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Influenza Virus Vaccine (Recombinant)

Medically reviewed by Drugs.com. Last updated on Jul 11, 2020.

Pronunciation

(in floo EN za VYE rus vak SEEN ree KOM be nant)

Index Terms

  • Flu Vaccine
  • Flublok Quadrivalent
  • Influenza Vaccine
  • Quadrivalent Recombinant Hemagglutinin (rHA) Vaccine
  • Recombinant Influenza Vaccine, Quadrivalent
  • RIV
  • RIV4

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Solution, Intramuscular [preservative free]:

Flublok: (0.5 mL [DSC]) [no egg protein]

Flublok: (0.5 mL [DSC]) [thimerosal free]

Solution Prefilled Syringe, Intramuscular [preservative free]:

Flublok Quadrivalent: 0.5 mL (0.5 mL) [egg free, latex free]

Flublok Quadrivalent: 0.5 mL (0.5 mL [DSC]) [egg free]

Brand Names: U.S.

  • Flublok Quadrivalent
  • Flublok [DSC]

Pharmacologic Category

  • Vaccine
  • Vaccine, Recombinant

Pharmacology

Promotes immunity to seasonal influenza virus by inducing specific antibody production. Preparations from previous seasons must not be used.

Onset of Action

Most adults have antibody protection within 2 weeks of vaccination (CDC/ACIP [Grohskopf 2020]).

Duration of Action

Vaccine effectiveness declines at a variable rate, depending on virus subtypes, patient age, and other confounding factors (CDC/ACIP [Grohskopf 2020]).

Use: Labeled Indications

Influenza disease prevention: Active immunization against influenza disease caused by influenza virus subtypes A and type B contained in the vaccine in persons ≥18 years of age

The Advisory Committee on Immunization Practices (ACIP) recommends routine annual vaccination with seasonal influenza vaccine for all persons ≥6 months who do not otherwise have contraindications to the vaccine. ACIP recommends use of any age and risk factor appropriate product and does not express any preference for an influenza vaccine product. Persons ≥18 years may receive vaccination with the recombinant influenza vaccine (RIV). In addition to RIV, other products are available for certain patient populations: Persons ≥6 months of age may receive the trivalent inactivated influenza vaccine or the quadrivalent inactivated influenza vaccine. Live attenuated influenza vaccine is also an option for persons 2 to 49 years of age (CDC/ACIP [Grohskopf 2020]).

When vaccine supply is limited, target groups for vaccination (those at higher risk of complications from influenza infection and their close contacts) include the following (CDC/ACIP [Grohskopf 2020]): Note: Only use RIV if appropriate.

• All infants and children 6 to 59 months of age

• Persons ≥50 years of age

• Infants, children, and adolescents (6 months to 18 years of age) who are receiving long-term aspirin or salicylate therapy, and therefore, may be at risk for developing Reye syndrome after influenza

• Residents of nursing homes and other long-term care facilities

• Patients with chronic pulmonary disorders (including asthma) or cardiovascular systems disorders (except isolated hypertension), renal, hepatic, neurologic, hematologic, or metabolic disorders (including diabetes mellitus)

• Persons who have immunosuppression due to any cause (including immunosuppression caused by medications or HIV)

• Infants, children, and adolescents (6 months to 18 years of age) who are receiving long-term aspirin or salicylate therapy, and therefore, may be at risk for developing Reye syndrome after influenza

• Women who are or will be pregnant during the influenza season

• Health care personnel, including students in these professions who will have contact with patients and other persons not directly involved in patient care but who may be exposed to infectious agents (eg, clerical, housekeeping, volunteers)

• Household contacts (including children) and caregivers of neonates, infants, and children <5 years (particularly neonates and infants <6 months) and adults ≥50 years

• Household contacts (including children) and caregivers of persons with medical conditions that put them at higher risk of severe complications from influenza infection

• American Indians/Alaska Natives

• Persons who are extremely obese (BMI ≥40)

Contraindications

Severe allergic reaction (eg, anaphylaxis) to any component of the vaccine

Dosing: Adult

Note: Immunization during coronavirus disease 2019 (COVID-19) pandemic: Routine vaccination should not be delayed because of the COVID-19 pandemic (CDC 2020; WHO 2020). In general, simultaneous administration of all vaccines for which a patient is eligible (according to current immunization schedules/guidelines) is recommended (ACIP [Ezeanolue 2020]). However, influenza vaccination in patients with suspected or confirmed COVID-19 infection (regardless of symptoms) should be postponed until the patient is no longer acutely ill and/or in isolation to avoid exposure to health care personnel and other patients (CDC/ACIP [Grohskopf 2020]; CDC 2020). Additional information is available from the CDC, the American Academy of Pediatrics, and the Immunization Action Coalition.

