They randomized thirty six patients with dysplastic Barrett's esophagus who were receiving acid suppression medication with omeprazole to receive oral 5-aminolaevulinic acid (ALA) 30 mg/kg or placebo, followed four hours later by laser endoscopy. Follow up endoscopy was performed at one, six, 12, and 24 months.
Of 18 patients in the ALA group, a response was seen in 16 (median decrease in area in the treated region 30%; range 0-60%).In the placebo group, a decrease in area of 10% was observed in two patients with no change in 16 (median 0%; range 0-10%; treatment v placebo, p<0.001).
Whilst no dysplasia was seen in the columnar epithelium within the treatment area of any patient in the PDT group, persistent low grade dysplasia was found in 12 patients (p<0.001) in the placebo group.
"ALA induced PDT can provide safe and effective ablation of low grade dysplastic epithelium."
Prof. M W R Reed.
There were no short or long term major side effects. The effects of treatment were maintained for up to 24 months.
In this first randomized controlled trial of PDT for Barrett's esophagus Professor Reed concluded, "It demonstrates that ALA induced PDT can provide safe and effective ablation of low grade dysplastic epithelium."