Alkermes plc (NASDAQ:ALKS) dropped topline results Monday from its Phase 1 proof-of-concept study of ALKS 7290, an investigational orexin 2 receptor agonist aimed at treating attention-deficit hyperactivity disorder in adults.

Here's the interesting part: this is the first clinical evidence that an orexin receptor agonist does anything at all for ADHD symptoms. That's a genuinely new lane, not another variation on the stimulant-and-non-stimulant carousel that's defined the space for decades.

The study looked at 88 healthy volunteers and 50 adults with ADHD, and ALKS 7290 came out generally well tolerated across every dose tested.

What the Data Actually Showed

In the Phase 1b portion, 50 adult participants went through a two-week washout of their prior medications, then received daily split doses of either 20 mg or 50 mg of ALKS 7290, or a placebo, over 14 days of inpatient treatment.

By day 14, the ALKS 7290 groups posted dose-dependent reductions from baseline on the Adult ADHD Investigator Symptom Rating Scale. Median total scores fell 14.0 points in the 20 mg group and 19.0 points in the 50 mg group. Improvements started showing up as early as day 6, across both the inattentive and hyperactivity subscales.

The drug also moved the needle on overall disease severity, measured by the Clinical Global Impression-Severity Scale. Median scores dropped 1.0 point for the 20 mg group and 2.0 points for the 50 mg group, shifting patients from markedly or moderately ill to mildly ill.

EEG-based biomarkers and cognitive assessments picked up treatment effects in working memory, attention, processing speed, and information processing.

Alkermes says ALKS 7290, an investigational oral orexin 2 receptor agonist, could offer a novel approach to ADHD by targeting a brain pathway involved in wakefulness, attention, cognition and mood. That's a different mechanism than the dopamine-and-norepinephrine levers most ADHD drugs pull.

Safety and What Comes Next

The drug kept a favorable safety profile, with no serious treatment-emergent adverse events reported. The most common adverse events were mild: insomnia, pollakiuria, dizziness, altered sustained attention, micturition urgency, and constipation.

Worth noting: nobody taking ALKS 7290 discontinued the trial. Two placebo participants dropped out instead.

Alkermes is now enrolling approximately 312 adults with ADHD for a Phase 2 study testing once-daily and split doses over four weeks. Investigators dosed the first participant in September 2026.

ALKS Price Action: Alkermes shares were up 1.27% to $43.95 at the time of publication on Monday, according to market data.