U.S. flag An official website of the United States government

On Oct. 1, 2024, the FDA began implementing a reorganization impacting many parts of the agency. We are in the process of updating FDA.gov content to reflect these changes.

  1. Home
  2. Drugs
  3. Development & Approval Process | Drugs
  4. Drug Approvals and Databases
  5. Drug Trial Snapshot: XOFLUZA
  1. Drug Approvals and Databases

Drug Trial Snapshot: XOFLUZA

HOW TO USE THIS SNAPSHOT
The information provided in Snapshots highlights who participated in the clinical trials that supported the FDA approval of this drug, and whether there were differences among sex, race and age groups. The “MORE INFO” bar shows more detailed, technical content for each section. The Snapshot is intended as one tool for consumers to use when discussing the risks and benefits of the drugs.

LIMITATIONS OF THIS SNAPSHOT:
Do not rely on Snapshots to make decisions regarding medical care. Always speak to your health provider about the risks and benefits of a drug. Refer to the XOFLUZA Package Insert for complete information.

XOFLUZA (baloxavir marboxil)
zo-FLEW-zuh
Genentech USA, Inc.
Approval date: October 24, 2018


DRUG TRIALS SNAPSHOT SUMMARY:

What is the drug for?

XOFLUZA is a drug to treat the flu (influenza) in people 12 years of age and older who have had flu symptoms for no more than 48 hours.

How is this drug used?

XOFLUZA is a tablet taken as a single dose by mouth within 48 hours of flu symptoms.

The dose depends on the patient’s weight.

What are the benefits of this drug?

Patients treated with XOFLUZA had a shorter time to relieve symptoms compared with patients treated with placebo.

What are the benefits of this drug (results of trials used to assess efficacy)?

The figures below summarize efficacy results for the evaluated patients in Trials 1 and 2. The primary outcome was time to alleviation of symptoms.

Table 2. Time to Alleviation of Symptoms after Single Dose in Adult Subjects with Acute Uncomplicated Influenza in Trial 1 (Median Hours)

 

XOFLUZA 40 mg
(95% CI1)
N = 100

Placebo
(95% CI1)
N = 100

Adults (20 to 64 Years of Age)

50 hours2
(45, 64)

78 hours
(68, 89)

1CI: Confidence interval

2XOFLUZA treatment resulted in a statistically significant shorter time to alleviation of symptoms compared to placebo using the Gehan-Breslow’s generalized Wilcoxon test (p-value: 0.014, adjusted for multiplicity). The primary analysis using the Cox Proportional Hazards Model did not reach statistical significance (p-value: 0.165).

Table 3. Time to Alleviation of Symptoms after Single Dose in Subjects 12 Years of Age and Older with Acute Uncomplicated Influenza in Trial 2 (Median Hours)

 

XOFLUZA 40 mg or 80 mg1
(95% CI2)
N = 455

Placebo
(95% CI2)
N = 230

Subjects (≥ 12 Years of Age)

54 hours3
(50, 59)

80 hours
(73, 87)

1Dosing was based on weight. Subjects weighing < 80 kg received a single 40 mg dose and subjects ≥ 80 kg received a single 80 mg dose.

2CI: Confidence interval

3XOFLUZA treatment resulted in a statistically significant shorter time to alleviation of symptoms compared to placebo using the Peto-Prentice’s generalized Wilcoxon test (p-value: <0.001).

XOFLUZA Prescribing Information

Were there any differences in how well the drug worked in clinical trials among sex, race and age?

  • Sex: XOFLUZA worked similarly in males and females.
  • Race: XOFLUZA worked similarly among Whites and Asians. The number of patients in other races was limited; therefore, differences in how XOFLUZA worked among other races could not be determined.
  • Age: XOFLUZA worked similarly among patients 12 to 17 years of age and those 18 years of age and older.

Were there any differences in how well the drug worked in clinical trials among sex, race, and age groups?

