ClinicalTrials.gg
RecruitingNCT07712913PRISEUpdated Jul 20, 2026

Extended-release Pregabalin for the Treatment of Neuropathic Pain in Patients With Diabetic Peripheral Neuropathy and Postherpetic Neuralgia

A Phase 3 interventional study of Experimental: Pregabalin XR and Comparator: Dorene Tabs in Diabetic Neuropathy, Neuropathic Pain and Neuralgia, Postherpetic, sponsored by Brainfarma Industria Química e Farmacêutica S/A. Recruiting at 15 sites in Brazil. Open to participants aged 18 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-07-20.

Sponsored by Brainfarma Industria Química e Farmacêutica S/A (part of Hypera Pharma) · Phase 3, Interventional, and Treatment

From the registry’s dates

  • Started Jun 2026; still recruiting 4 months later.
Phase
Phase 3
Study type
Interventional
Enrollment
348
Allocation
Randomized
Ages
18 Years to 75 Years
Sex
All
01

Study summary

Extended-release Pregabalin for the Treatment of Neuropathic Pain in Patients With Diabetic Peripheral Neuropathy and Postherpetic Neuralgia

02

Conditions studied

  • Diabetic Neuropathy
  • Neuropathic Pain
  • Neuralgia, Postherpetic

Keywords

  • multicenter
  • randomized
  • double-blind
  • double-dummy
  • controlled
  • parallel-group
  • non-inferiority
  • diabetic
  • postherpetic neuralgia
  • peripheral neuropathy
  • Pregabalin
03

In context

Diabetic Neuropathies

538 studies on the registry are indexed under Diabetic Neuropathies; 80 are open to participants now.

This study's planned enrollment of 348 is above the median of 68 across 448 interventional studies indexed under Diabetic Neuropathies.

Browse Diabetic Neuropathies studies →

Lead sponsor

Brainfarma Industria Química e Farmacêutica S/A is the lead sponsor of 15 studies on the registry; 7 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 75 Years
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

The following criteria must be met for a participant to be included in the study:

  1. Participants of either sex, aged 18 to 75 years.
  2. Be able to understand and agree to participate in the study, undergo the procedures, and attend the visits, as indicated by signing the form approved by the CEP/Conep System.
  3. Have a diagnosis of peripheral neuropathic pain associated with:

    • diabetes mellitus (type 1 or 2), with (HbA1c) levels ≤ 11%, documented symptoms of peripheral diabetic neuropathy for at least 6 months, and use of medication for glycemic control at a stable dose for at least 30 days.
    • postherpetic neuralgia, with pain symptoms for at least 3 months following a skin rash due to an acute episode of herpes zoster.
  4. Presence of neuropathic pain, with an intensity of ≥ 4 on the 11-point DPRS numerical scale (from 0 "no pain" to 10 "worst possible pain"‡). ‡ Pain intensity ≥ 4 will be confirmed at the initial visit (IV); during the screening/randomization visit, Participant Diary No. 1 containing the DPRS scales will be provided, in which the participant will record pain intensity daily upon waking and at the end of the day for 7 days (±2 days). The mean value for pain intensity recorded during the Screening/Randomization Phase will be used to confirm eligibility at the initial visit (IV).
  5. Participants who are unable to become pregnant ( women, defined as 12 months or more of amenorrhea, or who have undergone surgical sterilization*; and men who have undergone vasectomy**) OR participants of who agree to use a reliable method of ***.

    • Female sterilization (undergoing bilateral surgical oophorectomy with or without hysterectomy), total hysterectomy, or tubal ligation at least 6 weeks prior to administration of the drug.

      • Male sterilization at least 6 months prior to screening. *** If the participant is of childbearing age and decides to participate in the study, they must use or request that their partner use a safe contraceptive method. A safe contraceptive method is defined as the use of at least one of the following: condoms, a diaphragm, and/or a hormonal method (estrogenic and/or progestogenic) in the form of medication, including oral, vaginal, injectable, transdermal, and intrauterine devices. Only participants who expressly declare themselves exempt from the risk of pregnancy-whether because they do not engage in sexual activity or because they engage in it in a non-reproductive manner-will have the right to participate in the study without the mandatory use of contraceptives. Examples include participants who have undergone a vasectomy, those with an infertile partner, or those practicing total heterosexual abstinence.

