ABL001-P1bC phase 1b/2 study of CTX-009 with irinotecan or paclitaxel
29 evidence topics · 4 sources
Objective
Origin of the biliary tract cancer cohort
Location and study date
Study dates and status: registry record
| Milestone | Registry record |
|---|---|
| Study start (actual) | “2020-06-22” |
| Primary completion (actual) | “2024-01-08” |
| Study completion (actual) | “2025-01-09” |
| Enrollment (actual) | “41” |
| Recruitment status | “Terminated” |
| Reason stopped | “Change of Development Plan” |
Data cut-off and follow-up of the reported phase 2 analysis
Study design
Registered design details
| Design feature | Registry record |
|---|---|
| Primary purpose | “Treatment” |
| Allocation | “Non-Randomized” |
| Interventional model | “Parallel Assignment” |
| Masking | “None (Open Label)” |
Phase 1b and phase 2 populations
Single-arm phase 2 design as reported at the congress
Simon two-stage adaptive design and the decision not to run the second stage
Eligibility criteria
Key inclusion criteria: registry record
Key exclusion criteria: registry record
Treatment
Registered interventions
| Intervention | Registry description |
|---|---|
| CTX-009 (ABL001) | “CTX-009 (ABL001) will be administered biweekly.” |
| Paclitaxel | “Paclitaxel will be administered weekly.” |
| Irinotecan | “Irinotecan will be administered biweekly.” |
Study outcomes
Rationale for using objective response rate as the primary endpoint
Registered primary outcome measures
Primary and secondary objectives as reported at the congress
Statistical analysis description
Number of participants (Planned and analyzed)
Total enrollment across both phases
Participants analyzed in the phase 2 biliary tract cancer cohort
Participants analyzed in the phase 1b cholangiocarcinoma subset
Description of analysis sets
Basis of the reported response assessment
Formal definition of the efficacy and safety analysis sets
No evidence found.
Results
Participant disposition
Participants remaining on treatment at the data cut-off
Discontinuation due to adverse events
Baseline characteristics
Line of therapy and anatomic subtype
Age, sex, and performance status at baseline
No evidence found.
Efficacy results
Response and survival outcomes as reported at the congress
Response and survival outcomes as summarized in the trial design publication
Health-related quality of life and patient-reported outcomes
No evidence found.
Safety results
Treatment-related adverse events as reported at the congress
Treatment-emergent adverse events regardless of relationship, as reported by the sponsor
Study limitations
Summary
The phase 2 biliary tract cancer cohort was single-arm, open-label, and enrolled 24 participants at four sites, all in South Korea, so its 37.5% response rate has no concurrent control and was not estimated in a United States population. Responses were assessed by investigator review in the reported analysis rather than by the independent radiology review named as the registered primary outcome measure. Participants had received one or two prior systemic therapies, and the response rate differed markedly by line of therapy, 63.6% in the second line against 15.4% in the third line, so the estimate depends on the mix of lines enrolled. Two sources report different durations of response for the same cohort, a median of 9.4 months in the congress abstract and 6.9 months in the trial design publication, and median overall survival had not been reached at the August 12, 2022 data cut-off with a median follow-up of 11.8 months. Toxicity was frequent: treatment-related adverse events of grade 3 or higher were reported in 75% of participants, including one grade 5 pneumonia, and six participants (25.0%) discontinued because of a treatment-emergent adverse event. The study was terminated for a change of development plan, and the second stage of the Simon two-stage design was not conducted after the sponsor agreed with the U.S. Food and Drug Administration to move directly to a randomized trial, so the cohort was never expanded to the planned size. No baseline demographic table, quality-of-life outcome, or peer-reviewed full report of the cohort has been published.