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Phenylephrine hydrochloride modified-release tablets for nasal congestion: a randomized, placebo-controlled trial in
Eli O Meltzer1, Paul H Ratner2, Thomas McGraw3
1Allergy and Asthma Medical Group and Research Center, San Diego, California.
Background:
Over-the-counter phenylephrine hydrochloride (PEH) is used for relief of nasal congestion caused by allergic rhinitis; however, data to support its efficacy are lacking. The US Food and Drug Administration recommended clinical trials to evaluate the efficacy and safety of PEH in patients with this condition.
Objective:
To evaluate the efficacy and safety of PEH 30-mg modified-release (MR) tablets in patients with nasal congestion caused by allergic rhinitis in a multicenter, randomized, double-blinded, placebo-controlled, 2-arm, parallel-group study.
Methods:
Eligible adults at least 18 years old with documented hypersensitivity to fall pollen allergens were randomized to PEH-MR or placebo every 12 hours for 7 days from August 30 to October 12, 2011. The primary end point was mean change from baseline during the entire treatment period in daily reflective nasal congestion score. Secondary end points included changes in other symptom score assessments, time to maximal effect, duration of effect, and quality of life. Safety assessments included adverse events, serious adverse events, vital signs, physical examination, and electrocardiograms.
Results:
Of 575 patients, 288 received PEH-MR and 287 received placebo. No significant beneficial difference was detected between PEH-MR and placebo for the primary end point (PEH-MR, mean -0.394, SD 0.4880; placebo, mean -0.412, SD 0.5383; P = .2655). Likewise, no significant differences were observed for most secondary end points or quality of life. Overall, 89 of 575 patients (15.5%), equally distributed between the PEH-MR and placebo groups, experienced at least 1 treatment-emergency adverse event.
Conclusion:
PEH-MR 30-mg tablets taken orally every 12 hours for 7 days is not more efficacious than placebo in relieving nasal congestion caused by allergic rhinitis.
Trial Registration:
clinicaltrials.gov, identifier NCT01413958, protocol CL2011-06.
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