An observational study in Infections, Bacterial, sponsored by Emergent BioSolutions. Not yet recruiting. Per ClinicalTrials.gov, last updated 2026-03-17.
Sponsored by Emergent BioSolutions · Observational
This observational, open-label, single arm, study is designed such that it may be implemented for any individual with a lab confirmed sporadic case of systemic anthrax disease treated with raxibacumab outside of the current United States Prescribing Information (USPI). Systemic anthrax cases may include inhalational, gastrointestinal and injectional anthrax, anthrax meningitis or bacteremia or cutaneous anthrax with systemic effects.
This study is designed to evaluate the clinical effectiveness (including course of illness and survival), safety profile and pharmacokinetic (PK) analysis of raxibacumab from patients who are treated with raxibacumab as part of their clinical care following exposure to B. anthracis. Study data, PK sample provision/collection and other investigational research will be collected prospectively to the extent possible at pre-specified time points. However, there is no reasonable way to identify prospectively the individuals likely to become eligible for participation in this study so most data in this study is anticipated to be collected retrospectively. Scavenged blood samples will be utilized where possible to maximize sample analyses and other investigational parameters. Therefore, both retrospective and prospective data collection are allowed in this protocol in order to maximize the amount of information obtained in subjects who have been administered raxibacumab. This field study will be the first opportunity to collect data on B. anthracis-exposed patients treated with raxibacumab, to better understand the clinical benefit and safety of the drug and to further inform patient care and treatment choices for management of anthrax.
The protocol is a post-marketing requirement from the FDA to evaluate the clinical benefit, safety and pharmacokinetic analysis of raxibacumab administered to patients with lab confirmed systemic anthrax disease as part of their medical care following exposure to Bacillus anthracis.
75 studies on the registry are indexed under Anthrax; 12 are open to participants now.
This study's planned enrollment of 10 is below the median of 99 across 16 observational studies indexed under Anthrax.
Browse Anthrax studies →Emergent BioSolutions is the lead sponsor of 47 studies on the registry; 7 are open to participants now.
Of its 11 completed or terminated interventional studies of FDA-regulated products, 7 (64%) have results posted.
Compared within Anthrax, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Bacterial Infections. The counts are of registry records indexed under each term, refreshed daily. How we classify →
The population to be studied are patients with lab confirmed systemic anthrax who are treated with raxibacumab according to the USPI and distributed from the US SNS.
The population may include all age categories of patients (infant, pediatric, adult [including pregnant and lactating women], and geriatric) with confirmed systemic anthrax in the US.
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.
Note: Systemic anthrax is defined in this protocol as a clinically compatible case of gastrointestinal, injectional, or inhalational anthrax; anthrax meningitis or bacteremia; or cutaneous anthrax with systemic effects (i.e., tachycardia, tachypnea, hypotension, hyperthermia, hypothermia, leukocytosis) or with lesions that involve the head, neck or upper torso, or are large, bullous, multiple, or surrounded by significant edema; plus confirmation by one of the following: Epidemiological link to a documented anthrax environmental exposure and/or laboratory test used for confirmation of systemic anthrax diagnosis by one of the following:
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.
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.
This is an open-label, single arm study. The study will be implemented for subjects with lab confirmed systemic anthrax disease who receive FDA-approved raxibacumab as part of their clinical care. Intervention: Sampling of subjects or use of subjects salvaged standard of care samples may be considered for the following assessments (if available/applicable): pharmacokinetics (PK) analysis of antibodies to PA (anti-PA), protective antigen (PA), and lethal factor (LF)
Biological: Collection of samples
Whenever possible serum samples will be collected from all subjects to determine serum raxibacumab concentrations pre-infusion, and at specific timepoints post-infusion. In the event cerebrospinal fluid (CSF), pleural, ascites, or bronchoalveolar lavage (BAL) fluid are collected for ad hoc clinical laboratory testing, any remaining excess sample will be provided to Sponsor for determination of raxibacumab concentrations. Any available serum remaining from ad hoc clinical laboratory specimen collections prior to raxibacumab administration will be provided to Sponsor for measurement of serum PA concentrations. In addition, remaining post raxibacumab dose serum specimens may also be analyzed for lethal factor (LF) levels.
