Dymista Allergen Chamber - Onset of Action Study

Inclusion Criteria

• Provide written informed consent.
• Male or female subjects (childbearing and non-childbearing potential, non-childbearing potential defined as females with no menstruation for at least 1 year at screening and documented Follicle-Stimulating Hormone (FSH) > 35 IU/L) aged 18 to 55 years (inclusive) at screening.
• History of SAR to ragweed pollen for at least the previous 2 ragweed pollen seasons.
• Positive skin prick test (SPT) response to ragweed pollen (allergen induced wheal diameter at least 3 mm larger than the negative control). A test performed at Cliantha Research in the previous 12 months may be used to qualify the subject.
• Willingness to complete all study visits.

To be eligible for Visit 2 EEU, a subject must additionally comply with the following criteria:

• Asymptomatic or with mild symptoms during the baseline recording of symptoms prior to start of the screening EEU (Visit 2):
• Total Nasal Symptom Score (TNSS) ≤ 3/12 with the score for each symptom being less than 2.

To be eligible for Visit 3, a subject must additionally comply with the following criteria during Visit 2 EEU:

• Demonstrate adequate symptomology:
• TNSS ≥ 6/12 on at least two Electronic Patient Data Acquisition Tablet (ePDAT TM) time point assessments during hours 0-2 in the EEU (Visit 2), with at least one occurring during the last two time points. Additionally, subjects will be required to meet a score of at least 2/3 for runny nose at least twice during hours 0-2 in the EEU, with at least one occurring during the last two time points.

To be eligible for randomization (Visit 3), a subject must additionally comply with the following criteria:

• Demonstrate adequate symptomology:
• TNSS ≥ 6/12 on at least two ePDATTM time point assessments during hours 0-2 in the EEU (Visit 3), with at least one occurring during the last two time points. Additionally, subjects will be required to meet a score of at least 2/3 for runny nose at least twice during hours 0-2 in the EEU, with at least one occurring during the last two time points.
• No evidence of complete nasal blockage on either one or both sides on anterior rhinoscopy within 30 minutes prior to dosing.

Exclusion Criteria

Safety concerns:

• History of allergic reaction to azelastine hydrochloride or fluticasone propionate or one of the excipients of the study treatments (e.g. benzalkonium chloride, phenylethyl alcohol, microcrystalline cellulose) or a component of the container.
• History of anaphylaxis, cardiovascular, pulmonary, hepatic, renal, gastrointestinal, haematological, endocrine, metabolic, psychiatric, neurological, or other disease at screening that may affect subject safety during the study or evaluation of the study endpoints at the discretion of the Investigator and/or designee.
• Subjects with a current diagnosis of asthma or subjects with measured Forced Expiratory Volume in 1 Second (FEV1) <75% of the predicted value using Global Lung Function Initiative set from 2012 for references.
• Pregnant, breast-feeding or planning a pregnancy during the study and women of childbearing potential not using adequate contraception. Women of childbearing potential not abstinent or using a highly effective method of birth control defined as those which result in a low failure rate (i.e. <1% per year) when used consistently and correctly such as implants, injectables, combined oral contraceptives, hormonal Intrauterine Devices (IUDs), barrier methods, or tubal ligation started at least 4 weeks prior to screening.

Lack of suitability for the study:

• Previous and concomitant treatments: use of prohibited therapies (Antihistaminic agents, all presentations; Theophylline, all presentations; Cromolyn sodium, all forms; Nedocromil sodium; Salbutamol, all presentations; Leukotriene modifiers, all presentations; Corticosteroids (inhaled, oral, intravenous); Topical corticosteroids (ocular, intranasal); Corticosteroids (intramuscular or intra-articular);