A Study Evaluating the Safety and Effectiveness of a Nasal Spray to Treat Seasonal Allergies

Inclusion Criteria: * Male and female subjects 12 years of age and older * Provide written informed consent/pediatric assent. If the subject is a minor, parent or legal guardian must give written informed consent * Subjects must have moderate-to-severe rhinitis, defined as having one or more of the following: 1. Sleep disturbance 2. Impairment of daily activities, leisure and/or sport 3. Impairment of school or work 4. Troublesome symptoms * Screening Visit: Have a 12-hour reflective TNSS of at least 8 of 12 and a congestion score of 2 or 3 on Visit 1 * Randomization Visit: Have a 12-hour reflective TNSS (AM or PM) of at least 8 on 3 separate symptom assessments (one of which was within 2 days of Day 1, and can include the morning of Day 1) during the Lead-in Period. * Randomization Visit: Have an AM or PM 12-hour reflective nasal congestion score of 2 or 3 must have been recorded on 3 separate symptom assessments (one of which was within 2 days of Day 1, and can include the morning of Day 1) Randomization Visit: Have an instantaneous TNSS score of 8 or more at time point zero, just prior to beginning the onset of action assessment * Have taken at least 10 doses of the lead-in medication * Willing and able to comply with the study requirementsAt least a 2-year history of SAR during Fall allergy season * The presence of IgE-mediated hypersensitivity to a local Fall pollen, confirmed by a positive response to skin prick within the last year. A positive response is defined as a wheal diameter of at least 3 mm larger than the negative control. * General good health and free of disease or concomitant treatment that could interfere with the interpretation of the study results * Subjects receiving immunotherapy injections (antigen desensitization) must be on a stable maintenance regimen for at least 30 days before the first study visit * Subjects currently receiving sublingual immunotherapy are excluded. A 6-month washout period is required following the last dose of sublingual immunotherapy. Exclusion Criteria: * On Focused Nasal Examination, the presence of any superficial and moderate nasal mucosal erosion, nasal mucosal ulceration, or nasal septum perforation at either the screening visit or randomization visit * Other nasal disease(s) likely to affect deposition of intranasal medication * Nasal surgery or sinus surgery within the previous year. * Chronic sinusitis - more than 3 episodes per year * Planned travel outside of the pollen area during the study period * The use of any investigational drug within 30 days prior to Day -7. * Presence of any hypersensitivity to drugs similar to azelastine hydrochloride or fluticasone propionate * Women who are pregnant or nursing * Women of childbearing potential who are not abstinent or not practicing a medically acceptable method of contraception\* * Respiratory Tract Infections within 14 days prior to Day -7 * Respiratory Tract Infections requiring antibiotic treatment 14 days prior to Day -7 * Asthma (with the exception of intermittent asthma). * Significant pulmonary disease including COPD * Clinically significant arrhythmia or symptomatic cardiac conditions * A known history of alcohol or drug abuse within the last 2 years * Existence of any surgical or medical condition or physical or laboratory findings that could interfere with study result interpretation. * Patients with a history of Glaucoma * Clinically relevant abnormal physical findings within 1 week of randomization that may preclude compliance with the study procedures * Employees of the research center or private practice and their family members are excluded * Subjects who participated in protocol MP4001 or MP4002