Clinical evidence

Please find below an overview of our extensive clinical documentation showing effective alleviation of symptoms.

Please contact us to download a pdf of our Scientific summary of completed clinical studies and the technology Temperatude controlled Laminar Airflow (TLA; Airsonett®).

Temperature-controlled Laminar Airflow (TLA) in symptomatic severe asthma – a post hoc analysis of severe exacerbations, quality of life and health economics

A. J. Chauhan, G. Eriksson, W. Storrar, T. Brown, S. Peterson, F. Radner, L. G. D’Cruz, P. Miller & L. Bjermer: BMC Pulmonary Medicine volume 22, Article number: 407 (2022)

This post hoc analysis demonstrated an effect of TLA over placebo on severe exacerbations, asthma control and health economics in a subgroup of patients with more symptomatic severe allergic asthma. The results are consistent with the present recommendations for TLA.

For patients with poor control defined by ACQ7 > 3, the difference in EQ5D-5 L utility scores between TLA and placebo was significant at 9 and 12 months with a cost-effective ICER.

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Temperature-controlled laminar airflow in adult atopic dermatitis patients – an observational study.

S Traidl, L M Roesner, P Kienlin, G Begemann, A Schreiber, T Werfel, A Heratizadeh: PMID: 34242453 DOI: 10.1111/jdv.17507

The three-month observational study, with an extension phase of an additional 9 months, investigated the effect of an add-on treatment with TLA in 10 HDM-IgE-sensitized patients with moderate-to-severe AD and a history of clinically relevant house dust mite allergy. The study showed significant improvement in a majority of the patients, measured as SCORAD, EASI, PGA, DLQI. In vitro analysis was also performed after 3 and 12 months, underpinning the clinical results.

Excerpt from the conclusion in the publication:
“Together, the findings of this proof-of-concept study indicate improvement of disease severity in HDM-sensitized adult AD patients during the add-on treatment with a TLA device. In conclusion, this study is the first to suggest beneficial effects of TLA in HDM-sensitized adult AD patients regarding objective, subjective and in vitro parameters.”

Effect of nocturnal Temperature-controlled Laminar Airflow on the reduction of severe exacerbations in patients with severe allergic asthma: a meta-analysis

A.J. Chauhan, T. P. Brown, W. Storrar, L. Bjermer, G. Eriksson, F. Radner, S. Peterson & J. O. Warner: European Clinical Respiratory Journal, Vol 8 2021

This meta-analysis of individual patient data shows a beneficial effect on severe exacerbations and quality of life for TLA over placebo in more symptomatic patients with severe allergic asthma. These outcomes support the national management recommendations for patients with symptomatic severe allergic asthma. The actual effect of TLA on severe exacerbations should be confirmed in a prospective study with larger numbers of patients.
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Time to onset of improvements in Quality of Life from Temperature controlled Laminar Airflow (TLA) in severe allergic asthma.

L. Bjermer, G. Eriksson, F. Radner, Stefan Peterson, J.O. Warner, Respiratory Medicine 147 (2019), 19-25,

​A re-analysis of time to onset (TTO) from a previously published study by Boyle et al, using the Airsonett Air4 Temperature-controlled Laminar Airflow technology (TLA), by Professor Leif Bjermer, concludes that Nocturnal treatment with TLA provided a statistically significant and clinically relevant improvement in Quality of Life (AQLQ) within 3 months in patients with poorly controlled asthma.

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4Temperature-controlled laminar airflow (TLA) device in the treatment of children with severe atopic eczema: Open-label, proof-of-concept study. Gore C et al. Clin Exp Allergy 2018. Pre-published manuscript doi: 10.1111/cea.13105

The study was designed to evaluate the effectiveness of overnight treatment with the TLA device (Airsonett AIR4) in children and adolescents with severe allergic eczema over a 12-month period.

Fifteen children (2-16 years) with longstanding severe allergic eczema (atopic dermatitis) were followed during a 12-month treatment period. The study results included significant improvements in SCORring of Atopic Dermatitis (SCORAD) index, Investigator Global Assessment (IGA) and Family Dermatology Quality of Life index (FDQLI) after 12 months treatment. Importantly, the clinical improvement was accompanied by a reduction in the use of potent topical corticosteroids.

Comparison between temperature-controlled laminar airflow device and a room air-cleaner in reducing exposure to particles while asleep Spilak MP, Sigsgaard T, Takai H, et al PLoS ONE 2016;11(11): e0166882

This study used full-scale laboratory measurements with a thermal manikin positioned on an experimental bed. Three ventilation settings were tested: with no filtration system operated, use of portable air cleaner and use of a temperature-controlled laminar airflow (TLA) device.

The first part of the experiment investigated the air-flow characteristics in the breathing zone. In the second part, particle removal efficiency was estimated.

