Widebac50 mg/vial

Widebac is a broad-spectrum intravenous glycylcycline antibiotic active against many multidrug-resistant organisms. Because of a boxed warning for increased mortality risk relative to other antibiotics, it is generally reserved for situations in which alternative treatment options are not suitable.

FDA-approved indications

• Complicated skin and skin structure infections (cSSSI) caused by susceptible organisms.
• Complicated intra-abdominal infections (cIAI) caused by susceptible organisms.
• Community-acquired bacterial pneumonia (CABP) caused by susceptible organisms.

Other/limited-use indications

• Used as part of combination regimens for selected infections caused by multidrug-resistant Gram-negative organisms (e.g. carbapenem-resistant Enterobacterales, Acinetobacter baumannii) when guided by susceptibility testing and infectious disease specialist input; this is an off-label/adjunct use reserved for infections with limited alternative options.

Widebac is not indicated for treatment of diabetic foot infections or hospital-acquired/ventilator-associated pneumonia, for which clinical trials showed inferior outcomes.

Each single-use vial contains Tigecycline 50 mg as a lyophilized (freeze-dried) orange powder for reconstitution and further dilution prior to intravenous infusion. No preservatives are included; the reconstituted solution is for single use only.

Widebac is a glycylcycline-class antibiotic, structurally related to the tetracyclines (a minocycline derivative), developed to overcome common bacterial resistance mechanisms — efflux pumps and ribosomal protection — that limit the usefulness of older tetracyclines. It is administered only by intravenous infusion and has broad-spectrum activity against many Gram-positive, Gram-negative, atypical, and anaerobic organisms, including numerous multidrug-resistant strains such as MRSA and vancomycin-resistant enterococci.

Because clinical trials showed a higher risk of death with Widebac compared with other antibiotics across a range of infection types, it carries a boxed warning and is generally reserved for infections where alternative agents are not suitable.

Glycylcycline antibiotic (a tetracycline-class derivative); Widebac is the first agent in this class.

Mechanism

Tigecycline inhibits bacterial protein synthesis by binding to the 30S ribosomal subunit and blocking entry of aminoacyl-tRNA molecules into the ribosomal A site, which prevents incorporation of amino acids into growing peptide chains. This action is primarily bacteriostatic. Structural modification at the D-ring of the tetracycline core allows Tigecycline to evade the two major tetracycline-resistance mechanisms (efflux pumps and ribosomal protection proteins), giving it activity against many tetracycline-resistant organisms.

Pharmacokinetics

• Distribution: Large volume of distribution; extensive tissue penetration; roughly 71–89% protein bound (concentration-dependent).
• Metabolism: Minimal hepatic metabolism; largely eliminated unchanged.
• Elimination: Primarily biliary/fecal excretion of unchanged drug and glucuronide metabolites, with a smaller fraction renally excreted. Terminal half-life is approximately 27–43 hours (multiple dose).
• Special populations: Exposure is increased in severe hepatic impairment (Child-Pugh C), requiring dose reduction; no dose adjustment is needed for renal impairment or dialysis.

Widebac is for intravenous infusion only — it must never be given by intramuscular, subcutaneous, or bolus injection. After reconstitution and dilution in a compatible IV solution, infuse over approximately 30 to 60 minutes. It should be administered under close medical supervision by a qualified healthcare professional, typically in a hospital setting. Do not mix in the same IV line with other medications unless compatibility has been confirmed; flush the line appropriately before and after infusion if it is used for other drugs.

Clinically significant interactions

• Warfarin and other oral anticoagulants: Widebac can increase prothrombin time/INR, raising bleeding risk. Monitor coagulation parameters closely when co-administered and adjust anticoagulant dose as needed.
• Hormonal contraceptives: As with other tetracycline-class agents, Widebac may theoretically reduce the effectiveness of oral contraceptives; an additional non-hormonal method of contraception is advisable during treatment.
• Other hepatotoxic drugs: Concurrent use with other medicines known to affect the liver may increase the risk of liver injury (see Precautions and Warnings); liver function should be monitored.

Widebac is a substrate of P-glycoprotein; strong P-glycoprotein inhibitors or inducers could theoretically alter its exposure, though clinical significance is not well established. Always inform your physician about all other medicines, supplements, and herbal products being used.

Very common / common

• Nausea and vomiting (among the most frequent reasons for discontinuation)
• Diarrhea
• Abdominal pain, dyspepsia
• Headache, dizziness
• Injection/infusion site reactions (pain, inflammation, phlebitis)
• Elevated liver enzymes (transaminases)

Serious (see Precautions and Warnings for full detail)

• Increased risk of death compared with other antibiotics (boxed warning)
• Hepatotoxicity, including liver failure
• Acute pancreatitis
• Clostridioides difficile-associated diarrhea, ranging from mild to life-threatening colitis
• Severe hypersensitivity reactions, including anaphylaxis and severe skin reactions
• Tooth discoloration/enamel hypoplasia if exposed during tooth development

Report any severe, persistent, or worsening symptoms to your physician promptly.

Pregnancy: Widebac, like other tetracycline-class drugs, can cause permanent tooth discoloration and reversible inhibition of bone growth in the developing fetus when used during the second and third trimesters, and may cause other fetal harm. Widebac should be used during pregnancy only if clearly needed and if the potential benefit to the mother justifies the potential risk to the fetus; consult a physician before use if pregnancy is known or suspected.

