Diabetic Peripheral NeuropathyPhase 4OPTIMUMNCT04846673

Pregabalin and Alpha-lipoic Acid Combination Versus Each Monotherapy in Patients With Diabetic Peripheral Neuropathy

A Phase 4 study testing Pregabalin 150mg + Alpha-lipoic acid 480mg, Pregabalin 150mg and Alpha-Lipoic Acid 480mg in people with Diabetic Peripheral Neuropathy, run by Yuhan Corporation at 14 sites in South Korea.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record

Search all trials

Trial summary

This study is a randomized, parallel, open-label, multicenter, phase IV clinical trial to assess the efficacy and safety of pregabalin and alpha-lipoic acid combination compared with each monotherapy in patients with diabetic peripheral neuropathy for 12 weeks. Read more about this study

Who is it for?: Ages 19 to 75 years
Conditions the study is for: Diabetic Peripheral Neuropathy
What is being tested?: Pregabalin 150mg + Alpha-lipoic acid 480mg, Pregabalin 150mg and Alpha-Lipoic Acid 480mg
Type of treatment: Pill or oral medicine
Could I receive a placebo?: No, everyone receives an active treatment
How many people: 151 participants
Where: 14 sitesSouth Korea
Study dates: 14 May 2021to 30 Nov 2022
Phase: Phase 4
Are there results?: None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

Ages 19 to 75 years
All sexes
No healthy volunteers
Adult, Older adult

Who may be able to join

aged 19 to 75
type 2 diabetes mellitus with HbA1c (Hemoglobin A1c) ≤ 10 %
peripheral (eg. hands, feet) neuropathic pain (eg. abnormal sensations, numbness, pain, etc.) within 3 months (12 weeks)
diagnosed with diabetic peripheral neuropathy (DPN)
VAS pain score ≥ 40 mm
written informed consent

Who cannot join

brittle diabetes mellitus
ALT (Alanine Transaminase), AST (Aspartate Transaminase), CPK (Creatine Phosphokinase) level ≥ 3 times the upper limit of normal (UNL) or active liver disease
severe renal impairment (eGFR (estimated glomerular filtration rate) < 60 mL/min/ 1.73m2)
treated with antiepileptic drugs within 1 week at randomization
other nervous system or neuropathic disorders that may affect pain evaluation
oral drug administration is not possible, or hypersensitive or allergic to pregabalin, r-thioctic acid tromethamine, thioctic acid, and other excipients

Show all 9Show fewer

pregnant, lactating, or childbearing potential
alcoholics, drug abusers, and patients who are difficult to participate in clinical trials due to psychological and emotional problems
have participated in other clinical trials within 30 days at screening

Trial locations and contacts

14 sites in 1 country.

City, postcode or hospital

14 sites in 1 country

South Korea14 sites

Pusan National University Hospital
Busan
Chosun University Hospital, School of Medicine, Chosun University
Gwangju
Dongtan Sacred Heart Hospital, Hallym University College of Medicine
Gyeonggi-do
Seoul National University Bundang Hospital
Gyeonggi-do
The Catholic University of Korea, Incheon ST. Mary's Hospital
Incheon
Jeju National University College of Medicine
Jeju City
Jeonbuk National University Hospital
Jeollabuk-do
Asan Medical Center, University of Ulsan College of Medicine
Seoul
Inje University Sanggye Paik Hospital
Seoul
Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine
Seoul
Korea University Guro Hospital
Seoul
Seoul St.Mary's Hospital, The Catholic University of Korea
Seoul
Yeouido St. Mary's Hospital, The Catholic University of Korea
Seoul
Ulsan University Hospital, College of Medicine University of Ulsan
Ulsan

Other trials in South Korea

About this study

Official title: Efficacy and Safety of Pregabalin and Alpha-lipoic Acid Combination Versus Each Monotherapy in Patients With Diabetic Peripheral Neuropathy: a Randomized, Parallel, Open-label, Multicenter, Phase IV Clinical Trial (OPTIMUM Trial)

Conditions: Diabetic Peripheral Neuropathy
Being tested: Pregabalin 150mg + Alpha-lipoic acid 480mg, Pregabalin 150mg, Alpha-Lipoic Acid 480mg

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

Pregabalin 150mg + Alpha-lipoic acid 480mgDrug
Pregabalin qd + alpha-lipoic acid qd
Pregabalin 150mgDrug
pregabalin qd
Alpha-Lipoic Acid 480mgDrug
alpha-lipoic acid qd

Study groups in NCT04846673
Study group	Role	What they receive
Pregabalin and alpha-lipoic acid combination therapy	Experimental	Alpha-lipoic acid 480 mg/tablet once daily before breakfast and Pregabalin 150 mg/tablet once daily before bedtime will be administrated for 12 weeks. Receives: Drug: Pregabalin 150mg + Alpha-lipoic acid 480mg
Pregabalin monotherapy	Experimental	Pregabalin 150 mg/tablet once daily before bedtime will be administrated for 12 weeks. Receives: Drug: Pregabalin 150mg
Alpha-lipoic acid monotherapy	Active comparator	Alpha-lipoic acid 480 mg/tablet once daily before breakfast will be administrated for 12 weeks. Receives: Drug: Alpha-Lipoic Acid 480mg

