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Study on Botulinum Toxin Type A for Patients with Treatment-Resistant Chronic Migraine

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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 effects of a treatment for chronic migraine, a condition characterized by frequent and severe headaches. The treatment being tested involves the use of Botulinum toxin type A, commonly known as Botox, which is injected to target a specific area called the sphenopalatine ganglion. This area is associated with headache pain, and the treatment aims to help those who have not found relief from other medications. The study will also use a special device called MultiGuide® to assist in accurately delivering the treatment.

The purpose of the study is to determine how effective this treatment is for people with chronic migraine who have not responded well to other treatments. Participants in the study will receive either the Botox treatment or a placebo. The study will monitor changes in the number of headache days and the intensity of headaches over a period of time. Participants will be observed for any side effects or adverse events that may occur during the study.

The study will take place over several weeks, with regular check-ins to assess the impact of the treatment. Participants will be asked to maintain their current headache medication routines throughout the study. The goal is to see if the Botox treatment can reduce the frequency and severity of headaches and improve the quality of life for those suffering from chronic migraine.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Joining the study

    Upon joining the study, the patient must provide informed and written consent. This is a formal agreement to participate after understanding the study's procedures and potential risks.

    The patient must be between 18 and 70 years old and have a history of chronic migraine for at least one year. The patient must also have tried at least three different medications from two different classes without success.

  2. Step 2

    Baseline assessment

    Before starting the treatment, a baseline assessment is conducted. This involves documenting the current frequency and intensity of headaches and migraines.

    The patient must not change their current preventive headache medication regimen during the study.

  3. Step 3

    Treatment administration

    The treatment involves an injection of botulinum toxin type A towards the sphenopalatine ganglion (SPG). This is done using an image-guided surgical device called MultiGuide®.

    The injection is administered as a solution for injection.

  4. Step 4

    Post-treatment monitoring

    After the treatment, the patient is monitored for changes in headache frequency and intensity. This monitoring occurs over several weeks.

    The primary focus is on the difference in the mean monthly headache days between weeks 5 to 8 after the intervention.

  5. Step 5

    Evaluation of outcomes

    The study evaluates the effectiveness of the treatment by comparing the patient's headache and migraine data before and after the treatment.

    Secondary outcomes include the occurrence of any adverse events, changes in migraine days, headache intensity, and quality of life.

Who can join the trial?

17 criteria

  • Provide informed and written consent to participate in the study.
  • If you are a woman who can have children, you must agree to use very effective birth control for 4 weeks after the injection.
  • Be able to understand the study procedures and follow them for the entire study duration.
  • Be a male or female between 18 and 70 years old.
  • Be able to understand a Scandinavian language well enough to fully understand the study information, both written and spoken.
  • Have migraines, with or without aura, that meet the criteria for **chronic migraine** according to the International Classification of Headache Disorders (ICHD) at the time of joining the study.
  • Have had chronic migraines for at least 1 year before joining the study.
  • Have started having episodic migraines before the age of 50 and chronic migraines before the age of 65.
  • Your condition is **pharmacologically refractory**, meaning that at least 3 medications from at least 2 different classes have not worked well, are not suitable for you, or have caused intolerable side effects. These classes include:
    • Beta-blockers
    • RA(A)S-inhibitors
    • Calcium-antagonists
    • Antiepileptic drugs
    • Tricyclic antidepressants
    • Botulinum toxin A
    • CGRP antagonists
    • Have not changed the type, dosage, or frequency of your preventive headache medications for less than 3 months before the start of the study, or for a minimum of 5 half-lives of the medication, whichever is longer.
    • Agree to keep your current preventive headache medication regimen the same (no changes in type, frequency, or dose) throughout the entire study period.

Who cannot join the trial?

8 criteria

  • Patients who are not experiencing chronic migraine. Chronic migraine is a type of headache that occurs on 15 or more days each month, with migraine features on at least 8 of those days.
  • Patients who are not within the specified age range for the study. The study is open to certain age groups only.
  • Patients who are not part of the specified clinical trial groups. The study is designed for specific groups of people.
  • Patients who are not willing or able to follow the study procedures and requirements.
  • Patients who have other medical conditions or are taking medications that might interfere with the study treatment.
  • Patients who are pregnant or breastfeeding, as the study treatment may not be safe for them.
  • Patients who have a history of allergic reactions to the study treatment or similar treatments.
  • Patients who have participated in another clinical trial recently, as this might affect the results of the study.
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Investigated drugs

Botulinum Toxin Type A is used in this trial to block the sphenopalatine ganglion, which is a group of nerves linked to headaches. This treatment is being tested for people who have chronic migraines that do not respond to other treatments. The goal is to see if this approach can reduce the frequency or severity of migraines. The procedure involves using a special device to guide the application of the botulinum toxin to the targeted area.

What is already known about the treatment

Botulinum Toxin Type A – This medication is administered through an injection, specifically targeting the sphenopalatine ganglion using an image-guided surgical device. It is currently being studied in clinical trials for its effectiveness in treating chronic migraines that do not respond to other treatments. The main therapeutic indication is for chronic migraine relief. At the molecular level, botulinum toxin type A works by blocking the release of certain neurotransmitters, which helps reduce muscle contractions and pain signals. It is classified pharmacologically as a neurotoxin.

Investigated diseases

Chronic Migraine – Chronic migraine is a neurological condition characterized by experiencing headaches on 15 or more days per month, with at least 8 of those days involving migraine features. These headaches can be accompanied by symptoms such as nausea, vomiting, and sensitivity to light or sound. The condition often progresses from episodic migraines, where headaches occur less frequently, to a more persistent state. Over time, the frequency and severity of the headaches can increase, significantly impacting daily life and activities. The exact cause of chronic migraine is not fully understood, but it is believed to involve a combination of genetic, environmental, and neurological factors. Managing triggers and lifestyle changes can sometimes help in reducing the frequency of migraine attacks.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-515165-34-00Estimated enrolment170 patientsSponsorSt. Olavs Hospital HF

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