Drug Trials Snapshots: BRINSUPRI
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 BRINSUPRI 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).
BRINSUPRI (brensocatib)
(Brin-SOO-pree)
Insmed, Inc.
Approval date: August 12, 2025
DRUG TRIALS SNAPSHOT SUMMARY:
What is the drug for?
BRINSUPRI is a dipeptidyl peptidase 1 (DPP1) inhibitor that is indicated for the treatment of non-cystic fibrosis bronchiectasis in adult and pediatric patients 12 years of age and older.
Non-cystic fibrosis bronchiectasis (NCFB) is a chronic and progressive inflammatory lung condition that can lead to breathing complications and death. People with NCFB have recurrent flare-ups called pulmonary exacerbations (PEx). During a PEx, patients experience worsening respiratory symptoms, such as cough, increased sputum, and fatigue, and need antibiotics for treatment. Each time a PEx occurs, the lungs are damaged, and this damage worsens the airways over time. As NCFB progresses, patients have more trouble with breathing and more frequent infections that require treatment with long-term antibiotics, oxygen, physiotherapy, and other drugs (e.g. mucolytics) to loosen mucus.
How is this drug used?
BRINSUPRI is an oral tablet that is taken by mouth once daily.
Who participated in the clinical trials?
The FDA approved BRINSUPRI based on evidence from two clinical trials, ASPEN and WILLOW, that enrolled 1,936 adult and 41 adolescent patients with NCFB. ASPEN enrolled patients in 402 centers, and WILLOW enrolled patients in 101 centers.
The trials were conducted in 38 countries (Argentina, Australia, Austria, Belgium, Brazil, Bulgaria, Canada, Chile, Colombia, Denmark, Estonia, France, Germany, Greece, Hungary, Ireland, Israel, Italy, Japan, Latvia, Lithuania, Malaysia, Mexico, the Netherlands, New Zealand, Peru, Poland, Portugal, South Korea, Serbia, Singapore, Slovakia, Spain, Taiwan, Thailand, Turkey, the United Kingdom, and the United States) and included a total of 309 patients from the United States. Among the 1,977 enrolled patients, all of them were evaluated for efficacy (Intent-to-Treat population) and 1,974 patients were evaluated for safety.
How were the trials designed?
BRINSUPRI was evaluated in two clinical trials that evaluated the efficacy and safety of BRINSUPRI at 10 mg and 25 mg doses administered by mouth once daily over 52 weeks (ASPEN) and 24 weeks (WILLOW). ASPEN enrolled 1,680 adults and 41 adolescents with NCFB, and WILLOW enrolled 256 adults with NCFB. In both trials, subjects were randomized to receive BRINSUPRI 10 mg, BRINSUPRI 25 mg, or placebo. The primary efficacy endpoints of both trials assessed PEx, which were defined as a worsening of three or more major symptoms (e.g., cough, sputum volume or color or consistency, breathlessness, fatigue, and coughing up blood) over 48 hours that required treatment with antibiotics.
How were the trials designed?
The efficacy and safety of BRINSUPRI 10 mg and 25 mg doses were evaluated in two randomized, double-blind, placebo-controlled, parallel group trials named ASPEN and WILLOW. ASPEN was a phase 3 trial enrolling patients with NCFB aged 12 years and older. WILLOW was a phase 2 trial enrolling patients with NCFB aged 18 years and older.
In both trials, adult patients were randomized in a 1:1:1 ratio to receive BRINSUPRI 10 mg, BRINSUPRI 25 mg, or placebo for a 52-week (ASPEN) or 24-week (WILLOW) treatment period. Adolescent patients in the ASPEN trial were randomized in a 2:2:1 ratio for a 52-week treatment period.
The primary efficacy endpoint in the ASPEN trial was the rate of PEx over a one-year period (annualized rate). In WILLOW, the primary endpoint measured how long it takes for subjects to have a PEx (time to first PEx). Other efficacy endpoints assessed in ASPEN included the number of subjects who did not have any PEx during the treatment period (exacerbation free), the annualized rate of severe PEx (PEx that required intravenous antibiotics or hospitalization), and the change from baseline in post-bronchodilator forced expiratory volume in 1 second (FEV1), a marker of lung function.
