Use of Dapsone Gel, 5% for Treating Dermatitis Herpetiformis

The study will be a prospective evaluation of dapsone gel, 5% in patients with a clinical
diagnosis of dermatitis herpetiformis. Active disease must occur on the patients' bilateral
elbows or bilateral knees at the time of study enrollment. Active disease will be defined as
five or more papules/pustules/vesicles on an extremity. Randomization of one of the patient's
extremities (either one elbow or one knee) to the treatment group will occur at time of
enrollment. Randomization will be in the sequence of right side assigned to odd numbered
patients and left side assigned to even numbered patients. Thus, the first patient to be
enrolled, patient number one, would be randomized to treatment on his or her right side.
Depending on the site of active disease, he or she would apply topical dapsone gel, 5% to the
right elbow or knee twice daily for the duration of the study.

No blinding of the patients or the PI will occur. The co-investigator will be blinded to
whether the photographs presented to him at the end of the study are those of a treated or
untreated extremity.

The patients will be screened for study enrollment in a private clinic room within the
dermatology clinic at One Hundred Oaks. Patients will be presented with a study summary sheet
and a consent form. They will be allowed to ask questions pertaining to the study protocol.
Information provided to them will be that found in the study protocol alone. If desired,
informed consent can be taken home with the patient to consider, and enrollment can be
performed at a later date. In that instance, the patient would be brought back for an
additional visit at the time of consent and study enrollment. Study enrollment and first
treatment will be performed on the day of study consent. Digital photographs of each elbow or
each knee (treatment and control) will be taken on the day of enrollment to serve as a
baseline evaluation. The number of lesions (including papules, plaques and vesicles) will be
recorded for the treatment and control elbow or knee. Measurements of each lesion will be
taken and recorded as well. This data will be written in a chart and stored in the PI's
notebook in a locked cabinet in the department of dermatology. Digital photographs will be
printed out on the same day as the visit and placed in the notebook as well. Two copies of
each photograph will be made. Each photograph will be assigned a letter, A through Z, based
on a code for each patient. One copy of each set of photographs will also include the date.
No patient identifiable features will be included in the photograph such as the face or eyes.
Each photograph will be of the treated or control area only. The code to identify patient
photographs will be assigned by the Data and Safety Monitor and kept in a separate locked
cabinet. The code will be broken following the blinded evaluation of the photographs by
co-investigator.

The patient will be given oral instructions regarding the application of topical dapsone gel,
5% by the PI on the day of enrollment. The PI will apply the first treatment to the
randomized extremity during the first clinic visit. The patient will then remain in the
treatment room for fifteen minutes to evaluate for any immediate adverse reaction. The PI
will remain in the room with the patient. At the end of the fifteen minute evaluation, the
patient will be sent home with written instructions for application and a 30gm tube of
ACZONE™ (dapsone) Gel, 5%. Patients will apply the study drug to the indicated elbow or knee
each morning and evening for the two weeks. They will return to the dermatology clinic in two
weeks and be seen in a private clinic room by the PI for a follow up visit. At that time,
photographs, lesion counts and measurements will be taken again, just as they were at the
initial visit. The patient will be asked to report any adverse events at that time. Patients
will be instructed to continue treatment and follow up in two weeks. The same parameters will
be evaluated at the four week visit and again at the six week visit, which will be the
completion of the study.

Patients will discontinue treatment after six weeks. The co-investigator will be presented
will all photograph marked with the patient letter only. He will not know the sequence of the
photographs or dates taken. He will then assign a number according to his subjective
evaluation of the clinical photographs, while also being blinded to which elbow or knee was
treated, right or left. The scores assigned will follow the criteria listed in the
investigator's Dermatitis Herpetiformis Assessment Score. The code to the photographs will be
broken after the completion of photograph evaluation. Photographs of a set will be matched to
those with both letter and date to determine the scores in chronological order.

Six weeks after completion of treatment each patient will be contacted by phone and asked a
series of five questions. That will conclude the study.

Inclusion Criteria:

- Age 12 years or older

- Clinical diagnosis of dermatitis herpetiformis, as previously diagnosed by the
patient's primary dermatologist or diagnosed by agreement of the two investigators

- Active disease at time of enrollment, defined as at least five inflammatory lesions
(to include papules, plaques and vesicles) on the bilateral elbows or bilateral knees

Exclusion Criteria:

- Patients taking oral dapsone or those who have taken oral dapsone within four weeks
prior to enrollment

- Patients using any other topical treatment for dermatitis herpetiformis at time of
enrollment or within the four weeks prior to enrollment

- Patients with known allergy or hypersensitivity to dapsone, sulfa drugs or excipients
of the dapsone gel product

- Women will be excluded if pregnant or nursing

- Women of childbearing potential must be practicing an effective method of birth
control as determined by the enrolling physician. If oral contraceptives are the
method of choice, then the patient must have been on a stable dose for a minimum of 3
months. (This is the same guideline used for women of childbearing potential in
previous studies of acne patients.)