zanamivir
Regulatory sources consulted
Approved indications
- Treatment of influenza A and B in patients aged 7 years and older with symptoms for less than 48 hours and prophylaxis in patients aged 5 years and older.
Contraindications
Absolute
- Hypersensitivity to zanamivir or milk proteins present in the lactose formulation.
Clinical warnings
- It may cause severe bronchospasm or respiratory deterioration; it is not recommended in asthma or COPD. Stop and treat immediately if it occurs. — CIMA/AEMPS, ficha técnica 62712
- Do not prepare nebulizer solutions from the powder or administer it through mechanical ventilation. — CIMA/AEMPS, ficha técnica 62712
Drug interactions
- HighIntranasal live attenuated influenza vaccine
Mechanism: The antiviral may reduce vaccine replication and efficacy.
Recommendation: Do not administer live attenuated vaccine within 2 weeks before or 48 hours after zanamivir unless medically indicated.
CIMA/AEMPS, ficha técnica 62712
Adverse events
Common (≥1%)
Headache and nasal or throat symptoms
Rare but serious
Bronchospasm, anaphylactic reaction, severe skin reaction, and neuropsychiatric events
Pregnancy and lactation
It may be considered during pregnancy and breastfeeding when expected benefit outweighs risk.
Recent literature (PubMed)
Flu is a serious health, medical, and economic problem, but no therapy is yet available that has satisfactory results and reduces the occurrence of these problems. Nearly 20 years after the registration of the previous therapy, baloxavir marboxil, a drug with a new mechanism of action, recently appeared on the market. This is a promising step in the fight against the influenza virus. This article presents the possibilities of using all available antiviral drugs specific for influenza A and B. We compare all currently recommended anti-influenza medications, considering their mechanisms of action, administration, indications, target groups, effectiveness, and safety profiles. We demonstrate that baloxavir marboxil presents a similar safety and efficacy profile to those of drugs already used in the treatment of influenza. Further research on combination therapy is highly recommended and may have promising results.
Antiviral post-exposure prophylaxis with neuraminidase inhibitors can reduce the incidence of influenza and the risk of symptomatic influenza, but the efficacy of the other classes of antiviral remains unclear. To support an update of WHO influenza guidelines, this systematic review and network meta-analysis evaluated antiviral drugs for post-exposure prophylaxis of influenza. We systematically searched MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Cumulative Index to Nursing and Allied Health Literature, Global Health, Epistemonikos, and ClinicalTrials.gov for randomised controlled trials published up to Sept 20, 2023 that evaluated the efficacy and safety of antivirals compared with another antiviral or placebo or standard care for prevention of influenza. Pairs of reviewers independently screened studies, extracted data, and assessed the risk of bias. We performed network meta-analyses with frequentist random effects model and assessed the certainty of evidence using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach. The outcomes of interest were symptomatic or asymptomatic infection, admission to hospital, all-cause mortality, adverse events related to antivirals, and serious adverse events. This study is registered with PROSPERO, CRD42023466450. Of 11 845 records identified by our search, 33 trials of six antivirals (zanamivir, oseltamivir, laninamivir, baloxavir, amantadine, and rimantadine) that enrolled 19 096 individuals (mean age 6·75-81·15 years) were included in this systematic review and network meta-analysis. Most of the studies were rated as having a low risk of bias. Zanamivir, oseltamivir, laninamivir, and baloxavir probably achieve important reductions in symptomatic influenza in individuals at high risk of severe disease (zanamivir: risk ratio 0·35, 95% CI 0·25-0·50; oseltamivir: 0·40, 0·26-0·62; laninamivir: 0·43, 0·30-0·63; baloxavir: 0·43, 0·23-0·79; moderate certainty) when given promptly
