Non-melanoma skin cancers (NMSCs), which include basal cell carcinomas (BCCs) and cutaneous squamous carcinomas (SCCs), are the most common malignancy in the U.S.; it is estimated that \>3.5 million new NMSCs this year. This represents a tremendous economic impact on the U.S. healthcare system. Most NMSC are caused by overexposure to ultraviolet radiation, and current methods for their prevention consist of recommendations for limitations to sun exposure and avoidance of indoor tanning beds, the regular application of sunscreens, and a variety of other photoprotective activities. Despite these measures, the incidence of NMSCs continues to rise.
NMSCs are a particular problem for organ transplant recipients (OTRs), who must take medicines to protect against rejection of their transplanted organ. These drugs suppress the host immune response that serves to identify and eliminate mutant and neoplastic keratinocytes before they can progress to clinically apparent cancers. Recent research indicates that these drugs also augment signal transduction pathways involved in skin tumor development. NMSCs develop much more frequently in long-term recipients of renal allografts and once present, they behave more aggressively. In immunosuppressed patients, the risk of developing SCCs is 65250-fold higher than in the general population, and the risk of BCCs is 10-fold greater. The rate of SCC metastases in organ transplant recipients is 7%, which is much higher than the general population. For this reason, there has been great interest in identifying novel agents for chemoprevention, which are suitable for use by OTRs.
There will be two groups to the study. Individuals, aged 18 years or older, who have had a renal transplant but are in otherwise general good health, will be given UAB30 (160 mg/day) and will be compared to individuals, aged 18 years or older, who have had a renal transplant and are in otherwise general good health who are given placebo. All participants must be at increased risk of non-melanoma skin cancer as evidenced by a history of prior squamous or basal cell skin cancer, ongoing or history of actinic keratoses, and the presence, at baseline, of at least eight actinic keratoses on the face, neck, scalp and arms. Subjects will be randomized to 28 days of:
1. UAB30 at 160 mg/day, renal transplant recipients
2. placebo renal transplant recipients
At baseline screening, informed consent will be obtained and skin will be examined for potential non-melanoma skin cancers. Any lesions that are clinically suspicious for non-melanoma skin cancer will be removed per standard of care prior to administration of drug. Actinic keratoses will not be removed during the 28 day study period. Two weeks later, once any lesions clinically suspicious for non-melanoma skin cancer have been removed, renal transplant recipients will be randomized to one of the treatment arms described above. Participants will return at 28 days and 112 days for assessment.
1. At randomization and 28 days, 6mm punch biopsies, or the equivalent deep shave biopsies, will be taken for individual biomarkers from non-sun exposed skin, chronically sun exposed skin, and a pre-identified AK. The chronically sun-exposed skin to be biopsied will be no less than 1 cm from the AK to be biopsied.
2. At baseline, at 28 days and at the end of study AK lesions will be assessed and counted, employing techniques that have been validated in other studies.
3. All lesions suspicious for skin cancer will be biopsied and treated appropriately (per standard of care) throughout the study.
4. Adverse events will be assessed, including NMSC and melanoma, from signing of the informed consent through the end of the trial.
