Peramivir: An Alternative IV Influenza Treatment

When it comes to influenza treatment, oseltamivir is often the first medication considered, but could peramivir be an alternative in inpatient settings?

The journal Infection and Drug Resistance published a literature review in its August 2016 issue that discussed peramivir’s role in acute influenza treatment, as well as its mechanism of action, pharmacology, clinical efficacy, safety, tolerability, and current place in therapy.

Influenza causes more than 36,000 US deaths and 300,000 to 500,000 deaths globally each year. The 2009 H1N1 pandemic alone was responsible for at least 273,304 hospitalizations and 12,469 deaths worldwide. Additionally, because the circulating H1N1 viruses were resistant to M2 channel inhibitors, including amantadine, the pandemic emphasized the need for more effective antiviral agents.

During the pandemic, the FDA issued an Emergency Use Authorization for peramivir in (1) patients unresponsive to or unable to tolerate other antivirals, or (2) situations where oral/inhaled routes were considered unreliable. The only treatment-emergent adverse event with its use during this period was rash development.

Peramivir selectively inhibits influenza’s viral neuraminidase, thus preventing infected cells from releasing virus particles. Compared with oseltamivir, zanamivir, and laninamivir, peramivir has a much higher affinity for the neuraminidase. Additionally, peramivir’s long half-life allows for convenient once-daily dosing.

Unlike oseltamivir, which is metabolized almost entirely in the liver, peramivir’s elimination is primarily renal. Dosage adjustments are warranted in patients with renal dysfunction.

Peramivir may be particularly beneficial in the inpatient setting due to its route of administration. Unlike oseltamivir, which is administered orally, and zanamivir, which is inhaled, peramivir is administered intravenously or intramuscularly. Peramivir may be an attractive option in patients with severe influenza who are mechanically ventilated or critically ill; however, studies have also demonstrated that enteral oseltamivir is adequately absorbed in critically ill adults, resulting in therapeutic blood levels after administration of standard doses.

Although several trials have demonstrated peramivir’s noninferiority to oseltamivir, more studies are required to assess its effect on hospitalizations and mortality. Currently, case reports and retrospective studies support using peramivir in special populations, including pediatric, pregnant women, and patients undergoing continuous renal replacement therapy and extracorporeal membrane oxygenation; however, clinical trials are still needed to establish its clinical efficacy in these populations.

Overall, peramivir appears to be a well-tolerated, convenient alternative in hospitalized influenza patients.