Clinical trial NCT01839591: Bronchial Thermoplasty: Effect on Neuronal and Chemosensitive Component of the Bronchial Mucosa
Official title: Treatment of Bronchial Severe Asthma With Bronchial Thermoplasty. Assessment of Efficacy and Safety of Treatment, Study of Effects on Neuronal and Chemosensitive Component of the Bronchial Mucosa Pre and Post Treatment
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Severe Persistent Asthma
Lead sponsor: Azienda USL Reggio Emilia - IRCCS
Sponsor class: OTHER_GOV
First posted: 2013-04-25
Enrollment: 12
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: BASIC_SCIENCE

Brief summary: In severe bronchial asthma the mechanism of inflammation and bronchospasm is complex and still not clarified. The smooth muscle cells play an important role from the mechanical point of view, as a culmination of neurogenic stimuli and inflammatory cytokines that determine as final effect the bronchospasm and over time a hypertrophy of the muscular coat. There are some other hypothesis that the smooth muscle cells may play a role as central regulator of chemical mediators that cause bronchospasm and inflammation, although there are currently no firm conclusions 2 According to other studies3,the nerve receptors TRANSIENT RECEPTOR POTENTIAL VANILLOID TYPE 1 have a great importance in the complex mechanism of airway inflammation too. (There are at least 4)

These receptors would intervene according to the following mechanism:

1. Irritants on the bronchial mucosa stimulate the TRANSIENT RECEPTOR POTENTIAL VANILLOID TYPE 1 present on afferent endings of sensory fibers, unmyelinated C (chemiosensitive neurons)
2. On the same afferent axon acting factors with the activation effect (lowering the activation threshold, increase the expression, promote the translocation of TRPV1 receptor on the membrane). Among these factors the neurotrophins of which the most important NERVE GROWTH FACTOR (NGF)
3. The activation of TRPV1 (through release of Ca2 + +) determines two efferent responses:

   1. CENTRALLY-MEDIATED
   2. LOCAL AXON Reflex

Investigators hypothesized that BT may have a strong influence on the destruction of nerve receptors TRPV1 and unmyelinated nerve fibers located in the mucosa going to stop reflections both central and local authorities responsible for the activation of bronchospasm. In support of this hypothesis, there are some anatomical studies4, which show that these receptors are more numerous at the level of main bronchi which are the main target of BT. Please note in this context that it is already known that in thermoablations commonly used in cardiology it is used a radio frequency with development of heat controlled to 65 °, as in the BT, able to interrupt the circuit nervous responsible for the activation of the circuit causing the abnormal 'arrhythmia.

Detailed description: The mechanism of action the bronchial thermoplasty exerts the positive action demonstrated by the studies through is not yet well understood yet. The only action on the denaturation and destruction of the smooth muscle layer of the bronchi at intermediate and high caliber perhaps not fully explain its action, taking into account that most of the smooth muscle loading of the small airways is minimally altered by the procedure. From the premises outlined in the section on the mechanism of inflammation we hypothesized that BT may have a strong influence on the destruction of nerve receptors TRPV1 and unmyelinated nerve fibers located in the mucosa going to stop reflections both central and local authorities responsible for the activation of bronchospasm. In support of this hypothesis, there are some anatomical studies4, which show that these receptors are more numerous at the level of main bronchi which are the main target of BT. Please note in this context that it is already known that in thermoablations commonly used in cardiology it is used a radio frequency with development of heat controlled to 65 °, as in the BT, able to interrupt the circuit nervous responsible for the activation of the circuit causing the abnormal 'arrhythmia.

Eligibility criteria: Inclusion Criteria:

1. Patient with severe persistent asthma uncontrolled found in stable for at least 3 weeks
2. Patient receiving regular treatment with inhaled corticosteroids (beclomethason\> 1000 mcg or equivalent) and LABA (salmeterol\> = 100 mcg or equivalent)
3. AQLQ score \<6.25
4. FEV1\> = 60% predicted
5. Patients not smoking for at least one year

Exclusion Criteria:

1. acute asthma with life threatening
2. concomitant respiratory diseases (eg, COPD or emphysema)
3. use of ß-blocker drugs
4. severe active infection in the last 2 weeks
5. Pacemaker, internal defibrillator or other implanted electronic device.
6. Known sensitivity to medications used to perform bronchoscopy, including lidocaine, atropine and benzodiazepines.
7. Currently known bleeding disorder is not well controlled.
8. Inability to stop prior to the procedure taking anticoagulants, antiplatelet agents, aspirin or non-steroidal anti-inflammatory drugs
9. 18 years
10. Pregnant women

Primary outcomes:
measure: analysis of the risk and benefit profile with questionnaire ACT and AQLQ
timeFrame: Change from Baseline in ACT and AQLQ Questionaire one year after the end of the procedure
Secondary outcomes:
measure: Analyze the changes in the state of innervation and nerve receptors before and after BT on histological samples of the bronchial mucosa
timeFrame: biopsies every 4 weeks( during the treatment)
Other outcomes:
measure: Evaluate the effect of BT on the run neurogenic inflammation by analysis of the chemical mediators of inflammation on histological samples of the bronchial mucosa.
timeFrame: biopsies every 4 weeks (during the treatment)
Locations:
city: Reggio Emilia
country: Italy
facility: REGGIO EMILIA IRCCS, Santa Maria Nuova Hospital
Study officials:
name: Nicola NF Facciolongo, M.D.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Facciolongo N, Di Stefano A, Pietrini V, Galeone C, Bellanova F, Menzella F, Scichilone N, Piro R, Bajocchi GL, Balbi B, Agostini L, Salsi PP, Formisano D, Lusuardi M. Nerve ablation after bronchial thermoplasty and sustained improvement in severe asthma. BMC Pulm Med. 2018 Feb 8;18(1):29. doi: 10.1186/s12890-017-0554-8.