Treating multiple AKs: Conservative treatment with topical imiquimod is safe, effective for organ transplant patients

September 1, 2008

Organ transplant patients must be particularly carefully examined and followed by their dermatologists, as this patient population is at an increased risk for developing multiple actinic keratoses in a short period of time. A recent study demonstrates that conservative treatment of these lesions with topical imiquimod is safe and effective.

Key Points

Berlin - Organ transplant patients who are treated with immunosuppressive drugs are much more susceptible to developing cutaneous malignancies and precancerous lesions compared to the healthy population.

These patients are known to develop multiple and large cancerous (basal and squamous cell carcinoma) and precancerous lesions (actinic keratoses [AKs]) in a very short time, and must be carefully followed by their physicians.

A recent study proves topical imiquimod 5 percent cream to be safe and effective in the treatment of multiple actinic keratoses in organ transplant patients.

"Our job as dermatologists is to closely follow these patients and employ an effective, and, especially, a safe treatment for these patients," Claas Ulrich, M.D., department of dermatology, Charité Clinic, Berlin, tells Dermatology Times.

Dr. Ulrich and a team of researchers conducted a multi-center, placebo-controlled study in 43 organ transplant patients (kidney, heart, liver) evaluating the safety and efficacy of topical imiquimod 5 percent cream in the treatment of multiple AKs.

Study details

Study participants were randomized 2 to 1 (active vs. vehicle) and advised to apply a total of 500 mg (two sachets) of topical imiquimod 5 percent cream or a vehicle cream three times per week to a defined 100 cm2 field of skin clinically diagnosed with AK on the face, forehead or balding scalp for a total of 16 weeks, regardless of clinical evidence of lesion clearance. A blinded, independent expert committee was responsible for safety monitoring and final safety assessment.

Study results

Study results showed that none of the patients had any graft rejections or any trends of deterioration of graft function, and laboratory parameters were found to be normal post-treatment.

Study patients who were randomized to imiquimod cream demonstrated a 75 percent clearance of their AKs.

Study patients who were randomized to receive a vehicle cream did not show any clearance, and as expected, they had a significant progression of their lesions.

Clearance rates were confirmed on histologic evaluation in all cases.

Dr. Ulrich says eight of the study participants (five imiquimod-and three vehicle-treated) reported a total of 11 serious adverse events during the trial; however, none of the adverse events were related to transplant rejection, nor were they considered to be related to the drugs studied.

Dr. Ulrich says other adverse events reported were generally uncommon and considered to be negligible.

"None of the patients in either the imiquimod group or the vehicle group experienced transplant rejection.

"These results are significant, because one of the endpoints of the study was to evaluate the safety of imiquimod in transplant patients, and according to our results, this immune-modulating drug has no serious effect on transplant patients."

Disclosure: This study was supported by 3M Pharmaceuticals.