Neuren Pharmaceuticals Advances First-Ever Phase 3 Trial for Phelan-McDermid Syndrome with Promising Phase 2 Results
核心洞察
Neuren Pharmaceuticals has dosed the first patient in its landmark Koala Phase 3 trial of NNZ-2591 for Phelan-McDermid syndrome (搜索), marking the first-ever Phase 3 study for this rare neurodevelopmental disorder.
Published Phase 2 data showed statistically significant improvements across 10 of 14 efficacy assessments, including communication, behavior, and quality of life measures in 18 children with PMS.
The Phase 3 trial has received regulatory approval from both the FDA and Health Canada, with plans to enroll approximately 160 children aged 3-12 years across multiple sites.
Neuren Pharmaceuticals has achieved a significant milestone in rare disease drug development by dosing the first participant in its Koala Phase 3 trial of NNZ-2591 for Phelan-McDermid syndrome (搜索) (PMS). This marks the first-ever Phase 3 study conducted for this rare neurodevelopmental disorder, which currently lacks any approved treatments.
The randomized, double-blind, placebo-controlled trial plans to enroll approximately 160 children aged between 3 and 12 years old. The trial protocol includes a four-week screening period, followed by a 13-week period of twice-daily dosing. Neuren anticipates activating two additional sites this month, with a further 20 sites progressing towards activation across the United States.
Regulatory Approvals Expand Global Reach
Health Canada has approved Neuren's Clinical Trial Application for the Koala Phase 3 trial, clearing the way for the inclusion of clinical trial sites in Canada and further expanding the global reach of the study. The trial had previously received Investigational New Drug approval from the US Food and Drug Administration, enabling enrollment at US sites to commence. The second clinical site in California is now activated and actively enrolling participants.
"Regulatory clearance from a second authority underscores the significance of the Koala trial and reinforces the company's commitment to advancing NNZ-2591 as a potential therapy for children with this severe condition," said Jon Pilcher, Neuren's Chief Executive Officer.
Strong Phase 2 Results Support Advancement
The Phase 3 trial builds on encouraging Phase 2 data recently published for NNZ-2591, a synthetic analog of the insulin-like growth factor 1 (IGF-1 (搜索)) metabolite cyclic glycine-proline. The Phase 2 open-label trial featured 18 patients aged 3-12 (mean age, 8.6 years) with PMS who received twice-daily oral NNZ-2591 for 13 weeks.
Led by Elizabeth Berry-Kravis, MD, PhD, professor of Pediatrics and Neurological Sciences and director of the RUSH Pediatric Neurosciences F.A.S.T. Center for Translational Research at Rush University Medical Center in Chicago, the study showed statistically significant improvements in 10 of the 14 efficacy assessments covering clinically important aspects of PMS.
Comprehensive Efficacy Across Multiple Domains
The Phase 2 results demonstrated meaningful improvements across several key areas. Communication outcomes showed significant gains in VABS-3 receptive communication (raw score change from baseline: mean, 7.5; P = 0.0001) and expressive communication (raw score change: mean, 3.3; P = 0.0298).
Statistically significant improvements were also observed in Clinical Global Impression-Improvement (week 13 mean, 2.4; P <.0001), Caregiver Impression of Change (mean, 2.7; P = .0003), and Quality of Life Inventory-Disability overall score (week 13 mean, 70.9; P = .0066). Additional improvements were seen in behavior measures, including the Aberrant Behavior Checklist (week 13 mean, 53.2; P = .0013) and sleep patterns via the Child Sleep Habits Questionnaire (week 13 mean, 42.5; P = .0191).
Safety Profile and Regulatory Support
The safety profile of NNZ-2591 was favorable in the Phase 2 trial. Treatment-emergent adverse events (TEAEs) were reported in 17 of the 18 participants, although most TEAEs were mild to moderate in severity. The most common TEAE was psychomotor hyperactivity (n = 4), while COVID-19, decreased appetite, pyrexia, and somnolence were each reported in 3 participants. There were no clinically significant changes in laboratory values, electrocardiograms, or other safety parameters, and no deaths reported.
The program has been granted Fast Track, Rare Pediatric Disease, and Orphan Drug designations by the US Food and Drug Administration. These designations highlight the urgent need for effective treatments for PMS and provide Neuren with certain benefits to expedite the development and review process.
Addressing Critical Unmet Need
Most patients in the Phase 2 study had moderate-to-marked impairment based on Clinical Global Impression-Severity scores (mean, 4.5) at baseline. The cohort included those who had a clinical PMS diagnosis and a disease-causing genetic abnormality of the SHANK3 (搜索) gene.
NNZ-2591 represents Neuren's second major development program and has already demonstrated encouraging results in Phase 2 trials across multiple neurodevelopmental disorders, including Phelan-McDermid syndrome (搜索), Pitt Hopkins syndrome (搜索) and Angelman syndrome (搜索).
The ongoing Phase 3 study was planned in coordination with the FDA after a Type C Meeting occurred in early 2025. The study will use change in the Receptive Communication subdomain of the VABS-3 and the overall score in PMS Assessment of Change as primary endpoints, pairing the caregiver's assessment of change in one crucial symptom area with the clinician's assessment of change across multiple aspects of PMS.