Note: Influenza seasons vary in the timing and duration from year to year. In general, vaccination should preferably occur in September and October (in the United States) to ensure optimal immunity prior to onset and for the full duration of influenza activity in the community. Early vaccination (in July or August) for an upcoming influenza season has been associated with suboptimal immunity before the end of an influenza season, particularly in older adults. Vaccination should continue throughout the influenza season as long as vaccine is available. The Centers for Disease Control and Prevention does not recommend revaccination later in the season for those persons who have already been fully vaccinated (CDC/ACIP [Grohskopf 2020]).

Immunization: IM: 0.5 mL/dose (1 per season).

Dosing: Geriatric

Refer to adult dosing.

Dosing: Pediatric

Note: Immunization during coronavirus disease 2019 (COVID-19) pandemic: Routine vaccination should not be delayed because of the COVID-19 pandemic (CDC 2020; WHO 2020). In general, simultaneous administration of all vaccines for which a patient is eligible (according to current immunization schedules/guidelines) is recommended (ACIP [Ezeanolue 2020]). However, influenza vaccination in patients with suspected or confirmed COVID-19 infection (regardless of symptoms) should be postponed until patient no longer acutely ill and to avoid exposure to health care personnel and other patients (CDC/ACIP [Grohskopf 2020]; CDC 2020). Additional information is available from the CDC, the American Academy of Pediatrics, and the Immunization Action Coalition.

Influenza seasons vary in their timing and duration from year to year. In general, vaccination should begin preferably in September and October (in US) to ensure optimal immunity prior to onset and for the full duration of influenza activity in the community. Early vaccination (in July or August) for an upcoming influenza season has been associated with suboptimal immunity before the end of an influenza season, particularly in older adults. Vaccination should continue throughout the influenza season as long as vaccine is available (CDC/ACIP [Grohskopf 2020]).

Immunization, annual: Adolescents ≥18 years: IM: 0.5 mL per dose as a single dose per season.

Administration

IM: For IM administration only. Gently invert the syringe prior to affixing the needle. Inspect for particulate matter and discoloration prior to administration. Avoid use if visible particles or discoloration are present in the solution after shaking. Adults should be vaccinated in the deltoid muscle. Do not inject into the gluteal region or areas where there may be a major nerve trunk. Do not mix with other vaccines or injections; separate needles and syringes should be used for each injection. To prevent syncope-related injuries, patients should be vaccinated while seated or lying down (ACIP [Ezeanolue 2020]). US law requires that the date of administration, the vaccine manufacturer, lot number of vaccine, Vaccine Information Statement (VIS) edition date and date it was provided, and the administering person's name, title, and address be recorded.

Unless otherwise indicated in product labeling, jet injectors should not be used to administer recombinant influenza vaccines. Currently, Afluria Quadrivalent inactivated influenza vaccine is the only influenza vaccine licensed in the United States with data about use with a jet-injector device.

Note: For patients at risk of hemorrhage following IM injection, the vaccine should be administered IM if, in the opinion of the physician familiar with the patient's bleeding risk, the vaccine can be administered by this route with reasonable safety. If the patient receives antihemophilia or other similar therapy, IM vaccination can be scheduled shortly after such therapy is administered. A fine needle (23 gauge or smaller) can be used for the vaccination and firm pressure applied to the site (without rubbing) for at least 2 minutes. The patient should be instructed concerning the risk of hematoma from the injection. Patients on anticoagulant therapy should be considered to have the same bleeding risks and treated as those with clotting-factor disorders (ACIP [Ezeanolue 2020]).

Storage

Store between 2°C to 8°C (36°F to 46°F). Protect from light. Do not freeze. Discard if frozen.

Adverse Reactions

>10%:

Local: Pain at injection site (19% to 37%), tenderness at injection site (34% to 48%)

Nervous system: Fatigue (12% to 17%), headache (13% to 20%)

Neuromuscular & skeletal: Myalgia (9% to 13%)

1% to 10%:

Gastrointestinal: Nausea (5% to 9%)

Local: Erythema at injection site (3% to 4%), swelling at injection site (≤5%, including firmness)

Nervous system: Chills (≤7%), shivering (≤7%)

Neuromuscular & skeletal: Arthralgia (8% to 10%)

Miscellaneous: Fever (≤2%)

Postmarketing:

Dermatologic: Urticaria

Hypersensitivity: Anaphylaxis, hypersensitivity reaction

Warnings/Precautions

Concerns related to adverse effects:

• Anaphylactoid/hypersensitivity reactions: Immediate treatment (including epinephrine 1 mg/mL) for anaphylactoid and/or hypersensitivity reactions should be available during vaccine use (ACIP [Ezeanolue 2020]).