The decision regarding the best contraceptive method to use will be made jointly by the physician and the study participant. If there are any costs involved, the chosen contraceptive method will be provided by the sponsor free of charge for as long as necessary. In addition, condoms with spermicide will be provided to participants at all study visits, when applicable.

Exclusion criteria

Exclusion Criteria:

A positive response to any of the following criteria will exclude the participant from the study:

  1. The presence of pain unrelated to the primary diagnosis of diabetic peripheral neuropathy or postherpetic neuralgia that could interfere with the evaluation.
  2. Any skin condition that potentially alters sensation in the affected dermatome or area of neuropathic involvement, which could interfere with the assessment.
  3. Having undergone neurosurgical therapy for the treatment of neuropathy.
  4. Current use, or use within the past 7 days, of nerve block therapy and/or medications commonly used to treat neuropathic pain (e.g., benzodiazepines, skeletal muscle relaxants, capsaicin, local anesthetics, opioids, memantine), antiepileptic drugs (e.g., carbamazepine, clonazepam, phenytoin, valproic acid, lamotrigine, topiramate, gabapentin), antidepressants (e.g., tricyclics, serotonin reuptake inhibitors, venlafaxine), and potential neurotoxins (e.g., hydroxychloroquine, deferoxamine, thioridazine, vigabatrin).
  5. History of treatment failure or to pregabalin or gabapentin.
  6. History of neoplastic disease within the past 2 years (excluding basal cell carcinoma), neurological disease, unstable heart disease, psychiatric conditions (particularly suicidal ideation), and/or infection with , , or .
  7. Current laboratory abnormalities in liver enzymes (elevated and/or ALT 2.5 times the upper limit of the reference range) and/or renal insufficiency ( \< 60 mL/min/1.73 m²).
  8. History of illicit drug abuse in the past 2 years.
  9. History of alcoholism (average alcohol intake exceeding 3 standard drinks* per day or more than 7 standard drinks per week for women, and exceeding 4 standard drinks per day or more than 14 standard drinks per week for men) in the past 2 years.

    * A standard drink is: a can of regular beer (330 mL at 4%); a shot of distilled spirits (30 mL at 40%); a glass of wine or a small glass of sherry (100 mL at 12% or 70 mL at 18%); a small glass of liqueur or similar (50 mL at 25%) (53).

  10. Being pregnant, breastfeeding, or intending to become pregnant during the study period.
  11. Having participated in clinical studies in the past 12 (twelve) months, unless there may be a direct benefit to the study participant, at the investigator's discretion.
  12. Having any condition that prevents participation, at the investigator's discretion.
Terms in these criteria, in plain language(12)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

HbA1c

A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.

Postmenopausal

Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).

Reproductive potential

Able to have children. For women this usually means from the first period until menopause, unless permanently unable to through surgery; for men, unless permanently sterile. Read who the line is about — participants, women, men, or their partners.

Criteria about it usually ask for contraception during the study and for a time after it.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

Investigational drug or device

A drug or device being studied in a clinical trial.

It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.

Hypersensitivity

An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.

Hepatitis B tests

Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.

Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.

Hepatitis C tests

Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.

After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.

HIV

The human immunodeficiency virus, which weakens the immune system.

Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.

ALT and AST (liver enzymes)

Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.

Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.

GFR and eGFR (kidney filtering)

GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².

Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.

05

Study design

Phase
Phase 3
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Double (Participant, Investigator)
Enrollment
348 participants (estimated)

Study arms

  • Experimental
    Pregabalin XR: Extended-release pregabalin

    Pregabalin XR: will receive extended-release pregabalin tablets at an initial dose of 82.5 mg once daily (during the first week for titration). The dose may be adjusted every 7 days during the first 4 weeks of treatment, up to a maximum of 660 mg once daily. In addition, the experimental group may receive a placebo twice daily.

    Drug: Experimental: Pregabalin XR · Drug: experimental placebo

  • Active comparator
    Dorene Tabs: Immediate-release pregabalin

    Dorene Tabs: will receive immediate-release pregabalin tablets (Dorene Tabs) at a starting dose of 75 mg twice daily. The dose may be adjusted every 7 days during the first 4 weeks of treatment, up to a maximum of 300 mg twice daily. In addition, the comparison group will receive a placebo once daily.