DEMOGRAPHICS SNAPSHOT
Figure 1 summarizes how many male and female patients were enrolled in the combined trials used to evaluate the efficacy of BRINSUPRI.
Figure 1. Baseline Demographics by Sex, Intent-to-Treat Population
Source: Adapted from FDA Review
Figure 2 summarizes how many patients by race were enrolled in the combined trials used to evaluate the efficacy of BRINSUPRI.
Figure 2. Baseline Demographics by Race, Intent-to-Treat Population
Source: Adapted from FDA Review
Figure 3 summarizes how many patients by age were enrolled in the combined trials used to evaluate the efficacy of BRINSUPRI.
Figure 3. Baseline Demographics by Age, Intent-to-Treat Population
Source: Adapted from FDA Review
Figure 4 summarizes how many patients by ethnicity were enrolled in the combined trials used to evaluate the efficacy of BRINSUPRI.
Figure 4. Baseline Demographics by Ethnicity, Intent-to-Treat Population
Source: Adapted from FDA Review
Who participated in the trials?
Table 1. Baseline Demographics of Efficacy Trials, ASPEN and WILLOW
| Characteristic | BRINSUPRI 10 mg N=665 n (%) | BRINSUPRI 25 mg N=662 n (%) | Placebo N=650 n (%) |
|---|---|---|---|
| Sex | |||
| Female | 442 (66.5) | 422 (63.7) | 417 (64.2) |
| Male | 223 (33.5) | 240 (36.3) | 233 (35.8) |
| Age group, years | |||
| 12 to <18 | 17 (2.6) | 16 (2.4) | 8 (1.2) |
| 18 to <65 | 323 (48.6) | 296 (44.7) | 328 (50.5) |
| ≥65 | 325 (48.9) | 350 (52.9) | 314 (48.3) |
| Race | |||
| White | 507 (76.2) | 508 (76.7) | 476 (73.2) |
| Asian | 68 (10.2) | 69 (10.4) | 77 (11.8) |
| American Indian or Alaska Native | 8 (1.2) | 6 (<1) | 9 (1.4) |
| Black or African American | 2 (<1) | 5 (<1) | 3 (<1) |
| Native Hawaiian or Pacific Islander | 2 (<1) | 1 (<1) | 2 (<1) |
| Multiple | 15 (2.3) | 11 (1.7) | 11 (1.7) |
| Other | 15 (2.3) | 14 (2.1) | 11 (1.7) |
| Not reported or Unknown | 48 (7.2) | 46 (6.9) | 59 (9.1) |
| Ethnicity | |||
| Hispanic or Latino | 179 (26.9) | 168 (25.4) | 170 (26.2) |
| Not Hispanic or Latino | 471 (70.8) | 480 (72.5) | 460 (70.8) |
| Not reported or Unknown | 15 (2.3) | 14 (2.1) | 20 (3.1) |
Source: Adapted from FDA Review
Abbreviations: N, number of patients in treatment arm; n, number of patients in subgroup
What are the benefits of this drug?
In ASPEN, patients with NCFB aged 12 years and older taking BRINSUPRI 10 mg and 25 mg had a reduction of 21% and 19%, respectively, in the annualized rate of PEx compared to placebo. In WILLOW, patients with NCFB aged 18 years and older taking BRINSUPRI 10 mg and 25 mg had a longer time until their first PEx compared to placebo.
What are the benefits of this drug (results of trials used to assess efficacy)?
