For Patients and Caregivers

Single-dose XOFLUZA Has a Generally Well Tolerated Safety Profile1

Single-dose XOFLUZA had a similar adverse event (AE) rate as placebo—including in patients aged ≥12 years at high risk of developing complications from the flu.1

The below table shows AEs in Trials T0821, T0831, and T0832 that occurred in at least 1% of patients (aged ≥12 years) with acute uncomplicated influenza receiving either XOFLUZA or placebo.1*

Adverse Event XOFLUZA (n=1440) Placebo (n=1136)
Diarrhea 3% 4%
Bronchitis 3% 4%
Nausea 2% 3%
Sinusitis 2% 3%
Headache 1% 1%

*Based on combined data from 3 trials, a total of 1640 subjects received XOFLUZA: 1334 (81%) were adults (18-64 years of age), 209 (13%) were adults 65 years of age or older, and 97 (6%) were adolescents (12-17 years of age). Of these, 1440 subjects received XOFLUZA at the recommended dose.1

The below table shows the most frequently reported AEs in Trial CP40563 that occurred in ≥5% of patients (aged 5 to <12 years) with acute uncomplicated influenza in the XOFLUZA arm.1

Adverse Event XOFLUZA (n=79)
Vomiting 5%
Diarrhea 5%

There are limited safety data in patients 5 to <12 years at high risk of developing influenza complications.

Trial CP40563 was a randomized, double-blind, multicenter, active-controlled study designed to evaluate the safety, efficacy, and pharmacokinetics of a single oral dose of XOFLUZA compared with oseltamivir in pediatric subjects (including subjects aged 5 to <12 years) with influenza-like symptoms. A total of 118 subjects aged 5 to <12 years were randomized and received a single one-time oral dose of XOFLUZA (n=79) based on body weight (2 mg/kg for subjects weighing <20 kg or 40 mg for subjects weighing ≥20 kg) or oseltamivir (n=39) for 5 days (dose based on body weight). Of the 118 subjects 5 to <12 years of age in Trial CP40563, 15 subjects in the XOFLUZA arm and 4 subjects in the oseltamivir arm were at high risk of developing influenza complications. The primary objective was to compare the safety of a single one-time dose of XOFLUZA with 5 days of oseltamivir administered twice daily. Vomiting was reported in 18% of subjects in the oseltamivir arm.

A Single-Dose Flu Antiviral Rx for Post-Exposure Prophylaxis1

No serious treatment-related adverse events were reported.13

The safety profile of XOFLUZA was similar in patients aged 5 to <12 years and in patients aged 12 years and older.1

XOFLUZA® (baloxavir marboxil) Household Members
Single-dose XOFLUZA helps protect people who’ve been exposed to the flu by reducing their risk of infection.1

Trial T0834 was a phase 3, randomized, double-blind, multicenter, placebo-controlled trial designed to evaluate the efficacy of a single oral dose of XOFLUZA compared with placebo in the prevention of influenza in subjects who were household contacts of influenza-infected patients in Japan. Influenza-infected index patients were required to have onset of symptoms for ≤48 hours, and subjects (household contacts) were required to have lived with the influenza-infected index patient for ≥48 hours. A total of 715 subjects (XOFLUZA n=360, placebo n=355) aged 5 years and older were randomized and received a single oral dose of XOFLUZA according to body weight and age, or placebo, on Day 1. Subjects received a single dose of 40 mg or 80 mg of XOFLUZA according to body weight (20 kg to <80 kg or ≥80 kg, respectively). The primary efficacy endpoint was the proportion of household subjects who were infected with influenza virus and presented with fever and at least one respiratory symptom from Day 1 to Day 10. Influenza infection was confirmed by RT-PCR, fever was defined as a body temperature (axillary) ≥37.5°C, and respiratory symptoms were defined as having a symptom of “cough” or “nasal discharge/nasal congestion” with a severity of moderate or severe as assessed by the subject. In subjects that were 5 years of age and older, there was a statistically significant reduction in the proportion of household contacts (subjects) with laboratory-confirmed clinical influenza from 13% in the placebo group to 2% in the XOFLUZA group.1

XOFLUZA® (baloxavir marboxil) Clipboard Icon

Treats the Flu

See the clinical efficacy for single-dose XOFLUZA.1

Find out more
XOFLUZA® (baloxavir marboxil) Stop Replication Icon

Stops Viral Replication

Single-dose XOFLUZA stops the flu virus from replicating by targeting the flu at its source.1

XOFLUZA MOA

Important Safety Information & Indication

Indication

XOFLUZA is an influenza virus polymerase acidic (PA) endonuclease inhibitor indicated for:

  • Treatment of acute uncomplicated influenza in patients 5 years of age and 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.
  • Post-exposure prophylaxis (PEP) of influenza in patients 5 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 influenza virus strains when deciding whether to use XOFLUZA.

