The results, published recently in the New England Journal of Medicine, find the drug, marketed as Lyrica, appears to be no better than placebo.
Australian researchers from The George Institute for Global Health also point out that patients prescribed pregabalin reported nearly twice as many adverse effects as those receiving the placebo.
“We have seen a huge rise in the amount of prescriptions being written each year for patients suffering from sciatica,” explained co-author Christine Lin, PhD, from The George Institute for Global Health. “It's an incredibly painful and disabling condition so it’s no wonder people are desperate for relief, and medicines such as pregabalin have been widely prescribed.
“But, until now there has been no high quality evidence to help patients and doctors know whether pregabalin works for treating sciatica. Our results have shown pregabalin treatment did not relieve pain, but did cause side effects such as dizziness.”
Background information in the article notes that, since its first approval in 2004, pregabalin has become the most widely prescribed medicine for neuropathic pain globally, with worldwide sales of $3 to $5 billion annually.
To determine effectiveness, a randomized, double-blind, placebo-controlled trial in 209 patients with sciatica was conducted, with participants randomly assigned to receive either pregabalin at a dose of 150 mg per day that was adjusted to a maximum dose of 600 mg per day, or matching placebo, for up to 8 weeks.
Results indicate that, at Week 8, the mean unadjusted leg-pain intensity score was 3.7 on a 10-point scale in the pregabalin group and 3.1 in the placebo group. At Week 52, the mean unadjusted leg-pain intensity score was 3.4 in the pregabalin group and 3.0 in the placebo group.
While no significant differences were observed for any secondary outcome—the extent of disability, back-pain intensity, and quality-of-life measures—at either Week 8 or Week 52, 227 adverse events were reported in the pregabalin group and 124 in the placebo group. Among them was dizziness, which was found to be more common in the pregabalin group than in the placebo group.
“Over the course of eight weeks the levels of pain that patients experienced did decrease but the drop in pain was the same for both those taking the drug and those on placebo,” Linn said. “It seems people associate a drop in pain being due to taking a capsule, rather than something which would happen naturally over time.”
She urged prescribers to note the findings and seek alternative ways of managing and preventing pain, adding, “Unfortunately there are no drugs proven to work for people with sciatica and even epidural injections only provide a small benefit in the short term.”