FDA-Approved Suzetrigine an Uncertain Painkiller

Vertex Pharmaceuticals has launched a new pain-reducing drug Journvax which has been approved by the FDA. The drug is being hailed as a health milestone by Dr. Jacqueline Corrigan-Curay (the acting director of the FDA’s Center for Drug Evaluation and Research), yet most of the patients demand more research, unsure about its long-term efficacy.

In many clinical trials, the drug has also shown a marked effect on reducing pain post-surgery. It can however mean fewer prescriptions and has been labeled as non-addictive by the experts. Also, known as suzetrigine, it could be used by patients who can’t take other pain relievers and has been approved to treat moderate to severe pain in adults.

At present, Doctors are left with fewer options to treat pain effectively. Medics like Michael Schatman, a clinical instructor in the department of anesthesiology, perioperative care and pain medicine at NYU Grossman School of Medicine and Dr. Richard Rosenquist, enterprise chairman in the department of pain management in the Neurological Institute at the Cleveland Clinic, do confirm the non-addictive part of the new find.

While pain is registered through the nerve endings throughout the body, drugs like acetaminophen (Tylenol) and nonsteroidal anti-inflammatory drugs, such as ibuprofen can’t do much. They might be effective in the initial stages, but after a certain point, proper drugs are needed which should be precise.

The addictive pathway of opioids is stimulated by opioid receptors in the brain. The neurotransmitter dopamine floods the brain which creates euphoric feelings while activating the brain’s reward system. That translates as opioids being addictive. Working by stimulating the opioid receptors in the brain, the former block the pain signals, arising anywhere in the body.

The drug, Suzetrigine works in a more precise way to block any one of the sodium channels which are found throughout the body and are responsible for pain signals to the brain. Many of them are critical for heart and brain functions, so the effectiveness of the drug can be seen during the blockage of only one specific channel, NaV 1.8.

Rosenquist is again optimistic about the non-addictive potential of the new pain-reducing drug. He says, “This is the first time we have had something that targets a specific sodium channel.” Added he, right now all the evidence suggests this has no addiction potential at all.”

More research is the need of the hour as many medics like Dr. David Rind, chief medical officer at the Institute for Clinical and Economic Review (ICER)___ a nonprofit group that evaluates the cost, safety and efficacy of drugs, are still unsure about the precise potential of the drug. In many patients who underwent Bariatric surgery, suzterigine was administered every 12 hours plus hydrocodone (an opioid) and Tylenol every six hours.

As a backup medicine, ibuprofen was also given to the patients, in case suzterigine didn’t work as it should. However, it is also a fact that the new drug comes with side effects like constipation alone as compared to any opioid, which comes with headaches, constipation or nausea. Also, 50% of people in the bunion surgery group and tummy tuck reported the latter as side effects.

However, pain reduction followed after the administration of suzterigine in 48 hours and was similar to the lesser pain reported in the case of Tylenol plus opioids given to the patients. In phase 3 trials led by Dr. Todd Bartech, chief medical officer for pain research at CenExel JBR Clinical Research in Salt Lake City, most of the non-surgical and surgical patients said that the drug was either good, very good or excellent in pain reduction. For a time period of 12 hours for 14 days, the drug was taken for pain reduction by the participants with a lower percentage of patients reporting various side effects.

What is agreed upon commonly by the ICER experts and Rind is that suzterigine shows promise but is still inconclusive due to their own uncertainty about the magnitude of the benefit provided apart from zero to no side effects. Besides, as per Rind, it also depends upon the toleration level of the drug in the patients, an apt instance being the cancer drugs which can’t outweigh the potential fatalities of the disease itself.  

Rind, again, says whether the drug should be taken in combination with other NSAIDs from the start to reduce the pain is still not clear, apart from the drug quantity itself. Bertoch also is of the opinion that the efficacy of the medication in solo or in combination after an administration of Tylenol and NSAIDs isn’t quite clear, though clinical trials have shown that the solo administration might be effective.

The drug can also be used by liver and kidney patients as well, for whom the NSAIDs aren’t safe, according to Bertoch. The rind also suggests having a wait-and-watch approach, as far as the efficacy of the drugs is concerned. And that, as per him, can only be gauged by the time when actually the drugs are in the market and used by the people.

According to him, there are apt candidates for confirming suzterigine efficacy, like gastrointestinal bleeding and addiction patients. For any medic, who would avoid prescribing opioids to these patients due to the dangerous nature of NSAIDs, suzterigine is an ideal choice. And also, according to Rind a large segment of the population does belong to the above two categories.

Rind again said that doubts about drug efficacy and long-term effects are still unclear areas, though, doctors with whom he has spoken are indeed excited about it. Dr Shatman of NYU Grossman School of Medicine and Dr. Holly Geyer, hospital internal medicine practitioner at the Mayo Clinic in Phoenix, both are of the opinion that in case of chronic pain reduction, the drug might not work at all.

Shatman who is also a senior medical adviser for Apurano Pharma, a German biotech company is working on a similar drug for pain reduction. He said, “There is relatively strong safety data for short-term use, and that is what the FDA requires.” He again said that Vertex wasn’t for FDA approval for suzterigine to treat chronic pain. Often doctors prescribe off-label medicines for pain management, which is worrying.

On the treatment of chronic pain, both have a different opinion. Shatman is concerned about Vertex’s absence of long-term data, while Geyer says that suzterigine works somewhat similarly to other drugs. And, according to her, the drug might not work in the former case, as it works on the peripheral nervous system which sends pain signals to the central nervous system and the drug blocks those. The central nervous system is responsible for chronic pain.

However, Rosequist says that despite the absence of further studies, the drug might find a place m in the market, but it all depends on the pricing. The doctors can prescribe the drug mostly in case of patients recovering, coming with fewer side effects, instead of the usual opioids.

Schatman said, “The bottom line is NSAIDs, generic opioids and acetaminophen are cheap,” adding that he hoped suzetrigine would be priced in a way that allows patients to access it.