NCT03166215 is a Phase 1, PHASE2 clinical trial of TAK-935 in Developmental and/or Epileptic Encephalopathies, sponsored by Takeda.

Who is sponsoring NCT03166215?

NCT03166215 is sponsored by Takeda.

What drugs are being tested in NCT03166215?

Interventions in NCT03166215: TAK-935, Placebo.

What condition does NCT03166215 study?

NCT03166215 studies Developmental and/or Epileptic Encephalopathies.

Is NCT03166215 still recruiting?

NCT03166215 is currently completed. Last updated 7 January 2021.

Are results published for NCT03166215?

Yes — primary outcome results have been posted to ClinicalTrials.gov. See the outcomes section above for details.

Last reviewed 2021-01-07 · How we verify

NCT03166215

Name: Drug Landscape Pharmaceutical Database
Creator: Drug Landscape
Published: 2026-01-01
License: https://creativecommons.org/licenses/by/4.0/

Study of TAK-935 as an Adjunctive Therapy in Participants With Developmental and/or Epileptic Encephalopathies

Completed Phase 1, PHASE2 Results posted Last updated 7 January 2021

What this trial tests

Phase 1, PHASE2 trial testing TAK-935 in Developmental and/or Epileptic Encephalopathies in 18 participants. Completed in 19 September 2018.

Timeline

17 August 2017

Primary endpoint
19 September 2018

19 September 2018

Quick facts

Lead sponsor	Takeda
Phase	Phase 1, PHASE2
Status	Completed
Study type	INTERVENTIONAL
Allocation	randomized
Design	parallel
Masking	quadruple
Primary purpose	treatment
Enrollment	18
Start date	17 August 2017
Primary completion	19 September 2018
Estimated completion	19 September 2018
Sites	11 locations across United States

Drugs / interventions tested

TAK-935 — full drug profile →
Placebo

Conditions studied

Developmental and/or Epileptic Encephalopathies — all drugs for Developmental and/or Epileptic Encephalopathies →

Sponsor

Takeda — full company profile →

Who can join

Adults 18 to 65, any sex, with Developmental and/or Epileptic Encephalopathies. Patients with the condition only — healthy volunteers not accepted.

Results — posted to ClinicalTrials.gov

Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.

Percentage of Participants With at Least One Treatment-Emergent Adverse Event (TEAE), as Reported by the Participants or Participant's Caregivers or Observed by the Investigator, After TAK-935 Treatment Primary · From first dose up to 30 days post last dose (approximately up to 120 days)

An Adverse Event (AE) is defined as any untoward medical occurrence in a clinical investigation participant administered a drug; it does not necessarily have to have a causal relationship with this treatment. An AE can therefore be any unfavorable and unintended sign (eg, a clinically significant abnormal laboratory finding), symptom, or disease temporally associated with the use of a drug, whether or not it is considered related to the drug. A treatment-emergent adverse event (TEAE) is defined as an adverse event with an onset that occurs after receiving study drug

Group	Value	95% CI
Part 1: Placebo	100
Part 1: TAK-935	71.4
Part 2: TAK-935	68.8

Drug Clearance (CL) and Intercompartmental Clearance (Q) for TAK-935 Calculated Using the Observed Value of the Last Quantifiable Concentration Secondary · Day 1 pre-dose and at multiple timepoints (up to 5 hours) post-dose; Days 11 and 21 pre-dose and 1-hour post-dose; Days 31, 41, and 85 pre-dose

Group	Value	95% CI
TAK-935 100 mg BID	259.4	± 148.1
TAK-935 200 mg BID	195.8	± 116.3
TAK-935 300 mg BID	190	± 108.5

Group	Value	95% CI
TAK-935 100 mg BID	100.6	± 22.24
TAK-935 200 mg BID	70.99	± 14.6
TAK-935 300 mg BID	57.77	± 11.36

Apparent Volume of Distribution (Vz/F) of Central Compartment (Vc) and Peripheral Compartment (Vp) for TAK-935 Calculated Using the Observed Value of the Last Quantifiable Concentration Secondary · Day 1 pre-dose and at multiple timepoints (up to 5 hours) post-dose; Days 11 and 21 pre-dose and 1-hour post-dose; Days 31, 41, and 85 pre-dose

Group	Value	95% CI
TAK-935 100 mg BID	56.59	± 22.72
TAK-935 200 mg BID	60.51	± 23.79
TAK-935 300 mg BID	62	± 26.54

Group	Value	95% CI
TAK-935 100 mg BID	677.1	± 296.2
TAK-935 200 mg BID	474.3	± 201.9
TAK-935 300 mg BID	352.9	± 138.7

Absorption Rate Constant (Ka) for TAK-935 Secondary · Day 1 pre-dose and at multiple timepoints (up to 5 hours) post-dose; Days 11 and 21 pre-dose and 1-hour post-dose; Days 31, 41, and 85 pre-dose

