A Phase 2 interventional study of PDC-1421 Capsule and Placebo in Attention-Deficit Hyperactivity Disorder (ADHD), sponsored by BioLite, Inc.. Completed at 6 sites in 2 countries. Open to participants aged 18 Years to 70 Years. Per ClinicalTrials.gov, last updated 2026-05-06.
Sponsored by BioLite, Inc. · Phase 2, Interventional, and Treatment
Part II is a double-blind, randomized, parallel-group, placebo-controlled study. The primary objective of this trial is to determine the effective doses and treatment period of PDC-1421 Capsule in subjects with ADHD. The secondary objective is to evaluate the safety of PDC-1421 Capsule in subjects receiving PDC-1421 at various dose levels.
The screening phase is intended for diagnosing and assessing the patient for possible inclusion in the study and for providing an adequate washout period.
At the first stage, a number of 69 subjects will be randomly assigned on a 1:1:1 basis to one of the three arms (1 PDC-1421 Capsule plus 1 placebo TID, 2 PDC-1421 Capsules TID, 2 placebo TID) for 8 weeks and evaluated the safety and efficacy every two weeks during the treatment period. An interim analysis will be conducted to evaluate the efficacy of PDC-1421 and to decide whether it is necessary to enter the second stage of the Part II study in which 30 subjects will be randomly assigned on a 1:1:1 basis to one of the three treatment arms and receive the same treatment.
Simple descriptive statistics with a 95% confidence interval will be performed with data collected in this study wherever applicable. The safety and efficacy data will be analyzed using the non-parametric method wherever appropriate.
The primary endpoint will be analyzed by chi-square test, while the secondary endpoints will be analyzed using the ANOVA or Kruskal-Wallis non-parametric ANOVA test for continuous endpoints and chi-square test for binary endpoints.
1,514 studies on the registry are indexed under Attention Deficit Disorder with Hyperactivity; 255 are open to participants now.
This study's enrollment of 99 is above the median of 72 across 1,207 interventional studies indexed under Attention Deficit Disorder with Hyperactivity.
Browse Attention Deficit Disorder with Hyperactivity studies →BioLite, Inc. is the lead sponsor of 7 studies on the registry; 3 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Two placebo capsules thrice daily for 56 days (8 weeks).
Drug: Placebo
One placebo capsule and 1 PDC-1421 Capsule, thrice daily for 56 days (8 weeks).
Drug: PDC-1421 Capsule · Drug: Placebo
Two PDC-1421 Capsules thrice daily for 56 days (8 weeks).
Drug: PDC-1421 Capsule
PDC-1421 Capsule is a botanical investigational new drug containing the extract of Radix Polygalae (Polygala tenuifolia Willd.) as the active ingredient.
Also known as: Extract of Radix Polygalae
The placebo contained corn starch.
Also known as: Corn Starch
Number of Participants With Improvement ≥ 40% in ADHD-RS-IV From Baseline up to 8 Weeks Treatment
The ADHD-RS-IV with Adult Prompts is an 18-item scale based on the DSM-IV-TR criteria for ADHD that provides a rating of the severity of symptoms. The adult prompts serve as a guide to explore more fully the extent and severity of ADHD symptoms and create a framework to ascertain impairment. The odd-numbered 9 items assess inattentive symptoms and the even-numbered 9 items assess hyperactive-impulsive symptoms. Scoring is based on a 4-point, yielding a possible total score of 0-54. Likert-type severity scale: 0 = Never or Rarely, 1 = Sometimes, 2 = Often, 3 = Very Often. Clinicians should score the highest score that is generated for the prompts for each item. The ADHD-RS-IV was assessed from Visit 1 to Visit 7 by the investigator.
