See the DrugPatentWatch profile for Fidaxomicin
What is fidaxomicin?
Fidaxomicin is a narrow‑spectrum macrolide antibiotic that treats infections caused by Clostridioides difficile. It is the active ingredient in the FDA‑approved drug Xifaxan. The drug works by inhibiting bacterial RNA polymerase, stopping the production of essential proteins in C. difficile.
Which brand name does fidaxomicin trade under?
The only brand name for fidaxomicin in the United States is Xifaxan. The name appears on the prescription label, but the generic name used in scientific and regulatory documents is fidaxomicin.
How does fidaxomicin compare to other treatments for C. difficile?
Clinical trials show fidaxomicin has a lower rate of infection recurrence compared with vancomycin and metronidazole. Its narrow spectrum also spares the normal gut microbiota, reducing the risk of secondary infections. However, its cost is higher and insurance coverage can vary.
What are the main side effects of fidaxomicin?
Common side effects include nausea, diarrhea, vomiting, and abdominal pain. Less frequently, patients may experience changes in liver enzymes or mild renal impairment. Severe allergic reactions are rare but possible.
Is there a generic fidaxomicin on the market?
Yes. After the patent protection for Xifaxan expired, generic fidaxomicin became available in 2024. Generic versions are identical in active ingredient and dosage but are typically offered at a lower price.
Who manufactures generic fidaxomicin?
Several specialty pharmaceutical companies now produce generic fidaxomicin, including Teva, Mylan, and Sandoz. Each submits a New Drug Application to the FDA that must demonstrate bioequivalence to the brand product.
How does the cost of generic fidaxomicin compare to the brand?
Generics are usually 30–60 % cheaper than Xifaxan. Exact savings depend on pharmacy pricing and insurance formularies. Patients should check with their insurer or pharmacist for the most accurate cost estimate.
Does the FDA approve the use of fidaxomicin in other countries?
Regulatory approval varies by country. In the European Union, the European Medicines Agency approved fidaxomicin in 2015 under the name Xifaxan. Other regions may use different brand names but the drug itself remains fidaxomicin.
What should a patient know before starting fidaxomicin?
Patients should inform their provider of any history of liver disease, kidney problems, or drug allergies. Fidaxomicin should be taken with or without food, but it must be swallowed whole and not crushed or chewed.
Are there any notable safety concerns?
The FDA has issued a boxed warning for a rare but serious risk of hypoglycemia in infants, particularly if mothers are nursing while on fidaxomicin. Pregnant women and nursing mothers should consult their clinician before use.
Where can I find more detailed prescribing information?
The full prescribing information, including dosing, contraindications, and detailed safety data, is available in the FDA’s drug label database and on the manufacturer’s website.