Decision brief · what the records say, not our assessment
A Study of CPX-351 (Vyxeos™) With Quizartinib for the Treatment of FLT3-ITD Mutation-Positive Acute Myeloid Leukemia
NCT04209725 · SCRI Development Innovations, LLC · PHASE2 · terminated · Open Targets disease: leukemia, acute myeloid, susceptibility to · Why it stopped
Six questions a reader deciding whether to spend more time on this asks, each answered with flags: yes, no, or not published (hatched), each with its rule and source record. Flags are never added up into a score or a verdict, because published success rates disagree by a factor of two and more.
1. Is the biology right?
- Somatic driver evidence: no · None of POLA1, POLD4, POLD3, CSF1R, FLT3, KIT has somatic-mutation evidence in leukemia, acute myeloid, susceptibility toRule: Open Targets has somatic-mutation evidence for the target in this cancer. Source: Open Targets: POLA1 in leukemia, acute myeloid, susceptibility to, 2026-11-11
- Human genetic evidence: yes · FLT3: curated genetic literatureRule: Any germline or somatic human genetic evidence for the target in this cancer, counted apart from animal-model and literature evidence. Source: Open Targets: FLT3 in leukemia, acute myeloid, susceptibility to, 2026-11-11Published context: 2.6× relative probability of success, phase 1 to launch, with human genetic support (Minikel et al., Nature 2024, drug programs to 2023). All therapy areas, mostly germline evidence; not a probability for this program.
- Pediatric target: yes · CSF1R, FLT3, KIT on the FDA listRule: Target is on FDA's Pediatric Molecular Target List (relevant targets); membership alone neither requires nor waives a study. Source: FDA Pediatric Molecular Target List (Listed as February 2026 on the FDA Pediatric Oncology page; the file served is 9.7.22_the_relevant_molecular_target_list.xlsx, whose Summary of Changes sheet is headed 'SEPTEMBER 2022 UPDATE' (footnote date 2022-09-01)), 2026-11-11
- Haematologic cancer: yes · HaematologicRule: From the indication, or the registry conditions when no indication matches. Source: ClinicalTrials.gov NCT04209725, 2026-11-11Published context: Likelihood of approval from phase 1: 7.5% haematologic vs 4.6% solid (BIO / Informa / QLS 2021, 2011–2020). Population-level, not a prediction.
- POLA1 (via CPX-351): Open Targets has no association between POLA1 and leukemia, acute myeloid, susceptibility to. · Open Targets: POLA1 in leukemia, acute myeloid, susceptibility to
- POLD4 (via CPX-351): Open Targets has no association between POLD4 and leukemia, acute myeloid, susceptibility to. · Open Targets: POLD4 in leukemia, acute myeloid, susceptibility to
- POLD3 (via CPX-351): Open Targets has no association between POLD3 and leukemia, acute myeloid, susceptibility to. · Open Targets: POLD3 in leukemia, acute myeloid, susceptibility to
- CSF1R (via Quizartinib): Open Targets has no association between CSF1R and leukemia, acute myeloid, susceptibility to. · Open Targets: CSF1R in leukemia, acute myeloid, susceptibility to
- FLT3 (via Quizartinib): Evidence types in leukemia, acute myeloid, susceptibility to: genetic_literature. Datasources: clingen. · Open Targets: FLT3 in leukemia, acute myeloid, susceptibility to
- KIT (via Quizartinib): Open Targets has no association between KIT and leukemia, acute myeloid, susceptibility to. · Open Targets: KIT in leukemia, acute myeloid, susceptibility to
- Not loaded on this app yet: Normal-tissue expression in vital organs. Source: Human Protein Atlas (ticket 36).
- Not loaded on this app yet: Pan-essential in cell lines. Source: DepMap (ticket 36).
- Not loaded on this app yet: Approved drug on this target. Source: Drugs@FDA (ticket 30).
2. Can the result be trusted?
- Randomised: no · Single groupRule: Registry allocation field. Source: ClinicalTrials.gov NCT04209725, 2026-11-11
- Small denominator: yes · 1 enrolled; each patient moves a rate by 100 ÷ 1 = 100.0 pointsRule: Enrolment under 30; the arithmetic is shown, not a benchmark. Source: ClinicalTrials.gov NCT04209725, 2026-11-11
- Primary endpoint is overall survival: no · Number of Patients With Treatment Related Adverse Events After Taking CPX-351 and Quizartinib; Number of Patients With an Overall Response Taking CPX-351 and QuizartinibRule: A registered primary outcome measure names overall survival. Source: ClinicalTrials.gov NCT04209725, 2026-11-11Published context: Non-OS primary endpoint: odds ratio 2.79 for a positive phase 3 (Otsuka 2021, 400 phase 3 oncology trials, to 2020). Shown with the next figure: a surrogate is easier to hit, and often a weak guide to survival.Published context: 52% of surrogate-to-OS correlations are low (Prasad 2015, published to 2014). Shown with the figure above.
