By Pat Anson, PNN Editor

Researchers at Louisiana State University have created a new type of analgesic that is similar to acetaminophen but can relieve pain and reduce fever without the risk of liver or kidney damage.

Acetaminophen -- also known as paracetamol – is the world’s most widely used over-the-counter pain reliever. Over 50 million Americans take acetaminophen each week, many unaware that excessive use can cause liver, kidney, heart and blood pressure problems. Acetaminophen overdoses are involved in about 500 deaths and over 50,000 emergency room visits in the U.S. annually.

Researchers at LSU Health New Orleans created 21 chemical compounds that are structurally similar to acetaminophen, but did not cause liver or kidney toxicity in tests on laboratory rodents. Their findings are published online in the European Journal of Medicinal Chemistry.

"The new chemical entities reduced pain in two in models without the liver and kidney toxicity associated with current over-the-counter analgesics that are commonly used to treat pain -- acetaminophen and NSAIDs. They also reduced fever in a pyretic model,” said senior author Nicolas Bazan, MD, Director of the LSU Health New Orleans Neuroscience Center of Excellence.   

The intellectual property behind the acetaminophen analogs has been licensed to South Rampart Pharma. The company expects to file an investigational new drug application with the Food and Drug Administration in the third quarter 2020, which would pave the way for clinical studies.

"Our primary goal is to develop and commercialize new alternative pain medications that lack abuse potential and have fewer associated safety concerns than current treatment options,” said Bazan. "Given the widespread use of acetaminophen, the risk of hepatotoxicity with overuse, and the ongoing opioid epidemic, these new chemical entities represent novel, non-narcotic analgesics that exclude hepatotoxicity, for which development may lead to safer treatment of acute and chronic pain and fever.”

Bazan said the development of safer pain relievers and fever reducers is particularly important because of the COVID-19 pandemic. Current treatments have led to kidney and liver disease in critically ill SARS-CoV-2 patients.

Acetaminophen is a key ingredient in hundreds of over-the-counter pain relievers and cough, cold and flu medicines – from Excedrin and Tylenol to Theraflu and Alka-Seltzer Plus. It’s also used in opioid pain medications such as Vicodin. Nearly two-thirds of the world’s supply of acetaminophen comes from China.