Drug Trials Snapshots: FILSUVEZ

HOW TO USE THIS SNAPSHOT
The information provided in Snapshots highlights who participated in the key clinical trials that supported the original FDA approval of this drug, and whether there were differences among sex, race, age, and ethnic 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 healthcare provider about the benefits and risks of a drug.

Some of the information in this Snapshot is for presentation purposes and does not represent the approved conditions of use of this drug. Refer to the FILSUVEZ Prescribing Information for all of the approved conditions of use of this drug (e.g., indication(s), population(s), dosing regimen(s), safety information).

Snapshots are limited to the information available at the time of the original approval of the drug and do not provide information on who participated in clinical trials that supported later approvals for additional uses of the drug (if applicable).

FILSUVEZ (birch triterpenes) topical gel
fill-sue-vez
Amryt
Original Approval date: December 18, 2023

---

DRUG TRIALS SNAPSHOT SUMMARY:

What is the drug for?

FILSUVEZ is for the treatment of wounds associated with dystrophic and junctional epidermolysis bullosa (EB) in adult and pediatric patients 6 months of age and older.

How is this drug used?

FILSUVEZ is a topical gel applied to cleansed wounds with wound dressing changes until the wound is healed.

Who participated in the clinical trials?

The FDA approved FILSUVEZ based on evidence from a clinical trial of 223 patients with dystrophic and junctional EB. The trial was conducted at 49 sites in 26 countries including Argentina, Australia, Austria, Belgium, Brazil, Chile, Colombia, Croatia, Czech Republic, Denmark, France, Germany, Greece, Hong Kong, Hungary, Ireland, Israel, Italy, Romania, Russia, Serbia, Singapore, Spain, Switzerland, the United Kingdom, and the United States. There were 14 subjects enrolled in the United States and 209 subjects were enrolled outside the United States.

How were the trials designed?

The efficacy and safety of FILSUVEZ for the treatment of partial-thickness wounds associated with inherited EB was evaluated in a randomized, double-blind, placebo-controlled trial in adults and pediatric subjects 6 months of age and older with dystrophic EB (DEB) and junctional EB (JEB). The primary endpoint was the proportion of subjects with first complete closure of the target wound by Day 45 of the 90-day double-blind phase of the study, based on clinical assessment by the investigator.

How were the trials designed?

The efficacy and safety of FILSUVEZ for the treatment of partial-thickness wounds associated with inherited EB was evaluated in a randomized, double-blind, placebo-controlled trial in adults and pediatric subjects 6 months of age and older with DEB and JEB. Subjects were randomized 1:1 to receive FILSUVEZ (N=109) or placebo topical gel (N=114) and instructed to apply approximately 1 mm (0.04 inch) of the investigational product to all their wounds at each dressing change (every one to four days) for 90 days. At randomization, one wound was selected by the investigator as the target wound for the evaluation of the primary efficacy endpoint. The target wound was defined as a partial-thickness wound of 10 to 50 cm2 in surface area and present for 21 days to 9 months prior to screening.

DEMOGRAPHICS SNAPSHOT

Figure 1 summarizes how many male and female patients were enrolled in the clinical trial used to evaluate the efficacy of FILSUVEZ.

Figure 1. Baseline Demographics by Sex

Source: Adapted from FDA Review

Figure 2 summarizes the percentage of patients by race enrolled in the clinical trial used to evaluate the efficacy of FILSUVEZ.

Figure 2. Baseline Demographics by Race

Source: Adapted from FDA Review

Figure 3 summarizes the percentage of patients by age enrolled in the clinical trial used to evaluate the efficacy of FILSUVEZ.

Figure 3. Baseline Demographics by Age

 

Source: Adapted from FDA Review

Figure 4 summarizes the percentage of patients by ethnicity enrolled in the clinical trial used to evaluate the efficacy of FILSUVEZ.

Figure 4. Baseline Demographics by Ethnicity

Source: Adapted from FDA Review

Who participated in the trials?

Table 1. Baseline Demographics of Efficacy Trials by Age, Race, Sex, and Ethnicity

Demographic	FILSUVEZ N=109 n (%)	Placebo N=114 n (%)	Total N=223 n (%)
Sex
Male	68 (62)	66 (58)	134 (60)
Female	41 (38)	48 (42)	89 (40)
Age group, years
<4	7 (6)	10 (9)	17 (8)
ࣙ    4 to <12	42 (39)	43 (38)	85 (38)
12 to <18	25 (23)	29 (25)	54 (24)
≥18	35 (32)	32 (28)	67 (30)
Race
White	95 (87)	91 (80)	186 (83)
Black or African American	1 (<1)	2 (2)	3 (1)
Asian	4 (4)	7 (6)	11 (5)
Other	9 (8)	14 (12)	23 (10)
Ethnicity
Hispanic or Latino	38 (35)	39 (34)	77 (35)
Not Hispanic or Latino	71 (65)	75 (66)	146 (65)

Source: Adapted from FDA Review

What are the benefits of this drug?

A higher proportion of subjects treated with FILSUVEZ than placebo gel had a first complete closure of the target wound within 45 days.

