Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
The safety of SIMTRIYO is based on studies in:
- Pediatric patients aged 4 to 17 years with ADHD who were exposed to one or more doses of SIMTRIYO in two 6-week randomized, double-blind, placebo-controlled studies (Studies 1 and 2) [see Clinical Studies (14)] and a long-term open-label study. SIMTRIYO is not approved for use in patients less than 6 years of age or weighing less than 20 kg [see Indications and Usage (1)]. In Studies 1 and 2, 608 pediatric patients 6 years of age and older were exposed to SIMTRIYO. A total of 394 pediatric patients 6 years of age and older were treated with SIMTRIYO for at least 6 months, and 286 were treated for 12 months or longer.
- Adult patients aged 18 to 55 years with ADHD who were exposed to another formulation of centanafadine [see Clinical Pharmacology (12.3)] in two 6-week randomized, double blind, placebo-controlled studies (Studies 3 and 4) [see Clinical Studies (14)] and a long-term open-label study. In Studies 3 and 4, 586 adult patients were exposed to another formulation of centanafadine. A total of 422 adult patients were exposed to another formulation of centanafadine for at least six months and 221 were exposed for 12 months or longer.
The most common adverse reactions (≥5% and greater than placebo) in the double-blind clinical trials were:
- Pediatric Patients Aged 6 to 12 Years: rash, decreased appetite (see Table 2).
- Pediatric Patients Aged 13 to 17 Years: decreased appetite, nausea, rash, headache, abdominal pain (see Table 3).
- Adults: headache, decreased appetite, insomnia, nausea, dry mouth, diarrhea (see Table 4).
The most common adverse reactions associated with discontinuation (≥1%) in the pediatric and adult double-blind clinical trials were rash, decreased appetite, nausea, and somnolence.
Adverse Reactions in Pediatric Patients 6 Years of Age and Older
The safety data below are from pediatric patients aged 6 to 17 years in Studies 1 and 2 who received SIMTRIYO 280 mg (or weight-based equivalent) once daily [see Clinical Studies (14)].
Table 2 presents adverse reactions reported in 2% or more of SIMTRIYO-treated pediatric patients aged 6 to 12 years and more frequently than placebo-treated patients in Study 1.
Table 2: Adverse Reactions in ≥2% of Pediatric Patients 6 to 12 Years of Age Treated with SIMTRIYO and Greater than Placebo in 6-Week Placebo-Controlled ADHD Study (Study 1) | Placebo (N=153) | SIMTRIYO High dose
(N=157) |
|---|
| Rash
| 0% | 9% |
| Decreased appetite | 3% | 8% |
| Fatigue
| 0% | 4% |
| Abdominal pain
| 2% | 4% |
| Nausea | 1% | 3% |
| Pharyngitis streptococcal | 2% | 3% |
| Diarrhea | 0% | 2% |
| Influenza | 0% | 2% |
Table 3 presents adverse reactions reported in 2% or more of SIMTRIYO-treated pediatric patients aged 13 to 17 years and more frequently than placebo-treated patients in Study 2.
Table 3: Adverse Reactions in ≥2% of Pediatric Patients 13 to 17 Years of Age Treated with SIMTRIYO and Greater than Placebo in 6-Week Placebo-Controlled ADHD Study (Study 2) | Placebo (N=147) | SIMTRIYO 280 mg/day (N=151) |
|---|
| Decreased appetite | 2% | 15% |
| Nausea | 3% | 10% |
| Rash
| 1% | 8% |
| Headache
| 6% | 7% |
| Abdominal pain
| 0% | 5% |
| Somnolence
| 3% | 4% |
| Fatigue
| 1% | 3% |
| Dizziness | 0% | 3% |
| Nasopharyngitis | 1% | 3% |
| Insomnia
| 1% | 3% |
| Irritability | 1% | 3% |
| Dry mouth | 0% | 2% |
| Weight decreased | 1% | 2% |
Adverse Reactions in Adults
The safety data below are based on pooled data from Studies 3 and 4 in adult patients with ADHD treated with another formulation of centanafadine for 6 weeks [see Clinical Studies (14)].
Table 4 lists adverse reactions reported in ≥2% of adult patients treated with another formulation of centanafadine and more frequently than placebo-treated patients.
