Pregabalin (Lyrica) is not effective in controlling the chronic pain that sometimes develops following traumatic nerve injury, according to a study published in the Journal of Neurology.
The results of the international study, which was driven by an effort to identify effective non-opioid pain medications, did show potential in relieving in pain that sometimes lingers after surgery.
“The unrelenting burning or stabbing symptoms due to nerve trauma are a leading reason why people seek treatment for chronic pain after a fall, car accident, or surgery,” said lead author John Markman, MD, University of Rochester, Rochester, Minnesota. “While these finding show that pregabalin is not effective in controlling the long-term pain for traumatic injury, it may provide relief for patients experience post-surgical pain.”
A previous 8-week study had shown that pregabalin reduced pain intensity better than placebo in these chronic, post-traumatic pain syndromes. This led many doctors to prescribe this medication for long-term pain that does not resolve as expected.
Chronic postsurgical pain syndromes occur in approximately 1 or 2 out of every 10 surgical patients and the levels rated as intolerable after roughly 1 or 2 in every 100 operations.
The current study was conducted in 101 centres in in North America, Europe, Africa, and Asia and followed 539 individuals for 3 months. Study participants were randomised to receive either pregabalin or a placebo.
The study found that pregabalin was not effective in controlling pain for individuals with traumatic nerve injury. A retrospective analysis of a subgroup of study of participants, whose nerve pain was attributed to surgery, showed that the drug did provide better pain relief than placebo at 3 months.
“The possibility that there was pain relief for those patients who had a hernia repair, or breast surgery for cancer, or a joint replacement lays the groundwork for future studies in these post-surgical syndromes where there is so much need for non-opioid treatments,” said Dr. Markman.
One major challenge is that different biological changes in the nerves and other tissues that cause pain to persist after healing from trauma vary from one patient to the next. Currently, there is no diagnostic method that allows doctors to readily identify the patients whose pain will respond to a particular type of pain treatment.
Despite employing new strategies to reduce placebo effects, the patients receiving placebo also had a steady lowering of their pain over the course of the study. The pattern of these placebo effects in longer studies has proved to be a major challenge to the development of new pain medications.
“Given the rising rates of surgery and shrinking reliance on opioids, it is critical that we understand how to study new drugs that work differently in patients like the ones included in this study,” said Dr. Markman.