    Drug: Comparator: Dorene Tabs · Drug: Comparator placebo

Interventions

  • Pregabalin XR: extended-release tablet, with an initial dose of 82.5 mg once daily. The dose may be adjusted every 7 days during the first 4 weeks of treatment, up to a maximum of 660 mg once daily. In addition, the experimental group will receive a placebo twice daily.

  • DrugComparator: Dorene Tabs

    Pregabalin immediate-release tablets, at an initial dose of 75 mg twice daily. The dose may be adjusted every 7 days during the first 4 weeks of treatment, up to a maximum of 300 mg twice daily. In addition, the comparator group will receive a placebo once daily.

  • DrugComparator placebo

    Comparator placebo

  • Drugexperimental placebo

    experimental placebo

06

What researchers measure

Primary outcomes

  1. Difference in the mean pain intensity score 16 weeks after the start of treatment, compared to baseline

    Difference in the mean pain intensity score 16 weeks after the start of treatment, compared to baseline, between the study drug and the comparator, as measured by the 11-point DPRS (Daily Pain Rating Scale) (ranging from 0 "no pain" to 10 "worst possible pain"). Participants completed the baseline scale at the research center and filled it out daily at home until visit V8, twice a day. The average number of scales will be calculated by dividing the number of scales completed by the number of days on which they were completed.

    Time frame: 16 weeks

Secondary outcomes

  1. To assess improvement in neuropathic pain during treatment.

    Difference in the mean pain intensity score at 1, 4, 8, and 12 weeks after the start of treatment, compared to baseline, between the experimental drug and the comparator, as measured by the 11-point DPRS scale.

    Time frame: 1 to 12 weeks

  2. To assess the proportion of participants who experienced significant improvement in neuropathic pain during and at the end of treatment.

    Difference in the mean total pain score at 1, 4, 8, 12, and 16 weeks after the start of treatment, compared to baseline, between the experimental drug and the comparator, as measured by the SF-MPQ (Short Form - McGill Pain Questionnaire).

    Time frame: 1 to 16 weeks

  3. To assess improvements in the impact of neuropathic pain on sleep, quality of life, and symptoms of anxiety and depression during and at the end of treatment.

    Proportion of participants with a ≥ 30% reduction in pain intensity at 1, 4, 8, 12, and 16 weeks after the start of treatment, compared to baseline, between the study drug and the comparator, as measured by the 11-point DPRS scale. Difference in the mean score for pain interference with sleep at 4, 8, 12, and 16 weeks after the start of treatment, relative to baseline, between the study drug and the comparator, as measured by the 11-point DSIS (Daily Sleep Interference Scale) (ranging from 0 "pain did not interfere with sleep" to 10 "pain completely interfered with sleep"). Difference in quality of life at 4, 8, 12, and 16 weeks after the start of treatment, compared to baseline, between the experimental drug and the comparator, as measured by the WHOQoL-BREF (World Health Organization Quality of Life Scale). Difference in anxiety and depression symptoms at 4, 8, 12, and 16 weeks after the start of treatment, compared to baseline, between the experimental drug and the comparator.

    Time frame: 1 to 16 weeks

  4. Assess the participant's overall perception of change at the end of treatment.

    Proportion of participants who rated their clinical condition as "much better," "moderately better," "slightly better," "no change," "slightly worse," "moderately worse," and "much worse," using the PGIC (Patient Global Impression of Change) scale, when comparing the experimental drug to the comparator 16 weeks after the start of treatment.

    Time frame: Week 16

  5. Evaluate the use of rescue medication.

    Proportion of participants who used rescue medication, frequency of use, dose, and duration, comparing the experimental medication with the comparator.

    Time frame: 1 to 16 weeks.

Other outcomes

  1. Safety Outcome: To evaluate the safety of extended-release pregabalin tablets compared with immediate-release pregabalin tablets in participants with diabetic neuropathy or postherpetic neuralgia.

    Incidence rate of serious and non-serious adverse events-both related and unrelated-by treatment group throughout the clinical trial, based on an analysis of data obtained from clinical and physical examinations and laboratory tests.

    Time frame: 19 weeks.

