Pretreatment with ablative fractional laser changes kinetics and biodistribution of topical 5-Aminolevulinic acid (ALA) and its methylated ester, methyl aminolevulinate (MAL), new research suggests.

The findings appear in the August 2014 issue of Lasers in Surgery and Medicine (LSM). Laser-assisted drug delivery (LADD) is an evolving technology which has a potentially wide range of clinical uses that are currently being studied, including the delivery of systemic medications, and potentially stem cells and growth factors.

By disrupting the skin barrier with ablative fractional laser channels, the researchers impaired the skin barrier function and introduced an alternative way for uptake of topically applied photosensitizers, which significantly increased fluorescence intensities and altered the biodistribution and kinetics of ALA and MAL.

Laser-assisted drug delivery (LADD) is an evolving technology which has a potentially wide range of clinical uses that are currently being studied, including the delivery of systemic medications, and potentially stem cells and growth factors.

“Using different photosensitizers for laser-assisted intensified photodynamic therapy may give us opportunities to customize PDT to target specific skin lesions,”writes researcger Merete Haedersdal, MD, PhD, DMSc, a dermatologist and associate clinical professor of dermatology at the University of Copenhagen, Denmark.

“The research shows that pretreatment with ablative fractional laser considerably enhances the amount of porphyrin fluorescence from ALA and MAL photosensitizers,” says Editor-in-Chief of LSM J. Stuart Nelson, M.D., Ph.D. “This study presents new information that ALA and MAL behave differently on AFXL-processed skin. Thus MAL expresses higher fluorescence than ALA for short-term application, whereas ALA over time overcomes MAL and induces the highest fluorescence intensities obtained.”