The optimal antiviral drug for treatment of severe influenza remains unclear. To support updated WHO influenza clinical guidelines, this systematic review and network meta-analysis evaluated antivirals for treatment of patients with severe influenza. We systematically searched MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Cumulative Index to Nursing and Allied Health Literature, Global Health, Epistemonikos, and ClinicalTrials.gov for randomised controlled trials published up to Sept 20, 2023, that enrolled hospitalised patients with suspected or laboratory-confirmed influenza and compared direct-acting influenza antivirals against placebo, standard care, or another antiviral. Pairs of coauthors independently extracted data on study characteristics, patient characteristics, antiviral characteristics, and outcomes, with discrepancies resolved by discussion or by a third coauthor. Key outcomes of interest were time to alleviation of symptoms, duration of hospitalisation, admission to intensive care unit, progression to invasive mechanical ventilation, duration of mechanical ventilation, mortality, hospital discharge destination, emergence of antiviral resistance, adverse events, adverse events related to treatments, and serious adverse events. We conducted frequentist network meta-analyses to summarise the evidence and evaluated the certainty of evidence using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach. This study is registered with PROSPERO, CRD42023456650. Of 11 878 records identified by our search, eight trials with 1424 participants (mean age 36-60 years for trials that reported mean or median age; 43-78% male patients) were included in this systematic review, of which six were included in the network meta-analysis. The effects of oseltamivir, peramivir, or zanamivir on mortality compared with placebo or standard care without placebo for seasonal and zoonotic influenza were of very low certainty. Compa
Every year, more than one billion people around the world are infected with influenza, an acute infection of the respiratory tract. Influenza spreads from person to person through air, contaminated hands or objects. Antiviral and immunomodulatory drugs are available for treatment of patients and prophylaxis of exposed persons. Reverse transcription polymerase chain reaction (RT-PCR), nucleic acid amplification tests (NAATs) and rapid tests are available for the diagnosis of influenza. Objective The aim of this World Health Organization (WHO) guideline is to provide recommendations for the diagnosis, drug treatment and prophylaxis of influenza.This updated guideline has been developed in accordance with standards for trustworthy guidelines. The recommendations are based on systematic reviews on safety and effectiveness. They take into account the magnitude of benefits and harms of treatments, the reliability of the evidence, and the needs of patients and healthcare professionals.For non-severe influenza, there is a conditional recommendation to use baloxavir if the risk of severe illness is high. Antivirals are not recommended if the risk is low. There is also a strong recommendation against the use of antibiotics if bacterial co-infection is unlikely. Oseltamivir is conditionally recommended for severe influenza. Not recommended are peramivir and zanamivir, as well as macrolide antibiotics (in the absence of co-infection), mTOR inhibitors and plasma therapy, and corticosteroids. Baloxavir and oseltamivir are conditionally recommended for prophylaxis in asymptomatic persons who have been exposed to seasonal influenza viruses and would be at very high risk of becoming hospitalised. For zoonotic influenza, laninamivir and zanamivir are also conditionally recommended in addition to baloxavir and oseltamivir, regardless of individual risk. For diagnosis, the use of NAAT or digital immunoassay (DIA) for suspected non-severe influenza and nucleic acid amplification test (N
Influenza is an acute respiratory illness caused by the influenza A, B, and C viruses. It can occur in local outbreaks or seasonal epidemics, with possibility to spread worldwide in a pandemic when a novel strain with significant antigenic differences emerges. During the past years, several new drugs have become available, with different accessibility related to specific countries' approval. We have conducted a review of literature, analyzing the most recent data on efficacy and safety of drugs currently available to treat influenza, with a particular attention toward special populations. Efficacy and safety profile of neuraminidase inhibitors (oseltamivir, zanamivir, laninamivir, peramivir) and recently approved cap-dependent endonuclease inhibitor baloxavir marboxil are reported in literature, but still little information is available about special populations such as critically ill patients and patients with a history of chronic respiratory disease. Moreover, the emergence of strains with reduced or no susceptibility to current drugs is a matter of concern, suggesting the need of constant monitoring of viral variants.