Group	Value	95% CI
TAK-935 100 mg BID	2.13	± 0
TAK-935 200 mg BID	2.13	± 0
TAK-935 300 mg BID	2.13	± 0

Cmax,ss: Maximum Observed Plasma Concentration for TAK-935 at Steady State Secondary · Day 1 pre-dose and at multiple timepoints (up to 5 hours) post-dose; Days 11 and 21 pre-dose and 1-hour post-dose; Days 31, 41, and 85 pre-dose

Group	Value	95% CI
TAK-935 100 mg BID	269.6	± 159.6
TAK-935 200 mg BID	639.8	± 354.8
TAK-935 300 mg BID	975.3	± 411.5

AUC0-tau,ss: Area Under the Plasma Concentration-time Curve Over the Dosing Interval for TAK-935 at Steady State Secondary · Day 1 pre-dose and at multiple timepoints (up to 5 hours) post-dose; Days 11 and 21 pre-dose and 1-hour post-dose; Days 31, 41, and 85 pre-dose

Group	Value	95% CI
TAK-935 100 mg BID	562.5	± 406.8
TAK-935 200 mg BID	1437	± 909
TAK-935 300 mg BID	2188	± 1357

Cav,ss: Average Plasma Concentration During a Dosing Interval at Steady State for TAK-935 Secondary · Day 1 pre-dose and at multiple timepoints (up to 5 hours) post-dose; Days 11 and 21 pre-dose and 1-hour post-dose; Days 31, 41, and 85 pre-dose

Group	Value	95% CI
TAK-935 100 mg BID	46.9	± 33.9
TAK-935 200 mg BID	119.8	± 75.75
TAK-935 300 mg BID	182.3	± 113.1

Ctrough,ss: Plasma Concentration Immediately Prior to Dosing for TAK-935 at Steady State Secondary · Days 1, 11, 21; Days 31, 41 and 85 pre-dose

Group	Value	95% CI
TAK-935 100 mg BID	10.5	± 13.83
TAK-935 200 mg BID	26	± 29.2
TAK-935 300 mg BID	30.2	± 29.12

Percentage of Participants With at Least 1 Markedly Abnormal Value for Clinical Laboratory Evaluations After TAK-935 Secondary · From first dose up to last dose (up to Day 85)

Clinical Laboratory parameters: hematology, serum chemistry and urinalysis. Participants with at least 1 markedly abnormal values during treatment period were reported: Erythrocytes: \<0.8xLLN-\>1.5xULN, Hematocrit: \<0.8x LLN \>1.2xULN,Hemoglobin: \<0.8xLLN-\>1.2xULN Leukocytes: \<0.5xLLN, Platelets (10\^9/L): \<75x10\^9/L-\>600x10\^9/L, Prothrombin Ratio: \>1.5xULN, Alanine Aminotransferase: \>3xULN, Albumin:\<25 g/L, Alkaline Phosphatase: \>3xULN,Alpha-1 Acid Glycoprotein: \<47 mg/DL-\>125 mg/DL, Aspartate Aminotransferase:\>3xULN, Bicarbonate:\<8.0 mmol/L, Calcium:\<1.75 mmol/L-\>2.88 mmol

Alpha-1 Acid Glycoprotein (>125 mg/DL)

Group	Value	95% CI
Part 1: Placebo	0
Part 1: TAK-935	11.1
Part 2: TAK-935	14.3

Gamma Glutamyl Transferase ( >3 x ULN)

Group	Value	95% CI
Part 1: Placebo	0
Part 1: TAK-935	9.1
Part 2: TAK-935	6.7

HDL Cholesterol (<1.04 mmol/L)

Group	Value	95% CI
Part 1: Placebo	75.0
Part 1: TAK-935	18.2
Part 2: TAK-935	40.0

HDL Cholesterol (>1.55 mmol/L)

Group	Value	95% CI
Part 1: Placebo	0
Part 1: TAK-935	27.3
Part 2: TAK-935	13.3

LDL Cholesterol (>4.14 mmol/L)

Group	Value	95% CI
Part 1: Placebo	0
Part 1: TAK-935	9.1
Part 2: TAK-935	0

Potassium (>6.0 mmol/L)

Group	Value	95% CI
Part 1: Placebo	0
Part 1: TAK-935	9.1
Part 2: TAK-935	0

Percentage of Participants With at Least 1 Markedly Abnormal Value for Vital Signs After TAK-935 Secondary · From first dose up to 30 days post last dose (approximately up 120 days)

Vital signs included heart rate, blood pressure and body temperature. markedly abnormal values during treatment period were categorized as: heart rate 1,3 and 5 min standing (beats/min) \<50-\>120, systolic blood pressure 1,3 and 5 min standing (mmHg) \<85-\>180, diastolic blood pressure 1,3 and 5 min standing (mmHg) \<50-\>110 and body temperature (degree centigrade) \<35.6- \>37.7. Only categories with values have been reported.

