NCT03406702: T-WAVE

CX-8998 for Absence Seizures

Completed Phase 2 Results posted Last updated 8 September 2022

What this trial tests

Phase 2 trial testing CX-8998 in Epilepsy in 7 participants. Completed in 29 March 2019.

Timeline

25 February 2018

Primary endpoint
29 March 2019

29 March 2019

Quick facts

Lead sponsor	Jazz Pharmaceuticals
Phase	Phase 2
Status	Completed
Study type	INTERVENTIONAL
Allocation	na
Design	single group
Masking	none
Primary purpose	treatment
Enrollment	7
Start date	25 February 2018
Primary completion	29 March 2019
Estimated completion	29 March 2019
Sites	7 locations across United States

Drugs / interventions tested

• CX-8998 — full drug profile →

Conditions studied

• Epilepsy — all drugs for Epilepsy →

Sponsor

Jazz Pharmaceuticals — full company profile →

Who can join

Adults 16 to 55, any sex, with Epilepsy. 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.

Change From Baseline to End of Treatment in QT Interval Corrected for Heart Rate Using Fridericia's Formula (QTcF) Primary · Baseline (Day 1) to end of treatment 1-2 hours post-dose, up to 4 weeks post-dose.

Fridericia's Correction Formula (QTCF) is a formula which takes into account the physiologic shortening of the QT interval which occurs as the heart rate increases, permitting comparison of the QT interval across a range of rates.

Group	Value	95% CI
CX-8998	3.50	± 10.213

Change From Baseline to End of Treatment in Clinical Alanine Aminotransferase Serum Chemistry Concentration Primary · Baseline (Day 1) to end of treatment, or up to 4 weeks post-dose.

Clinical safety laboratory assessment in alanine aminotransferase serum chemistry concentration.

Group	Value	95% CI
CX-8998	17.29	± 33.604

Change From Baseline to End of Treatment in Clinical Albumin Serum Chemistry Concentration Primary · Baseline (Day 1) to end of treatment, or up to 4 weeks post-dose.

Clinical safety laboratory assessment in albumin serum chemistry.

Group	Value	95% CI
CX-8998	-0.29	± 4.152

Change From Baseline to End of Treatment in Clinical Albumin/Globulin Serum Chemistry Concentration Primary · Baseline (Day 1) to end of treatment, or up to 4 weeks post-dose.

Clinical safety laboratory assessment in albumin/globulin serum chemistry.

Group	Value	95% CI
CX-8998	-0.15	± 0.212

Change From Baseline to End of Treatment in Clinical Alkaline Phosphatase Serum Chemistry Concentration Primary · Baseline (Day 1) to end of treatment, or up to 4 weeks post-dose.

Clinical safety laboratory assessment in alkaline phosphatase serum chemistry.

Group	Value	95% CI
CX-8998	3.14	± 10.399

Change From Baseline to End of Treatment in Clinical Aspartate Aminotransferase Serum Chemistry Concentration Primary · Baseline (Day 1) to end of treatment, or up to 4 weeks post-dose.

Clinical safety laboratory assessment in aspartate aminotransferase serum chemistry.

Group	Value	95% CI
CX-8998	27.71	± 60.810

Baseline Clinical Blood Urea Nitrogen/Creatinine Serum Chemistry Concentration Primary · Baseline (Day 1)

Clinical safety laboratory assessment in BUN/Creatinine serum chemistry.

Group	Value	95% CI
CX-8998	12.70	± NA

Change From Baseline to End of Treatment in Clinical Bilirubin Serum Chemistry Concentration Primary · Baseline (Day 1) to end of treatment, or up to 4 weeks post-dose.

Clinical safety laboratory assessment in bilirubin serum chemistry.

Group	Value	95% CI
CX-8998	-0.55	± 2.577

Change From Baseline to End of Treatment in Clinical Blood Urea Nitrogen Serum Chemistry Concentration Primary · Baseline (Day 1) to end of treatment, or up to 4 weeks post-dose.

