A Study to Assess Menstrual Cramp Pain Associated With Primary Dysmenorrhea

Inclusion Criteria:

• Ambulatory healthy female patients between 15 and 35 years of age;

• Patient has a history of Over-the-Counter (OTC) analgesic use for treatment of primarydysmenorrhea;

• Patient has a history of regular menstrual cycles that typically occurs between every 21 to 35 days;

• Patient has a self-reported history of primary dysmenorrhea (onset <5 years aftermenarche) with at least moderate menstrual cramp pain (based on the categorical painintensity scale, 0-3) occurring during four of the past six menstrual cycles;

• Patient has a self-reported history of primary dysmenorrhea with other causes ofdysmenorrhea having been excluded;

• Patient typically requires at least one dose of an OTC analgesic medication such asnaproxen, aspirin, acetaminophen, or ibuprofen taken on at least 1 day of hermenstrual cycle for the treatment of moderate or severe menstrual cramp, and normallyexperiences pain relief from these medications;

• Patient is of child-bearing potential and is using one of the following methods ofcontraception and agrees to continue this same method for the duration of the study:

• Abstinence for at least the last 60 days AND willingness to use double barriermethod should the patient become sexually active during the study;

• Double barrier method (condom with contraceptive foam, diaphragm withcontraceptive gel);

• Permanent sterilization of patient or her spouse/partner;

• Oral contraceptive (must have been using the same oral contraceptive for at leastthree months prior to study entry and agrees to remain on the same type andmethod throughout the course of the study).

• Patient is willing to participate in the study and return to the study site withinapproximately 1 week after her menstrual cycle to return the study medication, urinepregnancy test, and for review of the completed patient e-diary;

• Patient is willing to abstain from alcohol consumption throughout the 12-hourTreatment Period;

• Patient is willing to abstain from caffeine consumption throughout the 12-hourTreatment Period;

• Patient is willing to ingest the overencapsulated tablets throughout the study;

• Patient is willing and able to participate in all scheduled visits, treatment plan,laboratory tests and other study procedures according to the clinical protocol.

Exclusion Criteria:

• Patient has a known history of allergic, idiosyncratic or serious adverse reaction, toacetaminophen, naproxen, aspirin, ibuprofen, or any other nonsteroidalanti-inflammatory drug (NSAID);

• Patient has a known allergy to any of the excipients in any of the study medicationproducts;

• Patient has experienced asthma, urticaria, or allergic-type reactions after takingaspirin, acetaminophen or other NSAIDs;

• Patient has significant co-existing illness, including gastrointestinal, hepatic,renal, neurologic, cardiovascular, psychiatric, endocrine, respiratory, surgicalprocedure or other condition that, in the Investigator's judgment, contraindicatesadministration of the study medication;

• Patient has a current or past history of severe gastritis, gastrointestinal bleedingor ulceration;

• Patient has a current or past history of one or more of the following conditions:secondary dysmenorrhea, pelvic inflammatory disease, urinary tract infection (currently acute or recurrent [defined as more than three per year] prior history ofan urinary tract infection is eligible for enrollment), adnexal masses, uterinefibroids, endometriosis, adenomyosis that in the opinion of the Investigator wouldimpact patient safety and/or the study data;

• Patient has an ongoing sexually transmitted disease (except for a history of genitalherpes or Human Papillomavirus) or has abnormal vaginal discharge;

• Patient requires prescription analgesics, narcotic, non-NSAID (i.e., defined as oraluse of 5 or more times per week for greater than 3 weeks) or has routinely taken OTCmedications in excess of label recommended instructions for control of dysmenorrheasymptoms;

• Patient is taking mood-altering agents (e.g., antidepressants, sedatives,phenothiazines, or anti-anxiety agents). Patients who are on a stable dose for atleast 3 months, and not taking this medication for dysmenorrhea or premenstrualsyndrome are eligible for enrollment;

• Patient does not agree to abstain from taking any analgesic and/or anti-inflammatorymedication (with the exception of low dose aspirin [defined as no greater than 100 mgdaily] taken for cardioprotective purposes) approximately 72 hours prior to theanticipated treatment period and throughout the dosing/assessment period. All pain andanti-inflammatory medications including supplements, topical heat or cold, and otherproducts of topical application will be discontinued approximately 72 hours prior tothe anticipated dosing for each treatment period and throughout the dosing/assessmentperiod;

• Patient does not agree to abstain from using transcutaneous electrical nervestimulation devices that are used to treat dysmenorrhea throughout each treatmentperiod;

• Patient is taking piroxicam (Feldene®) or oral corticosteroids. Patients takinginhaled or topical corticosteroids are eligible for enrollment;

• Patient is pregnant, lactating , or less than 6 months postpartum;

• Patient is currently using an intra-uterine devices (IUD), or using hormonal implants (e.g., Norplant) or injections (e.g., Depo-Provera) for contraception or used withinthe past 6 months;

• Patient is currently using an oral contraceptive for less than 3 months, has been on aunstable dose within the last 3 months or has switched from one oral contraceptive toanother within the last 3 months or intends to do so in the course of the study;

• Patient has a history of chronic abuse of alcohol (regularly consumes 3 or morealcoholic drinks per day), analgesics, narcotic analgesics, ergot alkaloids,tranquilizers, or opioids or other substances known to produce dependence; in thejudgement of the investigator within the past 3 years;

• Positive drug at screening and visit 2 for illegal drug substances, or non-prescribedcontrolled substances;

• Positive pregnancy test or breast feeding at screening and prior to dosing in eachTreatment Period;

• Patients with a medical disorder, condition or history such that could impair thepatient's ability to participate or complete this study in the opinion of theinvestigator.