No use of NSAID's (including aspirin) or oral adrenocorticosteroids, at any dose at a frequency averaging greater than 3 times per week during the six months prior to study entry. Use of such NSAID's or oral adrenocorticosteroids at the above frequency will require a six-month washout period prior to eligibility, beginning with the time of the patient's last dose. Use of any dose of NSAID's or oral adrenocorticosteroids, at an average frequency of 1-3 times per week during the six months prior to study entry will require a three-month washout period beginning with the time of last dose.