Recommendations for Handling Influenza Resistance

Edina Avdic, PharmD, MBA, BCPS-AQ ID, discusses her recommendations for treating patients demonstrating resistance to influenza treatments. This video was filmed at the 54th ASHP (American Society of Health-System Pharmacists) Midyear Meeting.

Edina Avdic, PharmD, MBA, BCPS-AQ ID: For the patients that may have resistance development to oseltamivir, zanamivir may still work, although some strains are occasionally resistant to zanamivir as well. And then most recently, baloxavir is a new agent that was FDA approved for use of influenza, and resistance rates to this agent, based on the clinical trials, is actually significantly higher compared to what we have seen so far with neuraminidase inhibitors. So what I would suggest, and we do have IDSA as well as CDC guidelines, is for clinicians to check on a regular basis the CDC updates on the activity of influenza. And [the] CDC will generally do some surveillance testing and reporting if we’re seeing certain strains of influenza that are resistant to the currently available therapies, and whether or not those current therapies should be avoided or if there are particular strains that are circulating in a certain region. So that’s probably the first place that I would do. I think that, if clinicians are concerned for patients that may have a resistance, that usually occurs in patients who might have been treated or received chemoprophylaxis. And in those instances, if, let’s say, a patient is not improving after they’ve been treated for 7 to 10 days, one consideration that clinicians can do is to contact the CDC and have a consultation on whether or not resistance testing should be considered.