Orexo submits New Drug Application to FDA for OX124, a high-dose rescue medication for opioid overdose

• OX124 is designed to reverse the effects of the most powerful synthetic opioids, such as fentanyl
• Nine out of ten fatal opioid overdoses in the US involve synthetic opioids
• If approved, the US launch is expected to be initiated in H1 2024

UPPSALA, Sweden, Feb. 3, 2023 /PRNewswire/ -- Orexo AB (publ.), (STO: ORX) (OTCQX: ORXOY), today announces the submission of a New Drug Application (NDA) to the US Food and Drug Administration (FDA) for its lead pharmaceutical pipeline asset, OX124, a nasal rescue medication for opioid overdose. OX124, is based on Orexo´s drug delivery platform amorphOX® and contains a high-dose of naloxone.

The submission is supported by data from the pivotal study in healthy volunteers, OX124-002, where OX124 showed a significantly faster and higher absorption of naloxone compared to intramuscular dosing with an injection reference product. In addition, development formulations of OX124 have in a previous exploratory clinical study (OX124-001) in healthy volunteers, demonstrated a more rapid absorption and higher bioavailability compared with the market leading naloxone rescue medication, even with the same dose as the comparator. OX124 is protected by patents until 2039.

Opioid overdose is a life-threatening condition, characterized by loss of consciousness and respiratory depression. Opioid overdoses can be treated with the opioid antagonist naloxone. During the 12-month period ending August 2022, the predicted annual number of fatal opioid overdoses in the US exceeded 81,000¹. Nine out of ten opioid overdose deaths involved synthetic opioids, including fentanyl. The switch to highly potent synthetic opioids has led to more severe overdoses, prompting the need for high-dose naloxone products.

Nikolaj Sørensen, President and CEO of Orexo AB, said: "With the filing of OX124 we are now one step closer to bringing this important product to market, providing this life-saving medication to the stigmatized and underserved patient group with opioid use disorder. From a business perspective this medication is a great strategic fit, further expanding our portfolio for patients with opioid use disorder, complementing ZUBSOLV® and MODIA®."  

The market today is solely based on prescription products but is likely to convert into a low-dose over the counter (OTC) market and a high-dose prescription market, including OX124. The increased availability of naloxone products is expected to grow the market from today's USD 300-500 million. OX124 will, as a high-dose prescription product, have access to reimburse-ment and act in a differentiated market to the OTC market, which is likely to include the current market leader and generics thereof. The large need for potent and longer-lasting overdose rescue medications will most likely propel the prescription market. In addition, the on-going expansion of mandatory co-prescription of naloxone rescue medication will much likely also benefit the market for prescription products.

FDA´s ordinary review process is 10 months, but recent review processes in the category have been about 13 months. Orexo is planning to initiate the US launch during H1 2024.

For further information please contact:

Orexo AB (publ.)

About OX124-002 

This pivotal trial was a 4-period cross-over, comparative bioavailability study in healthy volunteers, comparing two dose regimens of OX124 to two dose regimens of an injection reference product. The study met its primary endpoints with naloxone exposure within the targeted interval. In addition, it showed a significantly faster and higher absorption of naloxone compared to intramuscular dosing with the injection reference product. OX124 was also well tolerated.

About OX124-001 

This study was a cross-over, comparative, bioavailability study comparing four development formulations of OX124 to the market leading naloxone rescue medication (4 mg) in the US. All formulations of OX124 were well tolerated and showed substantially higher plasma concentrations of naloxone, sustained duration of elevated plasma concentrations, and equivalent or superior onset time versus the comparator.

About Orexo

Orexo develops improved pharmaceuticals and digital therapies addressing unmet needs within the growing space of substance use disorders and mental health. The products are commercialized by Orexo in the US or via partners worldwide. The main market today is the American market for buprenorphine/naloxone products, where Orexo commercializes its lead product ZUBSOLV® for treatment of opioid use disorder. Total net sales for 2022 amounted to SEK 624 million and the number of employees was 126. Orexo is listed on the Nasdaq Stockholm Main Market (ORX) and is available as ADRs on OTCQX (ORXOY) in the US. The company is headquartered in Uppsala, Sweden, where research and development activities are performed.

For more information about Orexo please visit www.orexo.com. You can also follow Orexo on Twitter, @orexoabpubl, LinkedIn, and YouTube.

The information was submitted for publication at 8.00 CET on February 3, 2023. 

¹ https://www.cdc.gov/nchs/nvss/vsrr/drug-overdose-data.htm.

During the same period the predicted annual number of total fatal overdoses amounted to more than 107,000.

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