Effective Date

Date of Origin 

10/1/2022              

Relenza^®

(zanamivir)

Oral inhalation powder

1.Treatment of acute, uncomplicated influenza type A and B infections in patients aged 7 years and older who have been symptomatic for no more than 2 days.

2. Prophylaxis of influenza in patients aged 5 years and older.

Important limitations on use of zanamivir:

• Not a substitute for annual influenza vaccination
• Consider available information on influenza susceptibility patterns and treatment effects when deciding whether to use
• Not recommended for treatment or prophylaxis of influenza in:
  • Individuals with underlying airways disease
• Not proven effective for:  
  • Treatment in individuals with underlying airways disease.
  • Prophylaxis in nursing home residents.

1

Tamiflu^®ª

(oseltamivir)

Capsule

Oral suspension

1. Treatment of acute, uncomplicated influenza A and B in patients 2 weeks of age and older who have been symptomatic for no more than 48 hours.

2. Prophylaxis of influenza A and B in patients 1 year and older.

Important limitations of use:

• Not a substitute for annual influenza vaccination
• Consider available information on influenza susceptibility patterns and treatment effects when deciding whether to use

Not recommended for patients with end-stage renal disease not undergoing dialysis

1. Generic equivalent available

2

Xofluza^®

(baloxavir marboxil)

Tablet

Oral suspension

1. Treatment of acute uncomplicated influenza in patients 12 years of age or older who have been symptomatic for no more than 48 hours and who are:

• Otherwise healthy, or
• at high risk of developing influenza-related complications

2. Post-exposure prophylaxis of influenza in patients 12 years of age and older following contact with an individual who has influenza.

Limitations of use:  Influenza viruses change over time, and factors such as the virus type or subtype, emergence of resistance, or changes in viral virulence could diminish the clinical benefit of antiviral drugs.  Consider available information on drug susceptibility patterns for circulating virus strains when deciding whether to use Xofluza

4

Guidelines

Influenza

Antiviral treatment is recommended by the Centers for Disease Control and Prevention (CDC) as early as possible for any patient with confirmed or suspected influenza who: is hospitalized, has severe, complicated, or progressive illness, or is at higher risk for influenza complications. Antiviral treatment also can be considered for any previously healthy, symptomatic outpatient not at high risk for influenza complications, who is diagnosed with confirmed or suspected influenza, on the basis of clinical judgement, if treatment can be initiated within 48 hours of illness onset. Recommended duration for antiviral treatment is 5 days for oral oseltamivir or inhaled zanamivir. For the treatment of uncomplicated influenza with intravenous peramivir or oral baloxavir, a single dose is recommended. Longer daily dosing (oral oseltamivir or intravenous peramivir) can be considered for patients who remain severely ill after 5 days of treatment.

The CDC does not recommend widespread or routine use of antiviral medications for chemoprophylaxis except as one of multiple interventions to control institutional influenza outbreaks. Routine use of post-exposure chemoprophylaxis is not recommended; one reason for this is to avoid sub-therapeutic treatment dosing if infection is already established, although the possibility of whether antiviral resistant viruses could emerge is unknown. Antiviral medications can be considered for chemoprophylaxis to prevent influenza in certain situations, such as: prevention in people at high risk to influenza complications during the first two weeks following vaccination after exposure to a person with influenza, prevention for people at high risk for complications from influenza who cannot receive influenza vaccine due to a contraindication after exposure to a person with influenza, and prevention for people with severe immune deficiencies or others who might not respond to influenza vaccination, such as people receiving immunosuppressive medications, after exposure to a person with influenza. To be effective as chemoprophylaxis, an antiviral medication must be taken each day for the duration of potential exposure to a person with influenza and continued for 7 days after the last known exposure. For persons taking antiviral chemoprophylaxis after inactivated influenza vaccination, the recommended duration is until immunity after vaccination develops (antibody development after vaccination takes about two weeks in adults and can take longer in children depending on age and vaccination history).(3) For control of outbreaks in institutional settings (e.g., long-term care facilities for elderly people and children) and hospitals, CDC recommends antiviral chemoprophylaxis with oral oseltamivir or inhaled zanamivir for a minimum of 2 weeks and continuing up to 1 week after the last known case was identified. Antiviral chemoprophylaxis is recommended for all residents, including those who have received influenza vaccination. Baloxavir is approved for post-exposure prophylaxis (single-dose) of influenza in persons aged 12 years and older.

COVID-19 (SARS-CoV-2) and Influenza

During periods of community co-circulation of influenza viruses and SARS-CoV-2, empiric antiviral treatment of influenza is recommended as soon as possible for the following priority groups: hospitalized patients with respiratory illness, outpatients with severe, complicated, or progressive respiratory illness, and outpatients at higher risk for influenza complications who present with any acute respiratory illness symptoms (with or without fever). Patients who require hospitalization and are suspected of having either or both viral infections should receive influenza antiviral treatment with oseltamivir as soon as possible without waiting for influenza testing results. Treatment for influenza is the same for all patients regardless of SARS-CoV-2 coinfection. Clinicians can consider starting early (≤48 hours after illness onset) empiric antiviral treatment of non-high-risk outpatients with suspected influenza based upon clinical judgement. SARS-CoV-2 and other etiologies of influenza-like illness should also be considered.(5)

Safety

Zanamivir is contraindicated in patients with history of allergic reaction to any ingredient of Relenza, including milk proteins.(1)

1

Relenza prescribing information. GlaxoSmithKline. October 2021.

2

Tamiflu prescribing information. Gilead Sciences, Inc. August 2021.

3

Influenza Antiviral Medications: Summary for Clinicians.  Center for Disease Control and Prevention. Updated February 4, 2022. https://www.cdc.gov/flu/professionals/antivirals/summary-clinicians.htm.

4

Xofluza prescribing information. Genentech USA, Inc. September 2021.

5

Influenza and COVID-19. Center for Disease Control and Prevention. Updated October 27, 2021. https://www.covid19treatmentguidelines.nih.gov/special-populations/influenza/

125040602001

OSELTAMIVIR*oseltamivir phosphate cap  ; TAMIFLU*oseltamivir phosphate cap

30 MG ; 45 MG ; 75  ; 75 MG

20.0

CAPS

120

Days

125040800080

RELENZA*zanamivir aero powder breath activated

5 MG/BLISTER

40.0

BLSTRS

120

Days

12504060200110

TAMIFLU*Oseltamivir Phosphate Cap 30 MG (Base Equiv)

30 MG

40.0

CAPS

120

Days

12504060201910

TAMIFLU*Oseltamivir Phosphate For Susp 6 MG/ML (Base Equiv)

6 MG/ML

300.0

MLS

120

Days

1250202020B745

XOFLUZA*Baloxavir Marboxil Tab Therapy Pack 1 x 40 MG (40 MG Dose)

40 MG

2.0

TABS

120

Days

1250202020B760

XOFLUZA*Baloxavir Marboxil Tab Therapy Pack 1 x 80 MG (80 MG Dose)

80 MG

2.0

TABS

120

Days

1250202020B720

XOFLUZA*Baloxavir Marboxil Tab Therapy Pack 2 x 20 MG (40 MG Dose)

20 MG

4.0

TABS

120

Days

1250202020B735

XOFLUZA*Baloxavir Marboxil Tab Therapy Pack 2 x 40 MG (80 MG Dose)

40 MG

4.0

TABS

120

Days

OSELTAMIVIR*oseltamivir phosphate cap  ; TAMIFLU*oseltamivir phosphate cap

30 MG ; 45 MG ; 75  ; 75 MG

Blue Partner ; Commercial ; GenPlus ; Health Insurance Marketplace ; NetResults A Series ; SourceRx

RELENZA*zanamivir aero powder breath activated

5 MG/BLISTER

Blue Partner ; Commercial ; GenPlus ; Health Insurance Marketplace ; NetResults A Series ; SourceRx

TAMIFLU*Oseltamivir Phosphate Cap 30 MG (Base Equiv)

30 MG

Blue Partner ; Commercial ; GenPlus ; Health Insurance Marketplace ; NetResults A Series ; SourceRx

TAMIFLU*Oseltamivir Phosphate For Susp 6 MG/ML (Base Equiv)

6 MG/ML

Blue Partner ; Commercial ; GenPlus ; Health Insurance Marketplace ; NetResults A Series ; SourceRx

XOFLUZA*Baloxavir Marboxil Tab Therapy Pack 1 x 40 MG (40 MG Dose)

40 MG

Blue Partner ; Commercial ; GenPlus ; Health Insurance Marketplace ; NetResults A Series ; SourceRx

XOFLUZA*Baloxavir Marboxil Tab Therapy Pack 1 x 80 MG (80 MG Dose)

80 MG

Blue Partner ; Commercial ; GenPlus ; Health Insurance Marketplace ; NetResults A Series ; SourceRx

XOFLUZA*Baloxavir Marboxil Tab Therapy Pack 2 x 20 MG (40 MG Dose)

20 MG

Blue Partner ; Commercial ; GenPlus ; Health Insurance Marketplace ; NetResults A Series ; SourceRx

XOFLUZA*Baloxavir Marboxil Tab Therapy Pack 2 x 40 MG (80 MG Dose)

40 MG

Blue Partner ; Commercial ; GenPlus ; Health Insurance Marketplace ; NetResults A Series ; SourceRx

Quantities above the program quantity limit for the Target Agent(s) will be approved when BOTH of the following are met:

1. ONE of the following:
   1. The patient requires additional courses of therapy due to additional episodes of acute influenza infection OR
   2. The patient requires additional courses or increased duration of therapy for prophylaxis after exposure to an influenza infected person AND
2. ONE of the following:
   1. There is no shortage of the requested agent and ONE of the following:
      1. ALL of the following:
         1. The requested quantity (dose) is greater than the program quantity limit AND
         2. The requested quantity (dose) does NOT exceed the maximum FDA labeled dose for the requested indication AND
         3. The requested quantity (dose) cannot be achieved with a lower quantity of a higher strength that does not exceed the program quantity limit OR
      2. ALL of the following:
         1. The requested quantity (dose) is greater than the program quantity limit AND
         2. The requested quantity (dose) is greater than the maximum FDA labeled dose for the requested indication AND
         3. The prescriber has provided information in support of therapy with a higher dose for the requested indication OR
   2. There is a shortage of the requested agent and ONE of the following:
      1. ALL of the following:
         1. The requested quantity (dose) is greater than the program quantity limit AND
         2. The requested quantity (dose) does NOT exceed the maximum FDA labeled dose for the requested indication OR
      2. ALL of the following:
         1. The requested quantity (dose) is greater than the program quantity limit AND
         2. The requested quantity (dose) is greater than the maximum FDA labeled dose for the requested indication AND
         3. The prescriber has provided information in support of therapy with a higher dose for the requested indication

Compendia Allowed: National Comprehensive Cancer Network (NCCN) Compendium™ level of evidence 1, or 2A; American Hospital Formulary Service (AHFS); Truven Micromedex/DrugDex – Class I or IIa recommendation, Clinical Pharmacology or a phase 3 clinical trial OR the prescriber has submitted a clinical study or additional documentation published in a major peer-reviewed medical journal supporting the requested therapeutic use

Length of Approval:  4 months