Zanamivir

Generic name
Zanamivir
Brand name
ATC Code
J05AH01
Dosages
Side effects in children
Warnings & precautions in children
Contra-indications in children

Interactions
PK
Renal impairment
References

Pharmacokinetics in children

Inhalation
The pharmacokinetics of zanamivir were examined in an open-label study with single doses in 16 paediatric patients ranging in age from 6 to 12 years, after inhalation of dry powder (10 mg) with an inhaler (Diskhaler). The systemic exposure in children was comparable to that of adults on inhaling 10 mg of powder, but the variability was high in all age groups, even more so in the youngest children.

Intravenous

Age Dose N Cmax mean (mcg/ml) Cmax variation coefficient (%) T1/2 mean (hour)

T1/2 variatie coefficient (%)
6 mnd- 1 year 14 mg/kg 7 36,2 21 1,84 19
≥1-2 years 14 mg/kg 6 37,8 24 2,49 118
≥2-6 years 14 mg/kg 12 41,5 23 1,60 34
≥6-13 years 12 mg/kg 16 44,2 47 2,57 55
≥13-18 years 600 mg 13 34,5 27 2,06 47

 

dose recommendation of formulary compared to licensed use (on-label versus off-label)

No information is present at this moment.

Available formulations

No information is present at this moment.

Dosages

Seasonal prophylaxis during an influenza outbreak
  • Inhalation
    • 5 years up to 18 years
      • 10 mg/day in 1 dose
      • Duration of treatment:

        Maximum of 28 days.

    • 5 years up to 18 years
      [1]
      • 10 mg/day in 1 dose
      • Duration of treatment:

        Maximum of 28 days.
Prevention of influenza A and B (post exposure)
  • Inhalation
    • 5 years up to 18 years
      [1]
      • 10 mg/day in 1 dose
      • Duration of treatment:

        10 days

      • 1 dose is 2 inhalations of 5 mg
Treatment of complicated and potentially life-threatening influenza A or B virus infection
  • Intravenous
    • 6 months up to 6 years
      • 28 mg/kg/day in 2 doses.
    • 6 years up to 18 years
      • 24 mg/kg/day in 2 doses. Max: 1.200 mg/day.

Renal impaiment in children > 3 months

IN INTRAVENOUS ADMINISTRATION:

Children 6 months to 6 years and < 42.8 kg

  • 50-80 ml/min/1.73m2: loading dose 14 mg/kg, followed after 12 hours by maintenance dose 18,6 mg/kg/day in 2 doses;
  • 30-50 ml/min/1.73m2: loading dose 14 mg/kg, after 12 hours followed by maintenance dose 11,6 mg/kg/day in 2 doses;;
  • 15-30 ml/min/1.73m2: loading dose 14 mg/kg, after 24 hours followed by maintenance dose 7 mg/kg/day in 2 doses;
  • <15 ml/min/1.73m2: loading dose 14 mg/kg, after 48 hours followed by maintenance dose 2,8 mg/kg/day in 2 doses;

Children 6 months to 6 years and ≥ 42.8 kg

  • 50-80 ml/min/1.73m2: loading dose 600 mg, followed after 12 hours by maintenance dose 800 mg/day in 2 doses;
  •  30-50 ml/min/1.73m2: loading dose 600 mg, after 12 hours followed by maintenance dose 500 mg/day in 2 doses 
  • 15-30 ml/min/1.73m2: loading dose 600 mg, after 24 hours followed by maintenance dose 300 mg/day in 2 doses
  • <15 ml/min/1.73m2: loading dose 600 mg, after 48 hours followed by maintenance dose 120 mg/day in 2 doses.

Children 6 to18 years and < 50 kg

  • 50-80 ml/min/1.73m2: loading dose 12 mg/kg, followed after 12 hours by maintenance dose 16 mg/kg/day in 2 doses;
  • 30-50 ml/min/1.73m2: loading dose 12 mg/kg, after 12 hours followed by maintenance dose 10 mg/kg/day in 2 doses;;
  • 15-30 ml/min/1.73m2: loading dose 12 mg/kg, after 24 hours followed by maintenance dose 6 mg/kg/day in 2 doses;
  • <15 ml/min/1.73m2: loading dose 12 mg/kg, after 48 hours followed by maintenance dose 2,4 mg/kg/day in 2 doses;