Time frame: 8 weeks
Number of Participants With a CGI Score of 2 or Lower From Baseline up to 8 Weeks Treatment
Clinical Global Impression-Severity (CGI-S) and Clinical Global Impression-Improvement (CGI-I) score of 2 or lower. The CGI-S is rated on a 7-point scale, with the severity of illness scale using a range of responses from 1 (normal) through to 7 (amongst the most severely ill patients). CGI-I scores range from 1 (very much improved) through to 7 (very much worse).
Time frame: 8 weeks
Change From Baseline up to 8 Weeks in the Sluggish Cognitive Tempo (K-SCT) Score.
The K-SCT rating scale queries 15 Sluggish Cognitive Tempo symptoms rated from 0 = Never or Rarely, 1 = Sometimes, 2 = Often, 3 = Very Often, grouped into latent factors of daydreaming, working memory problems, and subjective sleepiness/tiredness. The range for the Total Score is 0-45. The higher values represent a worse outcome for the total score and subscore.
Time frame: 8 weeks
Change From Baseline up to 8 Weeks in the ADHD-RS-IV Total Scale.
The ADHD-RS-IV with Adult Prompts is an 18-item scale base on the DSM-IV-TR criteria for ADHD that provides a rating of the severity of symptoms. The adult prompts serve as a guide to explore more fully the extent and severity of ADHD symptoms and create a framework to ascertain impairment. The odd-numbered 9 items assess inattentive symptoms and the even-numbered 9 items assess hyperactive-impulsive symptoms. Scoring is based on a 4-point, yielding a possible summed "total score" of 0-54. The higher values represent a worse outcome for the total score and subscore. Likert-type severity scale: 0 = Never or Rarely, 1 = Sometimes, 2 = Often, 3 = Very Often.
Time frame: 8 weeks
Number of Participants With Symptom Remission in ADHD-RS-IV From Baseline up to 8 Weeks Treatment
The ADHD-RS-IV with Adult Prompts is an 18-item scale base on the DSM-IV-TR criteria for ADHD that provides a rating of the severity of symptoms. The adult prompts serve as a guide to explore more fully the extent and severity of ADHD symptoms and create a framework to ascertain impairment. The odd-numbered 9 items assess inattentive symptoms and the even-numbered 9 items assess hyperactive-impulsive symptoms. Scoring is based on a 4-point, yielding a possible summed "total score" of 0-54, "inattentive subscore" of 0-27, and "hyperactive-impulsive subscore" of 0-27. The higher values represent a worse outcome for the total score and subscore. Likert-type severity scale: 0 = Never or Rarely, 1 = Sometimes, 2 = Often, 3 = Very Often.
Time frame: 8 weeks
Change From Baseline up to 8 Weeks Treat in the Conners' Adult Attention-Deficit/Hyperactivity Disorder Rating Scale-Self Report: Short Version (CAARS-S:S) ADHD Index of T-score.
Conners' Adult Attention-Deficit/Hyperactivity Disorder Rating Scale-Self Report: Short Version (CAARS-S:S) consists of 26 items rated from 0=not at all, never to 3=very much, very frequently. Four subscales each composed of 5 items (A: inattention/memory problems; B: hyperactivity/restlessness; C: impulsivity/emotional lability; and D: problems with self-concept) as well as a 12-item ADHD index can be computed. The raw scores were converted into standard T-scores. The higher T-scores represent a better or worse outcome. A T-score is a standard score with a mean of 50 and a standard deviation of 10 in all samples and across all scales
Time frame: 8 weeks
| Milestone | Placebo | Low-dose | High-dose |
|---|---|---|---|
| Started | 22 | 23 | 24 |
| Completed | 19 | 22 | 19 |
| Not completed | 3 | 1 | 5 |
The ADHD-RS-IV with Adult Prompts is an 18-item scale based on the DSM-IV-TR criteria for ADHD that provides a rating of the severity of symptoms. The adult prompts serve as a guide to explore more fully the extent and severity of ADHD symptoms and create a framework to ascertain impairment. The odd-numbered 9 items assess inattentive symptoms and the even-numbered 9 items assess hyperactive-impulsive symptoms. Scoring is based on a 4-point, yielding a possible total score of 0-54. Likert-type severity scale: 0 = Never or Rarely, 1 = Sometimes, 2 = Often, 3 = Very Often. Clinicians should score the highest score that is generated for the prompts for each item. The ADHD-RS-IV was assessed from Visit 1 to Visit 7 by the investigator.