What is being measured

The primary outcome is the main question the study is designed to answer.

visual analogue scale (VAS)
Measured: 12 weeks

Secondary outcomes (7)

visual analogue scale (VAS)
Measured: 6 weeks
visual analogue scale (VAS) reduction rate of more than 30%
Measured: 6 weeks, 12 weeks
visual analogue scale (VAS) reduction rate of more than 50%
Measured: 6 weeks, 12 weeks
brief pain inventory Korean version, BPI-K
Measured: 6 weeks, 12 weeks
total symptom score, TSS
Measured: 6 weeks, 12 weeks
pain detect questionnaire, PD-Q
Measured: 6 weeks, 12 weeks
3 level version of Euro-Qol-5 dimensions, EQ-5D-3L
Measured: 6 weeks, 12 weeks

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

14 May 202130 Nov 2022

First posted15 Apr 2021
Study start14 May 2021
Primary completion30 Nov 2022
Study completion30 Nov 2022

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Publications (1)Papers the sponsor has linked to this study.
Other trials for Diabetic Peripheral NeuropathyStudies of the same condition, open and under way.
More trials run by Yuhan CorporationThe sponsor's other registered studies.
What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design

Study type: Interventional
Phase: Phase 4
Primary purpose: Treatment
Allocation: Randomised
Intervention model: Parallel groups
Masking: None (open label)
Enrolment: 151 participants (actual)

IDs, dates and publications

ClinicalTrials.gov ID: NCT04846673
Sponsor's protocol ID: YMC045
Acronym: OPTIMUM
Status last verified: Mar 2025
First submitted: 13 Apr 2021
Last updated: 3 Apr 2025
Results posted: No
Data monitoring committee: No
FDA-regulated drug: No
FDA-regulated device: No

Publications

Oh TJ, Kim SS, Lee SH, Kwon HS, Kim ES, Rhee EJ, Yoo HJ, Jang HN, Lee WJ, Kim ES, Kim SY, Koh G, Hong EG, Park TS, Won JC. Efficacy and Safety of Pregabalin and Alpha-Lipoic Acid Combination in Patients With Painful Diabetic Peripheral Neuropathy: A Randomized, Open-Label, Non-Inferiority, Phase IV Clinical Trial and Subgroup Analysis (OPTIMUM Study). Diabetes Obes Metab. 2026 Jul;28(7):6172-6183. doi: 10.1111/dom.70795. Epub 2026 Apr 29.
PubMed 42056717

Want to know more?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

See locations

Active, not recruiting
Wearable Insoles for Recurrent Diabetic Ulcer Prevention
Diabetes, Peripheral Neuropathy
Recruiting
Effect of 4-7-8 Breathing Technique on Pain and Anxiety During Electromyography in Diabetic Neuropathy
Diabetic Neuropathies, Diabetes Mellitus (Type 2)
Active, not recruiting
Comparative Effects Of Sensory Reweighting And Proprioceptive Facilitation Training On Balance And Fall Risk In Diabetic Peripheral Neuropathy
Diabetic Peripheral Neuropathy (DPN)
Not yet recruiting
Adaptive Gamified Sensory Training on Sensory Function and Limb-Specific Functional Performance in Patients With Diabetic Peripheral Neuropathy
Diabetic Peripheral Neuropathy
Active, not recruiting
Comparative Effects of tDCS and tACS on Pain, Dexterity, and Strength in Diabetic Peripheral Neuropathy
Diabetic Peripheral Neuropathy (DPN)

All Diabetic Peripheral Neuropathy trials

Study at a glance

From the registry record, last updated by the sponsor on 3 Apr 2025. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: Efficacy and Safety of Pregabalin and Alpha-lipoic Acid Combination Versus Each Monotherapy in Patients With Diabetic Peripheral Neuropathy: a Randomized, Parallel, Open-label, Multicenter, Phase IV Clinical Trial (OPTIMUM Trial)
ClinicalTrials.gov ID: NCT04846673
Acronym / sponsor ID: OPTIMUM / YMC045
Conditions: Diabetic Peripheral Neuropathy
Phase: Phase 4
Study type: Interventional
Recruitment status: Completed
Enrolment: 151 participants (actual)
Lead sponsor: Yuhan CorporationIndustry (pharma, biotech, devices)
Study start: 14 May 2021 (actual)
Primary completion: 30 Nov 2022 (actual)
Study completion: 30 Nov 2022 (actual)
First posted: 15 Apr 2021 (actual)
Results: Not posted in the source record

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

Study design

Primary purpose: Treatment
Allocation: Randomised
Intervention model: Parallel groups
Masking: None (open label)
Number of arms: 3

Arm	Type	Receives
Pregabalin and alpha-lipoic acid combination therapy	Experimental	Drug: Pregabalin 150mg + Alpha-lipoic acid 480mgAlpha-lipoic acid 480 mg/tablet once daily before breakfast and Pregabalin 150 mg/tablet once daily before bedtime will be administrated for 12 weeks.
Pregabalin monotherapy	Experimental	Drug: Pregabalin 150mgPregabalin 150 mg/tablet once daily before bedtime will be administrated for 12 weeks.
Alpha-lipoic acid monotherapy	Active comparator	Drug: Alpha-Lipoic Acid 480mgAlpha-lipoic acid 480 mg/tablet once daily before breakfast will be administrated for 12 weeks.

