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  5. Drug Trials Snapshots: LETYBO
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Drug Trials Snapshots: LETYBO

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 LETYBO Prescribing Information for all 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).

LETYBO (letibotulinumtoxinA)
(le tye' boe)
Hugel, Inc.
Approval date: February 29, 2024


DRUG TRIALS SNAPSHOT SUMMARY:

What is the drug for?

LETYBO is a drug used in adults to temporarily improve the appearance of moderate to severe glabellar lines (wrinkles between the eyebrows).

How is this drug used?

LETYBO is given by a healthcare provider directly into the muscle through a needle (known as an intramuscular injection). It is injected into five different sites of the muscles of the frown lines. LETYBO should not be given more frequently than every three months.

Who participated in the clinical trials?

The FDA approved LETYBO based on evidence from three clinical trials (BLESS I [NCT02677298], BLESS II [NCT02677805], and BLESS III [NCT03985982]) of 1,271 patients with moderate to severe wrinkles between the eyebrows for efficacy and safety assessment. These trials were conducted at 31 sites in the United States and European Union.

How were the trials designed?

The benefit and side effects of LETYBO were primarily evaluated in three clinical trials.

All three trials enrolled patients 18 to 75 years old with moderate to severe glabellar lines (wrinkles between the eyebrows). Patients received a single intramuscular injection of LETYBO or placebo at five sites within the muscles between the eyebrows.

The benefit of LETYBO was assessed by determining the proportion of patients achieving a score of 0 or 1 (none or mild) and at least a 2-grade improvement of wrinkles between the eyebrows at maximum frown from baseline to Week 4. Improvement of wrinkles between the eyebrows at maximum frown was assessed independently by both the investigator and the patient using the Glabellar Line Scale (GLS). The GLS is a 4-point grading scale (0 = none, 1 = mild, 2 = moderate, 3 = severe).


DEMOGRAPHICS SNAPSHOT

Figure 1 summarizes how many male and female participants were enrolled in the combined clinical trials used to evaluate the efficacy of LETYBO.

Figure 1. Baseline Demographics by Sex

Pie chart summarizing how many male and female patients were in the clinical trial. In total, 110 (9%) male patients and 1,161 (91%) female patients participated in the clinical trial.

Source: Adapted from FDA Review

Figure 2 summarizes the percentage of participants by race enrolled in the combined clinical trials used to evaluate the efficacy of LETYBO.

Figure 2. Baseline Demographics by Race

Pie chart summarizing how many White, Black or African American, Asian, American Indian or Alaska Native, Native Hawaiian or Pacific Islander, and other patients were in the clinical trial. In total, 1,153 (90.7%) White patients, 87 (6.8%) Black or African American patients, 18 (1.4%) Asian patients, 3 (0.2%) American Indian or Alaska Native patients, 1 (0.1%) Native Hawaiian or Pacific Islander patients, and 9 (0.7%) other patients participated in the clinical trial.

Source: Adapted from FDA Review

Figure 3 summarizes the percentage of participants by age enrolled in the combined clinical trials used to evaluate the efficacy of LETYBO.

Figure 3. Baseline Demographics by Age

Pie chart summarizing how many patients by age were in the clinical trial. In total, 1,119 (88%) patients between 18 and 64 years of age and 152 (12%) patients between 65 and 75 years of age participated in the clinical trial.

Source: Adapted from FDA Review

Figure 4 summarizes the percentage of participants by ethnicity enrolled in the combined clinical trials used to evaluate the efficacy of LETYBO.

Figure 4. Baseline Demographics by Ethnicity

Pie chart summarizing how many Hispanic, not Hispanic, and missing patients were in the clinical trial. In total, 161 (13%) Hispanic or Latino patients, 1,101 (86%) not Hispanic or Latino patients, and 9 (1%) missing patients participated in the clinical trial.

Source: Adapted from FDA Review

What are the benefits of this drug?

In all three trials, patients with moderate to severe wrinkles between the eyebrows had improvement of frown lines four weeks after treatment with LETYBO. In Trial BLESS I, 47% of patients treated with LETYBO had temporary improvement of wrinkles between the eyebrows compared to 0% of patients in the group that received placebo. In Trial BLESS II, 49% of patients treated with LETYBO had temporary improvement of wrinkles between the eyebrows compared to 2% of patients in the group that received placebo. In Trial BLESS III, 65% of patients treated with LETYBO had temporary improvement of wrinkles between the eyebrows compared to 0% of patients in the group that received placebo.

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

  • Sex: The majority of patients were female. The number of male patients was limited; therefore, differences in how well LETYBO worked in male patients compared to female patients could not be determined.
  • Race: The majority of patients were White. The number of patients in other races were limited; therefore, differences in how well LETYBO worked among races could not be determined.
  • Age: The majority of patients were younger than 65 years of age; therefore, differences in how well LETYBO worked among younger versus older age groups could not be determined.

What are the possible side effects?

Botulinum toxin products may spread from the area of injection to other areas and cause serious life-threatening side effects including swallowing and difficulty breathing that could lead to death. Spread of botulinum toxin products to other areas can also cause loss of strength and muscle weakness, double vision, blurred vision and drooping eyelids, hoarseness or change or loss of voice, trouble saying words clearly, and loss of bladder control.

Other serious side effects of botulinum toxin products include severe allergic reactions and heart attack.

The most common side effects of LETYBO are headache, drooping of eyelid and brow, and twitching of eyelid.

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

  • Sex: The majority of patients were female. The number of male patients was limited; therefore, differences in the occurrence of side effects among male patients compared to female patients could not be determined.
  • Race: The majority of patients were White. The number of patients in other races were limited; therefore, differences in in the occurrence of side effects among races could not be determined.
  • Age: The majority of patients were younger than 65 years of age; therefore, differences in the occurrence of side effects among younger and older age groups 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 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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