Tulane scientist working on powerful new non-addictive painkiller _lowres

Photo by Paula Burch-Celentano. -- James Zadina, VA senior research career scientist and professor of medicine, pharmacology and neuroscience at Tulane University School of Medicine. “It’s unprecedented for a peptide to deliver such powerful pain relief with so few side effects.”

With heroin and opiate-related deaths on the rise nationally, and 43 deaths from heroin overdoses reported last year in New Orleans alone, scientists at Tulane University and the Southeast Louisiana Veterans Health Care System may be on the brink of creating a new painkiller that would not be addictive and would have fewer side effects.

The drug, which would be used as an alternative to morphine and other opium-based drugs, has the potential to prevent overdoses by lowering addiction.

James Zadina, a professor of medicine, pharmacology and neuroscience at the Tulane School of Medicine, said the new peptide-based drug is “unprecedented” in that it targets the same pain-relieving opioid receptor as morphine, but without side effects like motor impairment, respiratory depression and increasing tolerance, which means people need larger and larger amounts to achieve the same level of relief.

Often, he said, people who overdose from drugs like heroin became addicted because doctors first prescribed them opiates like Vicodin or Percocet. Yet some patients are still forced to live with pain because the danger of prescribing higher doses of opiates is too great — a dilemma Zadina hopes to eradicate in coming years with his new drug.

“Many people still have their serious pain not addressed,” he said. “We hope to get to the point where doctors and patients aren’t making the agonizing decision about risking side effects and addictions in order to meet patients’ needs of relief.”

Zadina’s findings, released in the journal Neuropharmacology, are particularly timely. Last year, the national Centers for Disease Control and Prevention said heroin-related deaths quadrupled nationally between 2002 and 2013.

Data from the Louisiana Department of Health and Hospitals show that from 2010 to 2013, heroin deaths in the state skyrocketed from 15 to 117, an eightfold increase. The majority of the deaths were in Orleans and Jefferson parishes, followed by East Baton Rouge.

And on Friday, Orleans Parish Coroner Dr. Jeffrey Rouse released a statement on what he termed a “public health crisis” of accidental opiate overdoses from heroin and another drug, called fentanyl.

The DEA issued a nationwide alert in early 2015 regarding the soaring use of fentanyl, describing it as 50 times more powerful than heroin.

Keith Brown, special agent in charge of the U.S. Drug Enforcement Administration’s New Orleans field office, said fentanyl is frequently used to dilute heroin before it is sold.

“Fentanyl has become a huge problem, especially in contributing to the spike in overdoses,” Brown told The New Orleans Advocate in May. “We’re seeing more and more of it in the metro area, just like we’re seeing more and more of it across the South, the mid-South and even across the country.”

The Orleans Parish Coroner’s Office recorded 44 accidental deaths due to heroin in 2014 and 43 in 2015, Rouse said.

There was only one recorded death in New Orleans from fentanyl abuse in 2014, but that number jumped to 11 in 2015.

In response to the local crisis, the New Orleans Health Department on Friday made it possible for anyone in the city to purchase naloxone, a drug commonly referred to as Narcan, over-the-counter without a separate prescription. Naloxone, which reverses the effects of an overdose, is available at the University Medical Center Outpatient Pharmacy at 2000 Canal St. EMS workers also are allowed to administer it.

Rouse said he was thankful for new laws that allow for easier access to antidotes to opiate overdoses, but he remains alarmed by the number of drug overdose deaths coming through his office.

“Fentanyl is incredibly potent,” Rouse said. “Users cannot tell if it has been used as an additive to heroin, and they can die so quickly that antidotes may be too late.”

Fentanyl comes in a legal form and is intended to manage pain. Like other opiates, though, it’s highly addictive and frequently abused.

That’s where Zadina’s new drug would help, should the U.S. Food and Drug Administration approve it.

His study started in 1997, Zadina said, when scientists isolated a neurochemical in the brain called endomorphin, which acts very specifically as morphine. In the past few years, Tulane scientists have engineered variants of the neurochemical and started testing them as alternatives to addictive drugs like Percocet, formulated about 100 years ago from the opium poppy.

In the study, which was conducted “humanely” on rats, Zadina said, the new endomorphin drug produced longer pain relief without substantially slowing the animal’s breathing. A similarly potent dosage of morphine, he said, produced “significant” respiratory depression.

Likewise, impairment of motor coordination was significant after morphine but not with the endomorphin drug.

And, significantly, the new drug produced far less tolerance than morphine, meaning higher doses are not required over time.

The rats had a chance to press a bar to self-administer both morphine and the endomorphin compound; they increased their efforts with the former, but not the latter. The test is used as a predictor of human addiction.

Zadina said human testing will likely begin in the next couple of years. If approved, the drug could hit the market between three and 10 years after that.

“You never know what might pop up to stop us,” Zadina said. “We’d like to move faster, of course.”