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  5. Drug Trials Snapshots: VIBERZI
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Drug Trials Snapshots: VIBERZI

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 VIBERZI Prescribing Information for complete information.

VIBERZI (eluxadoline)
(vye BER zee)
Forest Pharmaceuticals, Inc.
Approval date: May 27, 2015


DRUG TRIALS SNAPSHOT SUMMARY:

What is the drug for?

VIBERZI is a treatment for adults with a disease of the gut called irritable bowel syndrome with diarrhea, commonly referred to as IBS-D.

How is this drug used?

VIBERZI is a tablet taken by mouth two times each day with food.

What are the benefits of this drug?

VIBERZI decreases abdominal pain and makes stool less watery.

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

The table below summarizes the composite efficacy endpoint for each trial. This was based on the simultaneous improvement of Worst Abdominal Pain (WAP) by ≥30% and Bristol Stool Score (BSS) < 5="" on="" the="" same="" day="" for="" ≥50%="" of="" days="" over="" the="" 12="" weeks="" interval="" for="" viberzi="" 100="" mg="" and="" 75="" mg="" in="" comparison="" to="">

Table 2. Efficacy Results in Trials 1 and 2

  Trial 1 Trial 2
Composite response* over 12 weeks VIBERZI
100 mg
n=426
VIBERZI
75 mg
n=427
Placebo
n=427
VIBERZI
100 mg
n=382
VIBERZI
75 mg
n=381
Placebo
n=382
Responder rates (%) 25

 

24

 

17

 

30

 

29

 

16

 

Treatment difference (%) 8**

 

7****

 

 

13***

 

13***

 

 

95% CI (%) (2.6,13.5)

 

(1.4,12.2)

 

 

(7.5,19.2)

 

(6.8, 18,5)

 

 

*Simultaneous improvement of Worst Abdominal Pain by ≥30% and Bristol Stool Score < 5="" on="" the="" same="" day="" for="" ≥50%="" of="" days="" over="" the="">
** p<>
*** p<>
****p<>

Source: Modified from VIBERZI Prescribing information, Section 14, Table 4

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

Subgroup analyses were conducted for sex, race and age.

  • Sex: The majority of patients in the trials were women. VIBERZI was similarly effective in men and women.
  • Race: The majority of patients in the trials were white. Differences in response to VIBERZI between races could not be determined.
  • Age: The majority of patients in the trials were less than 65 years of age. VIBERZI was similarly effective in all age groups studied.

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

The tables below summarize the results for the primary endpoint in the trial by subgroup.

Table 3. Subgroup Analysis of Primary Endpoint-Trial 1 (ITT population)

Subgroup VIBERZI 100 mg VIBERZI 75 mg Placebo
x (%) Total, n x (%) Total, n x (%) Total, n
Overall Response/All patients 107 (25) 426 102 (24) 427 73 (17) 427
Sex
Male 31 (22) 143 39 (26) 151 20 (13) 150
Female 73 (27) 283 63 (23) 276 53 (19) 277
Age Group
<65> 95 (24) 391 88 (22) 398 66 (18) 376
>= 65 years 12 (34) 35 14 (48) 29 7 (14) 51
Race
White 94 (26) 368 90 (24) 372 67 (18) 370
Black or African American 9 (20) 46 11 (24) 46 6 (13) 46
Other 2 (20) 10 1 (11) 9 0 11
Ethnicity 
Hispanic or Latino 22 (19) 117 18 (15) 119 19 (15) 125
Not Hispanic or Latino 83 (27) 307 84 (27) 308 54 (18) 302
Region
United States 103 (26) 404 94 (23) 403 65 (16) 405
Non US 4 (18) 22 8 (33) 24 8 (36) 22

Source: Company Clinical Trial Data

Table 4. Subgroup Analysis of Primary Endpoint-Trial 2 (ITT population)