| Participants | Placebo | Low-dose | High-dose |
|---|---|---|---|
| Number of Participants With Improvement ≥ 40% in ADHD-RS-IV From Baseline up to 8 Weeks Treatment | 11 | 9 | 10 |
Clinical Global Impression-Severity (CGI-S) and Clinical Global Impression-Improvement (CGI-I) score of 2 or lower. The CGI-S is rated on a 7-point scale, with the severity of illness scale using a range of responses from 1 (normal) through to 7 (amongst the most severely ill patients). CGI-I scores range from 1 (very much improved) through to 7 (very much worse).
| Participants | Placebo | Low-dose | High-dose |
|---|---|---|---|
| Number of Participants With a CGI Score of 2 or Lower From Baseline up to 8 Weeks Treatment | 6 | 9 | 9 |
The K-SCT rating scale queries 15 Sluggish Cognitive Tempo symptoms rated from 0 = Never or Rarely, 1 = Sometimes, 2 = Often, 3 = Very Often, grouped into latent factors of daydreaming, working memory problems, and subjective sleepiness/tiredness. The range for the Total Score is 0-45. The higher values represent a worse outcome for the total score and subscore.
| score on a scale | Placebo | Low-dose | High-dose |
|---|---|---|---|
| Change From Baseline up to 8 Weeks in the Sluggish Cognitive Tempo (K-SCT) Score. | -5.05 ± 8.27 | -6.04 ± 8.29 | -6.54 ± 8.04 |
The ADHD-RS-IV with Adult Prompts is an 18-item scale base on the DSM-IV-TR criteria for ADHD that provides a rating of the severity of symptoms. The adult prompts serve as a guide to explore more fully the extent and severity of ADHD symptoms and create a framework to ascertain impairment. The odd-numbered 9 items assess inattentive symptoms and the even-numbered 9 items assess hyperactive-impulsive symptoms. Scoring is based on a 4-point, yielding a possible summed "total score" of 0-54. The higher values represent a worse outcome for the total score and subscore. Likert-type severity scale: 0 = Never or Rarely, 1 = Sometimes, 2 = Often, 3 = Very Often.
| score on a scale | Placebo | Low-dose | High-dose |
|---|---|---|---|
| Change From Baseline up to 8 Weeks in the ADHD-RS-IV Total Scale. | -12.14 ± 10.56 | -13.61 ± 10.02 | -11.75 ± 10.20 |
The ADHD-RS-IV with Adult Prompts is an 18-item scale base on the DSM-IV-TR criteria for ADHD that provides a rating of the severity of symptoms. The adult prompts serve as a guide to explore more fully the extent and severity of ADHD symptoms and create a framework to ascertain impairment. The odd-numbered 9 items assess inattentive symptoms and the even-numbered 9 items assess hyperactive-impulsive symptoms. Scoring is based on a 4-point, yielding a possible summed "total score" of 0-54, "inattentive subscore" of 0-27, and "hyperactive-impulsive subscore" of 0-27. The higher values represent a worse outcome for the total score and subscore. Likert-type severity scale: 0 = Never or Rarely, 1 = Sometimes, 2 = Often, 3 = Very Often.
