Takeda and Alkermes Unveil Promising Data for Narcolepsy Treatments at World Sleep 2025

In a significant development for narcolepsy treatment, pharmaceutical giants Takeda and Alkermes have presented compelling data for their respective orexin receptor 2 (OX2R)-selective agonists at the World Sleep 2025 Congress in Singapore. These revelations mark a crucial step forward in the race to bring a new class of narcolepsy drugs to market, potentially transforming care for patients suffering from this chronic sleep disorder.

Takeda's Oveporexton Demonstrates Strong Efficacy in Phase 3 Trials

Takeda's candidate, oveporexton, has shown impressive results in its FirstLight and RadiantLight phase 3 trials, involving over 270 patients across 19 countries. The drug, which mimics the body's natural orexin cycle, demonstrated statistically significant improvements in excessive daytime sleepiness as measured by the Maintenance of Wakefulness Test (MWT).

Key findings from Takeda's presentation include:

• The majority of patients treated with the twice-daily 2-mg dose achieved wakefulness within the "normative range" on the MWT.
• Nearly 85% of patients on this dosing regimen achieved sleepiness scores comparable to healthy individuals.
• Median cataplexy-free days increased from zero at baseline to 4-5 days per week by Week 12.
• The mean narcolepsy severity score dropped from 30-31 at baseline to around 10 by Week 12.
• 97% of patients reported improvements on a self-rated symptoms scale.

Sarah Sheikh, head of Takeda's neuroscience therapeutic area unit, emphasized the transformative potential of these results, stating they "demonstrate the potential for a new era of care defined by multiple treatment measures that matter to patients."

Alkermes' Alixorexton Shows Promise with Once-Daily Dosing

Not to be outdone, Alkermes presented phase 2 data for its contender, alixorexton, highlighting its efficacy with once-daily dosing. The company claims alixorexton is the "first OX2R agonist to demonstrate clinically meaningful and statistically significant impact on wakefulness, cognition and fatigue with once-daily dosing."

Alkermes' data revealed:

• All alixorexton dose groups achieved "normative wakefulness" on the MWT, with mean sleep latency ranging from 24 to 28 minutes across different doses.
• More than 40% of patients in the 6-mg and 8-mg cohorts experienced complete cataplexy elimination by Week 6.
• The safety profile was similar to oveporexton, with no serious treatment-emergent adverse events (TEAEs) reported.

Alkermes CEO Richard Pops emphasized the significance of these results, stating they "represent a significant new contribution to the evidence base supporting the utility of orexin 2 receptor agonists in central disorders of hypersomnolence."

Market Implications and Future Outlook

While Takeda appears to be leading the race with plans to file for FDA approval this fiscal year, industry analysts suggest the competition remains open. Leerink analysts noted that despite oveporexton's "significant first-mover advantage," it could face challenges from once-daily dosing options like Alkermes' alixorexton and Centessa Pharmaceuticals' ORX750.

Takeda is targeting $2 billion to $3 billion in peak revenue potential for oveporexton as a treatment for narcolepsy type 1 (NT1), with initial focus on the U.S. market. Meanwhile, Alkermes is set to advance alixorexton into phase 3 trials in the first quarter of 2026.

As the pharmaceutical industry eagerly awaits further developments, these advancements in narcolepsy treatment promise to offer new hope for patients and potentially reshape the landscape of sleep disorder therapeutics.