Mechanisms of Capsaicin Treatment in Idiopathic Rhinitis Patients and Controls

NCT ID: NCT01862523

Last Updated: 2014-12-05

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: PHASE4
• Total Enrollment: 39 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2012-02-29
• Study Completion Date: 2014-12-31

Brief Summary

Capsaicin nasal spray is used in daily practice against IR without knowledge about the exact mechanisms involved in this treatment. Therefore, this study aims to address this issue by studying the functional (electrophysiologic) changes after specific stimulations in IR patients and healthy controls before and after capsaicin/placebo treatment.

Detailed Description

As an essential step towards the improvement of the treatment of IR we will investigate the neural mechanisms underlying the therapeutic action of capsaicin. In particular, we plan to evaluate the effects of capsaicin on the functional properties of the innervation of nasal mucosa by monitoring the trigeminal nerve activity using measurements of negative mucosa potentials (NMP). NMPs, will be evoked by chemical and thermal stimuli in IR patients and healthy controls. Considering the evidence suggesting a role of sensory C-fibers in the pathophysiology of IR, we will employ low concentrations of irritants that specifically activate receptors expressed in those fibers, i.e., capsaicin for TRPV1 and cinnamaldehyde and allyl-isothiocyanate (mustard oil) for TRPA1. The same stimulations will be performed immediately after capsaicin treatment, and after 4 weeks, 3 months and 6 months. This will allow for an objective assessment of the functionality of the C-fiber innervation before the treatment, during the phase of therapeutic response and during the period of recurrence of the IR symptoms. The results of the NMP measurements will be contrasted with the therapeutic response and with evaluations of nasal congestion, nasal sensitivity and the presence of neuro-mediators found in nasal biopsies. Importantly, the independent assessment of the NMP responses mediated by either TRPV1 or TRPA1 will allow determining the specific role of these nociceptors in the pathophysiology of IR, which, in turn, may help to design more specific and effective therapies.

Conditions

Rhinitis

Study Design

• Allocation Method: NON_RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: TRIPLE

Study Groups

diluent

diluent

Group Type: PLACEBO_COMPARATOR

diluent

Intervention Type: BIOLOGICAL

diluent

capsaicin

capsaicin

Group Type: EXPERIMENTAL

Capsaicin

Intervention Type: BIOLOGICAL

Thirty-three\* well-characterized IR patients will be recruited and screened for participation in this study with nasal capsaicin spray (0,1 mmol/l ) using the treatment regimen described by van Rijswijk et al. (1 x 5 applications in one day, with 1 hour between each application)

control healthy volunteers

control healthy volunteers

Group Type: NO_INTERVENTION

No interventions assigned to this group

Interventions

Capsaicin

Thirty-three\* well-characterized IR patients will be recruited and screened for participation in this study with nasal capsaicin spray (0,1 mmol/l ) using the treatment regimen described by van Rijswijk et al. (1 x 5 applications in one day, with 1 hour between each application)

Intervention Type: BIOLOGICAL

diluent

diluent

Intervention Type: BIOLOGICAL

Eligibility Criteria

Inclusion Criteria

1. Patients with persistent (> 52w) rhinological symptoms: nasal discharge, sneezing, congestion for an average of at least 1 h per day for at least 5 days during a period of 14 days, negative skin prick test or negative RAST, and without structural abnormalities explaining nasal obstruction will be proposed to participate in the trial.

2. Age > 18 and < 60 years

3. Written informed consent

4. Willingness to adhere to visit schedules

5. Adequate contraceptive precautions in female patients with childbearing potential

6. Unresponsiveness to nasal steroid spray (4 weeks of use)

Exclusion Criteria

1. Age < 18 and > 60 years

2. Patients with AR, demonstrated by either positive skin prick test or RAST

3. Asthma

4. Structural abnormalities: nasal polyps, severe septal deviation (septum reaching concha inferior or lateral nasal wall.

5. Systemic steroid treatment less than 4 weeks before the inclusion in the study.

6. Nasal steroid spray less than 4 weeks before the inclusion, oral leukotriene antagonists or long-acting antihistamines less than 2 weeks before the inclusion.

7. Inability of the patient to stop taking medication affecting nasal function.

8. Evidence of infectious rhinitis/rhinosinusitis.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 60 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Universitaire Ziekenhuizen KU Leuven

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Laura Van Gerven, Doctor

Role: PRINCIPAL_INVESTIGATOR

UZ Leuven

Peter Hellings, Doctor

Role: PRINCIPAL_INVESTIGATOR

UZ Leuven

Locations

UZ Leuven

Leuven, Vlaams-Brabant, Belgium

Countries

Belgium

Other Identifiers

mucosal potentials in the nose

Identifier Type: -

Identifier Source: org_study_id