07

Study locations

15 of 15 sites recruiting
  • Cpec Obras Sociais Irmã Dulce
    Salvador, Estado de Bahia 41680430, Brazil
    Recruiting
  • Instituto Anima de Extensão Universitária - Unibh
    Belo Horizonte, Minas Gerais 30575180, Brazil
    Recruiting
  • Centro de Ensino Superior de Vespasiano
    Vespasiano, Minas Gerais 33200664, Brazil
    Recruiting
  • Instituto Estadual Do Cerebro Paulo Niemeyer
    Rio de Janeiro, Rio de Janeiro 20231092, Brazil
    Recruiting
    • Charles R Seixas · Contactcharleseixas.cpc@gmail.com · 5521967075993
    • Luiz E. A. Wildemberg, Endocrinologist · Principal investigator
  • Apec Sociedade Potiguar de Educação E Cultura
    Natal, Rio Grande do Norte 59076000, Brazil
    Recruiting
  • Clinica Neurologica E Neurocirurgica de Joinville
    Joinville, Santa Catarina 89202190, Brazil
    Recruiting
  • Instituto Anima de Extensão Universitária - Unisul
    Palhoça, Santa Catarina 88137270, Brazil
    Recruiting
  • Fundação de Beneficência Hospital de Cirurgia
    Aracaju, Sergipe 49055480, Brazil
    Recruiting
    • Katiane Soares Research Center Manager · Contactkatiane.soares@newdatatrials.com · 5511970306077
    • Alex V. C. França, Gastroenterologist · Principal investigator
  • Associação Aracajuana Hospital Santa Isabel
    Aracaju, Sergipe 49072720, Brazil
    Recruiting
    • Katiane Soares Research Center Manager · Contactkatiane.soares@newdatatrials.com · 5511970306077
    • Alex V. C. França, Gastroenterologist · Principal investigator
  • Newdata Clinical Research
    Aracaju, Sergipe 49075000, Brazil
    Recruiting
    • Katiane Soares Research Center Manager · Contactkatiane.soares@newdatatrials.com · 5511970306077
    • Alex V. C. França, Gastroenterologist · Principal investigator
  • Casa de Nossa Senhora Da Paz Ação Social Franciscana
    Bragança Paulista, São Paulo 12916900, Brazil
    Recruiting
    • Larissa Germana Silva · Contactlarissa.germana@unifag.com.br · 5511972076829
    • Rafaella S. D. Beltrame, Intensive care · Principal investigator
  • Synvia Campinas
    Campinas, São Paulo 1308756, Brazil
    Recruiting
    • Hilari R Bonito · Contacthilary.bonito@synvia.com · 5519993001616
    • Ana Lígia G. M. Germano, Endocrinologist · Principal investigator
  • Trialstar Campinas
    Campinas, São Paulo 13092108, Brazil
    Recruiting
  • Synvia Clinical Barra Funda
    São Paulo, São Paulo 01139000, Brazil
    Recruiting
    • Giovana M Berbel · Contactgiovana.berbel@synvia.com · 19994891366
    • Sara C Siqueira, Endocrinologist · Principal investigator
  • Iscp Sociedade Educacional
    São Paulo, São Paulo 03164000, Brazil
    Recruiting
08

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reached

Started Jun 2026 (actual). Primary completion is estimated for Jun 2027, 11 months after the start.

How these figures are worked out, and which studies are left out of them.

Registered
Jun 18, 2026
First posted
Jul 20, 2026
StartActual
Jun 18, 2026
Primary completionEst.
Jun 1, 2027
CompletionEst.
Jun 1, 2027
Last update
Jul 20, 2026
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Jul 20, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
09

Registry details

Key details

Study ID
NCT07712913
Responsible party
Sponsor
First posted
Jul 20, 2026
Start date
Jun 18, 2026
Primary completion
Jun 1, 2027 (estimated)
Completion
Jun 1, 2027 (estimated)
Last update
Jul 20, 2026

Study contacts

Juliana G. Augusto, Clinical Research Manager
Contact
juliana.augusto@brainfarma.ind.br
55-11-97677-6726
Juliana A. L. Antonio, Scientific Documentation Coord
Contact
juliana.antonio@brainfarma.ind.br
Mariana Ferreira, Sports Nutrition
principal investigator · A2Z CLINICAL - CENTRO DE PESQUISA CLÍNICA, Valinhos, São Paulo 13271130

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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