AtaiBeckley Announces Expanded Phase 2a Results For EMP-01 In Adults With Social Anxiety Disorder That Demonstrate Clinically Meaningful And Consistent Improvements Across Clinician-Rated Symptoms, Patient-Reported Experience And Real-World Behavioral Outcomes

At Day 43, EMP‑01 achieved a 38% reduction vs 15% on placebo (Hedges' g=0.84) on the patient-reported Social Phobia Inventory (SPIN), a 32% reduction vs 14% on placebo on the Subtle Avoidance Frequency Examination (SAFE), and a previously reported −11.9-point LS mean difference (LSMD) on the Liebowitz Social Anxiety Scale (LSAS) versus placebo (g=0.45), with 49% responder rates on both Clinical Global Impression-Improvement (CGI-I) (previously reported) and Patient Global Impressions of Change (PGI-C). EMP-01 was well tolerated, with no severe or serious adverse events.

Efficacy Findings

EMP‑01 produced consistent and clinically meaningful improvements across all major symptom domains of SAD:

• LSAS: EMP-01 demonstrated a clinically meaningful LSMD of −11.9‑points vs placebo (g=0.45) at Day 43 (previously reported), with both total and subscale improvements. Improvements were observed across both fear and avoidance subscales on the clinician-rated 24-item Liebowitz Social Anxiety Scale, indicating that patients experienced fewer social situations as distressing and were more able to engage in them. This degree of change is considered clinically meaningful and reflects broad symptom improvement across core features of social anxiety disorder including fear and anxiety of social situations.
• SPIN: EMP-01 produced a large, clinically meaningful patient-reported improvement of -18.3-points (38% reduction vs 15% on placebo), which corresponded to a large between-group standardized effect size (g=0.84), in self-reported SAD symptoms from baseline to Day 43. Additional model-based analyses further supported treatment benefits at Day 43, showing statistically significant improvements with a placebo-adjusted LSMD of -11.5 points (95% CI: -18.5, -4.6; p=0.002) at Day 43. Patients treated with EMP-01 moved from severe baseline symptom severity to substantially lower symptom burden by Day 43. These results on the 17-item SPIN are equivalent to being able to initiate conversations, attend social events, and perform at work with substantially less fear and avoidance.
• SAFE: EMP-01 demonstrated a large, clinically meaningful improvement of −25.9‑points (32% reduction vs 14% on placebo) in real-world behavioral avoidance at Day 43. Additional model-based analyses further supported treatment benefits at Day 43, showing statistically significant improvements with a placebo-adjusted LSMD of -15.6 points at Day 43 (95% CI: -26.0, -5.2; p=0.004). These results on the Subtle Avoidance Frequency Examination, a 32-item questionnaire that measures safety behaviors, suggest that participants were more willing to participate in everyday activities such as social interactions without engaging in avoidant coping behaviors.
• Clinical impression: 49% CGI‑I responders (NNT=2.95) at Day 43 compared to 15% on placebo (previously reported). This measure reflects clinicians' overall judgment of meaningful improvement in a patient's condition, considering symptom severity, functioning, and overall clinical presentation.
• Patient perception: 49% PGI‑C responders (NNT=2.72) at Day 43 compared to 12% on placebo. This result indicates that patients themselves perceived the treatment‑associated improvements as noticeable and meaningful in their daily lives, reinforcing the clinical and functional outcomes observed on other measures.
  Safety & Tolerability
  
  EMP‑01 was generally safe and well tolerated:
• No SAEs and no severe TEAEs in any participant
• 97% retention, with 0% study dropouts attributed to TEAEs
• TEAEs were expected and consistent with the class, transient, and predominantly mild‑to‑moderate
  
  
  
  Professor Murray Stein, Distinguished Professor of Psychiatry and Public Health at the University of California San Diego (UCSD) and consultant to AtaiBeckley, said: "I was particularly struck by the consistency of the findings across clinician-rated and patient-reported outcomes. The improvement on the SAFE is especially interesting because reductions in subtle avoidance behaviors are seen as an important goal of cognitive behavioral therapies and yet are seldom measured in medication trials for social anxiety disorder. Taken together, these findings provide strong support for continued development of EMP-01."

Management Commentary

Dr Srinivas Rao, Co-Founder and Chief Executive Officer at AtaiBeckley, said: "In this Phase 2a trial of 70 patients, EMP-01 delivered a 49% clinician-rated and patient-reported responder rate alongside significant improvements across LSAS, SPIN, and real-world avoidance behavior. Unlike current standards of care, which require daily, chronic dosing, the durability observed in this study following just two administrations suggests that EMP-01 could be a differentiated treatment option that could meaningfully improve outcomes for people living with Social Anxiety Disorder."

Dr Kevin Craig, Chief Medical Officer at AtaiBeckley said: "Social Anxiety Disorder is a chronic and highly impairing condition for which many patients do not achieve adequate benefit from currently available treatments. The consistent improvements observed across clinician-rated symptoms, patient-reported experience, and avoidance behavior—alongside a favorable tolerability profile—provide encouraging evidence that EMP-01 may address multiple important dimensions of this disorder."

Study Design

The multi-center study enrolled 71 adults with moderate-to-severe SAD across 7 clinical sites in the UK. Participants were randomized to receive two in-clinic administrations of EMP-01 (225 mg) or placebo, given 28 days apart, with no adjunctive psychotherapy. 70 participants received at least one dose of study drug, and 69 completed the Day 43 efficacy assessments, indicating high patient acceptability and retention. All clinician-rated assessments were conducted by blinded central raters. Topline results from this study were previously reported in February 2026.