Lactation: It is not known whether Widebac passes into human breast milk in clinically relevant amounts. Because of the potential for tooth and bone effects in the infant, a decision should be made whether to discontinue breastfeeding or discontinue Widebac, taking into account the importance of the drug to the mother; consult a physician.

Boxed warning — increased mortality

In clinical trials pooling data across approved and non-approved indications, patients treated with Widebac had a higher risk of death compared with those treated with other antibiotics. The cause of this increased mortality has not been fully established but may be related to inadequate treatment of some infections and/or overall safety profile. Widebac should be reserved for use in situations when alternative treatments are not suitable.

Hepatotoxicity

Cases of liver injury, hepatic cholestasis, jaundice, and liver failure (some fatal) have been reported. Monitor liver function during treatment, particularly in patients with pre-existing hepatic impairment.

Pancreatitis

Acute pancreatitis, including fatal cases, has occurred. Consider this diagnosis in patients who develop abdominal pain, nausea, or vomiting, especially those without other risk factors; discontinue if pancreatitis is suspected.

Tooth and bone effects

As a tetracycline-class agent, Widebac can cause permanent tooth discoloration and enamel hypoplasia if used during tooth development (in utero through approximately 8 years of age), and can reversibly inhibit bone growth. Avoid use in this age group unless no suitable alternative exists.

Anti-anabolic effect

Tetracycline-class drugs, including Widebac, have been associated with an anti-anabolic action that may increase blood urea nitrogen (BUN) and has been linked to azotemia, acidosis, and hyperphosphatemia; monitor patients with pre-existing renal impairment.

Other precautions

• Clostridioides difficile-associated diarrhea (CDAD): May occur during or up to several months after treatment; evaluate if diarrhea develops.
• Photosensitivity: As with other tetracyclines, minimize excessive sun/UV exposure during treatment.
• Superinfection: Prolonged use may result in overgrowth of non-susceptible organisms, including fungi.
• Antimicrobial stewardship: Take exactly as prescribed by your physician; do not stop, extend, skip doses, or share this medicine with others without medical advice.

There is no specific antidote for Widebac overdose, and it is not significantly removed by hemodialysis. If an overdose is suspected, seek immediate medical attention or contact emergency services/a poison control center right away. Management is supportive, with close monitoring of vital signs and clinical status; treatment should be guided by a physician based on the patient's condition.

Store unopened vials of Widebac in a refrigerator (2°C to 8°C), protected from light. Do not freeze. After reconstitution and dilution, use the solution within the time and storage conditions specified by the dispensing pharmacist/manufacturer, and discard any unused portion. Keep out of reach of children.

• Hepatic impairment: No adjustment needed for mild-to-moderate impairment (Child-Pugh A/B). In severe impairment (Child-Pugh C), reduce the maintenance dose (see Dosage and Administration) and monitor closely.
• Renal impairment: No dose adjustment required, including in patients on hemodialysis.
• Elderly: No overall differences in safety or efficacy have been observed based on age alone; use with the same precautions as in younger adults.
• Pediatric patients: See Pediatric Uses.
• Pregnancy and lactation: See Pregnancy and Lactation.

Typical treatment duration with Widebac is 5 to 14 days for complicated skin and skin structure infections and complicated intra-abdominal infections, and 7 to 14 days for community-acquired bacterial pneumonia. The exact duration should be individualized by the treating physician based on the site and severity of infection, clinical response, and any complicating factors. Do not stop treatment early without medical advice, even if symptoms improve.

Reconstitute each 50 mg vial of Widebac with 5.3 mL of 0.9% Sodium Chloride Injection, 5% Dextrose Injection, or Lactated Ringer's Injection to yield a concentration of approximately 10 mg/mL. Gently swirl to dissolve (the reconstituted solution should appear yellow to orange in color; discard if discolored otherwise). Withdraw the required dose and further dilute in a 100 mL IV bag of a compatible diluent before infusion. Use reconstituted/diluted solution promptly, per pharmacy storage guidance, and discard any unused portion; each vial is for single use only.

Glycylcyclines (tetracycline-class antibiotic derivatives)

Tigecycline binds reversibly to the 30S ribosomal subunit of susceptible bacteria and blocks entry of aminoacyl-tRNA into the ribosomal A site, thereby inhibiting protein translation and bacterial growth (primarily bacteriostatic). Its glycylcycline structure — modified at the tetracycline D-ring — sterically hinders the two principal tetracycline-resistance mechanisms (efflux pumps and ribosomal protection proteins), which is why Tigecycline retains activity against many bacteria that are resistant to older tetracyclines.

D

Safety and effectiveness of Widebac for its approved indications have not been firmly established in pediatric patients under 18 years of age in the same way as in adults, and pediatric use should only occur under specialist guidance when no suitable alternative therapy is available. Widebac, like other tetracycline-class drugs, can cause permanent tooth discoloration (yellow-gray-brown) and enamel hypoplasia when used during tooth development — from the last half of pregnancy through approximately 8 years of age — and may reversibly inhibit bone growth. For this reason, use in children under 8 years is generally avoided unless the benefit clearly outweighs this risk, and the boxed warning regarding increased mortality applies in this age group as well. Any pediatric use requires close monitoring by a physician experienced in managing serious infections.