Teva will discontinue its Phase 2 TOPAS-MSA trial of emrusolmin after an interim futility analysis indicated a low probability of meeting the primary efficacy endpoint in multiple system atrophy.
Written By: Aasritha Thippavajjala, PharmD
Reviewed By: Pharmacally Editorial Team
Teva Pharmaceuticals announced on November 2, 2026, that it will discontinue TOPAS-MSA, its Phase 2 study evaluating investigational emrusolmin (TEV-‘286; TEV-56286) in adults with multiple system atrophy (MSA). The decision followed a recommendation from the independent Data Monitoring Committee (IDMC) after a prespecified interim futility analysis met the study’s predefined stopping criterion. The assessment indicated a low probability of achieving the primary efficacy endpoint if the trial continued. Teva clarified that this was a predictive interim assessment rather than the study’s final efficacy analysis.
TOPAS-MSA Study Design and Patient Population
TOPAS-MSA (NCT06568237; protocol TV56286-NDG-20039) was a multicentre, randomized, double-blind, placebo-controlled Phase 2 study designed to evaluate the efficacy and safety of emrusolmin in adults with MSA. The trial planned to enrol approximately 350 participants, with ClinicalTrials.gov reporting actual enrolment of 349. Participants were assigned to oral emrusolmin 300 mg or matching placebo for approximately 48 weeks, followed by a four-week follow-up period.
Emrusolmin is an investigational small molecule designed to target alpha-synuclein aggregation, a disease-associated mechanism implicated in MSA. Teva is developing the compound through its partnership with MODAG GmbH.
Interim Futility Analysis and Discontinuation Decision
The IDMC recommended discontinuing TOPAS-MSA after the prespecified interim analysis met the predefined futility criterion. According to Teva, the assessment indicated a low probability that the study would achieve its primary efficacy endpoint if continued.
The company did not disclose numerical interim efficacy estimates, treatment-group differences or statistical measures underlying the futility assessment. Consequently, the decision represents a prediction about the likelihood of achieving the primary endpoint, rather than a completed analysis demonstrating that emrusolmin lacks clinical efficacy.
Primary Efficacy Endpoint: Modified UMSARS
The primary endpoint was the change from baseline to Week 48 in the modified Unified Multiple System Atrophy Rating Scale (UMSARS) Part I score. The trial registry specifies different endpoint definitions for participants inside and outside the European Union.
For participants outside the EU, the endpoint excluded item 11 from modified UMSARS Part I, with item scoring rescaled from 0 to 3. For EU participants, the primary endpoint was the combined UMSARS Part I and Part II total score. UMSARS Part I assesses disease-related impairments through historical assessment, while Part II evaluates motor function.
No numerical primary endpoint results or treatment-versus-placebo comparisons were disclosed.
Secondary Efficacy Endpoints
Registered key secondary assessments included the complementary UMSARS measure for each geographical group, UMSARS Part I score, lateral ventricular volume measured by magnetic resonance imaging (MRI), Clinical Global Impression–Severity (CGI-S), Patient Global Impression–Severity (PGI-S), and neurofilament light chain (NfL) concentrations in cerebrospinal fluid.
Additional assessments included pons and cerebellar volumes, UMSARS Part II and Part IV scores, the two-minute walk test, and the Multiple System Atrophy Quality of Life questionnaire. These were planned assessments; Teva has not reported their interim or final results.
Safety and Tolerability
Teva reported that no safety concerns were identified in the interim analysis. Registered safety assessments included treatment-emergent adverse events, withdrawals due to adverse events, and potentially clinically significant changes in vital signs, laboratory parameters and electrocardiogram findings.
The announcement did not provide adverse-event counts, incidence rates or comparative safety results. Therefore, the interim safety statement should not be interpreted as a comprehensive assessment of emrusolmin’s safety profile.
Development Implications and Next Steps
The discontinuation represents a setback for emrusolmin’s Phase 2 efficacy evaluation in MSA. However, the futility assessment does not establish the absence of a treatment effect or provide a definitive estimate of the compound’s clinical efficacy. The lack of disclosed endpoint-level data also limits independent assessment of the interim findings.
Importantly, Teva’s decision applies specifically to TOPAS-MSA and does not represent a final decision on the broader emrusolmin development programme. The company plans a comprehensive analysis of TOPAS-MSA data alongside available findings from a separate Phase 2 open-label extension study (NCT07197866), which evaluates the long-term safety and tolerability of emrusolmin in eligible participants who completed the 48-week treatment period.
Teva plans to share the findings with the scientific community after completing its analysis and will work with investigators to ensure study protocols are followed during discontinuation. The forthcoming data evaluation may provide further insight into the compound’s development prospects, although no decision on its future clinical development has been announced.
References
Teva Pharmaceuticals. Teva to Discontinue Phase 2 TOPAS-MSA Study of emrusolmin (TEV-‘286) Following Interim Futility Analysis. November 2, 2026.
A Trial to Test if TEV-56286 is Effective for Treatment of Participants with Multiple System Atrophy (TOPAS-MSA), ClinicalTrials.gov ID NCT06568237
About the Writer
Aasritha Thippavajjala (Linkedin) is a pharm D student and aspiring medical writer with medical writing, clinical training experience and a strong interest in clinical research and patient safety She has hands-on exposure to clinical pharmacy activities including medication profile assessment, clinical case review, identification of potential drug-related problems, ADR awareness, patient counselling, and clinical documentation. She has also gained experience in medical literature review, evidence synthesis, and scientific communication through her published review article on digital twin-based patient simulation and her poster presentation at the 74th Indian Pharmaceutical Congress. Certified in ICH Good Clinical Practice (E6(R3)) and Scientific Writing in Health Research, she is passionate about applying her clinical knowledge and research skills to medical writing ,clinical research and contributing to accurate, evidence-based healthcare.