The table below summarizes efficacy results by sex, race and age. The majority of patients were White and Asian, and the number of patients in all other races was limited. Therefore, racial subgroup differences were investigated between Whites and Asians.

Table 4. Median Time to Alleviation of Symptoms after Single Dose in Subjects 12 Years of Age and Older with Acute Uncomplicated Influenza in Trials 1 and 2

Time to Alleviation of Symptoms

Trial 1

Trial 2

 

XOFLUZA

Placebo

XOFLUZA

Placebo

Sex

  Female

N=40

N=39

N=224

N=110

  Median time in hours

54

93

63

87

  Male

N=60

N=61

N=231

N=120

  Median time in hours

48

69

48

74

Race

  White

N=0

N=0

N=85

N=40

  Median time in hours

--

--

93

126

  Asian

N=100

N=100

N=348

N=177

  Median time in hours

50

78

46

78

Age

  Adolescents (age 12 to 17)

N=0

N=0

N=63

N=27

  Median time in hours

--

--

54

93

  Adults (≥18 years of age)

N=100

N=100

N=392

N=203

  Median time in hours

50

78

54

79

FDA Review

What are the possible side effects?

The most common side effects are diarrhea, bronchitis, common cold (nasopharyngitis), headache, and nausea

What are the possible side effects (results of trials used to assess safety)?

The table below summarizes adverse reactions in patients with uncomplicated influenza in combined trials (safety population).

Table 5. Incidence of Adverse Events Occurring in Greater Than or Equal to 1% of Subjects Receiving XOFLUZA in the Acute Uncomplicated Influenza Trials

Adverse Event

XOFLUZA
(N = 710)

Placebo
(N = 409)

Diarrhea

3%

5%

Bronchitis

2%

4%

Nausea

1%

1%

Nasopharyngitis

1%

1%

Headache

1%

2%

XOFLUZA Prescribing Information

Were there any differences in side effects among sex, race and age?

  • Sex: The occurrence of side effects was similar in males and females.
  • Race: The occurrence of side effects was similar in Whites and Asians. The number of patients in other races was limited; therefore, differences in the occurrence of side effects among other races could not be determined.
  • Age: The occurrence of side effects among patients 12 to 17 years of age and those older than 18 years of age was similar.

Were there any differences in side effects of the clinical trials among sex, race, and age groups?

The table below summarizes the occurrence of the most common adverse reaction, diarrhea, by subgroup.

Table 6. Subgroup Analysis of Diarrhea (safety population)

Demographic Characteristic

XOFLUZA
n/N (%)

Placebo
n/N (%)

Sex

  Men

9/355 (3)

7/207 (3)

  Women

11/355 (3)

12/202 (6)

Race

   White

8/198 (4)

2/98 (2)

   Black or African American

0/40 (0)

1/24 (4)

   Asian

12/464 (3)

16/284 (6)

Other

0/8 (0)

0/3 (0)

Age Group

 < 18 years

3/76 (4)

2/41 (5)

  > 18 years

17/634 (3)

17/368 (5)

Clinical Trial Data

WHO WAS IN THE STUDIES?

Who participated in the clinical trials?

The FDA approved XOFLUZA based on evidence from two clinical trials (Trial 1/1518T0821 and Trial 2/NCT02954354) of 1119 patients with influenza-like illness. Trial 1 was conducted in Japan. Trial 2 was conducted in Japan and the United States.

Demographics of the patients who provided data for evaluation of benefits (efficacy population) are presented in Table 8, under the MORE INFO section.

The population that provided data for side effects of XOFLUZA (safety population) is presented below.

Figure 1 summarizes how many men and women were in the clinical trials used to evaluate safety.

Figure 1. Baseline Demographics by Sex (safety population)

FDA Review

Figure 2 summarizes the percentage of patients by race in the clinical trials used to evaluate safety.