Subgroup VIBERZI 100 mg VIBERZI 75 mg Placebo
x (%) Total, n x (%) Total, n x (%) Total, n
Overall Response/All patients 113 (30) 382 110 (29) 381 62 (16) 382
Sex
Male 40 (32) 126 35 (29) 120 23 (17) 132
Female 73 (29) 256 75 (29) 261 39 (16) 250
Age Group
<65> 99 (29) 343 94 (27) 345 57(17) 331
>= 65 years 14 (36) 39 16 (44) 36 5 (10) 51
Race
White 99 (31) 318 100 (31) 327 53 (16) 329
Black or African American 12 (24) 50 10 (22) 46 7 (16) 43
Other 2 (14) 14 0 8 2 (20) 10
Ethnicity
Hispanic or Latino 30 (30) 99 35 (36) 98 17 (17) 101
Not Hispanic or Latino 83 (29) 283 75 (27) 283 45 (16) 281
Region
United States 106 (29) 365 107 (29) 366 61 (17) 366
Non US 7 (41) 17 3 (20) 15 1 (6) 16

Source: Company Clinical Trial data

What are the possible side effects?

The most common side effects of VIBERZI are constipation, nausea and belly pain.

The most serious known risk is too much contraction of a small muscle in the gut (called the sphincter of Oddi) that controls the flow of juices into the small intestine from the liver and pancreas to help with food digestion. Contraction of this muscle can cause sudden pain in the belly and lead to abnormal results from liver and pancreas tests. These abnormal results may indicate damage to the liver and swelling of the pancreas (called pancreatitis).

Because of these side effects, VIBERZI should not be used in patients who have or have had problems with their sphincter of Oddi, pancreatitis, severe liver problems, severe constipation, or possible blockage of their gut. VIBERZI should also not be used in patients who drink more than three alcoholic beverages per day.

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

The table below summarizes adverse reactions for the Safety population, which includes any patient who received at least one dose of trial drug. The Safety population is a pooled population of two Phase 3 trials and one additional Phase 2 trial.

Table 5. Common* Adverse Reactions in the Pooled Trials (Safety population)

Adverse Reactions VIBERZI 100 mg
(n= 1032)
%
VIBERZI 75 mg
(n=807)
%
Placebo
(n=975)
%
Constipation 8 7 3
Nausea 7 8 5
Abdominal Pain** 7 6 4
Upper Respiratory Tract Infection 5 3 4
Vomiting 4 4 1
Nasopharyngitis 3 4 3
Abdominal Distention 3 3 2
Bronchitis 3 3 2
Dizziness 3 3 2
Flatulence 3 3 2
Rash*** 3 3 2
Increased ALT 3 2 1
Fatigue 2 3 2
Viral gastroenteritis 1 3 2

*Reported in > 2% of VIBERZI-treated patients at either dose and at an incidence greater than in placebo-treated patients

**"Abdominal Pain" term includes: abdominal pain, abdominal pain lower, and abdominal pain upper
*** "Rash" term includes: dermatitis, dermatitis allergic, rash, rash erythematous, rash generalized, rash maculo-papular, rash papular, rash pruritic, urticaria, and idiopathic urticaria
Source: VIBERZI Prescribing Information, Section 14, Table 1

 

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

Subgroup analyses were conducted for sex, race, and age.

  • Sex: The majority of patients in the trials were women. The risk of overall side effects was similar in men and women.
  • Race: The majority of patients in the trials were white. Differences in side effects among races could not be determined.
  • Age: Overall side effects were seen more often in patients 65 years of age and above compared to those below the age of 65. Side effects in the gut and certain side effects—called serious adverse events1 --were also seen more often in patients age 65 and above compared to those below the age of 65.

1Serious adverse event was defined as any event that resulted in one of the following: death, life-threatening event, required hospitalization or extended a current hospital stay, persistent or significant disability/incapacity, or congenital anomaly or birth defect

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

The Prescribing Information for VIBERZI (Section 8.5) states that a higher proportion of elderly patients than younger patients experienced adverse reactions, serious adverse reactions, and gastrointestinal adverse reaction.

The table below summarizes adverse events in the pooled trials (Safety population) by subgroups.

Table 6. Subgroup Analysis of all Adverse Events While on Treatment (Safety Population)

Subgroup VIBERZI 100 mg VIBERZI 75 mg Placebo
x (%) Total, n x (%) Total, n x (%) Total, n
Any TEAEs* 575 (56) 1032 486 (60) 807 533 (55) 975
Sex
Male 177 (52) 343 139 (52) 270 156 (47) 333
Female 398 (58) 689 347 (65) 537 377 (59) 642
Age Group
<65> 526 (55) 957 443 (60) 742 465 (53) 872
>=65 years 49 (65) 75 43 (66) 65 68 (66) 103
Race
White 502 (57) 875 427 (61) 698 481 (57) 847
Black or African American 57 (45) 126 46 (50) 92 40 (38) 105
Other 16 (52) 31 13 (77) 17 12 (52) 23

*TEAEs=treatment-emergent adverse events
Source: Company Clinical Trial Data

The table below summarizes gastrointestinal adverse events in the pooled trials (Safety population) by subgroups.

