They make a painkiller that's smarter and less addictive than opioids.

An experimental drug could offer powerful pain relief without the dangerous side effects of opioids.

The drug, called SBI-810, is part of a new generation of molecules designed to act on a receptor in the nerves and spinal cord. While opioids indiscriminately target multiple cellular pathways, SBI-810, a non-opioid treatment , takes a more targeted approach, activating only a specific pain-relief pathway, thereby avoiding the euphoria associated with addiction.

In mouse experiments, SBI-810 worked well on its own and, when used in combination, made opioids more effective at lower doses, according to the study published in the journal Cell .

"What makes this compound exciting is that it's both an analgesic and a non-opioid," said senior study author Ru-Rong Ji, an anesthesiology and neurobiology researcher who directs the Duke University Anesthesiology Center for Translational Pain Medicine.

Even more encouraging: It prevented common side effects like constipation and tolerance buildup, which often requires patients to require stronger and more frequent doses of opioids over time.

Although SBI-810 is in an early stage of development, researchers aim to conduct a human clinical trial soon.

There is an urgent need for alternatives to relieve pain.

Researchers say the drug could be a safer option for treating chronic, short-term pain in those recovering from surgery or living with diabetic nerve pain.

SBI-810 is designed to target the brain's neurotensin-1 receptor. Using a method known as biased agonism, it activates a specific signal, β-arrestin-2, linked to pain relief, while bypassing other signals that can cause side effects or addiction.

"The receptor is expressed in sensory neurons, the brain, and the spinal cord," Ji says. "It's a promising target for the treatment of acute and chronic pain."

SBI-810 effectively relieved pain caused by surgical incisions, bone fractures, and nerve injuries, better than some existing painkillers. When injected into mice, it reduced signs of spontaneous discomfort, such as guarding and facial grimacing.

Duke scientists compared SBI-810 to oliceridine , a newer type of opioid used in hospitals, and found that SBI-810 worked better in some situations, with fewer signs of distress.

The researchers write that the compound's dual action (on the peripheral and central nervous systems) could offer a new kind of balance in pain medicine: potent enough to work, yet targeted enough to prevent damage.