Important Safety Information

Contraindications
XOFLUZA is contraindicated in patients with a history of hypersensitivity to baloxavir marboxil or any of its ingredients. Serious allergic reactions have included anaphylaxis, angioedema, urticaria, and erythema multiforme.

 

Warnings and Precautions

Hypersensitivity: Cases of anaphylaxis, urticaria, angioedema, and erythema multiforme have been reported in postmarketing experience with XOFLUZA. Appropriate treatment should be instituted if an allergic-like reaction occurs or is suspected.
 

Increased Incidence of Treatment-Emergent Resistance in Patients Less Than 5 Years of Age: XOFLUZA is not indicated in patients less than 5 years of age due to increased incidence of treatment-emergent resistance in this age group. In clinical trials, the incidence of virus with treatment-emergent substitutions associated with reduced susceptibility to baloxavir (resistance) was higher in pediatric subjects younger than 5 years of age (40%, 38/96) than in pediatric subjects ≥5 years to <12 years of age (16%, 19/117) or subjects ≥12 years of age (7%, 60/842). The potential for transmission of resistant strains in the community has not been determined.
 

Risk of bacterial infections: There is no evidence of the efficacy of XOFLUZA in any illness caused by pathogens other than influenza viruses. Serious bacterial infections may begin with influenza-like symptoms or may coexist with, or occur as, a complication of influenza. XOFLUZA has not been shown to prevent such complications. Prescribers should be alert to potential secondary bacterial infections and treat them as appropriate.

Adverse Reactions

  • The most common adverse reactions (≥1%) in adult and adolescent patients (≥12 years of age) in clinical studies for acute uncomplicated influenza were diarrhea (3%), bronchitis (3%), nausea (2%), sinusitis (2%), and headache (1%).
  • The most frequently reported adverse reactions (≥5%) in pediatric patients (5 to <12 years of age) in clinical studies for acute uncomplicated influenza were vomiting (5%) and diarrhea (5%).
  • The safety profile reported in a clinical study for post-exposure prophylaxis was similar in pediatric patients ages 5 to <12 years old as that reported in adults and adolescents 12 years of age and older.

Drug Interactions

Polyvalent cations: Coadministration with polyvalent cation-containing products may decrease plasma concentrations of baloxavir, which may reduce XOFLUZA efficacy. Avoid coadministration of XOFLUZA with dairy products, calcium-fortified beverages, polyvalent cation-containing laxatives, antacids, or oral supplements (e.g., calcium, iron, magnesium, selenium, or zinc).

 

Vaccines: The concurrent use of XOFLUZA with intranasal live attenuated influenza vaccine (LAIV) has not been evaluated. Concurrent administration of antiviral drugs may inhibit viral replication of LAIV and, thereby, decrease the effectiveness of LAIV vaccination. Interactions between inactivated influenza vaccines and XOFLUZA have not been evaluated.


For additional Important Safety Information, please see the XOFLUZA full Prescribing Information.

You are encouraged to report side effects to Genentech by calling 1-888-835-2555 or to the FDA by visiting www.fda.gov/medwatch or calling 1-800-FDA-1088.

    • XOFLUZA. Prescribing information. Genentech USA, Inc.

      XOFLUZA. Prescribing information. Genentech USA, Inc.

    • Baker J, Block SL, Matharu B, et al. Baloxavir marboxil single-dose treatment in influenza-infected children: a randomized, double-blind, active controlled phase 3 safety and efficacy trial (miniSTONE-2). Pediatr Infect Dis J. 2020;39(8):700-705. doi:10.1097/INF.0000000000002747

      Baker J, Block SL, Matharu B, et al. Baloxavir marboxil single-dose treatment in influenza-infected children: a randomized, double-blind, active controlled phase 3 safety and efficacy trial (miniSTONE-2). Pediatr Infect Dis J. 2020;39(8):700-705. doi:10.1097/INF.0000000000002747

    • TAMIFLU. Prescribing information. Genentech USA, Inc.; 2019.

      TAMIFLU. Prescribing information. Genentech USA, Inc.; 2019.

