Study to Compare the Pharmacokinetics of Fixed-Dose Combination of Mometasone + Azelastine Nasal Spray to Mometasone and Azelastine Nasal Sprays in Adolescents and Young Adults With Seasonal Allergic Rhinitis

Inclusion Criteria: 1. Non-smoking, adolescent or young adult male and female subjects with seasonal allergic rhinitis. 2. Willing to use acceptable, effective methods of contraception. 3. Be informed of the nature of the study and give written consent (adults) / assent and consent by legal guardian(s)/parent(s) (adolescents) prior to any study procedure. Exclusion Criteria: 1. Known history or presence of clinically significant disease or any other condition which, in the opinion of the Investigator, would jeopardize the safety of the subject or impact the validity of the study results. 2. Known history or presence of hypersensitivity or idiosyncratic reaction to mometasone, azelastine, or any other drug substances with similar activity. 3. Unable to tolerate direct venipuncture. 4. Positive test result for HIV, Hepatitis B surface antigen, or Hepatitis C antibody. 5. Positive test result for urine drugs of abuse or urine cotinine. 6. Presence of nostril or septum piercing. 7. Use of tobacco or nicotine-containing products within 6 months prior to drug administration. 8. Females who are pregnant, breast-feeding, or have used hormonal contraceptives within 21 days (oral and transdermal) or 6 months (implanted, injected, intravaginal, or intrauterine) prior to drug administration. 9. Donation or loss of whole blood (including clinical trials) within 30 days prior to drug administration (or 56 days for ≥500 mL). 10. Participation in a clinical trial that involved administration of an investigational medicinal product within 30 days prior to drug administration, or recent participation in a clinical investigation that, in the opinion of the Investigator, would jeopardize subject safety or the integrity of the study results. 11. Received any type of live vaccine within 30 days prior to drug administration. 12. Use of medication within 30 days prior to drug administration. 13. On a special diet within 30 days prior to drug administration. 14. Have had a tattoo or body piercing within 30 days prior to drug administration.