| Participants | Placebo | Low-dose | High-dose |
|---|---|---|---|
| Number of Participants With Symptom Remission in ADHD-RS-IV From Baseline up to 8 Weeks Treatment | 9 | 4 | 7 |
Conners' Adult Attention-Deficit/Hyperactivity Disorder Rating Scale-Self Report: Short Version (CAARS-S:S) consists of 26 items rated from 0=not at all, never to 3=very much, very frequently. Four subscales each composed of 5 items (A: inattention/memory problems; B: hyperactivity/restlessness; C: impulsivity/emotional lability; and D: problems with self-concept) as well as a 12-item ADHD index can be computed. The raw scores were converted into standard T-scores. The higher T-scores represent a better or worse outcome. A T-score is a standard score with a mean of 50 and a standard deviation of 10 in all samples and across all scales
| score on a scale | Placebo | Low-dose | High-dose |
|---|---|---|---|
| Change From Baseline up to 8 Weeks Treat in the Conners' Adult Attention-Deficit/Hyperactivity Disorder Rating Scale-Self Report: Short Version (CAARS-S:S) ADHD Index of T-score. | -10.68 ± 11.27 | -7.43 ± 10.20 | -7.67 ± 9.56 |
Collected over 8 weeks. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Placebo | 0/22 (0%) | 0/22 (0%) | 4/22 (18.2%) |
| Low-dose | 0/23 (0%) | 0/23 (0%) | 6/23 (26.1%) |
| High-dose | 0/24 (0%) | 0/24 (0%) | 8/24 (33.3%) |
| Event | Placebo | Low-dose | High-dose |
|---|---|---|---|
| DIARRHOEAGastrointestinal disorders | 3/22 | 1/23 | 0/24 |
| COVID-19Infections and infestations | 0/22 | 2/23 | 3/24 |
| PALPITATIONSCardiac disorders | 2/22 | 0/23 | 1/24 |
| ABDOMINAL DISTENSIONGastrointestinal disorders | 1/22 | 2/23 | 1/24 |
| TACHYCARDIACardiac disorders | 0/22 | 0/23 | 2/24 |
| DRY MOUTHGastrointestinal disorders | 0/22 | 1/23 | 2/24 |
| HEADACHENervous system disorders | 0/22 | 0/23 | 2/24 |
| LETHARGYNervous system disorders | 0/22 | 0/23 | 2/24 |
| Age, Continuous(years) | Placebo | Low-dose | High-dose | Total |
|---|---|---|---|---|
| Mean | 29.3 ± 8.3 | 37.3 ± 10.2 | 33.3 ± 10.8 | 33.4 ± 10.2 |
| Sex: Female, Male(Participants) | Placebo | Low-dose | High-dose | Total |
|---|---|---|---|---|
| Female | 7 | 11 | 16 | 34 |
| Male | 15 | 12 | 8 | 35 |
| Race (NIH/OMB)(Participants) | Placebo | Low-dose | High-dose | Total |
|---|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 | 0 |
| Asian | 19 | 20 | 22 | 61 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 | 0 |
| Black or African American | 2 | 0 | 0 | 2 |
| White | 1 | 1 | 2 | 4 |
| More than one race | 0 | 2 | 0 | 2 |
| Unknown or Not Reported | 0 | 0 | 0 | 0 |
| Region of Enrollment(participants) | Placebo | Low-dose | High-dose | Total |
|---|---|---|---|---|
| United States | 3 | 3 | 3 | 9 |
| Taiwan | 19 | 20 | 21 | 60 |
| Weight(kg) | Placebo | Low-dose | High-dose | Total |
|---|---|---|---|---|
| Mean | 67.8 ± 13.7 | 72.0 ± 20.5 | 63.2 ± 11.1 | 67.6 ± 15.8 |
| Height(cm) | Placebo | Low-dose | High-dose | Total |
|---|---|---|---|---|
| Mean | 170.5 ± 8.2 | 167.8 ± 11.2 | 166.0 ± 8.3 | 168.0 ± 9.4 |
| BMI(kg/m2) | Placebo | Low-dose | High-dose | Total |
|---|---|---|---|---|
| Mean | 23.2 ± 3.6 | 25.2 ± 4.7 | 22.9 ± 3.0 | 23.7 ± 3.9 |
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Attention Deficit Disorder with Hyperactivity→
BioLite, Inc.