Clinical safety laboratory assessment in blood urea nitrogen serum chemistry.

Group	Value	95% CI
CX-8998	0.23	± 1.254

Change From Baseline to End of Treatment in Clinical Carbon Dioxide Serum Chemistry Concentration Primary · Baseline (Day 1) to end of treatment, or up to 4 weeks post-dose.

Clinical safety laboratory assessment in carbon dioxide serum chemistry.

Group	Value	95% CI
CX-8998	0.43	± 2.936

Change From Baseline to End of Treatment in Clinical Chloride Serum Chemistry Concentration Primary · Baseline (Day 1) to end of treatment, or up to 4 weeks post-dose.

Clinical safety laboratory assessment in chloride serum chemistry.

Group	Value	95% CI
CX-8998	-0.86	± 3.716

Change From Baseline to End of Treatment in Clinical Calcium Serum Chemistry Concentration Primary · Baseline (Day 1) to end of treatment, or up to 4 weeks post-dose.

Clinical safety laboratory assessment in calcium serum chemistry.

Group	Value	95% CI
CX-8998	-0.01	± 0.109

Adverse events — posted to ClinicalTrials.gov

Time frame: Adverse events (AEs) were collected from Day 1 up to Day 26 post-dose, or up to 1 year 3 weeks.. Reporting threshold: 5%. Adverse-event reports describe events observed during the trial — not all are caused by the drug.

CX-8998 Days 1 - 2 (4 mg/d)

Serious: 0/7 (0%)

Deaths: 0/7

CX-8998 Days 3 - 8 (8 mg/d)

Serious: 0/5 (0%)

Deaths: 0/5

CX-8998 Days 9 - 14 (12 mg/d)

Serious: 0/6 (0%)

Deaths: 0/6

CX-8998 Days 15 - 20 (16 mg/d)

Serious: 0/6 (0%)

Deaths: 0/6

CX-8998 Days 21 - 27 (20 mg/d)

Serious: 0/6 (0%)

Deaths: 0/6

Other adverse events (9 terms — click to expand)

Reaction	System	CX-8998 Days 1 - 2 (4 mg/d)	CX-8998 Days 3 - 8 (8 mg/d)	CX-8998 Days 9 - 14 (12 mg…	CX-8998 Days 15 - 20 (16 m…	CX-8998 Days 21 - 27 (20 m…
Palpitations	Cardiac disorders	—	—	—	—	—
Visual impairment	Eye disorders	—	—	—	—	—
Dry mouth	Gastrointestinal disorders	—	—	—	—	—
Nausea	Gastrointestinal disorders	—	—	—	—	—
Sluggishness	General disorders	—	—	—	—	—
Seizure	Nervous system disorders	—	—	—	—	—
Headache	Nervous system disorders	—	—	—	—	—
Lethargy	Nervous system disorders	—	—	—	—	—
Euphoric mood	Psychiatric disorders	—	—	—	—	—

Data from ClinicalTrials.gov NCT03406702 adverse events section.

Sponsor's own description

This is a Phase 2a, open-label study consisting of a screening period of up to 4 weeks and a 4-dose-titration treatment period to a dose of up to 10 mg twice daily (BID) of CX-8998, followed by a 1-week safety follow-up period after the last dose of study medication.

Publications & conference data

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

1. Clinical and experimental insight into pathophysiology, comorbidity and therapy of absence seizures.
   Crunelli V, Lőrincz ML, McCafferty C, Lambert RC, et al · · 2020 · cited 132× · PMID 32437558 · DOI 10.1093/brain/awaa072
2. 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
3. Potassium and calcium channels in different nerve cells act as therapeutic targets in neurological disorders.
   Qiu Q, Yang M, Gong D, Liang H, et al · · 2025 · cited 11× · PMID 38845230 · DOI 10.4103/nrr.nrr-d-23-01766