Measured in the breathing zone, the room air cleaner demonstrated high turbulence intensity, high velocity and turbulence diffusivity level, with a particle reduction rate of 52% compared to baseline after 30 minutes. The TLA device delivered a laminar airflow to the breathing zone with a reduction rate of 99.5%. During a periodical duvet lifting mimicking a subject’s movement in bed, the particle concentration was significantly lower with the TLA device compared to the room air cleaner.

The TLA device provided a barrier which significantly reduced the introduction of airborne particles into the breathing zone. Further studies should be conducted for the understanding of the transport of resuspended particles between the duvet and the laying body.

Use of temperature-controlled laminar airflow in the management of atopic asthma: clinical evidence and experience Warner JO.Ther Adv Respir Dis 2017;11:181-188

Avoidance of allergens in the treatment of asthma has hitherto not achieved significant benefit despite the strong evidence that allergy both increases severity and contributes to exacerbations of asthma. House dust mite, cat and dog allergens are the most common perennial allergic triggers and most avoidance strategies have focused on reducing exposures in bedrooms.

Cochrane reviews have suggested that they neither significantly reduce allergen levels nor improve asthma. While the lack of efficacy may be assumed to be a consequence of exposures occurring outside the bedroom, prolonged sleep is associated with increased susceptibility to bronchospasm and airway inflammation. Thus, if efficient reductions in allergen exposure could be achieved during sleep, it might be expected that this would result in significant improvements in control of asthma.

The temperature-controlled laminar airflow (TLA) is a system which can be employed over beds in a domestic environment and results in massive reductions in particulate exposure of recumbent subjects, including highly respirable allergens such as Fel. D1 from cats. Trials of TLA have demonstrated highly significant improvements in asthma quality of life and reductions on airway inflammation as monitored by exhaled nitric oxide levels.

Furthermore, in patients with the worst disease, severe exacerbation frequency was significantly reduced. Based on UK health-service costs, the use of TLA falls well below the National Institute for Health and Care Excellence (NICE) threshold for the incremental cost effectiveness ratio (ICER) per quality adjusted life year (QALY). Indeed, for those with frequent exacerbations, it is cost saving and should be prescribed for such allergic asthmatic patients.

Economic analysis of temperature-controlled laminar airflow (TLA) for the treatment of patients with severe persistent allergic asthma. Brazier P, Schauer U, Hamelmann E, Holmes S, Pritchard C and Warner JO. Open Resp Res 2016;3:e000117

The objective of this study was to quantify the cost-effectiveness of TLA (Airsonett AB) technology as an add-on to standard asthma management drug therapy in the UK.

The main performance measure of interest is the incremental cost per quality-adjusted life year (QALY) for patients using TLA in addition to usual care versus usual care alone. The incremental cost of TLA use is based on an observational clinical study monitoring the incidence of exacerbations with treatment valued using NHS cost data.

The clinical effectiveness, used to derive the incremental QALY data, is based on a randomised double-blind placebo-controlled clinical trial comprising participants with an equivalent asthma condition. For a clinical cohort of asthma patients as a whole, the incremental cost-effectiveness ratio (ICER) is £8998 per QALY gained, that is, within the £20 000/QALY cost-effectiveness benchmark used by the National Institute for Health and Care Excellence (NICE).

Sensitivity analysis indicates that ICER values range from £18 883/QALY for the least severe patients through to TLA being dominant, that is, cost saving as well as improving quality of life, for individuals with the most severe and poorly controlled asthma.

1Improved asthma control in patients with severe persistent allergic asthma after 12 months of nightly temperature-controlled laminar airflow (TLA): An observational study with retrospective comparisons. Schauer U, Bergmann K-C, Gerstlauer M et al. Eur Clin Respir J 2015, 2: 28531

The objective of this obsersvational study was to evaluate the effects of nighttime TLA when used during real-life conditions for 12 consecutive months in addition to the patients’ regular medication.

It included patients with inadequately controlled moderate-to-severe allergic asthma who received add-on treatment with TLA for 12 consecutive months. Data on medication use, asthma control, asthma symptoms, lung function, use of hospital resources, and exacerbations were collected after 4 and 12 months and compared with corresponding data collected retrospectively from medical records during the year prior to inclusion in the study. The study used data from 30 patients (mean age 28; range 8–70) completing 4 months and 27 patients completing 12 months of TLA use are presented. The mean number of exacerbations was reduced from 3.6 to 1.3 (p<0.0001), and the ratio of asthma-related emergency room visits or hospitalizations diminished from 72.4 to 23.3% (p=0.001) or from 44.8 to 20.0% (p<0.05), respectively, after 12 months of TLA use.

The Asthma Control Test index increased from 14.1 to 18.5 (p<0.0001). After 4 months of TLA use, clear improvements can be shown for most variables in line with the data collected after 12 months. Conclusion presents that the addition of TLA to the patients’ regular medication significantly reduced exacerbations, asthma symptoms, and the utilization of hospital resources.

The data support that TLA may be an important new non-pharmacological approach in the management of poorly controlled allergic asthma.

