To examine the relative potency, onset of action and duration of action of fexofenadine HCl
180 mg (ALLEGRA) and desloratadine 5 mg (CLARINEX) as compared to placebo on skin wheals and
flares induced by histamine.
Inclusion Criteria:
- Male and female subjects, 12 to 55 years of age, may participate
- Positive histamine skin prick tests (or duplicate histamine skin prick test) with a
summation flare (ΣF) greater than or equal to 20 mm larger than diluent control, and
summation wheal (ΣW) greater than or equal to 6 mm larger than diluent control at the
screening visit 1
- All female subjects must have a negative urine pregnancy test at the screening visit
- Female subjects who are sexually active will be expected to use one of the following
birth control methods throughout the study (see Section 4. 4)
- Subjects must be within 15% of normal body weight for height or a BMI less than 29. 9
(based on NHLBI guidelines)
- Subjects willing and able to adhere to visit schedules and all study requirements
- All female subjects must have a negative urine pregnancy test at each treatment visit
(Visit 2, 4, and 6).
- Continues to meet all inclusion and exclusion criteria
Exclusion Criteria:
- Asthma that requires treatment with medication other than an inhaled, short-acting
beta agonist
- Signs and symptoms of currently active allergic disease (seasonal allergic rhinitis,
perennial allergic rhinitis, episodic allergic rhinitis)
- Upper respiratory tract infection, sinusitis, asthma or flu-like symptoms within 2
weeks prior to visit 1
- Subjects who have dermatographism or other skin conditions which might interfere with
the interpretation of the skin test results
- Subjects who are receiving immunotherapy
- Any excessive amounts of alcohol (no more than two drinks/day on average)
- Any excessive use of caffeine (more than six cups of coffee per day or equivalent)
- Any use of tobacco/nicotine products within 90 days of visit 1
- Any disease state or surgery known to affect the gastrointestinal absorption of drugs
- Known hypersensitivity to the investigational product or to drugs with similar
chemical properties
- Subjects who will be visiting a tanning salon during the study
- Subjects who will need to use artificial tanning products during the study
- Night or variable shift workers during the study
- Pregnancy
- Breast-feeding
- History of hypersensitivity to the study medications or to drugs with similar chemical
structures
- Treatment with other H1-receptor antagonists in the last year before study entry
- Likelihood of requiring treatment during the study period with drugs not permitted by
the clinical study protocol (see Section 6. 2)
- Treatment with any investigational product in the last 30 days before study entry
- No person or child of a person directly associated with the administration of the
study may participate as a study subject
- Clinically relevant cardiovascular, hepatic, neurologic, endocrine, or other major
systemic disease making implementation of the protocol or interpretation of the study
results difficult
- Mental condition rendering the subject unable to understand the nature, scope, and
possible consequences of the study
- Subject unlikely to comply with protocol, e. g., uncooperative attitude, inability to
return for follow-up visits, and unlikelihood of completing the study
- Use of any of the following drugs within the time indicated prior to the first dosing
visit:
