Landscape of OXR2 targeting drugs attacking narcolepsy

Yesterday, Takeda announced it's oral OXR2 agonist cleared two Phase 3 studies in narcolepsy, opening up a >$3B peak sales opportunity

I asked Sleuth to pull together a competitive landscape and flag why analysts believe this is a huge market

Some takeaways:

Narcolepsy is a neurological sleep disorder affecting 150-300K Americans, but only ~40% are diagnosed and <40% of those get branded therapy. The underlying issue in Type 1 (T1): orexin neuron loss. The market opportunity for new treatments is massive.

The current standard of care manages symptoms, not the underlying cause. Sodium oxybates and stimulants deliver modest 15-18 min improvements on the key Maintenance of Wakefulness Test (MWT) endpoint and with significant side effects.

These drugs don't address the underlying orexin deficiency at the root of NT1, but OX2R agonists could - underpinning the excitement for overporexton and other assets in this class. The current generation of drugs targets OX2R selectively, rather than OX1R AND OX2R as earlier programs did, as recent evidence has shown narcoleptic effects are mediated by OX2R alone, but not OX1R alone.

OX2R data has been game changing:

• MWT improvements of 25-35 minutes, nearly maxing out the 40-min scale and significantly higher than the 15-18 minutes observed with oxybates
• Next gen treatments have a clean safety profile vs. earlier programs (hepatotoxicity, CV effects and visual disturbance issues) with the conversation now shifting towards tolerability
• Potential for a much more simplified polypharmacy regimen for patients - just oxybates (for nighttime sleep issues) and orexin agonists (once daily)

Looking ahead, the next major catalysts will be:

• ALK-2680 Ph2 NT1 data in Q3'25, which will be closely compared to Takeda's overporexton
• ALK-2680 Ph2 NT2 data in the fall 2025
• ORX750 Ph2 NT1 / NT2 / IH data in late 2025

By the end of the year, we should have a good sense of how this landscape will shake out, but regardless, Takeda should be the first to market, and with a follow-up asset in TAK-360 (Ph2), looks to be in a great position to break open this market.