Standardising Nasal Allergen Challenge in Adult With Hay Fever
Palabras clave
Abstracto
Descripción
Nasal allergen challenge (NAC) is a useful tool in the investigation of allergic rhinitis, including grass pollen-induced seasonal allergic rhinitis (hay fever). We have experience in using NAC to investigate the clinical and immunological effects of allergen exposure and in using NAC as a surrogate outcome to assess the efficacy of treatments for allergic rhinitis. The procedure is safe and well tolerated. In order for NAC to be a valid tool, it is essential that the allergen extracts used are standardised in terms of concentration and stability in solution. We have previously used an extract of Timothy Grass (Phleum pratense) pollen, Aquagen (ALK-Abello, Denmark). Aquagen is supplied as a dry powder, to be reconstituted prior to use by dissolving in an albumin-based diluent. Unfortunately, Aquagen production has been discontinued, but the identical allergen is now available as Timothy Grass lyophilisate tablet, Grazax (ALK-Abello), an approved and licensed product for treatment of severe seasonal allergic rhinitis. Grazax consists of purified, freeze-dried Timothy Grass pollen extract, plus only three excipients, gelatin (from fish), mannitol and sodium hydroxide. Preliminary investigations have shown that Grazax tablets can be dissolved in saline to produce identical concentrations of allergen to Aquagen, with the same stability profile in vitro. We anticipate therefore, that the clinical effect when used for nasal allergen challenges would be equivalent to the use of Aquagen for a given allergen concentration. In this study we intend to confirm that nasal symptoms produced during the NAC with either Aquagen or Grazax will be equivalent. We will recruit volunteers with grass pollen-induced hay fever to undergo NAC with each allergen source, sequentially. In an open, randomised-order, cross-over study. The primary outcome will be patient-reported nasal symptoms (according to a standardised scoring system) in the 60 minutes after each nasal challenge.
fechas
| Verificado por última vez: | 08/31/2019 |
| Primero enviado: | 08/27/2019 |
| Inscripción estimada enviada: | 09/01/2019 |
| Publicado por primera vez: | 09/03/2019 |
| Última actualización enviada: | 09/11/2019 |
| Última actualización publicada: | 09/15/2019 |
| Fecha de inicio real del estudio: | 09/16/2019 |
| Fecha estimada de finalización primaria: | 10/29/2019 |
| Fecha estimada de finalización del estudio: | 11/28/2019 |
Condición o enfermedad
Intervención / tratamiento
Diagnostic Test: Aquagen (Starts with Aquagen and finish with Grazax)
Diagnostic Test: Grazax (Starts with Grazax and finish with Aquagen)
Fase
Grupos de brazos
| Brazo | Intervención / tratamiento |
|---|---|
| Experimental: Aquagen (Starts with Aquagen and finish with Grazax) In order to explore a possible order effect with the challenges, in this single group cross-over trial, participants will be randomised (by computer-generated randomisation) to receive either Aquagen or Grazax as the first challenge, followed by the other allergen extract at the second challenge a minimum of 4 weeks later. | Diagnostic Test: Aquagen (Starts with Aquagen and finish with Grazax) To compare the clinical allergic response after direct installation of an aqueous solution of Aquagen Timothy Grass pollen extract via nasal allergen challenge with the clinical allergic response after direct installation of an aqueous solution of Grazax Timothy Grass lyophilisate tablets via nasal allergen challenge in grass pollen allergic individuals. |
| Experimental: Grazax (Starts with Grazax and finish with Aquagen) In order to explore a possible order effect with the challenges, in this single group cross-over trial, participants will be randomised (by computer-generated randomisation) to receive either Aquagen or Grazax as the first challenge, followed by the other allergen extract at the second challenge a minimum of 4 weeks later. | Diagnostic Test: Grazax (Starts with Grazax and finish with Aquagen) To compare the clinical allergic response after direct installation of an aqueous solution of Aquagen Timothy Grass pollen extract via nasal allergen challenge with the clinical allergic response after direct installation of an aqueous solution of Grazax Timothy Grass lyophilisate tablets via nasal allergen challenge in grass pollen allergic individuals. |
Criterio de elegibilidad
| Edades elegibles para estudiar | 18 Years A 18 Years |
| Sexos elegibles para estudiar | All |
| Acepta voluntarios saludables | si |
| Criterios | Inclusion Criteria: 1. Adults age 18 to 65 years. 2. A clinical history of moderate-severe grass pollen-induced allergic rhino conjunctivitis for at least 2 years with peak symptoms from mid-May to mid-July. 3. Positive skin prick test response, defined as wheal diameter ≥ 5 mm, to timothy grass pollen. 4. For women of childbearing age, a negative urine pregnancy test at the time of screening and willingness to use an effective form of contraception for the duration of involvement in the study. 5. The ability to give informed consent and comply with study procedures. Exclusion Criteria: 1. History of previous grass pollen allergen immunotherapy at any time in the past. 2. Pre-bronchodilator FEV1 < 70% of predicted value at screening. 3. A clinical history of symptomatic allergic rhinitis and/or asthma caused by an allergen other than grass pollen to which the participant is regularly exposed either seasonally (eg. tree pollen, weed pollen and moulds) or perennially (house dust mite, cat, dog dander). 4. Perennial asthma requiring regular inhaled corticosteroids. 5. History of emergency visit or hospital admission for asthma in the previous 12 months. 6. History of chronic obstructive pulmonary disease 7. History of significant recurrent acute sinusitis, defined as 2 episodes per year for the last 2 years, all of which required antibiotic treatment. 8. History of chronic sinusitis, defined as sinus symptoms lasting greater than 12 weeks that includes 2 or more major factors or 1 major factor and 2 minor factors. Major factors are defined as facial pain or pressure, nasal obstruction or blockage, nasal discharge or purulence or discolored postnasal discharge, purulence in nasal cavity, or impaired or loss of smell. Minor factors are defined as headache, fever, halitosis, fatigue, dental pain, cough, ear pain, pressure, or fullness. 9. At screening visit, current symptoms of, or treatment for, upper respiratory tract infection, acute sinusitis, acute otitis media, or other relevant infectious process; serous otitis media is not an exclusion criterion. Participants may be re-evaluated for eligibility after symptoms resolve. 10. History of life-threatening anaphylaxis or angioedema. 11. Ongoing systemic immunosuppressive treatment. 12. The use of any investigational drug within 30 days of the screening visit. 13. The presence of any medical condition that the investigator deems incompatible with participation in the study. 14. History of fish allergy with positive skin test and/or positive specific IgE test to vertebrate/finned fish (due to potential fish allergen exposure from fish-gelatin in Grazax). |
Salir
Medidas de resultado primarias
1. Total nasal symptoms scores after nasal allergen challenge [60 minutes]
Medidas de resultado secundarias
1. Peak nasal inspiratory flow [Baseline, 60 minutes]
2. Incidence of Adverse Events [48 hours]
