Pregabalin improves recessive dystrophic epidermolysis bullosa pain

Key takeaways:

• Pregabalin targets the a2-delta auxiliary subunit of voltage-gated calcium channels.
• Patients with RDEB in this small trial experienced improvements in both pain and itch after pregabalin treatment.

Patients with recessive dystrophic epidermolysis bullosa experienced a reduction in pain and itch with pregabalin treatment, according to small study.

“Epidermolysis bullosa (EB) is a genetic mechanobullous disorder characterized by skin fragility and blistering from minor friction,” Margarita Calvo, MD, PhD, associate professor in the department of physiology at Pontifical Catholic University, and colleagues wrote.

In recessive dystrophic epidermolysis bullosa (RDEB), a subtype of EB caused by variants in COL7A1, pain and itch are the most predominant symptoms, they added.

This randomized, double-blind, crossover feasibility trial of pregabalin, which targets the a2-delta auxiliary subunit of voltage-gated calcium channels, enrolled 10 patients at two centers who were randomly assigned to one of two treatment groups.

The 24-week trial included four phases: a 2-week washout period; a 10-week period where group 1 (n = 6) received daily pregabalin (50 mg to 300 mg) and group 2 (n = 4) received placebo; a 2-week washout period; and a 10-week period where group 1 received placebo and group 2 received daily pregabalin.

Pain levels measured by VAS were reduced in each group following pregabalin treatment, with pooled data showing a mean pain score of 4.1 for those in the treatment groups and 5.9 in the placebo groups.

After adjusting for sequence and treatment period, a mixed regression model showed a statistically significant reduction from baseline of 2 points in the treatment groups and 0 in the placebo groups (beta = 1.6; P < .001; standard error [SE] = 0.58).

Itch scores were 4.3 in group 1 and 5.4 in group 2 following placebo, compared with 3.8 and 4.3 following pregabalin, respectively. This reduction was small but significant, according to the mixed model (beta = 0.93; P < .05; SE = 0.41).

Quality of life improvements were also recorded, with five pregabalin users reporting at least a 30% improvement in pain and three reporting at least a 50% improvement.

“This randomized crossover trial found a potential benefit of pregabalin in reducing pain and/or itch in patients with RDEB,” the authors wrote. “Larger well-powered studies are needed to validate these preliminary results.”