Figure 2. Baseline Demographics by Race

FDA Review

Table 1. Demographics of Efficacy Trials by Race

Race

Number of Patients

Percentage of Patients

White

296

26%

Black or African American

64

6%

Asian

748

67%

Other

11

6%

Figure 3 summarizes the percentage of patients by age in the clinical trials used to evaluate safety.

Figure 3. Baseline Demographics by Age

Clinical Trial Data

Who participated in the trials

The table below summarizes the demographics of the safety population.

Table 7. Baseline Demographics of the Safety Population

Demographic Characteristic

Trial 1

Trial 2

TOTAL

XOFLUZA
(N = 100)

Placebo
(N = 100)

XOFLUZA
(N = 610)

Placebo
(N = 309)

(N = 1119)

Sex

  Men

60 (60)

61 (61)

295(48)

146 (47)

562 (50)

  Women

40 (40)

39 (39)

315 (52)

163 (53)

557 (50)

Race

  White

0 (0)

0 (0)

198 (33)

98 (32)

296 (26)

  Black or African American

0 (0)

0 (0)

40 (7)

24 (8)

64 (6)

  Asian

100 (100)

100 (100)

364 (60)

184 (60)

748 (67)

  Other

0 (0)

0 (0)

8 (1)

3 (1)

11 (1)

Age

>12 to < 17 years

0 (0)

0 (0)

76 (12)

41 (13)

117 (10)

  > 18 to < 29 years

27 (27)

28 (28)

184 (30)

88 (28)

327 (29)

  > 30 to < 39 years

30 (30)

28 (28)

138 (23)

68 (22)

264 (24)

  > 40 to < 49 years

28 (28)

32 (32)

123 (20)

58 (19)

241 (22)

  > 50 to < 59 years

11 (11)

9 (9)

74 (12)

43 (14)

137 (12)

> 60 to < 64 years

4 (4)

3 (3)

15 (2)

11 (4)

33 (3)

Age (years)

Mean (SD)

37.3 (10.6)

37.4 (10.6)

33.6 (13.1)

34.2 (13.9)

35.6 (12.1)

Median

38

37

33

33

35

Min, Max

20, 63

20, 64

12, 64

12, 64

12, 64

Ethnicity

  Hispanic

0 (0)

0 (0)

116 (19)

47 (15)

163 (15)

  Not Hispanic

100 (100)

100 (100)

494 (81)

262 (85)

956 (85)

Region

  Asia

100 (100)

100 (100)

355 (58%)

180 (58%)

735 (66)

  United States

0 (0)

0 (0)

255 (42%)

129 (42%)

384 (34)

Clinical Trial Data

The table below summarizes the demographics of the efficacy population.

Table 8. Baseline Demographics of the Efficacy Population

Demographic Characteristic

Trial 1

Trial 2

XOFLUZA
(N = 100)

Placebo
(N = 100)

XOFLUZA
(N = 456)

Placebo
(N = 231)

Sex

  Men

60 (60)

61 (61)

232(51)

120 (52)

  Women

40 (40)

39 (39)

224 (49)

111 (48)

Race

  White

0 (0)

0 (0)

85 (19)

40 (17)

  Black or African American

0 (0)

0 (0)

18 (4)

11 (5)

  Asian

100 (100)

100 (100)

349 (77)

178 (77)

  Other

0 (0)

0 (0)

4 (1)

2 (1)

Age

>12 to < 19 years

0 (0)

0 (0)

80 (18)

38 (17)

  > 20 to < 29 years

27 (27)

28 (28)

121 (27)

61 (26)

  > 30 to < 39 years

30 (30)

28 (28)

92 (20)

47 (20)

  > 40 to < 49 years

28 (28)

32 (32)

97 (21)

48 (21)

  > 50 to < 59 years

11 (11)

9 (9)

52 (11)

30 (13)

> 60 to < 64 years

4 (4)

3 (3)

14 (3)

7 (3)

Age (years)

Mean (SD)

37.3 (10.6)

37.4 (10.6)

33.5 (13.5)

33.9 (13.7)

Median

38

37

32

33

Min, Max

20, 63

20, 64

12, 64

12, 64

Ethnicity

  Hispanic

0 (0)

0 (0)

32 (7)

11 (5)

  Not Hispanic

100 (100)

100 (100)

424 (93)

220 (95)

Region

  Asia

100 (100)

100 (100)

343 (75)

175 (76)

  United States

0 (0)

0 (0)

113 (25)

56 (24)

Clinical Trial Data

How were the trials designed?