Effect of a novel temperature-controlled laminar airflow device on personal breathing zone aeroallergen exposure. Gore RB, Boyle RJ, Gore C, et al. Indoor Air 2015;25:3644

The aim of this study is to evaluate its effects on personal cat allergen and particulate exposures in a simulated bedroom environment.

Five healthy volunteers lay under an active and an inactive temperature‐controlled laminar airflow device for 175 min, in a simulated bedroom containing bedding from a cat owner. Total airborne particles (≥0.5 – ≥10 μm diameter) were quantified with a laser particle counter. Airborne allergen was sampled with Institute of Occupational Medicine filters. Inhaled exposure was sampled with nasal air samplers. Allergen‐containing particles were quantified by immunoassay.

Treatment reduced total airborne particles (>0.5 μm diameter) by >99% (P < 0.001) and reduced airborne allergen concentration within the breathing zone (ratio of median counts = 30, P = 0.043). Treatment reduced inhaled allergen (ratio of median counts = 7, P = 0.043). Treatment was not associated with a change in airborne allergen concentration outside of the breathing zone (P = 0.160).

Temperature‐controlled laminar airflow treatment of individuals in an allergen‐rich experimental environment results in significant reductions in breathing zone allergenic and non‐allergenic particle exposure, and in inhaled cat allergen exposure. These findings may explain the clinical benefits of temperature‐controlled laminar airflow.

Analysis of changes in airborne pollutant levels in response to nocturnal temperature controlled laminar airflow.Bakshi D et al. Treatment, Allergy 2014 69 (Suppl. 99), 454–572

Black carbon (BC) and other particulate matter (PM) especially those <0.1 lm in size (nanoparticles), are the main drivers of pollution-related cardiorespiratory illness. Recent studies have shown that nocturnal temperature controlled laminar airflow (TLA) reduces inhalant PM exposure in a simulated environment.

2Nocturnal temperature controlled laminar airflow for treating atopic asthma: a randomised controlled trial. Boyle RJ, Pedroletti C, Wickman M, et al. 
Thorax 2012;67:215-221

This randomised, double-blind, placebo-controlled, parallel-group trial was designed to determine whether environmental control using nocturnal temperature controlled laminar airflow (TLA) treatment could improve the quality of life of patients with persistent atopic asthma.

Set in nineteen European asthma clinics with participants 312 patients aged 7–70 with inadequately controlled persistent atopic asthma.

The main outcome measure Proportion of patients with an increase of ≥0.5 points in asthma quality of life score after 1 year of treatment.

Results showed TLA devices were successfully installed in the bedrooms of 282 (90%) patients included in the primary efficacy analysis. There was a difference in treatment response rate between active (143 of 189, 76%) and placebo (56 of 92, 61%) groups, difference 14.8% (95% CI 3.1 to 26.5, p=0.02).3 In patients aged ≥12, on whom the study was powered, the difference in response rate was similar-active 106 of 143 (74%), placebo 42 of 70 (60%), difference 14.1% (0.6 to 27.7, p=0.059). There was a difference between groups in fractional exhaled nitric oxide change of −7.1 ppb (−13.6 to −0.7, p=0.03). Active treatment was associated with less increase in cat-specific IgE than placebo. There was no difference in adverse event rates between treatment groups.

In conclusion, inhalant exposure reduction with TLA improves quality of life, airway inflammation and systemic allergy in patients with persistent atopic asthma. TLA may be a treatment option for patients with inadequately controlled persistent atopic asthma.

3Clinical effects of purified air administered to the breathing zone in allergic asthma: A double-blind randomized cross-over trial. Pedroletti C, Millinger E, Dahlén B, et al. Respir Med 2009;103:1313-9

This clinicial trial examined a novel treatment using temperature regulated laminar airflow with a very low particle concentration directed to the breathing zone of teenagers and young adults with mild to moderate allergic asthma during night sleep.We hypothesised that the decreased allergen exposure during the night would have an effect on bronchial inflammation and quality of life.Twenty-two patients (mean 18.8 years) were randomized to start with active or placebo treatment for 10 weeks. All patients received both active and placebo treatment with unfiltered air, with a 2-week wash-out period in between treatments.

Maintenance treatment with inhaled corticosteroids was unaltered during the trial period. Health related quality of life (miniAQLQ) was the primary effectiveness measure. Exhaled nitric oxide (FeNO) and spirometry were also investigated.

Active treatment resulted in an improved miniAQLQ compared to placebo (mean score 0.54, p < 0.05, n = 20). An effect on bronchial inflammation was also detected with significantly lower FeNO values during the active treatment period (mean −6.95 ppb, p < 0.05, n = 22). Both effects were evident after 5 weeks. The change in lung function was not statistically significant.

In conclusion, clean air, administered directly to the breathing zone during sleep, can have a positive effect on bronchial inflammation and quality of life in patients with perennial allergic asthma.