Brand Name: Sivextro
Generic Name: tedizolid phosphate
Medication Class: antibacterial
Similar Drugs: Zyvox (linezolid)
Manufacturer: Cubist Pharmaceuticals
FDA Approval Date: June 20, 2014
What is Sivextro and its mechanism of action?
Sivextro (tedizolid phosphate) is the prodrug (inactive form) of tedizolid, an oxazolidinone type antibiotic. After oral or intravenous administration it is converted to its active form by enzymes. Cells require vital cellular proteins for survival. Tedizolid, the active form of Sivextro, binds to cell structures that produce these essential proteins that allow bacterial cells to function and inactivates them. Because its mechanism of action differs from non-oxazolidinone class antibacterials, bacterial cross-resistance is unlikely. Tedizolid is active against enterococci, streptococci, and staphylococci.
What is Sivextro used for treating?
Sivextro is used for treating acute bacterial skin and skin structure infections (ABSSI) caused by bacteria classified as gram-positive bacteria. Susceptible bacteria include Staphylococcus aureus (including MRSA and MSSA), Enterococcus faecalis, Streptococcus pyogenes, Streptococcus agalactiae, and Streptococcus anginosus.
How effective is Sivextro?
Sivextro 200 mg once daily for six days was compared to linezolid 600 mg every 12 hours for 10 days in a total of 1315 adults with acute bacterial skin and skin structure infections (ABSSI) across two clinical trials. The types of ABSSI included were cellulitis/erysipelas, wound infection, and major cutaneous abscess. Sivextro 200 mg once daily for 6 days was shown to be just as effective or non-inferior to linezolid 600 mg twice daily for 10 days for treatment of patients with ABSSI.
Interesting facts about Sivextro
Sivextro is available in both intravenous (IV) and oral formulations, similar to Zyvox (linezolid).
Sivextro is the second drug to be approved by the FDA within the oxazolidinone antibacterial class, following Zyvox in 2000.
Dosage adjustments are not necessary in patients with reduced kidney or liver function.
What are the side effects of Sivextro?
Common: nausea, headache, diarrhea, vomiting, dizziness
Serious: Tachycardia (increased heart rate), Clostridium difficile colitis, neutropenia, optic nerve disorder and peripheral nerve disease
What is the dosage of Sivextro?
Sivextro is available in 200 mg tablets and a 200 mg IV formulation.
The recommended dose for oral administration is 200 mg once daily for 6 days without regards to meals or any dietary restrictions. The recommended dose for IV administration is 200 mg once daily for 6 days infused over one hour.
Patients should not skip or miss any doses. However, if a dose is missed the patient should take the dose as soon as possible. If less than 8 hours remain before their next scheduled dose, patients should wait until their next scheduled dose.
What are Sivextro drug interactions?
Sivextro is a reversible inhibitor of monoamine oxidase (MAO) enzymes and has the potential to have the same interactions as other MAO inhibitors, such as linezolid (Zyvox). Although the extent of these drug interactions as have not been fully determined during clinical trials, prescribers and health care professionals should not combine Sivextro with drugs that interact with Linezolid. Here are some examples:
Atomoxetine: Linezolid may enhance the central nervous system effects of atomoxetine if used concurrently. Thus, this combination should be avoided.
Brimonidine (Topical or Opthalmic): Concurrent use with Linezolid may prevent the breakdown of brimonidine. An increased concentration of brimonidine may result in enhanced adverse/toxic effects. Therapy should be monitored with concurrent use of linezolid and brimonidine.
Bupropion: Concurrent use with Linezolid may increase the hypertensive effects of Bupropion. Thus, this combination should be avoided.
Tapentadol: May enhance the adverse/toxic effects of Linezolid. This combination should be avoided.
Tramadol: May enhance the effect of Linezolid resulting in a serious reaction called serotonin syndrome or seizures. This combination should be avoided.
Selective serotonin reuptake inhibitors (SSRI) such as Prozac (fluoxetine) and serotonin norepinephrine reuptake inhibitors such as desvenlafaxine, and other drugs such as carbamazepine, amphetamine, and meperidine interact with linezolid and may also interact with Sivextro.
Combining tyramine containing foods with Sivextro may increase blood pressure to dangerous levels. Foods high in tyramine include aged cheeses, fermented meat, red wine, and fava beans.
What are warnings and precautions for Sivextro?
Neutropenia: Patients with neutropenia, a condition characterized by a low amount of white blood cells, have not been adequately evaluated while on Sivextro therapy. Alternative therapies should be considered in these types of patients.
Clostridium difficile-associated diarrhea (CDAD): Antibacterial agents may alter the natural flora in our colon resulting in a potential overgrowth of C. difficile. Sivextro should be discontinued if CDAD is suspected or confirmed.
Bacterial resistance: Skipping doses or not completing the full course of treatment may result in bacterial resistance and decreased effectiveness of therapy.
Pregnancy: Sivextro is a Pregnancy Category C medication. Category C means that it has not been adequately evaluated in pregnant women. Sivextro should only be used in pregnant patients if the benefits clearly outweigh the risks associated with Sivextro administration.
Nursing mothers: It is currently unknown whether tedizolid is excreted in human milk. However, extreme caution should be exercised if Sivextro is used by nursing mothers.
How to obtain prescription assistance for Sivextro
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