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

Table 2. Efficacy Results

Efficacy Parameter	FILSUVEZ N=109 %	Placebo Gel N=114 %	Treatment Difference 95% CI
Proportion of subjects with first complete closure of target wound within 45 days	41.3	28.9	0.8, 25.6
By EB subtypea
RDEB (n=175)	44.0	26.2	3.9, 31.6
DDEB (n=20)	50.0	50.0	-47.8, 47.8
JEB (n=26)	18.2	26.7	-40.4, 23.5
Proportion of subjects with first complete closure of target wound within 90 days	50.5	43.9	-6.2, 20.0

Source: FILSUVEZ Prescribing Information
^a Two subjects with EB simplex are not included
Abbreviations: CI, confidence interval; DDEB, dominant dystrophic epidermolysis bullosa; EB, epidermolysis bullosa; JEB, junctional epidermolysis bullosa; RDEB, recessive dystrophic epidermolysis bullosa

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

• Sex: The effect of FILSUVEZ was similar for females and males.
• Race: The number of patients of races other than White was small; therefore, differences in how FILSUVEZ worked among races could not be determined.
• Age: The observed effect of FILSUVEZ was larger for pediatric subjects than adult subjects. Because of limited data, this difference may be due to chance.

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

Table 3 summarizes the proportion of subjects with first complete closure of target wound within 45 days by subgroup.

Table 3. Efficacy Results by Sex, Race, Age, and Ethnicity

Parameter	FILSUVEZ N=109 n/Ns (%)	Placebo Gel N=114 n/Ns (%)	Treatment Difference 95% CI
Proportion of subjects with first complete closure of target wound within 45 days	45/109 (41.3)	33/114 (28.9)	0, 24.8
Age group, years
<4	5/7 (71.4)	4/10 (40.0)	-13.8, 76.6
4 to <12	18/42 (42.9)	10/43 (23.3)	0, 39.2
12 to <18	10/25 (40.0)	7/29 (24.1)	-8.9, 40.6
≥18	12/35 (34.3)	12/32 (37.5)	-26.2, 19.8
Sex
Male	27/68 (39.7)	18/66 (27.3)	-3.4, 28.3
Female	18/41 (43.9)	15/48 (31.3)	-7.4, 32.7
Race
White	39/95 (41.1)	29/91 (31.9)	-4.6, 23.0
Black or African American	0/1 (0)	1/2 (50.0)	-100, 19.3
Asian	1/4 (25.0)	1/7 (14.3)	-19.7, 91.2
Other	4/9 (44.4)	2/14 (14.3)	-7.1, 67.4
Ethnicity
Hispanic or Latino	17/38 (44.7)	15/39 (38.5)	-15.7, 28.3
Not Hispanic or Latino	28/71 (39.4)	18/75 (24.0)	0.5, 30.4

Source: Adapted from FDA Review
Abbreviations: CI, confidence interval; N, number of patients in treatment arm; n, number of patients meeting criteria; Ns, total number of patients for each specific subgroup and were assigned to that specific arm

What are the possible side effects?

The common adverse reaction reported in greater than 2% of those treated with FILSUVEZ was application site reaction (7.3%), which may include application site itching or pain.

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

Table 4. Adverse Reactions Occurring in ≥2% of Subjects

Adverse Reaction	FILSUVEZ N=109 n (%)	Placebo Gel N=114 n (%)
Application site reaction	8 (7.3)	7 (6.1)

Source: FILSUVEZ Prescribing Information

Local hypersensitivity and skin reactions have been reported in patients treated with FILSUVEZ, including urticaria and dermatitis.

Squamous cell carcinoma of the skin was reported as an adverse event in four recessive DEB subjects during the double-blind (n=1) and open-label (n=3) periods of the clinical trial. Two subjects had applied FILSUVEZ to the affected wounds. In general, squamous cell carcinoma is known to occur as a complication of recessive DEB.

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

• Sex: Because of limited data, differences in FILSUVEZ side effects between females and males could not be determined.
• Race: The number of patients of races other than White was small; therefore, differences in FILSUVEZ side effects among races could not be determined.
• Age: The occurrence of side effects was similar in patients younger and older than 18 years of age.

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

Table 5 summarizes the occurrence of any adverse event by subgroups.

Table 5. Side Effects by Sex and Age

Any Adverse Event	FILSUVEZ N=109 n/Ns (%)	Placebo Gel N=114 n/Ns (%)
Age group, years
<4	6/7 (85.7)	7/10 (70.0)
4 to <12	34/42 (81.0)	35/43 (81.4)
12 to <18	22/25 (88.0)	25/29 (86.2)
≥18	27/35 (77.1)	25/32 (78.1)
Sex
Male	53/68 (77.9)	56/66 (84.8)
Female	36/41 (87.8)	36/48 (75.0)

Source: Adapted from FDA Review
Abbreviations: N, number of patients in treatment arm; n, number of patients with adverse event; Ns, total number of patients for each specific subgroup and were assigned to that specific arm

The number of patients of races other than White was small; therefore, differences in FILSUVEZ side effects among races could not be determined.

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 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.

LINK TO DRUG PACKAGE INSERT

Back to Drug Trials Snapshots