Inclusion Criteria:

1. Male and female subjects 12 years of age and older
2. Provide written informed consent/pediatric assent. If the subject is a minor, a parent or legal guardian must give written informed consent

3. Subjects must have moderate-to-severe rhinitis, defined as rhinitis with one or more of the following being present:

   1. Sleep disturbance
   2. Impairment of daily activities, leisure and/or sport
   3. Impairment of school or work
   4. Troublesome symptoms
4. Screening Visit: Have a 12-hour reflective TNSS of at least 8 out of a possible 12 and a congestion score of 2 or 3 on Visit 1
5. Randomization Visit: For the 3 days prior to Randomization and on the morning of Randomization, the sum of the 7 consecutive reflective AM and PM TNSS assessments shall be equal to or greater than 56, with a nasal congestion score equal to or greater than 14
6. Randomization Visit: Have an instantaneous TNSS score of at least 8 and a congestion score of at least 2 at time point zero, just prior to beginning the onset of action assessment
7. Have taken at least 10 doses of the lead-in medication
8. Willing and able to comply with the study requirements
9. At least a 2-year history of SAR during the current allergy season
10. The presence of IgE-mediated hypersensitivity to a prevailing, individual, seasonal 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 an average of 5X5 mm larger than the negative control and a positive wheal of at least an average of 5X5 mm to histamine.
11. General good health and free of any disease or concomitant treatment that could interfere with the interpretation of the study results as determined by the investigator or the sponsor's medical officer. When in doubt, the investigator should confer with the sponsor's medical monitor or designee to determine eligibility for the study.

12. Subjects receiving immunotherapy injections (antigen desensitization) must be on a stable maintenance regimen for at least 30 days before the first study visit (adjustments to regimen following a brief period of missed injections do not preclude participation).

    Dose reduction when a new vial is used does not preclude participation.

13. Subjects currently receiving sublingual immunotherapy are excluded. A 6-month washout period is required following the last dose of sublingual immunotherapy.

Exclusion Criteria:

1. On Focused Nasal Examination, the presence of any superficial and moderate nasal mucosal erosion, nasal mucosal ulceration, or nasal septum perforation (Grade 1b - 4) at either the screening visit or randomization visit will disqualify the subject from the study.
2. Other nasal disease(s) likely to affect deposition of intranasal medication, such as sinusitis, rhinitis medicamentosa, clinically significant polyposis, or nasal structural abnormalities.
3. Nasal surgery or sinus surgery within the previous year.
4. Chronic sinusitis - more than 3 episodes per year
5. Planned travel outside of the pollen area during the study period
6. The use of any investigational drug within 30 days prior to Visit 1. No investigational products are permitted for use during the conduct of this study
7. Presence of any hypersensitivity to drugs similar to azelastine hydrochloride or fluticasone propionate
8. Women who are pregnant or nursing
9. Women of childbearing potential who are not abstinent or not practicing a medically acceptable method of contraception* see section 6.1.1
10. Respiratory Tract Infections within 14 days prior to Visit 1
11. Respiratory Tract Infections requiring antibiotic treatment 14 days prior to Visit 1
12. Asthma (with the exception of intermittent asthma). Subjects with intermittent asthma who only require short-acting inhaled bronchodilators (not more often than twice per week) and who do not have nocturnal awakening as a result of asthma are eligible for enrollment
13. Significant pulmonary disease including COPD
14. Clinically significant arrhythmia or symptomatic cardiac conditions
15. A known history of alcohol or drug abuse within the last 2 years
16. Existence of any surgical or medical condition or physical or laboratory findings, which in the opinion of the investigator or sponsor's medical monitor, might significantly alter the absorption, distribution, metabolism, or excretion of study drug; that might significantly affect the subject's ability to complete this trial; or their safety in this trial.
17. Patients with a history of glaucoma
18. Clinically relevant abnormal physical findings within 1 week of randomization which, in the opinion of the investigator, would interfere with the objectives of the study or that may preclude compliance with the study procedures
19. Employees of the research center or private practice and their family members are excluded
20. In order to ensure an adequate safety database, sites should make every effort to ensure no more than 50% of their subjects have participated in protocol MP4001, MP4002 or MP4004