (AUCtau) after Doses 1 and 3 of CSL889
Time frame: Before dosing, and up to 12 hours after Doses 1 and 3
Time of maximum concentration (Tmax) after Doses 1 and 3 of CSL889
Time frame: Before dosing, and up to 12 hours after Doses 1 and 3
Trough concentration (Ctrough) after each dose of CSL889
Time frame: Up to Day 5
Accumulation ratio (AR) for AUCtau of CSL889 (the ratio between the AUCtau of Doses 3 and 1)
Time frame: Before dosing and at up to 12 hours after Doses 1 and 3
AR for Cmax of CSL889 (the ratio between the Cmax of Doses 3 and 1)
Time frame: Before dosing and at up to 12 hours after Doses 1 and 3
AR for Ctrough of CSL889 (the ratio between the Ctrough of the last dose and Dose 1)
Time frame: Before dosing and after Dose 1 and the last dose
Cmax after each dose in Sparse PK subset of CSL889
Sparse PK blood sampling will be performed in remainder of participants who are not in the Adult or Adolescent PK Subsets.
Time frame: Up to Day 5
Ctrough after each dose in Sparse PK subset of CSL889
Sparse PK blood sampling will be performed in remainder of participants who are not in the Adult or Adolescent PK Subsets.
Time frame: Up to Day 5
AR for Cmax in Sparse PK subset of CSL889
Sparse PK blood sampling will be performed in remainder of participants who are not in the Adult or Adolescent PK Subsets.
Time frame: Up to Day 5
AR for Ctrough in Sparse PK subset of CSL889
Sparse PK blood sampling will be performed in remainder of participants who are not in the Adult or Adolescent PK Subsets.
Time frame: Up to Day 5
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Plan to share: Yes — CSL will consider on a case-by-case basis requests to share Individual Patient Data (IPD) with external bona-fide, qualified scientific and medical researchers. For information on the process and requirements for submitting a voluntary data sharing request for IPD, please contact CSL at clinicaltrials@cslbehring.com.
Supporting information: Study protocol, Statistical analysis plan
Time frame: Requests for IPD will generally be considered once review by major regulatory authorities (i.e. FDA, EMA) is complete and the primary publication is available
Access criteria: Proposed research should seek to answer a previously unanswered important medical or scientific question. Applicable country specific privacy and other laws and regulations will be considered and may prevent sharing of IPD. If the request is approved and the researcher has executed an appropriate data sharing agreement, IPD that has been appropriately anonymized will be available.
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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