Xofluza (zoh-FLOO-zuh, baloxavir) will be the first new oral antiviral for treating influenza in nearly 20 years.
Think of Xofluza as an alternative to oseltamivir (Tamiflu).
A big difference is Xofluza is ONE oral dose...compared to 5 days of BID oseltamivir. Xofluza also seems to cause less nausea and vomiting.
Xofluza has a new antiviral mechanism. But either Xofluza or oseltamivir only reduces flu symptoms by about a day in otherwise healthy patients...if started within 48 hours of onset.
Plus there's limited or no evidence for Xofluza in the high-risk patients who benefit most from antivirals...such as those under age 2 or 65 and older, with chronic conditions (asthma, etc), or pregnant women.
And some experts are concerned about early suggestions of Xofluza resistance. It's too soon to say how this will pan out clinically.
Xofluza will cost about $150...versus about $100 for 5 days of generic oseltamivir. But some payers may not cover Xofluza.
For now, stick with oseltamivir to treat flu in high-risk or severely ill patients...and start ASAP after symptom onset.
Don't feel compelled to prescribe any antiviral for most otherwise healthy patients. Instead recommend rest, fluids, analgesics, etc.
But if these patients insist, it's okay to consider Xofluza instead of oseltamivir in those 12 and older...IF they can start within 48 hours.
Advise not to take Xofluza at the same time as dairy or products with calcium, aluminum, iron, etc...these may impair Xofluza's absorption.
Don't combine antivirals...or use another antiviral if the first doesn't help. There's no evidence to support this.
Continue to emphasize flu vaccination to help PREVENT the flu.
Choose oseltamivir if high-risk patients need an antiviral for prophylaxis. So far, Xofluza is only for TREATING flu.
Use our chart, Antivirals for Influenza, for Xofluza dosing...and to see how the Relenza (zanamivir) inhaler compares.
- N Engl J Med 2018;379(10):913-23
- N Engl J Med 2018;379(10):975-7
- Lancet 2015;385(9979):1729-37
- Medication pricing by Elsevier, accessed Nov 2018
- Chart: Antivirals for Influenza