Table 7. Subgroup Analysis of Gastrointestinal AEs while on Treatment (Safety Population)

Subgroup VIBERZI 100 mg VIBERZI 75 mg Placebo
x (%) Total, n x (%) Total, n x (%) Total, n
Any GI AEs* 273 (27) 1032 242 (30) 807 185 (19) 975
Sex
Male 78 (23) 343 61 (23) 270 52 (16) 333
Female 195 (28) 689 181 (34) 537 133 (21) 642
Age Group
<65> 241 (25) 957 220 (30) 742 156 (18) 872
>=65 years 32 (43) 75 22 (34) 65 29 (28) 103
Race
White 237 (27) 875 219 (31) 698 165 (20) 847
Black or African American 24 (19) 126 17 (19) 92 15 (14) 105
Other 12 (39) 31 6 (35) 17 5 (22) 23

*GI AEs= Gastrointestinal adverse events
Source: Company Clinical Trial Data

WHO WAS IN THE STUDIES?

Who participated in the clinical trials?

The FDA approved VIBERZI based on evidence from two clinical trials of 2425 patients with IBS-D. The trials were conducted at 556 sites in the United States, Canada, and United Kingdom.

Figure 1 summarizes how many men and women were enrolled in the clinical trials used to evaluate the benefit of VIBERZI.

Figure 1. Baseline Demographics by Sex

Pie chart summarizing how many men and women were enrolled in the clinical trials used to evaluate efficacy of the drug VIBERZI.  In total, 822 men (34%) and 1603 women (66%) participated in the clinical trials used to evaluate efficacy of the drug VIBERZI

Source: Company Clinical Trial Data

Figure 2 and Table 1 summarize the percentage of patients by race enrolled in the clinical trials used to evaluate benefit.

Figure 2. Baseline Demographics by Race

Baseline Demographics by Race Viberzi

Source: Company Clinical Trial Data

Table 1. Demographics of Efficacy Trials by Race

Race Number of Patients Percentage
White 2084 85.9%
Black or African American 279 11.5%
Asian 25 1.0%
American Indian or Alaska Native 11 0.5%
Native Hawaiian or Other Pacific Islander 4 0.2%
Other 22 0.9%

Source: Company Clinical Trial Data

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

Figure 3. Baseline Demographics by Age

Pie chart summarizing how many individuals of certain age groups were enrolled in the VIBERZI clinical trial.  In total, 2184 were less than 65 years (90%) and 241 were 65 and older (10%)

Source: Company Clinical Trial Data

Who participated in the trials?

The tables below summarize baseline demographics for the efficacy (ITT) and safety populations.

Table 8. Demographic and Baseline Characteristics (ITT Population)

