Stop-reason hub

SAFETY clinical trial stops

Search 717 stopped clinical trials classified as safety, with source-linked records and failure-signal context.

This page groups real ClinicalTrials.gov-derived stopped trial records. The strongest added signal is the stop-reason classification: 717 of these records are likely biological failure signals, while the rest may reflect operational, strategic, regulatory, funding, enrollment, or unclear stop reasons.

Total stopped trials717
Likely biological signals717
Shown below100

Dominant stop reasons

SAFETY
717

Notable sponsors

Pfizer
23
GlaxoSmithKline
18
Novartis Pharmaceuticals
12
Biogen
9
Gilead Sciences
9

Related phases

Phase II
276
Phase I
257
Phase III
124
Phase IV
33
Unknown
21

Crawlable stopped-trial records

Open Explore

Showing up to 100 representative records from this slice. Each link opens the trial detail page with source attribution and stop-reason context.

NCT06351332: ZAP-IT: ZN-c3 + Carboplatin + Pembrolizumab in mTNBC

Phase I Breast Cancer trial by Filipa Lynce, MD. Stop reason: SAFETY.

Zentalis terminated contract due to concern for toxicity safety from previously reported serious adverse events. This study had been designed as a Phase I / Phase II study, but never reached Phase II.

NCT03290092: Trial of Taselisib in Overgrowth

Phase I PIK3CA-Related Overgrowth trial by Centre Hospitalier Universitaire Dijon. Stop reason: SAFETY.

In accordance with the protocol, following the occurrence of two SUSARs, the TOTEM trial was stopped early for safety reasons.

NCT05583110: Efficacy and Safety of the Combination of Trastuzumab Plus TUCAtinib Plus viNorelbine in Patients With HER2-positive Non-resectable Locally Advanced or Metastatic Breast Cancer

Phase II HER2-positive Metastatic Breast Cancer trial by Spanish Breast Cancer Research Group. Stop reason: SAFETY.

The study was closed early due to safety concerns and an unfavorable benefit-risk balance. Unexpected high neutropenia rates required a costly sub-study, which was not feasible, forcing the sponsor to terminate the trial prematurely.

NCT04188509: Open-Label Extension of Voxelotor

Phase III Sickle Cell Disease trial by Pfizer. Stop reason: SAFETY.

Emerging clinical data evaluated by Pfizer and shared with regulatory authorities indicates that the risk profile of voxelotor in people with SCD exceeds the benefits observed in previously generated global research and requires further assessment.

NCT05429502: Study of Efficacy and Safety of Ribociclib (LEE011) in Combination With Topotecan and Temozolomide (TOTEM) in Pediatric Patients With Relapsed or Refractory Neuroblastoma and Other Solid Tumors

Phase I Neuroblastoma trial by Novartis Pharmaceuticals. Stop reason: SAFETY.

Study halted early due to high toxicity risk (from BHLRM model) in combo treatment and inability to identify recommended Phase 2 dose in initial phase (Phase 1-Part A), making continuation to subsequent phases (Phase 1-Part B and Phase 2) unfeasible.

NCT04239092: 9-ING-41 in Pediatric Patients With Refractory Malignancies.

Phase I Refractory Cancer trial by Actuate Therapeutics Inc.. Stop reason: SAFETY.

The decision to conclude study was made to optimize the clinical study design and protocol to further evaluate the safety profile of elraglusib (9-ING-41) in pediatric and adult patients with refractory Ewings Sarcoma.

NCT05561140: Resolution of Sickle Cell Leg Ulcers With Voxelotor

Phase III Sickle Cell Disease trial by Pfizer. Stop reason: SAFETY.

Emerging clinical data evaluated by Pfizer and shared with regulatory authorities indicates that the risk profile of voxelotor in people with SCD exceeds the benefits observed in previously generated global research and requires further assessment.