In an Australian phase III trial (ONTRANS) reported in The New England Journal of Medicine, Allen et al found that 1 year of treatment with nicotinamide (vitamin B3) vs placebo did not reduce the risk of keratinocyte cancers or actinic keratoses in immunosuppressed solid organ transplant recipients. In the double-blind multicenter trial, 158 organ transplant recipients with two or more keratinocyte cancers in the past 5 years were randomly assigned between May 2017 and August 2019 to receive nicotinamide at 500 mg or placebo twice daily for 12 months. At 12 months, there were 207 new keratinocyte cancers in the nicotinamide group and 210 in the placebo group. The mean number of new keratinocyte cancers per patient was 2.6 vs 2.7. Also at 12 months, there were 69 vs 59 new basal cell carcinomas and 138 vs 151 squamous cell carcinomas.
May 24, 2023