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Medically reviewed by Last updated on Sep 17, 2020.


(bez loe TOX ue mab)

Index Terms

  • MK-6072

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Solution, Intravenous [preservative free]:

Zinplava: 1000 mg/40 mL (40 mL) [contains polysorbate 80]

Brand Names: U.S.

  • Zinplava

Pharmacologic Category

  • Monoclonal Antibody


Bezlotoxumab is a human IgG1 monoclonal antibody which binds to C. difficile toxin B and neutralizes it to prevent its toxic effects; bezlotoxumab does not bind to C. difficile toxin A.


7.33 L


Metabolized via catabolism


Eliminated primarily through catabolism

Half-Life Elimination

~19 days

Use: Labeled Indications

Clostridioides (formerly Clostridium) difficile infection, adjunctive therapy: To reduce recurrence of Clostridioides (formerly Clostridium) difficile infection (CDI) in patients ≥18 years of age who are receiving antibacterial drug treatment of CDI and are at a high risk for CDI recurrence

Limitations of use: Bezlotoxumab is not indicated for the treatment of CDI. Bezlotoxumab is not an antibacterial drug and should only be used in conjunction with antibacterial drug treatment of CDI.


There are no contraindications listed in the manufacturer's labeling.

Dosing: Adult

Clostridioides (formerly Clostridium) difficile infection, adjunctive therapy: IV: 10 mg/kg as a single dose during antibacterial treatment for Clostridioides (formerly Clostridium) difficile infection. Repeat doses have not been studied.

Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.

Dosing: Geriatric

Refer to adult dosing.


Must be diluted prior to infusion. Immediately after removing vial from refrigerator, withdraw appropriate volume from vial and transfer to infusion bag of either normal saline or D5W to a final concentration between 1 to 10 mg/mL. Do not use vials if solution is discolored or if particulates are visible. Gently invert to mix; do not shake.


IV: Infuse IV over 60 minutes through a sterile, nonpyrogenic, low-protein binding 0.2 to 5 micron in-line or add-on filter. Do not administer as an IV push or bolus. May be infused via a central line or peripheral catheter. Do not coadminister other drugs simultaneously through the same infusion line. If infusion solution was refrigerated, allow to come to room temperature prior to administration. Infusion should be completed within 16 hours of preparation (if stored at room temperature) or within 24 hour (if refrigerated).


Store intact vials at 2°C to 8°C (36°F to 46°F). Do not freeze. Protect from light. Do not shake vials. Solutions diluted for infusion may be stored either at room temperature for up to 16 hours or refrigerated at 2°C to 8°C (36°F to 46°F) for up to 24 hours. Infusion must be completed within these time frames. If refrigerated, allow the intravenous bag to come to room temperature prior to use. Do not freeze diluted solution.

Drug Interactions

There are no known significant interactions.

Adverse Reactions

The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified.

>10%: Cardiovascular: Cardiac failure (exacerbation:13%)

1% to 10%:

Cardiovascular: Cardiac failure (2%)

Central nervous system: Headache (4%)

Gastrointestinal: Nausea (7%)

Miscellaneous: Infusion related reaction (10%; including nausea, fatigue, fever, dizziness, headache, dyspnea, and hypertension), fever (5%)

<1%, postmarketing, and/or case reports: Ventricular tachyarrhythmia


Concerns related to adverse effects:

• Heart failure: Heart failure has been reported at a higher rate in patients treated with bezlotoxumab (compared to placebo), primarily occurring in patients with underlying heart failure. Additionally, a higher mortality rate due to cardiac failure, infection, and respiratory failure was observed in patients with a history of heart failure who received bezlotoxumab (compared to those who received placebo). In patients with a history of heart failure, bezlotoxumab use should be reserved for situations when the benefits outweigh risks.

Pregnancy Considerations

Bezlotoxumab is a humanized monoclonal antibody (IgG1). Potential placental transfer of human IgG is dependent upon the IgG subclass and gestational age, generally increasing as pregnancy progresses. The lowest exposure would be expected during the period of organogenesis (Palmeira 2012; Pentsuk 2009).

Patient Education

What is this drug used for?

• It is used to lower the chance of a type of bacterial infection called C. diff from coming back.

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Nausea

• Loss of strength and energy

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Severe headache

• Dizziness

• Passing out

• Vision changes

• Heart problems like cough or shortness of breath that is new or worse, swelling of the ankles or legs, abnormal heartbeat, weight gain of more than five pounds in 24 hours, dizziness, or passing out

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a limited summary of general information about the medicine's uses from the patient education leaflet and is not intended to be comprehensive. This limited summary does NOT include all information available about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not intended to provide medical advice, diagnosis or treatment and does not replace information you receive from the healthcare provider. For a more detailed summary of information about the risks and benefits of using this medicine, please speak with your healthcare provider and review the entire patient education leaflet.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.