Diastolic Blood Pressure 3 min Standing (<50 mmHg)

Group	Value	95% CI
Part 1: Placebo	33.3
Part 1: TAK-935	0
Part 2: TAK-935	0

Diastolic Blood Pressure 5 min Sitting (<50 mmHg)

Group	Value	95% CI
Part 1: Placebo	0
Part 1: TAK-935	7.1
Part 2: TAK-935	0

Diastolic Blood Pressure 5 min Supine (<50 mmHg)

Group	Value	95% CI
Part 1: Placebo	25.0
Part 1: TAK-935	0
Part 2: TAK-935	0

Heart Rate 1 min Standing (>120 beats/min)

Group	Value	95% CI
Part 1: Placebo	0
Part 1: TAK-935	16.7
Part 2: TAK-935	0

Heart Rate 5 min Sitting (<50 beats/min)

Group	Value	95% CI
Part 1: Placebo	50.0
Part 1: TAK-935	0
Part 2: TAK-935	6.3

Heart Rate 5 min Supine (<50 beats/min)

Group	Value	95% CI
Part 1: Placebo	25.0
Part 1: TAK-935	0
Part 2: TAK-935	0

Systolic Blood Pressure 5 min Sitting (<85 mmHg)

Group	Value	95% CI
Part 1: Placebo	0
Part 1: TAK-935	7.1
Part 2: TAK-935	0

Temperature (<35.6 C)

Group	Value	95% CI
Part 1: Placebo	25.0
Part 1: TAK-935	7.7
Part 2: TAK-935	18.8

Percentage of Participants With at Least 1 Markedly Abnormal Value for Electrocardiogram (ECG) Parameters After TAK-935 Secondary · From first dose up to last dose (up to Day 85)

A 12-lead ECG was performed. Markedly abnormal values during treatment period were categorized as: ECG ventricular rate \<50-\>120, PR Interval, (msec) \<=80-\>=200, QRS Duration, (msec) \<=80-\>=180, QT Interval, (msec) \<=50-\>=460, QTcF Interval, (msec) \<=50-\>=500 OR \>=30 change from baseline and \>=450 milliseconds, RR interval \<600-\>=1440.

ECG Ventricular Rate (<50 beats/min)

Group	Value	95% CI
Part 1: Placebo	33.3
Part 1: TAK-935	0
Part 2: TAK-935	0

QRS Duration (<=80 msec)

Group	Value	95% CI
Part 1: Placebo	0
Part 1: TAK-935	12.5
Part 2: TAK-935	6.7

RR Interval (<=600 msec)

Group	Value	95% CI
Part 1: Placebo	0
Part 1: TAK-935	0
Part 2: TAK-935	13.3

Adverse events — posted to ClinicalTrials.gov

Time frame: From first dose up to 30 days post last dose (approximately up to 120 days). Reporting threshold: 5%. Adverse-event reports describe events observed during the trial — not all are caused by the drug.

Part 1: Placebo

Serious: 0/4 (0%)

Deaths: 0/4

Part 1: TAK-935

Serious: 1/14 (7%)

Deaths: 0/14

Part 2: TAK-935

Serious: 3/16 (19%)

Deaths: 0/16

Serious adverse events (2 terms)

Reaction	System	Part 1: Placebo	Part 1: TAK-935	Part 2: TAK-935
Seizure Cluster	Nervous system disorders	—	—	—
Seizure	Nervous system disorders	—	—	—

Other adverse events (48 terms — click to expand)