• Shoulder injury related to vaccine administration: Vaccine administration that is too high on the upper arm may cause shoulder injury (eg, shoulder bursitis or tendinitis) resulting in shoulder pain and reduced range of motion following injection. Use proper injection technique for vaccines administered in the deltoid muscle (eg, injecting in the central, thickest part of the muscle) to reduce the risk of shoulder injury related to vaccine administration (Cross 2016; Foster 2013).

• Syncope: Syncope has been reported with use of injectable vaccines and may result in serious secondary injury (eg, skull fracture, cerebral hemorrhage); typically reported in adolescents and young adults and within 15 minutes after vaccination. Procedures should be in place to avoid injuries from falling and to restore cerebral perfusion if syncope occurs (ACIP [Ezeanolue 2020]).

Disease-related concerns:

• Acute illness: The decision to administer or delay vaccination because of current or recent febrile illness depends on the severity of symptoms and the etiology of the disease. Defer administration in patients with moderate or severe acute illness (with or without fever); vaccination should not be delayed for patients with mild acute illness (with or without fever) (ACIP [Ezeanolue 2020]).

• Bleeding disorders: Use with caution in patients with a history of bleeding disorders (including thrombocytopenia); bleeding/hematoma may occur from IM administration; if the patient receives antihemophilia or other similar therapy, IM injection can be scheduled shortly after such therapy is administered (ACIP [Ezeanolue 2020]).

• Guillain-Barré syndrome: Use with caution in patients with history of Guillain-Barré syndrome (GBS); patients with history of GBS have a greater likelihood of developing GBS than those without. As a precaution, the Advisory Committee on Immunization Practices (ACIP) recommends that patients with a history of GBS and who are at low risk for severe influenza complications and patients known to have experienced GBS within 6 weeks following previous vaccination should generally not be vaccinated (consider influenza antiviral chemoprophylaxis in these patients). The benefits of vaccination may outweigh the potential risks in persons with a history of GBS who are also at higher risk for severe complications of influenza. Influenza infection itself may cause GBS (CDC/ACIP [Grohskopf 2020]). Recent studies of patients who received the trivalent inactivated influenza vaccine or the monovalent H1N1 influenza vaccine have shown the risk of GBS is lower with vaccination than with influenza infection (Baxter 2013; Greene 2013; Kwong 2013).

Concurrent drug therapy issues:

• Anticoagulant therapy: Use with caution in patients receiving anticoagulant therapy; bleeding/hematoma may occur from IM administration (ACIP [Ezeanolue 2020]).

• Vaccines: In order to maximize vaccination rates, the ACIP recommends simultaneous administration (ie, >1 vaccine on the same day at different anatomic sites) of all age-appropriate vaccines (live or inactivated) for which a person is eligible at a single clinic visit, unless contraindications exist (ACIP [Ezeanolue 2020]).

Special populations:

• Altered immunocompetence: Consider deferring immunization during periods of severe immunosuppression (eg, patients receiving chemo/radiation therapy or other immunosuppressive therapy [including high-dose corticosteroid]); may have a reduced response to vaccination. Inactivated vaccine (inactivated influenza vaccine or recombinant influenza vaccine is preferred over live virus vaccine for household members, health care workers, and others coming in close contact with severely immunosuppressed persons requiring care in a protected environment (ACIP [Ezeanolue 2020]; CDC/ACIP [Grohskopf 2020]). Inactivated vaccines should be administered ≥2 weeks prior to planned immunosuppression when feasible; inactivated vaccines administered during chemotherapy should be readministered after immune competence is regained (ACIP [Ezeanolue 2020]; IDSA [Rubin 2014]).

• Pediatric: In a clinical trial of infants and children 6 months through 3 years of age, a decreased response to Flublok was reported compared to currently licensed US influenza vaccine for this population, suggesting that it would not be effective in children ≤3 years of age; safety and efficacy in older pediatric patients have not been established; use has not been studied.

Dosage form specific issues:

• Flublok Quadrivalent is an influenza vaccine produced using continuous insect cell lines. They are recombinant hemagglutinin (rHA) vaccines and do not use the influenza virus or eggs during the production process. ACIP states they may be used in persons with an egg allergy of any severity if otherwise appropriate (CDC/ACIP [Grohskopf 2020]).

Other warnings/precautions:

• Appropriate use: Use of this vaccine for specific medical and/or other indications (eg, immunocompromising conditions, hepatic or kidney disease, diabetes) is also addressed in the annual ACIP Recommended Immunization Schedules (refer to Centers for Disease Control and Prevention [CDC] schedule for detailed information). Specific recommendations for vaccination in immunocompromised patients with asplenia, cancer, HIV infection, cerebrospinal fluid leaks, cochlear implants, hematopoietic stem cell transplant (prior to or after), sickle cell disease, solid organ transplant (prior to or after), or those receiving immunosuppressive therapy for chronic conditions, as well as contacts of immunocompromised patients, are available from the Infectious Diseases Society of America (Rubin 2014).

• Effective immunity: Vaccination may not result in effective immunity in all patients. Response depends upon multiple factors (eg, type of vaccine, age of patient) and may be improved by administering the vaccine at the recommended dose, route, and interval. Vaccines may not be effective if administered during periods of altered immune competence (ACIP [Ezeanolue 2020]).

• Other influenza vaccines: Influenza vaccines from previous seasons must not be used. Vaccines formulated for the northern hemisphere may differ in composition from the southern hemisphere vaccine; consult CDC Yellow Book for more information regarding travel vaccines (ACIP [Ezeanolue 2020]; CDC/ACIP [Grohskopf 2020]).

Monitoring Parameters

Monitor for anaphylaxis and syncope for 15 minutes following administration (ACIP [Ezeanolue 2020]). If seizure-like activity associated with syncope occurs, maintain patient in supine or Trendelenburg position to reestablish adequate cerebral perfusion.

Reproductive Considerations

Influenza vaccination with any licensed, recommended, age-appropriate vaccine is recommended for all patients who may become pregnant during the influenza season and who do not otherwise have contraindications to the vaccine (CDC/ACIP [Grohskopf 2020]).

Pregnancy Considerations

Information specific to the use of recombinant influenza vaccine in pregnancy is limited (CDC/ACIP [Grohskopf 2020]).

Maternal vaccination provides passive immunization to the newborn and decreases the risk of hospitalization due to influenza in infants <6 months of age (ACOG 2018).

The risk for severe illness and complications from influenza infection is increased during pregnancy, particularly during the second and third trimesters (CDC/ACIP [Grohskopf 2020]). Pregnant patients infected with influenza have a higher risk than nonpregnant patients of progression to pneumonia, hospitalization, and ICU admission (ACOG 2018). Influenza vaccination decreases the risk of laboratory-confirmed influenza and hospitalization in pregnant patients (Thompson 2014; Thompson 2019)

The efficacy of influenza vaccination in pregnant patients is similar to nonpregnant adults. Influenza vaccination is recommended annually and should be given to pregnant patients even if they were vaccinated in a prior pregnancy (ACOG 2018). Influenza vaccination with any licensed, recommended, age-appropriate inactivated influenza vaccine or recombinant influenza vaccine is recommended for all patients who are pregnant during the influenza season and who do not otherwise have contraindications to the vaccine. Vaccination may be done at any time during pregnancy (CDC/ACIP [Grohskopf 2020])

Pregnant patients should observe the same precautions as nonpregnant patients to reduce the risk of exposure to influenza and other respiratory infections (CDC/HHS 2020). When vaccine supply is limited, focus on delivering the vaccine should be given to patients who are pregnant or will be pregnant during the flu season, as well as mothers of newborns and contacts or caregivers of children <5 years of age (CDC/ACIP [Grohskopf 2020]).

Data collection to monitor pregnancy and infant outcomes following exposure to influenza vaccine is ongoing. Persons exposed to this vaccine during pregnancy may contact the Flublok pregnancy registry at 1-800-822-2463.

Patient Education

What is this drug used for?

• It is used to prevent the flu.

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Injection site pain or irritation

• Headache

• Muscle pain

• Joint pain

• Loss of strength and energy

• Chills

• Nausea

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a limited summary of general information about the medicine's uses from the patient education leaflet and is not intended to be comprehensive. This limited summary does NOT include all information available about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not intended to provide medical advice, diagnosis or treatment and does not replace information you receive from the healthcare provider. For a more detailed summary of information about the risks and benefits of using this medicine, please speak with your healthcare provider and review the entire patient education leaflet.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.