Topline Results for Intranasal Med to Treat Opioid Overdose

Topline results show positive results for the experimental intranasal nalmefene product OX125 (Orexo) for opioid overdose reversal, the manufacturer announced earlier today.

A crossover, comparative bioavailability study was conducted in healthy volunteers to assess nalmefene absorption of three development formulations of OX125. Preliminary results showed “extensive and rapid absorption” across all three formulations versus an intramuscular injection of nalmefene, Orexo reported.

“As the US heroin crisis has developed to a fentanyl crisis, the medical need for novel and more powerful opioid rescue medications is vast,” Nikolaj Sørensen, president and CEO of Orexo, said in a press release.

“The need has also escalated due to the COVID-19 pandemic as the consequences of social distancing and economic weakness are expected to lead to a significant increase in mental health issues and substance use disorders,” Sørensen added.

Robert Rönn, vice president and head of R&D at Orexo, noted in the same release that the company will now be working with the US Food and Drug Administration “to identify the optimal route to market.”

Opioid Antagonist

There were more than 31,000 fatalities from highly potent synthetic opioids in the United States in 2018, the manufacturer reports.

“Like naloxone, nalmefene is an opioid antagonist that acts by blocking the effects of opioids at the opioid receptors,” it notes.

However, nalmefene has a longer half-life than naloxone. These longer-acting properties may be “of particular value to protect against renarcotization (second overdose), as the antagonist wears off,” according to an Orexo press release.

OX125 was developed to provide absorption of drug substances through the nasal mucosa.

In addition to showing rapid absorption across all formulations studied, study results showed “good tolerability, supporting the viability” of the treatment as an opioid overdose rescue medication, the company said.

“This is not only a proof-of-concept for our wholly owned OX125 product, but also a demonstration of the value of our novel nasal technology platform,” Rönn said.

“Alongside OX124, our naloxone rescue project, OX125 will be an important lifesaving addition in our commitment to helping patients suffering from opioid addiction in all phases,” Sørensen added.

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