Reaction	System	Part 1: Placebo	Part 1: TAK-935	Part 2: TAK-935
Insomnia	Psychiatric disorders	—	—	—
Dysarthria	Nervous system disorders	—	—	—
Seizure	Nervous system disorders	—	—	—
Upper respiratory tract infection	Infections and infestations	—	—	—
Headache	Nervous system disorders	—	—	—
Lethargy	Nervous system disorders	—	—	—
Fatigue	General disorders	—	—	—
Fall	Injury, poisoning and procedural complications	—	—	—
Bronchitis	Infections and infestations	—	—	—
Ear infection	Infections and infestations	—	—	—
Influenza	Infections and infestations	—	—	—
Rhinitis	Infections and infestations	—	—	—
Sinusitis	Infections and infestations	—	—	—
Decreased appetite	Metabolism and nutrition disorders	—	—	—
Agitation	Psychiatric disorders	—	—	—
Communication disorder	Psychiatric disorders	—	—	—
Irritability	Psychiatric disorders	—	—	—
Listless	Psychiatric disorders	—	—	—
Sleep talking	Psychiatric disorders	—	—	—
Tic	Psychiatric disorders	—	—	—
Balance disorder	Nervous system disorders	—	—	—
Somnolence	Nervous system disorders	—	—	—
Burning sensation	Nervous system disorders	—	—	—
Repetitive speech	Nervous system disorders	—	—	—
Sedation	Nervous system disorders	—	—	—
Tonic convulsion	Nervous system disorders	—	—	—
Haematoma	Vascular disorders	—	—	—
Cough	Respiratory, thoracic and mediastinal disorders	—	—	—
Wheezing	Respiratory, thoracic and mediastinal disorders	—	—	—
Vomiting	Gastrointestinal disorders	—	—	—
Constipation	Gastrointestinal disorders	—	—	—
Diarrhoea	Gastrointestinal disorders	—	—	—
Nausea	Gastrointestinal disorders	—	—	—
Rash	Skin and subcutaneous tissue disorders	—	—	—
Hyperhidrosis	Skin and subcutaneous tissue disorders	—	—	—
Arthralgia	Musculoskeletal and connective tissue disorders	—	—	—
Urinary incontinence	Renal and urinary disorders	—	—	—
Proteinuria	Renal and urinary disorders	—	—	—
Pyrexia	General disorders	—	—	—
Asthenia	General disorders	—	—	—

Most-reported serious reactions: Seizure Cluster, Seizure.

Data from ClinicalTrials.gov NCT03166215 adverse events section.

Sponsor's own description

The purpose of this study is to characterize the multiple-dose safety and tolerability profile of TAK-935 in adult participants with developmental and/or epileptic encephalopathies.

Publications & conference data

4 peer-reviewed publications reference this trial (live from Europe PMC):

Epileptic seizures.
Anwar H, Khan QU, Nadeem N, Pervaiz I, et al · · 2020 · cited 83× · PMID 32577498 · DOI 10.15190/d.2020.7
A phase 1b/2a study of soticlestat as adjunctive therapy in participants with developmental and/or epileptic encephalopathies.
Halford JJ, Sperling MR, Arkilo D, Asgharnejad M, et al · · 2021 · cited 40× · PMID 33940389 · DOI 10.1016/j.eplepsyres.2021.106646
Pharmacological diversity amongst approved and emerging antiseizure medications for the treatment of developmental and epileptic encephalopathies.
Sills GJ. · · 2023 · cited 19× · PMID 37655228 · DOI 10.1177/17562864231191000
Epilepsy Characteristics in Neurodevelopmental Disorders: Research from Patient Cohorts and Animal Models Focusing on Autism Spectrum Disorder.
Chakraborty S, Parayil R, Mishra S, Nongthomba U, et al · · 2022 · cited 18× · PMID 36142719 · DOI 10.3390/ijms231810807

Verify or expand the search:

Other trials of TAK-935

Trials testing the same drug.

NCT04461483 — A Study to Evaluate the Safety, Tolerability and Pharmacokinetics of Single Ascending Dose and Multiple Doses With Titra · Phase 1 · completed
NCT03650452 — A Phase 2, Multicenter, Randomized, Double-blind, Placebo-controlled Study to Evaluate the Efficacy, Safety, and Tolerab · Phase 2 · completed

Other Takeda trials

Trials by the same sponsor.

NCT05669729 — A Survey to Assess Participants', Caregivers', and Nurses' Use and Understanding of Educational Material on Velagluceras · not yet recruiting
NCT07403968 — A Study of Zasocitinib (TAK-279) in Adults With Active Crohn's Disease · Phase 2 · not yet recruiting
NCT07293364 — A Study to Learn About the C1-Inhibitor Function as Diagnosis for Hereditary Angioedema · NA · not yet recruiting
NCT07218393 — A Study About the Diagnosis and Management of Hereditary Angioedema (HAE) in Egypt · not yet recruiting
NCT07445087 — A Study of Takhzyro in Teenagers and Adults With Hereditary Angioedema (HAE) in South Korea · not yet recruiting

Verify against primary sources

ClinicalTrials.gov — authoritative US registry record
WHO ICTRP — international registry index
EU Clinical Trials Register
Sponsor press releases (Google)

Data sources for this page

Trial protocol + status: ClinicalTrials.gov NCT03166215 (US National Library of Medicine, public domain)
Publications: Europe PMC API search by NCT ID, retrieved 9 June 2026
Drug + disease cross-links: matched in real time against Drug Landscape's normalised drug + company + condition tables
Sponsor: as reported to ClinicalTrials.gov by Takeda
Last refreshed: 7 January 2021

Drug Landscape aggregates and links these public records for informational use only. Always verify against the primary source before clinical or regulatory decisions. Canonical URL: https://druglandscape.com/trial/NCT03166215.

Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing