Blow to nicotinamide’s role in reducing skin cancer in organ transplant recipients

Australian researchers have found no ‘convincing evidence’ that oral nicotinamide reduces the risk of skin cancer in immunosuppressed solid organ transplant recipients.

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The use of oral nicotinamide for skin cancer chemoprevention in solid organ transplant recipients is ineffective, Australian researchers have found.

Immunosuppressed organ transplant recipients are at about 50 times higher risk of incidence and mortality from skin cancer than the general population.

The researchers have published their findings from the phase III trial in the New England Journal of Medicine.

Lead author, Professor Diona Damian, head of Dermatology at the University of Sydney, Royal Prince Alfred Hospital, told Dermatology Republic it was a disappointing but important finding.

“The bottom line is this group of patients, who are chronically immune-suppressed and have had transplants, are in dire need of better and more effective ways to reduce the numbers of skin cancers,” she said.

“Skin cancer is common enough in Australia, but when your immune system is no longer there to defend you against skin cancers, they grow at an enormously elevated rate. So, we’re in desperate need of something.”

Professor Damian said they knew from previous work in people with normal immune systems, nicotinamide was effective in helping to reduce how many skin cancers they grew.

“This needed to be looked at to see it if would work in people who don’t have a functional immune system,” she said.

“The upshot of this study was that we did not find any convincing evidence that it can be protective against skin cancer development in people who have had transplants and are on huge amounts of industrial strength immune suppression.”

Professor Damian told DR there were some limitations to the study, including the fact that they didn’t reach target recruitment.

“Recruitment was a lot slower than we’d anticipated possibly because a lot of our potential participants were already taking the nicotinamide, having heard about it, or their physicians had heard about our previous studies,” she said.

“A lot of the people who may have been eligible for our study were already on nicotinamide and therefore could not participate, so we didn’t reach target recruitment and that’s a limitation.

“But it was the study across sites in Queensland, sites in New South Wales and Victoria and South Australia. So, there’s a multicentre study, and there was not even a little signal really, for effectiveness.”

A total of 158 participants were enrolled, with 79 assigned to the nicotinamide group and 79 to the placebo group.  At 12 months, there were 207 new keratinocyte cancers in the nicotinamide group and 210 in the placebo group.

“No significant between-group differences in squamous-cell and basal-cell carcinoma counts, actinic keratosis counts, or quality-of-life scores were observed,” the authors wrote.

“Adverse events and changes in blood or urine laboratory variables were similar in the two groups.”

Professor Damian said it was possible that a larger study which focused only on the most common sorts of skin cancers in these patients might find some evidence for effectiveness.

“There is a Canadian group in particular who have a larger study slowly progressing, so that in addition to what we’ve done may give us more information,” she said.

“But the punchline from our study is that first of all, we don’t have any evidence that this is something that’s worth taking if you’re a transplant recipient. At the same time, we didn’t find any evidence of harm, which is a good thing.”