Obiltoxaximab: uses, dosing, side effects & brands
Obiltoxaximab is an anthrax protective antigen-directed antibody sold in the U.S. under one brand, for anthrax, crohn disease and graft vs host disease. Below: what the FDA label says, every product that contains it, what the pills look like, and its recall record.
Key facts
- Drug class
- Anthrax Protective Antigen-Directed Antibody
- Treats
- Anthrax, Crohn Disease and Graft Vs Host Disease
- Available as
- Solution
- Sold as
- Anthim
- Prescription?
- Prescription only
- Generic available?
- Not in our catalog
- Boxed warning
- Boxed warning
How obiltoxaximab is dosed
From the FDA label for Anthim (application BLA125509). Other obiltoxaximab products — different forms, different strengths — are dosed differently. Follow the label for the one you were prescribed.
Pre-medicate with diphenhydramine. ( 2.1 , 5.1 ) Recommended Dosage of ANTHIM: Adult Patients: 16 mg/kg. ( 2.1 ) Pediatric Patients: ( 2.2 ) ➢ Greater than 40 kg: 16 mg/kg ➢ Greater than 15 kg to 40 kg: 24 mg/kg ➢ Less than or equal to 15 kg: 32 mg/kg Dilute the injection in 0.9% Sodium Chloride Injection, USP, before administering as an intravenous (IV) infusion over 1 hour and 30 minutes. ( 2.3 ) Administer ANTHIM in a monitored setting equipped to manage anaphylaxis. ( 2.4 , 5.1 ) See Full Prescribing Information for instructions on preparation, dilution and administration of ANTHIM injection. ( 2.3 , 2.4 ) 2.1 Dosage for Adult Patients Pre-medicate with diphenhydramine prior to administering ANTHIM [see Warnings and Precautions ( 5.1 )] . Dilute the injection in 0.9% Sodium Chloride Injection, USP, before administering as an intravenous infusion [see Dosage and Administration ( 2.3 )] . The recommended dosage of ANTHIM in adult patients is a single dose of 16 mg/kg administered intravenously over 90 minutes (1 hour and 30 minutes) [see Dosage and Administration ( 2.4 )] . For adult patients weighing less than 40 kg, see Table 1 below. 2.2 Dosage for Pediatric Patients Pre-medicate with diphenhydramine prior to administering ANTHIM [see Warnings and Precautions ( 5.1 )]. Dilute the injection in 0.9% Sodium Chloride Injection, USP, before administering as an intravenous…
Obiltoxaximab side effects
The following clinically important adverse reactions are described elsewhere in the labeling: Hypersensitivity and Anaphylaxis [see Warnings and Precautions ( 5.1 )]. Most frequently reported adverse reactions in healthy adult subjects (≥1.5%) were headache, pruritus, infections of the upper respiratory tract, cough, vessel puncture site bruise, infusion site swelling, nasal congestion, infusion site pain, urticaria and pain in extremity. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Elusys Therapeutics, Inc. at 1-844-808-0222 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The safety of ANTHIM has been studied only in healthy volunteers. It has not been studied in patients with inhalational anthrax. The safety of ANTHIM was evaluated in 320 healthy subjects treated with one or more 16 mg/kg IV doses in three clinical studies. Study 1 was a placebo-controlled study evaluating a single dose of ANTHIM vs. placebo (210 subjects received ANTHIM, 70 received placebo). Study 2 was a repeat-dose study in which 70 subjects received the first dose, but 34 and 31 subjects received a…
Who shouldn’t take obiltoxaximab
None. None ( 4 )
Obiltoxaximab drug interactions
7.1 Ciprofloxacin Co-administration of 16 mg/kg ANTHIM intravenously with intravenous or oral ciprofloxacin in human subjects did not alter the PK of either ciprofloxacin or obiltoxaximab [see Clinical Pharmacology ( 12.3 )] .
Every obiltoxaximab product we track (1)
Same active ingredient — different manufacturer, form, price and FDA recall record. That last one is what our independent score measures.
Only one: Anthim.
Obiltoxaximab and breastfeeding
From LactMed, the US National Library of Medicine’s Drugs and Lactation Database — quoted, not rewritten.
Full LactMed record for obiltoxaximab: levels in milk, effects in breastfed infants, and the drugs it would consider insteadNo information is available on the clinical use of obiltoxaximab during breastfeeding. Because obiltoxaximab is a large protein molecule with a molecular weight of 148,000, the amount in milk is likely to be very low. It is also likely to be partially destroyed in the infant's gastrointestinal tract and absorption by the infant is probably minimal. Until more data become available, obiltoxaximab should be used with caution during breastfeeding, especially while nursing a newborn or preterm infant. Waiting for at least 2 weeks postpartum to resume therapy may minimize transfer to the infant.
National Institute of Child Health and Human Development, record revised November 15, 2023. LactMed states its information is not a substitute for professional judgement.
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Frequently asked questions
What is obiltoxaximab?
Anthim (Obiltoxaximab) is an anthrax protective antigen-directed antibody used to treat Anthrax, Crohn Disease, Graft Vs Host Disease.
What kind of drug is obiltoxaximab?
The FDA classifies obiltoxaximab as an anthrax protective antigen-directed antibody. If you are checking whether it is safe to combine with something else, the class is what matters — two drugs from the same class usually should not be stacked.
Can you take obiltoxaximab with other medicines?
It depends on the medicine. We check it against the FDA labels rather than guessing: our interaction checker searches each drug's own label for the other and quotes what it says, naming the section it came from. Run obiltoxaximab against whatever else you take — and remember that a label not naming a drug is not the same as that combination being safe.
What forms does obiltoxaximab come in?
Across the brands we track, obiltoxaximab is currently marketed as solution, per the FDA's National Drug Code Directory. Each form is dosed differently — follow the label for the exact product you were prescribed.
Is there a generic obiltoxaximab?
We do not currently list a generic-labelled obiltoxaximab product. That does not always mean none exists — it means none appears under a generic name in the FDA data we track. Ask your pharmacist.
Cite this page
- APA
- pharmaranks. (2026, July 24). Obiltoxaximab: uses, dosing, side effects & brands. https://pharmaranks.com/drugs/obiltoxaximab
- MLA
- “Obiltoxaximab: uses, dosing, side effects & brands.” pharmaranks, 24 July 2026, https://pharmaranks.com/drugs/obiltoxaximab.
We summarise public FDA and NIH sources — for a clinical claim, cite the primary source we link to as well.
Sources: FDA openFDA drug label, National Drug Code Directory, and Enforcement (recall) database. This page reproduces public FDA data and is not medical advice. Dosing is set by your prescriber.
Read the full FDA label for obiltoxaximab on DailyMed (NIH) ↗ — including its boxed warning in full.