    • Hayden FG, Sugaya N, Hirotsu N, et al; Baloxavir Marboxil Investigators Group. Baloxavir marboxil for uncomplicated influenza in adults and adolescents. N Engl J Med. 2018;379(10):913-923.

      Hayden FG, Sugaya N, Hirotsu N, et al; Baloxavir Marboxil Investigators Group. Baloxavir marboxil for uncomplicated influenza in adults and adolescents. N Engl J Med. 2018;379(10):913-923.

    • Ison MG, Portsmouth S, Yoshida Y, et al. Early treatment with baloxavir marboxil in high-risk adolescent and adult outpatients with uncomplicated influenza (CAPSTONE-2): a randomised, placebo-controlled, phase 3 trial. Lancet Infect Dis. 2020;20(10):1204-1214. doi:10.1016/S1473-3099(20)30004-9

      Ison MG, Portsmouth S, Yoshida Y, et al. Early treatment with baloxavir marboxil in high-risk adolescent and adult outpatients with uncomplicated influenza (CAPSTONE-2): a randomised, placebo-controlled, phase 3 trial. Lancet Infect Dis. 2020;20(10):1204-1214. doi:10.1016/S1473-3099(20)30004-9

    • Ison MG, Portsmouth S, Yoshida Y, et al. Early treatment with baloxavir marboxil in high-risk adolescent and adult outpatients with uncomplicated influenza (CAPSTONE-2): a randomised, placebo-controlled, phase 3 trial. Lancet Infect Dis. 2020;20(10)(suppl):1-63. doi:10.1016/S1473-3099(20)30004-9

      Ison MG, Portsmouth S, Yoshida Y, et al. Early treatment with baloxavir marboxil in high-risk adolescent and adult outpatients with uncomplicated influenza (CAPSTONE-2): a randomised, placebo-controlled, phase 3 trial. Lancet Infect Dis. 2020;20(10)(suppl):1-63. doi:10.1016/S1473-3099(20)30004-9

    • People at Increased Risk for Flu Complications. Centers for Disease Control and Prevention (CDC). Accessed January 30, 2025. https://www.cdc.gov/flu/highrisk/index.htm

      People at Increased Risk for Flu Complications. Centers for Disease Control and Prevention (CDC). Accessed January 30, 2025. https://www.cdc.gov/flu/highrisk/index.htm

    • National Diabetes Statistics Report. CDC. Accessed January 30, 2025. https://www.cdc.gov/diabetes/php/data-research/index.html

      National Diabetes Statistics Report. CDC. Accessed January 30, 2025. https://www.cdc.gov/diabetes/php/data-research/index.html

    • Most recent national asthma data. CDC. Accessed August 6, 2024. https://www.cdc.gov/asthma/most_recent_national_asthma_data.htm

      Most recent national asthma data. CDC. Accessed August 6, 2024. https://www.cdc.gov/asthma/most_recent_national_asthma_data.htm

    • About COPD. CDC. Accessed January 30, 2025. https://www.cdc.gov/copd/about/index.html

      About COPD. CDC. Accessed January 30, 2025. https://www.cdc.gov/copd/about/index.html

    • Heart disease. CDC. Accessed January 30, 2025. https://www.cdc.gov/nchs/fastats/heart-disease.htm

      Heart disease. CDC. Accessed January 30, 2025. https://www.cdc.gov/nchs/fastats/heart-disease.htm

    • Clinical signs and symptoms of influenza. CDC. Accessed January 30, 2025. https://www.cdc.gov/flu/hcp/clinical-signs/index.html

      Clinical signs and symptoms of influenza. CDC. Accessed January 30, 2025. https://www.cdc.gov/flu/hcp/clinical-signs/index.html

    • Ikematsu H, Hayden FG, Kawaguchi K, et al. Baloxavir marboxil for prophylaxis against influenza in household contacts. N Engl J Med. 2020;383(4):309-320. doi:10.1056/NEJMoa1915341

      Ikematsu H, Hayden FG, Kawaguchi K, et al. Baloxavir marboxil for prophylaxis against influenza in household contacts. N Engl J Med. 2020;383(4):309-320. doi:10.1056/NEJMoa1915341

    • 2023-2024 U.S. flu season: Preliminary in-season burden estimates. CDC. Accessed January 30, 2025. https://www.cdc.gov/flu-burden/php/data-vis/2023-2024.html

      2023-2024 U.S. flu season: Preliminary in-season burden estimates. CDC. Accessed January 30, 2025. https://www.cdc.gov/flu-burden/php/data-vis/2023-2024.html