- Results overdue: no · Results posted 2022-06-03Rule: Primary completion (actual) more than 12 months ago and no results posted to the registry. Source: ClinicalTrials.gov NCT04209725, 2026-11-11
- Not loaded on this app yet: Treated and evaluable counts, assessor, confirmed response, follow-up and data cutoff. Source: Readout extraction (ticket 32).
- Not loaded on this app yet: Primary endpoint changed between registry versions. Source: Registry versions in the store (ticket 32).
3. What must it beat?
- Not loaded on this app yet: Control-arm result and approved therapies for the same segment, with label links. Source: Drugs@FDA, FDA labels and readouts (tickets 30, 32).
4. Too crowded, or too late?
- Stopped on this target: 1086 terminated, withdrawn or suspended trials of drugs against POLA1; 6 of the 200 most recent give no reason. Reasons are quoted as the registry gives them on the target page. · POLA1: what already stopped
- Not loaded on this app yet: Programs on the target by phase and months behind the leader. Source: Programs and Drugs@FDA (ticket 33).
5. Can it be approved, and stay approved?
- Single-country: yes · All 5 sites in United StatesRule: All listed sites are in one country; the share of US sites is shown. Source: ClinicalTrials.gov NCT04209725, 2026-11-11
- EU paediatric investigation plan: yes · EMEA-001821-PIP01-15-M08 (quizartinib, Treatment of acute myeloid leukaemia): PM: decision on the application for modification of an agreed PIP, 14 Jun 2024Rule: An EMA PIP decision (agreement, modification or waiver) lists the drug as its active substance, exact name. Source: EMA EMEA-001821-PIP01-15-M08, 2026-11-11
- EU orphan designation: no · No EU orphan designation names CPX-351, QuizartinibRule: An EU orphan designation lists the drug as its active substance (exact name) or belongs to a medicine that does; withdrawn and expired designations are listed with their status. Source: EMA data download (dated snapshot), 2026-11-11
- Authorised in the EU: yes · Vanflyta: authorised since 6 Nov 2023; Vanflyta: refusedRule: An EMA medicine record lists the drug as its active substance or INN, exact name; national-only authorisations are not in this file. Source: EMA data download (dated snapshot), 2026-11-11
- FDA orphan designation: not published · FDA's orphan designation database turns away automated requests, so this app does not read it; search it by hand at the linkRule: Would be: an FDA orphan designation names the drug. Source: FDA orphan designations search
- FDA pediatric oncology approval: no · FDA's table lists no pediatric approval of CPX-351, QuizartinibRule: FDA's Pediatric Oncology Drug Approvals table names the drug. Source: FDA Pediatric Oncology Drug Approvals (content current as of 2026-03-03), 2026-11-11
- Registered studies open to children: yes · 12 interventional studies of CPX-351, Quizartinib include patients under 18; 6 are recruiting, not yet recruiting or activeRule: The registry's age group includes Child (birth to 17 years), which also counts studies that set no minimum age. Source: ClinicalTrials.gov search, 2026-11-11
- Caveat: Site counts are not patients per country, and trials registered only outside ClinicalTrials.gov are not covered. Where the sites are is a fact about the record, not a judgement of its quality.
- Rare pediatric disease voucher: FDA, content current as of 29 Apr 2026: “As of February 3, 2026, enactment of the Consolidated Appropriations Act, 2026, the rare pediatric disease PRV program will sunset after September 30, 2029. FDA may not award any PRVs under this program after September 30, 2029.” Voucher sale prices are not shown here; they appear only as company-reported news. · FDA: Rare Pediatric Disease Designation and Priority Review Voucher Programs
- Not loaded on this app yet: Precedent approvals for target, modality and endpoint; accelerated-approval status. Source: Drugs@FDA and FDA accelerated-approval tables (ticket 30).
6. Can the sponsor finish?
- Sponsor: SCRI Development Innovations, LLC (academic or other) · ClinicalTrials.gov NCT04209725
- study chair: Michael Tees, MD, MPH, Colorado Blood Cancer Institute · Person page
- Not loaded on this app yet: Filed cash, quarterly spend and the runway arithmetic. Source: SEC XBRL company facts (ticket 37).
- Not loaded on this app yet: Sponsor's completed vs stopped oncology trials and results-reporting record. Source: Registry, by company (ticket 37).
What public data cannot tell you
Public records cannot show: sales forecasts; a probability of success for this asset; full deal terms and net prices; FDA designations and action dates before approval (shown only as company-reported); clinical holds unless the company disclosed them; manufacturing; patents on unapproved drugs; whether preclinical findings have been replicated.
Sources: ClinicalTrials.gov NCT04209725 (2026-11-11); Open Targets Platform (2026-11-11); FDA Pediatric Molecular Target List (Listed as February 2026 on the FDA Pediatric Oncology page; the file served is 9.7.22_the_relevant_molecular_target_list.xlsx, whose Summary of Changes sheet is headed 'SEPTEMBER 2022 UPDATE' (footnote date 2022-09-01)) (2026-11-11). JSON: /api/brief/trial/NCT04209725. Not medical advice.