Obiltoxaximab (Anthim) is a high-affinity IgG1 monoclonal antibody that binds to B. Anthracis. It is used in the treatment and prophylaxis of inhalational anthrax.

Obiltoxaximab (Anthim) Uses:

• Inhalational anthrax:

  • Treatment of inhalational anthrax caused by Bacillus anthracis in combination with adequate antibacterial drugs.
  • Prophylaxis and prevention of inhalational anthrax due to B.anthracis when alternative ways of treatment are not available or not appropriate

• Limitations of use:

  • Should only be used for prophylaxis and prevention and when the benefit for prevention of inhalational anthrax is higher than the risk of hypersensitivity and anaphylaxis

Obiltoxaximab Dose in Adults

Obiltoxaximab Dose in the treatment and prophylaxis of inhalational Anthrax:

Note: Premedicate with diphenhydramine prior to infusion.

• <40 kg: 24 mg/kg/dose as a single dose
• >40 kg: 16 mg/kg/dose as a single dose

Obiltoxaximab Dose in Childrens

Obiltoxaximab Dose in the treatment and prophylaxis of Inhalational Anthrax:

• Infants, Children, and Adolescents: IV:

  • ≤15 kg: 32 mg/kg as a single dose
  • >15 kg to 40 kg: 24 mg/kg in form of single dose
  • >40 kg: 16 mg/kg as a single dose

Pregnancy Risk Factor B

• In animal reproduction studies, adverse events were not reported.
• The guidelines for treatment and prophylaxis of inhalational Anthrax in pregnant and postpartum mothers are generally the same as those for adults.

Obiltoxaximab use during breastfeeding:

• It is unknown if the drug is found in breast milk.
• Breast milk contains immunoglobulins, which are excreted in breastmilk.
• Although it is unlikely that breast milk will absorb a lot, their potential effects are unknown.
• The guidelines for treatment and prophylaxis of inhalational Anthrax in lactating mothers are generally the same as those in non-pregnant women.

Obiltoxaximab  Dose in Kidney Disease:

• There are no dosage adjustments provided in the drug maker's labeling

Obiltoxaximab Dose in Liver disease:

• There are no dosage adjustments provided in the drug maker's labeling

Side Effects of Obiltoxaximab (Anthim):

• Central nervous system:

  • Headache
  • Dizziness
  • Fatigue
  • Voice Disorder

• Cardiovascular:

  • Chest Discomfort
  • Chest Pain
  • Palpitations

• Dermatologic:

  • Skin Rash
  • Pruritus
  • Urticaria

• Gastrointestinal:

  • Vomiting
  • Xerostomia

• Hematologic & Oncologic:

  • Abnormal Lymphocyte Count
  • Change In Neutrophil Count
  • Decreased White Blood Cell Count

• Hypersensitivity:

  • Hypersensitivity Reaction

• Immunologic:

  • Antibody Development

• Local:

  • Infusion Site Reaction
  • Bruising At Injection Site
  • Local Discoloration

• Neuromuscular & Skeletal:

  • Limb Pain
  • Increased Creatine Phosphokinase
  • Musculoskeletal Pain
  • Myalgia

• Respiratory:

  • Cough
  • Upper Respiratory Tract Infection
  • Throat Irritation
  • Rhinorrhea
  • Nasal Congestion
  • Cyanosis
  • Dyspnea
  • Oropharyngeal Pain
  • Sinus Congestion

• Miscellaneous:

  • Fever
  • Infusion Related Reaction

Contraindications to Obiltoxaximab (Anthim):

• The manufacturer's labeling does not list any contraindications.

Warnings and precautions

• Hypersensitivity [US Boxed Warning]

  • Hypersensitivity and anaphylactic reactions may occur (eg, rash/urticaria or cough, dyspnea or cyanosis),
  • In a controlled setting, administer the medication.
  • Monitor patients carefully for hypersensitivity symptoms during and after infusions.
  • If you experience anaphylactic reactions or hypersensitivity, stop the infusion immediately and treat it accordingly.

Monitoring parameters:

• Monitor patients closely for signs and symptoms of hypersensitivity during and after the infusion.

How to administer Obiltoxaximab (Anthim)?

• IV:
  • Premedication with diphenhydramine is recommended.
  • Administer a prepared solution (IV infusion bag or syringe) using a 0.22-micron inline filter over 1 hour and 30 minutes.
  • Flush the line with Normal Saline at the end of the infusion.

Mechanism of action of Obiltoxaximab (Anthim):

• Obiltoxaximab, a monoclonal anti-anthrax antibody, attaches the B.anthracis toxins free protective antigenic portion to the cell.
• This prevents intracellular entry of anthrax Lethal and Edema factors, which are the enzymatic components that cause the anthrax toxin's pathogenic effects.

Distribution:

• Greater than plasma volume (eg, some tissue distribution).

Excretion:

• Minimal renal elimination

Obiltoxaximab International Brand Names:

• Anthim
• Anthrax antitoxin

Obiltoxaximab Brand Names in Pakistan:

No Brands Available in Pakistan.