Table 2 and Figure 5 summarize the efficacy results of BRINSUPRI treatment in the ASPEN trial. The primary measure for efficacy was the annualized rate of PEx. Other measures of efficacy in ASPEN included time to first PEx, the proportion of patients that were PEx free, the annualized rate of severe PEx, and the change from baseline in the lung function marker FEV1. Patients in the ASPEN trial who were taking BRINSUPRI 10 mg and 25 mg had a reduction in the annualized rate of PEx (Table 2), which means they had fewer PEx over a one-year period compared to patients taking placebo (Figure 5). Patients taking BRINSUPRI also had a reduction in the annualized rate of severe PEx, had a longer time to first PEx, and were more likely to be free of PEx at Week 52 compared to patients taking placebo (Table 2). Like the patients in ASPEN, patients in WILLOW who were taking BRINSUPRI had a longer time to first PEx compared to patients taking placebo. In both trials, patients taking BRINSUPRI 10 mg or 25 mg had similar responses to both doses.
Table 2. Efficacy Results through Week 52 in the Intent-to-Treat Population, ASPEN
| Parameter | BRINSUPRI 10 mg N=583 | BRINSUPRI 25 mg N=575 | Placebo N=563 |
|---|---|---|---|
| Annualized rate of PEx | 1.02 | 1.04 | 1.29 |
| Rate ratio compared to placebo (95% CI) | 0.79 (0.68, 0.92) | 0.81 (0.69, 0.94) | NA |
| Median time to first PEx in weeks | 49.0 | 50.7 | 36.7 |
| Hazard ratio compared to placebo (95% CI) | 0.81 (0.70, 0.95) | 0.83 (0.70, 0.97) | NA |
| Proportion of patients that were PEx free at Week 52, % | 48.5 | 48.5 | 40.3 |
| Odds ratio compared to placebo (95% CI) | 1.41 (1.11, 1.81) | 1.40 (1.10, 1.79) | NA |
| Annualized rate of severe PEx | 0.14 | 0.14 | 0.19 |
| Rate ratio compared to placebo (95% CI) | 0.74 (0.51, 1.09) | 0.74 (0.52, 1.06) | NA |
| LS mean change from baseline in post-bronchodilator FEV1 (mL) at Week 52 | -50 | -24 | -62 |
| Difference compared to placebo (95% CI) | 11 (−14, 37) | 38 (11, 65) | NA |
Source: Adapted from FDA Review
Abbreviations: CI, confidence interval; FEV1, forced expiratory volume in 1 second; LS, least squares; NA, not applicable; PEx, pulmonary exacerbation
Figure 5. Cumulative Mean Number of Pulmonary Exacerbations in the Intent-to-Treat Population, ASPEN
Source: Adapted from FDA Review
Abbreviations: No., number; QD, once daily
Were there any differences in how well the drug worked in clinical trials among sex, race, and age?
- Sex: BRINSUPRI worked similarly in males and females.
- Race: The number of patients of races other than White was small; therefore, differences in how well BRINSUPRI worked among races could not be determined.
- Age: BRINSUPRI worked similarly in patients 12 to less than 18 years of age, 18 to less than 65 years of age, or at least 65 years of age.
- Ethnicity: BRINSUPRI worked similarly among different ethnicities (Hispanic or Latino and not Hispanic or Latino).
Were there any differences in how well the drug worked in clinical trials among sex, race, and age groups?
Table 3 summarizes the primary efficacy endpoint results in ASPEN by age, sex, race, and ethnicity. Because most of the race subgroups were too small, the rate ratio of PEx could not be estimated. Race estimates are provided only for White and Asian subgroups from the ASPEN trial. In WILLOW, the majority of enrolled subjects were White and not Hispanic, and the remaining race and ethnicity subgroups were too small to estimate the rate ratio of PEx. Overall, there were no significant differences in the efficacy of BRINSUPRI 10 mg and 25 mg doses based on demographic subgroups.