Clinical Benefit of Raxibacumab for Patients with Confirmed Systemic Anthrax Disease
The primary objective is: To evaluate the clinical benefit in patients with confirmed systemic anthrax disease, as assessed by overall mortality rate up to Day 29.
Time frame: Up to Day 29
Clinical Benefit of Raxibacumab for Patients with Confirmed Systemic Anthrax Disease
The primary objective is: To evaluate safety of raxibacumab in patients with confirmed systemic anthrax disease, as assessed by incidence of ADRs.
Time frame: Up to Day 29
Clinical Benefit of Raxibacumab for Patients with Confirmed Systemic Anthrax Disease
The primary objective is: To evaluate safety of raxibacumab in patients with confirmed systemic anthrax disease, as assessed by incidence of SAEs.
Time frame: Up to Day 29
To evaluate the clinical course of the disease in patients with confirmed systemic anthrax disease
The secondary objective is to evaluate the clinical course of the disease in patients with confirmed systemic anthrax disease assessed by Incidence of hospitalization
Time frame: Up to Day 29
To evaluate the clinical course of the disease in patients with confirmed systemic anthrax disease
The secondary objective is to evaluate the clinical course of the disease in patients with confirmed systemic anthrax disease assessed by length of hospitalization
Time frame: Up to Day 29
To evaluate the clinical course of the disease in patients with confirmed systemic anthrax disease
The secondary objective is to evaluate the clinical course of the disease in patients with confirmed systemic anthrax disease assessed by length of ICU stay.
Time frame: Up to Day 29
To evaluate the clinical course of the disease in patients with confirmed systemic anthrax disease
The secondary objective is to evaluate the clinical course of the disease in patients with confirmed systemic anthrax disease assessed by duration of mechanical ventilation
Time frame: Up to Day 29
To evaluate the clinical course of the disease in patients with confirmed systemic anthrax disease
The secondary objective is to evaluate the clinical course of the disease in patients with confirmed systemic anthrax disease assessed by incidence of ICU stay
Time frame: Up to Day 29
To evaluate the clinical course of the disease in patients with confirmed systemic anthrax disease
The secondary objective is to evaluate the clinical course of the disease in patients with confirmed systemic anthrax disease assessed by incidence of mechanical ventilation
Time frame: Up to Day 29
Anti-PA serum concentrations
Assess anti-PA serum concentrations to the extent that data permit.
Time frame: Up to Day 29
Anthrax toxin levels
Assess anthrax toxin levels to the extent that data permit.
Time frame: Up to Day 29
Raxibacumab PK in Relation to Anthrax Toxemia
Inform on raxibacumab PK parameter of Cmax, in relation to anthrax toxemia to the extent that the data permit.
Time frame: Up to Day 29
Raxibacumab PK in Relation to Anthrax Toxemia
Inform on raxibacumab PK parameter of AUC0-inf, in relation to anthrax toxemia to the extent that the data permit.
Time frame: Up to Day 29
Raxibacumab PK in Relation to Anthrax Toxemia
Inform on raxibacumab PK parameter of AUClast, in relation to anthrax toxemia to the extent that the data permit.
Time frame: Up to Day 29
Raxibacumab PK in Relation to Anthrax Toxemia
Inform on raxibacumab PK parameter of terminal phase elimination half-life, in relation to anthrax toxemia to the extent that the data permit.
Time frame: Up to Day 29
No study locations are listed for this record.
Plan to share: Undecided
No publications or documents are linked to this record.
Start is estimated for May 2027; primary completion for May 2030, 36 months later.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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