The benefit and side effects of XOFLUZA were evaluated in two clinical trials in adult and pediatric patients with uncomplicated influenza.

Trial 1 enrolled adult patients 20 to 64 years old who had symptoms of flu for no more than 48 hours. Patients were assigned to receive either a single dose of XOFLUZA or placebo by mouth. Neither the patients nor the health care providers knew which treatment was being given until after the trial was completed. The benefit of XOFLUZA was assessed based on the time patients reported all seven symptoms (cough, sore throat, nasal congestion, headache, fever, muscle pain, and tiredness) gone or mild for at least 21.5 hours, comparing the XOFLUZA and placebo groups.

Trial 2 enrolled adult and adolescent patients 12 to 64 years old who had symptoms of flu for not more than 48 hours. Adult patients were assigned to receive either XOFLUZA on Day 1 followed by placebo on Days 2 – 5, placebo as a twice daily dose by mouth for 5 days, or oseltamivir (a medication used to treat and prevent influenza) by mouth twice a day for 5 days. Neither the patients nor the health care providers knew which treatment was being given until after the trial was completed. The benefit of XOFLUZA was assessed based on the time patients reported all seven symptoms (cough, sore throat, nasal congestion, headache, fever, muscle pain, and tiredness) gone or mild for at least 21.5 hours, comparing the XOFLUZA and placebo groups.

How were the trials designed?

The efficacy and safety of XOFLUZA were evaluated in two randomized, double-blind clinical trials.

Trial 1 was a dose-finding trial in adult patients aged 20 to 64 years with uncomplicated influenza. Patients were randomized to receive a single oral dose of XOFLUZA or placebo. The primary efficacy endpoint was time to alleviation of symptoms defined as the time when all seven symptoms (cough, sore throat, nasal congestion, headache, fever, myalgia, and fatigue) had been assessed by patients as none or mild for a duration of at least 21.5 hours.

Trial 2 enrolled adult and adolescent patients 12 to 64 years of age weighing at least 40 kg. Adults were randomized to receive XOFLUZA or placebo as a single oral dose, or oseltamivir twice a day for 5 days. Patients in the XOFLUZA and placebo arms received a placebo for the duration of oseltamivir treatment. Adolescent patients (12 to less than 20 years of age) were randomized to receive XOFLUZA or placebo as a single oral dose. The primary efficacy endpoint was time to alleviation of symptoms defined as the time when all seven symptoms (cough, sore throat, nasal congestion, headache, fever, myalgia, and fatigue) had been assessed by patients as none or mild for a duration of at least 21.5 hours.

GLOSSARY

CLINICAL TRIAL: Voluntary research studies conducted in people and designed to answer specific questions about the safety or effectiveness of drugs, vaccines, other therapies, or new ways of using existing treatments.
COMPARATOR: A previously available treatment or placebo used in clinical trials that is compared to the actual drug being tested.
EFFICACY: How well the drug achieves the desired response when it is taken as described in a controlled clinical setting, such as during a clinical trial.
PLACEBO: An inactive substance or “sugar pill” that looks the same as, and is given the same way as, an active drug or treatment being tested. The effects of the active drug or treatment are compared to the effects of the placebo.
SUBGROUP: A subset of the population studied in a clinical trial. Demographic subsets include sex, race, and age groups.

 

 

Back to Drug Trials Snapshots

 

PRESCRIBING INFORMATION

Back to Top