Ketamine Gets FDA Orphan Drug Designation for CRPS

By Pat Anson, PNN Editor

A Canadian biotech company has announced it has been granted orphan drug designation from the U.S. Food and Drug Administration to investigate the use of ketamine as a treatment for Complex Regional Pain Syndrome (CRPS)¸ a disorder of the nervous system that causes severe, intractable nerve pain. Currently, there is no FDA approved medication for CRPS.

Toronto-based PharmaTher Holdings specializes in the development of ketamine and other psychedelic drugs for mental health and pain conditions. The company also recently received an orphan drug designation for ketamine as a treatment for Amyotrophic Lateral Sclerosis (ALS), more commonly known as Lou Gehrig's disease.

“Receiving our second FDA orphan drug designation with ketamine for CRPS continues our momentum in building a specialty ketamine-based product pipeline for not only mental health disorders, but also for rare and near-rare conditions present in neurological, pain and inflammatory disorders,” Fabio Chianelli, CEO of PharmaTher, said in a statement.

Ketamine is not an opioid, but acts on pain receptors in the brain in a similar manner. Although the drug is only approved by the FDA for anesthesia and depression, a growing number of clinics provide off-label infusions of ketamine to treat difficult chronic pain conditions such as CRPS. In high-dose infusions, ketamine puts patients into a temporary dream-like state that can lead to hallucinations and out-of-body experiences.

The FDA first approved ketamine in 1970 and the medical patent on it expired years ago. The goal of PharmaTher is to develop its own propriety formulation of ketamine and expand its use. Orphan drug designation helps speed that process along by encouraging companies to invest in new uses for old drugs, often jacking up the price in the process.

If successful, PharmaTher says it would have seven years of exclusive marketing rights for its ketamine formulation, as well as potential tax credits and the waiver of $2.4 million in FDA filing fees.

In 2019, the FDA approved Spravato, a ketamine-based nasal spray developed by Janssen Pharmaceuticals, as a treatment for depression. A single dose of Spravato costs about $900.

“It seems they are doing something similar to what Janssen did with Spravato,” says Kimberley Juroviesky, a retired nurse practitioner who receives ketamine infusions for CRPS. Juroviesky co-chairs an advocacy group that’s trying to get more insurance coverage of ketamine.

“They are taking ketamine and changing it slightly to create a new drug. Then they can charge hundreds for it. We are hopeful though that maybe this can help us in our fight to get generic ketamine covered by insurance,” she told PNN in an email.

PharmaTher plans to launch a Phase 2 clinical trial of its ketamine formulation in 2022. In addition to treating CRPS, the company recently began a clinical study of ketamine as a treatment for Parkinson’s disease, and has filed a patent application for ketamine as a treatment for obesity and Type 2 diabetes. PharmaTher is also developing a microneedle patch for the delivery of ketamine and other psychedelic drugs.

While ketamine is emerging as a trendy pain reliever and many patients swear by it, medical societies urge caution. Guidelines from the American Society of Anesthesiologists, American Society of Regional Anesthesia and Pain Medicine, and the American Academy of Pain Medicine only support ketamine infusions for CRPS and post-surgical acute pain. The guidelines say there is no evidence supporting ketamine infusions for any other type of pain.

A 2019 study of nearly 300 patients who received ketamine infusions found that over a third reported significant side effects such as hallucinations and visual disturbances.