Table 3. Efficacy Results by Subgroup, Rate Ratio of Pulmonary Exacerbations Through Week 52 Between BRINSUPRI and Placebo, Intent-To-Treat Population, ASPEN
| Subgroup | n[B10], n[B25], n[P] | BRINSUPRI 10 mg vs. Placebo Rate Ratio (95% CI) | BRINSUPRI 25 mg vs. Placebo Rate Ratio (95% CI) |
|---|---|---|---|
| Age group, years | |||
| 12 to <18 | 17, 16, 8 | 0.41 (0.11, 1.58) | 0.73 (0.20, 2.68) |
| 18 to <65 | 289, 257, 295 | 0.81 (0.66, 0.99) | 0.70 (0.57, 0.86) |
| ≥65 | 277, 302, 260 | 0.79 (0.63, 0.99) | 0.93 (0.74, 1.15) |
| Sex | |||
| Female | 385, 360, 362 | 0.81 (0.68, 0.96) | 0.83 (0.70, 1.00) |
| Male | 198, 215, 201 | 0.75 (0.57, 1.00) | 0.75 (0.57, 0.98) |
| Race | |||
| Asian | 63, 64, 64 | 0.40 (0.23, 0.67) | 0.41 (0.24, 0.70) |
| White | 431, 430, 405 | 0.79 (0.67, 0.94) | 0.79 (0.67, 0.93) |
| Ethnicity | |||
| Hispanic or Latino | 177, 164, 170 | 0.94 (0.70, 1.26) | 0.92 (0.69, 1.24) |
| Not Hispanic or Latino | 391, 397, 373 | 0.73 (0.61, 0.87) | 0.77 (0.64, 0.91) |
Source: Adapted from FDA Review
Abbreviations: CI, confidence interval; n[B10], number of subjects in the BRINSUPRI 10 mg subset; n[B25], number of subjects in the BRINSUPRI 25 mg subset; n[P], number of subjects in the placebo subset
What are the possible side effects?
The most common side effects of BRINSUPRI included upper respiratory tract infections, headache, rash, dry skin, hyperkeratosis (skin thickening), and hypertension (high blood pressure). Less common side effects of BRINSUPRI include abnormal liver blood test results, alopecia (hair loss), and skin cancers. Some of these side effects occurred more often for patients taking the 25 mg dose than for those taking the 10 mg dose.
BRINSUPRI may cause serious side effects including skin problems and dental problems. Tell your healthcare provider about any new skin symptoms. Your healthcare provider may send you to a dermatologist for a skin exam if needed. Because of the risk of dental problems, it is important to get regular dental checkups and to brush and clean your teeth as recommended by your dentist while taking BRINSUPRI. Tell your healthcare provider and contact your dentist if you have new gum or teeth symptoms.
What are the possible side effects (results of trials used to assess safety)?
The safety of BRINSUPRI was evaluated in 1,719 adults and 41 adolescents with NCFB who were enrolled in the ASPEN and WILLOW trials. Table 4 summarizes the side effects seen in the ASPEN trial that occurred more frequently in the patients taking BRINSUPRI and at a rate of 2% or more. These common side effects included upper respiratory tract infections, headache, rash, dry skin, hyperkeratosis, and hypertension. Other less common side effects included increased liver function tests, skin cancers, and alopecia. More serious potential side effects include dermatologic (skin) reactions and gingival and periodontal (gum and teeth) reactions. Patients taking the 25 mg dose experienced some of these side effects more often than those taking the 10 mg dose.
Table 4. Safety Results, Adverse Reactions With BRINSUPRI With an Incidence of >2% and More Common Than Placebo in ASPEN
| Adverse Reaction | BRINSUPRI 10 mg QD N=582 n (%) | BRINSUPRI 25 mg QD N=574 n (%) | Placebo N=563 n (%) |
|---|---|---|---|
| Upper respiratory tract infection1 | 157 (27) | 169 (29) | 141 (25) |
| Headache | 39 (7) | 49 (9) | 39 (7) |
| Rash2 | 25 (4) | 35 (6) | 22 (4) |
| Dry skin3 | 17 (3) | 25 (4) | 8 (1) |
| Hyperkeratosis4 | 8 (1) | 16 (3) | 5 (1) |
| Hypertension | 28 (5) | 13 (2) | 17 (3) |
Source: Adapted from the FDA Review
1 Upper respiratory tract infection includes coronavirus infection, COVID-19, influenza, upper respiratory tract infection, viral infection, and viral upper respiratory tract infection.