Table 4: Adverse Reactions in ≥2% of Adults Treated with Another Centanafadine Formulation and Greater than Placebo in 6-Week Placebo-Controlled ADHD Studies (Studies 3 and 4) | | Another Centanafadine Formulation | Another Centanafadine Formulation |
|---|
| Placebo (N=290) | Low Dose
(N=294) | High Dose
(N=292) |
|---|
| Headache
| 7% | 5% | 8% |
| Decreased appetite | 2% | 5% | 7% |
| Insomnia
| 4% | 5% | 7% |
| Nausea | 2% | 2% | 7% |
| Dry mouth | 0% | 3% | 6% |
| Diarrhea | 1% | 2% | 5% |
| Irritability | 2% | 3% | 4% |
| Rash
| 2% | 2% | 4% |
| Abdominal pain
| 1% | 2% | 4% |
| Parasomnia
| 1% | 1% | 3% |
| Tachycardia
| 1% | 1% | 2% |
| Depressed mood
| 0% | 3% | 2% |
| Anxiety
| 1% | 2% | 2% |
| Upper respiratory tract infection | 2% | 5% | 2% |
Adverse Reactions Associated with Discontinuation
Pediatric Patients 6 to 12 Years of Age
In Study 1, 6% (10/157) of SIMTRIYO-treated patients aged 6 to 12 years discontinued due to adverse reactions versus 1% (2/153) of placebo-treated patients. The most frequently reported adverse reaction associated with discontinuation (1% or more and twice rate of placebo) was rash (2.5%).
Pediatric Patients 13 to 17 Years of Age
In Study 2, 8% (12/151) of SIMTRIYO-treated patients aged 13 to 17 years discontinued due to adverse reactions versus 0% (0/147) of placebo-treated patients. The most frequently reported adverse reactions (1% or more and twice rate of placebo) associated with discontinuation were rash (2%), decreased appetite (2%), nausea (2%), and somnolence (1%).
Adults
In Studies 3 and 4, 6% (18/292) of adult patients treated with the high dose of another formulation of centanafadine discontinued due to adverse reactions versus 5% (14/294) of patients treated with the low dose and 1% (4/290) of placebo-treated patients. The most frequently reported adverse reaction associated with discontinuation (1% or more and twice rate of placebo) was rash (2%).
Suicidal Ideation and Behavior
Pediatric Patients Aged 6 Years and Older
In the 6-week study in pediatric patients aged 6 to 12 years (Study 1), suicide attempt was reported in 0.7% (2/304) of SIMTRIYO-treated patients versus 0% in placebo (0/153). In the long-term open-label trial in pediatric patients aged 6 to 17 years, suicidal ideation was reported in 0.8% (5/620) of patients, leading to discontinuation in 0.6% (4/620).
Increases in Blood Pressure and Heart Rate
Pediatric Patients 6 to 12 Years of Age
Compared to placebo, short-term (6-week) treatment (Study 1) with SIMTRIYO in patients 6 to 12 years of age was associated with differences, ranging from +0.1 to +2.8 mmHg, in the mean absolute change from baseline systolic blood pressure (SBP) and with differences, ranging from -0.2 mmHg to +1.6 mmHg, in the mean absolute change from baseline diastolic blood pressure (DBP).
Patients enrolled in the long-term open-label study had mean absolute changes in baseline SBP ranging from +0.7 to +2.7 mmHg and in baseline DBP ranging from +0.5 to +2.8 mmHg through Week 88.
Pediatric Patients 13 to 17 Years of Age
During the 6-week trial (Study 2), the proportion of SIMTRIYO-treated patients 13 to 17 years of age who developed new-onset hypertension was 10.7% compared to 8.9% treated with placebo. Compared to placebo, short-term (6-week) treatment with SIMTRIYO in patients 13 to 17 years of age was associated with differences, ranging from +0.5 to +2.1 mmHg, in the mean absolute change from baseline SBP and with differences, ranging from +0.6 mmHg to +1.5 mmHg, in the mean absolute change from baseline DBP.
Patients enrolled in the long-term open-label study had mean absolute changes in baseline SBP ranging from +0.9 to +3.2 mmHg and in baseline DBP ranging from +1.7 to +3.1 mmHg through Week 88.
Adults
In Studies 3 and 4 in adults (18 to 55 years of age), increases in heart rate ≥20 beat per minute (bpm) in supine position at any visit occurred in 15% (44/292) of patients on the high dose of another formulation of centanafadine and 12% (34/294) on the low dose, versus 11% (32/290) on placebo. Increases in systolic blood pressure of ≥20 mmHg in supine position at any visit occurred in 9% (25/292) of patients treated with the high dose of another centanafadine formulation and 12% (36/294) of patients treated with the low dose, versus 7% (21/290) on placebo.
