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Study on the Effectiveness and Safety of AP707, Amitriptyline, and Capsaicin for Patients with Chronic Pain from Diabetic Neuropathy

Fast replyRegistered drugNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying the effectiveness and safety of a treatment called AP707 for individuals experiencing chronic pain due to diabetic polyneuropathy. Diabetic polyneuropathy is a condition that affects the nerves, often leading to persistent pain. The trial aims to evaluate how well AP707 works as an additional treatment for managing this type of pain.

Participants in the study will receive either the AP707 treatment or a placebo, which looks like the treatment but does not contain the active ingredient. The study will be conducted over several weeks, with regular assessments to monitor changes in pain levels and overall well-being. The goal is to determine if AP707 can provide significant relief from pain compared to the placebo.

Throughout the trial, participants will be asked to report their pain levels and any changes in their condition. The study will also track any side effects or adverse events to ensure the safety of the treatment. By the end of the study, researchers hope to gather valuable information about the potential benefits of AP707 for those suffering from chronic pain due to diabetic polyneuropathy.

The research process

The trial runs in 8 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Beginning of the trial

    Upon joining the study, you will be asked to provide a signed and dated informed consent form. This confirms your understanding and agreement to participate in the trial.

    You will undergo an initial assessment to confirm eligibility, which includes verifying that you have experienced chronic pain due to diabetic polyneuropathy for at least three months and that your pain intensity is moderate to severe.

  2. Step 2

    Baseline assessment

    A baseline assessment will be conducted to establish your current pain levels and overall health status. This includes completing questionnaires such as the Numeric Rating Scale (NRS) for pain and the Neuropathic Pain Symptom Inventory (NPSI).

    You will also be asked to complete additional questionnaires to assess psychological distress, quality of life, and sleep quality.

  3. Step 3

    Treatment phase 1

    You will begin the first treatment phase, which lasts for 14 weeks. During this time, you will receive either the study medication AP707 or a placebo. The medication is administered as a sublingual spray, which means it is sprayed under the tongue.

    Your pain levels and other health indicators will be monitored regularly through scheduled visits and questionnaires.

  4. Step 4

    Evaluation at week 14

    At the end of week 14, your pain levels will be reassessed using the Numeric Rating Scale (NRS) and other questionnaires. This evaluation will help determine the effectiveness of the treatment during the first phase.

    You will continue to receive either the study medication or placebo as the trial progresses into the next phase.

  5. Step 5

    Treatment phase 2

    The second treatment phase extends from week 15 to week 26. You will continue with the same treatment regimen as in the first phase.

    Regular assessments will be conducted to monitor any changes in your pain levels and overall health.

  6. Step 6

    Evaluation at week 26

    At the end of week 26, another evaluation will be conducted to assess changes in your pain levels and other health indicators.

    This evaluation will help determine the effectiveness of the treatment during the second phase.

  7. Step 7

    Treatment phase 3

    The third and final treatment phase lasts from week 27 to week 52. You will continue with the same treatment regimen.

    Your health and pain levels will be monitored regularly through scheduled visits and questionnaires.

  8. Step 8

    Final evaluation at week 52

    At the end of week 52, a final evaluation will be conducted to assess the overall effectiveness of the treatment throughout the trial.

    This includes a comprehensive assessment of your pain levels, quality of life, psychological distress, and sleep quality.

Who can join the trial?

9 criteria

  • Signed and dated informed consent form.
  • Patients with chronic pain due to diabetic polyneuropathy for at least 3 months. Diabetic polyneuropathy is a type of nerve damage that can occur with diabetes, causing pain.
  • Female and male patients who are 18 years or older.
  • Patients with a life expectancy of more than 1 year.
  • Patients with optimized sCPT at the start of the study. sCPT refers to a specific treatment plan that is adjusted for the patient.
  • Willingness of both male and female patients to use reliable contraception during the study and for three months after taking the last study medication.
  • Good command of the German language to understand questionnaires in German.
  • Current moderate to severe pain with a pain intensity of 5 or more on the Numeric Rating Scale (NRS), which is a scale from 0 to 10 used to measure pain, indicating a need for further pain therapy.
  • Completed QUISS (Quantification Inventory for Somatoform Syndromes) questionnaire with a score of 45 or less. This questionnaire helps assess certain symptoms related to pain.

Who cannot join the trial?

3 criteria

  • Patients who do not have chronic pain due to diabetic polyneuropathy cannot participate. This means the study is only for those who have long-lasting pain caused by nerve damage from diabetes.
  • Patients who are not within the specified age range cannot participate. The study is for adults only.
  • Patients who are part of a vulnerable population cannot participate. This means people who might need special protection or care are not included.
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Investigated drugs

AP707 is a medication being tested to see how well it works and how well people can tolerate it when used as an additional treatment for chronic pain caused by diabetic polyneuropathy. Diabetic polyneuropathy is a condition where people with diabetes experience nerve damage, leading to pain, tingling, or numbness, usually in the feet and hands. AP707 is being studied to determine if it can help reduce this type of pain when added to the patient's current treatment plan.

What is already known about the treatment

AP707 – AP707 is administered orally in the form of tablets and is currently being studied for its effectiveness and safety in treating chronic pain caused by diabetic polyneuropathy. This medication is in the clinical trial phase, and its role in medicine is still being evaluated, with ongoing research to determine its benefits and potential side effects. The main therapeutic use of AP707 is to alleviate chronic pain associated with nerve damage due to diabetes. At the molecular level, AP707 works by modulating specific pathways in the nervous system to reduce pain signals. It is classified pharmacologically as an analgesic, which means it is designed to relieve pain.

Investigated diseases

Diabetic Polyneuropathy – Diabetic polyneuropathy is a type of nerve damage that occurs in individuals with diabetes. It primarily affects the peripheral nerves, which are responsible for sensation and movement in the limbs. The disease progresses gradually, often starting with numbness or tingling in the feet and hands. Over time, it can lead to more severe symptoms such as burning pain, muscle weakness, and loss of reflexes. As the condition advances, it may affect balance and coordination, making walking difficult. The progression of symptoms can vary widely among individuals, depending on factors like blood sugar control and duration of diabetes.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2022-500897-32-00Protocol codeDISCOVER_(PNP1)Estimated enrolment558 patientsSponsorApurano Pharmaceuticals GmbH

sourced from the EU Clinical Trials Register and site verification

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On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).