Demographic Parameters Trial 1 Trial 2 Total
(N=2425)
n (%)
VIBERZI
100 mg
(N=426)
n (%)
VIBERZI
75 mg
(N=427)
n (%)
Placebo
(N=427)
n (%)
VIBERZI
100 mg
(N=382)
n (%)
VIBERZI
75 mg
(N=381)
n (%)
Placebo
(N=382)
n (%)
Sex
Male 143 (34) 151 (35) 150 (35) 126 (33) 120 (32) 132 (35) 822 (34)
Female 283 (66) 276 (65) 277 (65) 256 (67) 261 (68) 250 (65) 1603 (66)
Age
Mean years (SD) 44.4 (13.91) 44.5 (13.20) 45.8 (14.10) 45.7 (13.32) 45.0 (13.17) 47.1 (13.82) 45.4 (13.62)
Median (years) 45.0 44.0 45.0 45.0 45.0 47.5 45.0
Min, Max (years) 18, 79 18, 80 18, 79 19, 75 18, 77 19, 77 18, 80
Age Group
<65> 391 (92) 398 (93) 376 (88) 343 (90) 345 (91) 331 (87) 2184 (90)
>=65 years 35 (8) 29 (7) 51 (12) 39 (10) 36 (9) 51 (13) 241 (10)
Race
White 368 (86) 372 (87) 370 (87) 318 (83) 327 (86) 329 (86) 2084 (86)
Black or African American 48 (11) 46 (11) 46 (11) 50 (13) 46 (12) 43 (11) 279 (12)
Asian 3 (1) 3 (1) 4 (1) 7 (2) 2 (<> 6 (2) 25 (1)
American Indian or Alaska Native 2 (1) 1 (<> 1 (<> 3 (1) 3 (1) 1 (<> 11 (<>
Native Hawaiian or Other Pacific Islander 1 (<> 0 0 1 (<> 0 2 (1) 4 (<>
Other 4 (1) 5 (1) 6 (1) 3 (1) 3 (1) 1 (<> 22 (1)
Ethnicity
Hispanic or Latino 117 (28) 119 (28) 125 (29) 99 (26) 98 (26) 101 (26) 659 (27)
Not Hispanic or Latino 309 (72) 308 (72) 302 (71) 283 (74) 283 (74) 281 (74) 1766 (73)
Region
United States 404 (95) 403 (94) 405 (95) 365 (96) 366 (96) 366 (96) 2309 (95)
Non US 22 (5) 24 (6) 22 (5) 17 (4) 15 (4) 16 (4) 116 (5)

Source: Company Clinical Trial Data

Table 9. Demographic and Baseline Characteristics (Safety Population)

Demographic Parameters VIBERZI
100 mg
(N=1032)   
 n (%)
VIBERZI
75mg
(N=807)
n (%)
Placebo
(N=975)
n (%)
Total
(N=2814)
n (%)
Sex
Male 343 (33) 270 (34) 333 (34) 946 (34)
Female 689 (67) 537 (66) 642 (66) 1868 (66)
Age
Mean years (SD) 44.8 (13.13) 44.8 (13.17) 46.0 (13.72) 45.22 (13.36)
Median (years) 45.0 44.0 46.0 45.0
Min, Max (years) 18, 79 18, 80 18, 79 18, 80
Age Group
<65> 957 (93) 742 (93) 872 (89) 2571 (91)
>=65 years 75 (7) 65 (8) 103 (11) 243 (9)
Race
White 875 (85) 698 (87) 847 (87) 2420 (86)
Black or African     
American
126 (12) 92 (11) 105 (11) 323 (11)
Asian 13 (1) 5 (1) 12 (1) 30 (1)
American Indian or                  
Alaska Native
5 (1) 4 (<> 2 (<> 11 (<>
Native Hawaiian or
Other Pacific Islander
2 (<> 0 2 (<> 4 (<>
Other 11 (1) 8 (1) 7 (1) 26 (1)
Ethnicity
Hispanic or Latino 261 (25) 214 (27) 251 (26) 726 (26)
Not Hispanic or Latino 771 (71) 593 (73) 724 (74) 2088 (74)
Region
United States 991 (96) 768 (95) 937 (96) 2696 (96)
Non US 41 (4) 39 (5) 38 (4) 118 (4)

Source: Company Clinical Trial Data

How were the trials designed?

There were two trials that evaluated the benefit and side effects of VIBERZI. In each trial, patients were randomly assigned to receive either VIBERZI 100 mg or VIBERZI 75 mg or placebo two times daily for at least 26 weeks. Neither the patients nor the health care providers knew which treatment was being given until after the trials were completed.

The trials measured improvements at 12 weeks in abdominal pain and watery stool and compared VIBERZI to placebo.

How were the trials designed?

Two randomized, multi-center, double-blind, placebo-controlled trials were conducted to assess the efficacy and safety of 12 weeks of twice daily treatment with VIBERZI 100 mg or VIBERZI 75 mg in comparison to placebo in patients with irritable bowel syndrome with diarrhea.

The efficacy was assessed using a composite endpoint which included improvement in the daily worst abdominal pain score by ≥30% as compared to the baseline weekly average AND a reduction in the Bristol Stool Scale to <5 on="" at="" least="" 50%="" of="" the="" days="" within="" a="" 12-week="" time="">

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.

PRESCRIBING INFORMATION

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