Psychiatric Adverse Reactions
Pediatric Patients 6 to 12 Years of Age
In Study 1, psychiatric adverse reactions occurring in <2% of SIMTRIYO-treated patients receiving the weight-based dose equivalent of 280 mg daily and greater than placebo included suicide attempt and insomnia. In a long-term open-label safety study, psychiatric adverse reactions led to discontinuation of SIMTRIYO in 2% of pediatric patients 6 to 12 years of age. Psychiatric adverse reactions leading to discontinuation included irritability, auditory hallucination, visual hallucination, major depression, altered mood, and suicidal ideation.
Pediatric Patients 13 to 17 Years of Age
In Study 2, psychiatric adverse reactions occurred in 9% of patients receiving 280 mg daily of SIMTRIYO compared with 3% of patients who received placebo. Irritability and insomnia were the most common psychiatric adverse reactions in this age group (see Table 3). Irritability occurred in 3% of patients receiving 280 mg SIMTRIYO compared with 1% of patients receiving placebo. Insomnia occurred in 3% of patients receiving 280 mg SIMTRIYO compared with 1% of patients receiving placebo. In a long-term open-label pediatric safety study, psychiatric adverse reactions led to discontinuation in 4% of pediatric patients 13 to 17 years of age. Psychiatric adverse reactions leading to discontinuation included suicidal ideation, depression, irritability, apathy, aggression, anxiety, defiant behavior, and feelings of worthlessness.
Adults
In Studies 3 and 4, psychiatric adverse reactions occurred in 16% of patients receiving the high dose of another centanafadine formulation, 14% of patients receiving the low dose, and 8% of patients receiving placebo. The most frequent psychiatric adverse reactions were insomnia, irritability, abnormal dreams, depressed mood, and anxiety (see Table 4). In a long-term open-label study in adults, 21% of patients experienced psychiatric adverse reactions. The most common psychiatric adverse reactions were insomnia (8%), anxiety (6%), and irritability (3%).
Hypersensitivity Reactions
In two other ADHD clinical trials, and one trial in an unapproved population, two adult patients reported angioedema, and one patient reported suspected anaphylactic reaction, some of these events required urgent treatment as outpatients.
Effects on Growth in Pediatric Patients 6 Years of Age and Older
Pediatric Patients 6 to 12 Years of Age
The mean baseline BMI in SIMTRIYO-treated patients 6 to 12 years of age compared to placebo was 20.4 kg/m2 and 20.0 kg/m2, respectively. Short-term (6-week) treatment (Study 1) with SIMTRIYO was associated with a mean change from baseline weight of -0.6 kg compared to +0.8 kg in placebo-treated patients at Week 6. The mean baseline weight z-score decreased by at least 0.5 in 0.8% of SIMTRIYO-treated patients compared to none in placebo-treated patients at Week 6. The mean baseline BMI z-score decreased by at least 0.5 in 7.3% of SIMTRIYO-treated patients compared to 3.2% of placebo-treated patients at Week 6.
In the SIMTRIYO long-term open-label study, 2.2% of patients had a change from baseline weight leading to a decrease in weight z-score by at least 1, 2.2% had a decrease in BMI z-score by at least 1, and 15.6% had a decrease in height z-score by at least 1 at Week 88.
Pediatric Patients 13 to 17 Years of Age
The mean baseline BMI in both SIMTRIYO- and placebo-treated patients 13 to 17 years of age was 24.4 kg/m2; however, placebo-treated patients had higher mean baseline weight (69 kg vs. 67.7 kg) and height (167.7 cm vs. 166.7 cm). Short-term (6-week) treatment (Study 2) with SIMTRIYO was associated with a mean change from baseline weight of -1.2 kg compared to +0.6 kg in placebo-treated patients at Week 6. The mean baseline weight z score decreased by at least 0.5 in 2% of SIMTRIYO-treated patients compared to none in placebo-treated patients at Week 6. The mean baseline BMI z-score decreased by at least 0.5 in 4.9% of SIMTRIYO-treated patients compared to none in placebo-treated patients at Week 6. In the SIMTRIYO long-term open-label study, 4.6% of patients had a change from baseline weight leading to a decrease in weight z-score by at least 1, 4.6% had a decrease in BMI z-score by at least 1, and 1.5% had a decrease in height z-score by at least 1 at Week 88.