Children 6 years and older and ≥ 50 kg

  •  50-80 ml/min/1.73m2: loading dose 600 mg, followed after 12 hours by maintenance dose 800 mg/day in 2 doses;
  •  30-50 ml/min/1.73m2: loading dose 600 mg, after 12 hours followed by maintenance dose 500 mg/day in 2 doses
  • 15-30 ml/min/1.73m2: loading dose 600 mg, after 24 hours followed by maintenance dose 300 mg/day in 2 doses.
  • < 15 ml/min/1.73m2: loading dose 600 mg, after 48 hours followed by maintenance dose 120 mg/day in 2 does

INHALED ADMINISTRATION:
No dose adjustment needed

Clinical consequences

With impaired renal function, AUC and half-life of zanamivir increase. This increases the risk of adverse reactions.

Clinical effects:
Parenteral: In a study with a single dose of 100 mg zanamivir intravenously, zanamivir AUC increased by 56% at ClCr 50-80 ml/min, 153% at 30-50 ml/min, and 427% at <30 ml/min.

By inhalation: In a study with intravenous administration of zanamivir, the pharmacokinetics of zanamivir appear to be altered with impaired renal function, but given the limited absorption after administration by inhalation and the fact that much higher exposures were well tolerated, this is not considered clinically relevant.

The complete list of all undesirable drug reactions can be found in the national Summary of Product Characteristics (SmPC) – click here

Side effects in children

Inhalation
Convulsions and psychiatric side effects, such as reduced level of consciousness, abnormal behaviour, hallucination and delirium.

Infusion
Side effect profile in children is similar to that in adults. 

The complete list of all contra-indications can be found in the national Summary of Product Characteristics (SmPC) – click here

Contra-indications in children

For the inhalation powder: milk protein allergy.

The complete list of all warnings and precautions can be found in the national Summary of Product Characteristics (SmPC) – click here

Warnings & precautions in children

Neuropsychiatric side effects have been reported during treatment with zanamivir in patients with influenza, particularly children and adolescents. Patients must therefore be monitored carefully for behavioural changes and the risks and benefits of continuing the treatment must be weighed up carefully for every patient.

Interactions

The complete list of all interactions can be found in the national Summary of Product Characteristics (SmPC) – click here

DIRECT ACTING ANTIVIRALS

This pages provides a list of drugs from the same ATC class for comparison. This does not necessarily mean that these drugs are interchangeable.

Nucleosides and nucleotides excl. reverse transcriptase inhibitors
J05AB01
J05AB12
J05AB06
J05AB16
J05AB04
J05AB11
J05AB14
Phosphonic acid derivatives
J05AD01
Protease inhibitors
J05AE08
J05AE10
J05AE07
J05AE02
J05AE04
J05AE03
J05AE01
Nucleoside and nucleotide reverse transcriptase inhibitors
J05AF06
J05AF02
J05AF09
J05AF10
J05AF05
J05AF04
J05AF07
J05AF13
J05AF13
J05AF01
Non-nucleoside reverse transcriptase inhibitors
J05AG06
J05AG03
J05AG04
J05AG01
J05AG05
Neuraminidase inhibitors
J05AH02
Antivirals for treatment of HIV infections, combinations
J05AR02
J05AR20
J05AR13
J05AR25
J05AR18
J05AR19
J05AR03
J05AR09
J05AR10
Other antivirals
J05AX28
J05AX12
J05AX07
J05AX09
J05AX08
J05AX24
ANTIVIRALS FOR TREATMENT OF HIV INFECTIONS, COMBINATIONS
J05AR02
J05AR20
J05AR13
J05AR25
J05AR18
J05AR19
J05AR03
J05AR09
J05AR10
Integrase inhibitors
J05AJ04
Antivirals for treatment of HCV infections
J05AP54
J05AP57
J05AP51
J05AP08
J05AP55

References

  1. GlaxoSmithKline BV, SmPC Relenza (RVG 24094) 16-04-2021, www.geneesmiddeleninformatiebank.nl
  2. GlaxoSmithKline Trading Services Limited, SmPC Dectova (EU/1/18/1349) Rev3; 23-03-2021, www.geneesmiddeleninformatiebank.nl
  3. NKFK Workinggroup Acute Kidney Impairment, Extrapolation of KNMP risk analysis "Impaired renal function" for adults to children, 20 Dec 2021

Changes

Therapeutic Drug Monitoring


Overdose