2 Rash includes rash, rash maculo-papular, rash pruritic, rash erythematous, dermatitis, and erythema.
3 Dry skin includes dry skin, chapped lips, cheilitis, lip dry, skin exfoliation, skin fissures, xeroderma, and xerosis.
4 Hyperkeratosis includes hyperkeratosis, palmoplantar keratoderma, and skin hypertrophy.
Abbreviations: N, number of patients in treatment arm; n, number of patients with adverse event; QD, once daily
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 number of patients of races other than White was small; therefore, differences in the occurrence of side effects by race could not be determined.
- Age: The occurrence of side effects was similar in patients 12 to less than 18 years of age, 18 to less than 65 years of age, or at least 65 years of age.
- Ethnicity: The occurrence of side effects was similar by ethnicity (Hispanic or Latino and not Hispanic or Latino).
Were there any differences in side effects of the clinical trials among sex, race, and age groups?
A safety analysis by key demographic subgroup including age, sex at birth, race, ethnicity, and region (United States versus rest of the world) was performed. There were no significant differences noted between subgroups. The number of patients reporting at least one side effect by demographic subgroups are reviewed in Table 5 for the ASPEN trial.
Table 5. Side Effects by Sex, Race, Age, and Ethnicity, Safety Population, ASPEN
| Characteristic | BRINSUPRI 10 mg N=582 n/Ns (%) | BRINSUPRI 25 mg N=574 n/Ns (%) | Placebo N=563 n/Ns (%) |
|---|---|---|---|
| Sex | |||
| Female | 307/384 (79.9) | 285/359 (79.4) | 294/362 (81.2) |
| Male | 145/198 (73.2) | 155/215 (72.1) | 154/201 (76.6) |
| Age group, years | |||
| 12 to <18 | 14/17 (82.4) | 10/16 (62.5) | 7/8 (87.5) |
| 18 to <65 | 229/288 (79.5) | 192/256 (75.0) | 232/295 (78.6) |
| ≥65 | 209/277 (75.5) | 238/302 (78.8) | 209/260 (80.4) |
| Age group ≥75, years | |||
| ≥75 | 65/83 (78.3) | 68/84 (81.0) | 78/93 (83.9) |
| Race | |||
| American Indian or Alaska Native | 5/8 (62.5) | 5/6 (83.3) | 7/9 (77.8) |
| Asian | 55/63 (87.3) | 48/64 (75.0) | 54/64 (84.4) |
| Black or African American | 2/2 (100) | 5/5 (100) | 2/3 (66.7) |
| White | 332/431 (77.0) | 330/430 (76.7) | 325/405 (80.2) |
| Native Hawaiian or other Pacific Islander | 1/1 (100) | 0/0 (NA) | 0/1 (0) |
| Multiple | 6/15 (40.0) | 3/11 (27.3) | 4/11 (36.4) |
| Not reported | 25/30 (83.3) | 28/32 (87.5) | 39/45 (86.7) |
| Other | 13/15 (86.7) | 12/13 (92.3) | 5/11 (45.5) |
| Unknown | 13/17 (76.5) | 9/13 (69.2) | 12/14 (85.7) |
| Ethnicity | |||
| Hispanic or Latino | 111/177 (62.7) | 106/163 (65.0) | 122/170 (71.8) |
| Not Hispanic or Latino | 329/390 (84.4) | 323/397 (81.4) | 307/373 (82.3) |
| Not reported | 11/13 (84.6) | 10/13 (76.9) | 16/17 (94.1) |
| Unknown | 1/2 (50.0) | 1/1 (100) | 3/3 (100) |
| Is in United States | |||
| United States | 66/80 (82.5) | 63/81 (77.8) | 63/79 (79.7) |
| Rest of the world | 386/502 (76.9) | 377/493 (76.5) | 385/484 (79.5) |
Source: Adapted from FDA Review
Abbreviations: N, number of patients in treatment arm; n, number of patients with adverse event; NA, not applicable; Ns, total number of patients for each specific subgroup and were assigned to that specific arm
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.