Irish researchers set up the single centre, investigator-blinded STOP AD study (NCT03871998) that tested short-term emollient use for its capacity to prevent AD1. The 321, randomised, high-risk infants with a family history of AD were included from birth to ≤4 days. The intervention arm of the study immediately started an 8-week course with a ceramide dominant emollient at a dose of about 7 fingertip units applied twice daily. The control arm infants received standard skin care. During baseline and control visits at 2, 4, and 8 weeks, skin swabs, measuring of transepidermal water loss (TEWL), natural moisturising factor (NMF), and filaggrin testing were performed. The primary endpoint was the cumulative incidence of AD at 12 months. Secondary endpoints included AD at 6 months and the development of NMF and TEWL. Results have been published in Allergy2.
The mean infant age at baseline was just under 2 days and over 80% carried the wild type of filaggrin. Adherence in the intervention group was high with around 90% receiving daily emollient application at weeks 2,4, and 8. “People were very motivated, they knew what they were trying to prevent,” Prof. Alan Irvine (Trinity College Dublin, Ireland) commented. Use of emollients in the control group was low.
Reductions in AD risk were significant at 6 and 12 months with an RR of 0.524 (P=0.004) and 0.503 (P=0.002), respectively. Looking at cumulative AD at 12 months, Prof. Irvine highlighted that the biggest difference was noticed in the kids that had AD at 6 and at 12 months, while the intervention had already stopped at 8 weeks. Infants with a loss of function mutation in filaggrin were more prone to AD than the control group. “If we look at the intervention group and stratify by filaggrin, there is no additional risk of getting AD,” Prof. Irvine stressed and continued, “So, what we are seeing clearly here is a treatment-genotype-interaction.”
The researcher’s conclusion is that this significantly reduced AD incidence suggests short-term emollient application as a viable therapeutic model for risk reduction of AD in infancy.