Who may qualify

Ages: 19 to 75 years
Sex: All
Healthy volunteers: Not accepted
Age groups: Adult, Older adult

Key inclusion criteria (6 listed)

aged 19 to 75
type 2 diabetes mellitus with HbA1c (Hemoglobin A1c) ≤ 10 %
peripheral (eg. hands, feet) neuropathic pain (eg. abnormal sensations, numbness, pain, etc.) within 3 months (12 weeks)
diagnosed with diabetic peripheral neuropathy (DPN)
VAS pain score ≥ 40 mm

Key exclusion criteria (9 listed)

brittle diabetes mellitus
ALT (Alanine Transaminase), AST (Aspartate Transaminase), CPK (Creatine Phosphokinase) level ≥ 3 times the upper limit of normal (UNL) or active liver disease
severe renal impairment (eGFR (estimated glomerular filtration rate) < 60 mL/min/ 1.73m2)
treated with antiepileptic drugs within 1 week at randomization
other nervous system or neuropathic disorders that may affect pain evaluation

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
Pregabalin 150mg + Alpha-lipoic acid 480mgPregabalin qd + alpha-lipoic acid qd	Drug	Pregabalin and alpha-lipoic acid combination therapy
Pregabalin 150mgpregabalin qd	Drug	Pregabalin monotherapy
Alpha-Lipoic Acid 480mgalpha-lipoic acid qd	Drug	Alpha-lipoic acid monotherapy

Primary outcome

visual analogue scale (VAS)
Time frame: 12 weeks

7 secondary outcomes

visual analogue scale (VAS)
Time frame: 6 weeks
visual analogue scale (VAS) reduction rate of more than 30%
Time frame: 6 weeks, 12 weeks
visual analogue scale (VAS) reduction rate of more than 50%
Time frame: 6 weeks, 12 weeks
brief pain inventory Korean version, BPI-K
Time frame: 6 weeks, 12 weeks
total symptom score, TSS
Time frame: 6 weeks, 12 weeks
pain detect questionnaire, PD-Q
Time frame: 6 weeks, 12 weeks
3 level version of Euro-Qol-5 dimensions, EQ-5D-3L
Time frame: 6 weeks, 12 weeks

Results and safety

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 3 Apr 2025.
Derived from this study: PubMed 42056717Oh TJ, Kim SS, Lee SH, Kwon HS, Kim ES, Rhee EJ, Yoo HJ, Jang HN, Lee WJ, Kim ES, Kim SY, Koh G, Hong EG, Park TS, Won JC. Efficacy and Safety of Pregabalin and Alpha-Lipoic Acid Combination in Patients With Painful Diabetic Peripheral Neuropathy: A Randomized, Open-Label, Non-Inferiority, Phase IV Clinical Trial and Subgroup Analysis (OPTIMUM Study). Diabetes Obes Metab. 2026 Jul;28(7):6172-6183. doi: 10.1111/dom.70795. Epub 2026 Apr 29.

Related trials for Diabetic Peripheral Neuropathy

Active, not recruiting
Wearable Insoles for Recurrent Diabetic Ulcer Prevention
Diabetes, Peripheral Neuropathy
Recruiting
Effect of 4-7-8 Breathing Technique on Pain and Anxiety During Electromyography in Diabetic Neuropathy
Diabetic Neuropathies, Diabetes Mellitus (Type 2)
Active, not recruiting
Comparative Effects Of Sensory Reweighting And Proprioceptive Facilitation Training On Balance And Fall Risk In Diabetic Peripheral Neuropathy
Diabetic Peripheral Neuropathy (DPN)
Not yet recruiting
Adaptive Gamified Sensory Training on Sensory Function and Limb-Specific Functional Performance in Patients With Diabetic Peripheral Neuropathy
Diabetic Peripheral Neuropathy
Active, not recruiting
Comparative Effects of tDCS and tACS on Pain, Dexterity, and Strength in Diabetic Peripheral Neuropathy
Diabetic Peripheral Neuropathy (DPN)

Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.

Jongchul Won principal investigator

Inje University

14 sites in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 6 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 3 Apr 2025. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 14 sites in South Korea. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

visual analogue scale (VAS) (time frame: 12 weeks). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT04846673, which also lists 1 linked publication.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 3 Apr 2025.