    • 2023-2024 Flu Season. Accessed January 30 2025. https://www.cdc.gov/flu/season/2023-2024.html

      2023-2024 Flu Season. Accessed January 30 2025. https://www.cdc.gov/flu/season/2023-2024.html

    • Symptoms of COVID-19. CDC. Updated June 25, 2024. Accessed August 7, 2024. https://www.cdc.gov/covid/signs-symptoms/

      Symptoms of COVID-19. CDC. Updated June 25, 2024. Accessed August 7, 2024. https://www.cdc.gov/covid/signs-symptoms/

    • Allan GM, Arroll B. Prevention and treatment of the common cold: making sense of the evidence. CMAJ. 2014;186(3):190-199. doi:10.1503/cmaj.121442

      Allan GM, Arroll B. Prevention and treatment of the common cold: making sense of the evidence. CMAJ. 2014;186(3):190-199. doi:10.1503/cmaj.121442

    • Cold versus flu. CDC. Accessed January 30, 2025. https://www.cdc.gov/flu/symptoms/coldflu.htm

      Cold versus flu. CDC. Accessed January 30, 2025. https://www.cdc.gov/flu/symptoms/coldflu.htm

    • Is it flu, COVID-19, allergies or a cold? National Institutes of Health. https://newsinhealth.nih.gov/2022/01/it-flu-covid-19-allergies-or-cold. Accessed August 7, 2024.

      Is it flu, COVID-19, allergies or a cold? National Institutes of Health. https://newsinhealth.nih.gov/2022/01/it-flu-covid-19-allergies-or-cold. Accessed August 7, 2024.

    • About adenovirus. Symptoms. CDC. https://www.cdc.gov/adenovirus/about/index.html. Accessed August 7, 2024.

      About adenovirus. Symptoms. CDC. https://www.cdc.gov/adenovirus/about/index.html. Accessed August 7, 2024.

    • Is it a cold, the flu, or COVID-19? National Institute on Aging. https://www.nia.nih.gov/health/covid-19/it-cold-flu-or-covid-19. Accessed January 30, 2025.

      Is it a cold, the flu, or COVID-19? National Institute on Aging. https://www.nia.nih.gov/health/covid-19/it-cold-flu-or-covid-19. Accessed January 30, 2025.

    • COVID-19 Treatment Guidelines Panel. Coronavirus Disease 2019 (COVID-19) Treatment Guidelines. National Institutes of Health. Updated February 29, 2024. Accessed January 30, 2025. https://www.ncbi.nlm.nih.gov/books/NBK570371/pdf/Bookshelf_NBK570371.pdf

      COVID-19 Treatment Guidelines Panel. Coronavirus Disease 2019 (COVID-19) Treatment Guidelines. National Institutes of Health. Updated February 29, 2024. Accessed January 30, 2025. https://www.ncbi.nlm.nih.gov/books/NBK570371/pdf/Bookshelf_NBK570371.pdf

    • Influenza antiviral medications: summary for clinicians. CDC. Accessed July 24, 2024. https://www.cdc.gov/flu/professionals/antivirals/summary-clinicians.htm#Table1

      Influenza antiviral medications: summary for clinicians. CDC. Accessed July 24, 2024. https://www.cdc.gov/flu/professionals/antivirals/summary-clinicians.htm#Table1

    • Samji T. Influenza A: understanding the viral life cycle. Yale J Biol Med. 2009;82(4):153-159.

      Samji T. Influenza A: understanding the viral life cycle. Yale J Biol Med. 2009;82(4):153-159.

    • De Clercq E, Li G. Approved antiviral drugs over the past 50 years. Clin Microbiol Rev. 2016;29(3):695-747.

      De Clercq E, Li G. Approved antiviral drugs over the past 50 years. Clin Microbiol Rev. 2016;29(3):695-747.

    • Fiore AE, Fry A, Shay D, et al. Antiviral agents for the treatment and chemoprophylaxis of influenza—recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep. 2011;60(1):1-24.

      Fiore AE, Fry A, Shay D, et al. Antiviral agents for the treatment and chemoprophylaxis of influenza—recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep. 2011;60(1):1-24.

    • von Itzstein M. The war against influenza: discovery and development of sialidase inhibitors. Nat Rev Drug Discov. 2007;6(12):967-974. doi:10.1038/nrd2400

      von Itzstein M. The war against influenza: discovery and development of sialidase inhibitors. Nat Rev Drug Discov. 2007;6(12):967-974. doi:10.1038/nrd2400