This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for A Study of TAK-659 in Combination With Nivolumab in Participants With Advanced Solid Tumors (NCT02834247), a non-randomized phase 1 study. The primary outcome is Part 1, Dose Escalation Phase: Maximum Tolerated Dose (MTD).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02834247 |
| Phase | Phase 1 |
| Condition | Triple-Negative Breast Neoplasms, Carcinoma, Non-Small-Cell Lung, Head and Neck Carcinoma, Squamous Cell |
| Allocation | Non-Randomized |
| Design model | Sequential |
| Masking | None (open label) |
| Enrollment | 41 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Calithera Biosciences, Inc |
| Results posted | Yes |
2. Clinical Question
Population
Participants with advanced solid tumors were eligible for the study. The registry identifies triple-negative breast cancer, non-small-cell lung cancer, and head and neck squamous cell carcinoma among the conditions and describes a dose-expansion part for metastatic disease in those groups.
Intervention
The study evaluated TAK-659 in combination with nivolumab. In Part 1, the record describes TAK-659 doses of 60 mg, 80 mg, and 100 mg with nivolumab 3 mg/kg. In Part 2, TAK-659 was to be given at the recommended Phase 2 dose identified in Part 1 with nivolumab.
Comparator
There was no randomized control group. The registry describes a nonrandomized, sequential study, so the dose groups are not like-for-like control arms. Differences between groups cannot be interpreted as randomized treatment effects.
Primary question
In Part 1, the primary endpoint was the maximum tolerated dose of TAK-659 with nivolumab, assessed using dose-limiting toxicities during the first treatment cycle. The broader study purpose also included evaluating a recommended Phase 2 dose, safety, and efficacy. Numerical results for the primary endpoint and efficacy outcomes are not reported in the registry record.
This is a dose-finding question rather than a confirmatory comparison of treatments. The study design asks whether the combination can be evaluated across dose levels and identifies a dose range using early-cycle toxicity. The registry also describes planned dose expansion in selected tumor groups, but does not report numerical disease-control, survival, or response results. Accordingly, the record supports a description of the design and reported safety counts, not a conclusion about comparative benefit or efficacy.
3. Trial Design
The registry describes a Phase 1b, nonrandomized, unmasked, sequential study. Enrollment is listed as 41, and the status is terminated. The recorded study start is 2016-08-12 and the primary completion date is 2018-11-30. The reason for termination is not reported in the registry record.
Part 1 was a dose-escalation phase in participants with advanced solid tumors. The listed combination groups used TAK-659 at 60 mg, 80 mg, or 100 mg with nivolumab 3 mg/kg. TAK-659 was described as an oral daily tablet during 28-day cycles; nivolumab was described as an intravenous infusion on Days 1 and 15 of each cycle. Treatment was described as continuing until progression or unacceptable toxicity. The registry identifies dose-limiting toxicities during the first cycle as the basis for the maximum tolerated dose endpoint.
Part 2 was a dose-expansion phase for metastatic triple-negative breast cancer, non-small-cell lung cancer, and head and neck squamous cell carcinoma. Participants were to receive TAK-659 at the recommended Phase 2 dose determined in Part 1 with nivolumab. The record also describes a possible nivolumab fixed-dose cohort after the recommended Phase 2 dose was identified; whether that cohort was carried out is not reported in the registry record.
Because allocation was nonrandomized and sequential, dose groups should not be treated as randomized comparisons. The registry does not report allocation details beyond this description, nor does it provide a concurrent control group. The posted results list safety counts for four groups, including a Part 2 triple-negative breast cancer group; numerical efficacy results are not reported in the registry record.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Before assignment: Participants with advanced solid tumors and metastatic TNBC were enrolled in Parts 1 and 2 respectively. Part 2 cohorts: TNBC cohort was discontinued due to insufficient efficacy of drug. Study was terminated before start of potential fixed dose cohort, non-small cell lung cancer cohort and head and neck squamous cell carcinoma cohort.
Dose Escalation Phase
| Stage | Part 1: TAK-659 60 mg + Nivolumab 3 mg/kg | Part 1: TAK-659 80 mg + Nivolumab 3 mg/kg | Part 1: TAK-659 100 mg + Nivolumab 3 mg/kg | Part 2: TAK-659 80 mg + Nivolumab 3 mg/kg (TNBC) |
|---|---|---|---|---|
| STARTED | 8 | 11 | 5 | 0 |
| COMPLETED | 0 | 0 | 0 | 0 |
| NOT COMPLETED | 8 | 11 | 5 | 0 |
Reasons for not completing this period:
| Reason | Part 1: TAK-659 60 mg + Nivolumab 3 mg/kg | Part 1: TAK-659 80 mg + Nivolumab 3 mg/kg | Part 1: TAK-659 100 mg + Nivolumab 3 mg/kg | Part 2: TAK-659 80 mg + Nivolumab 3 mg/kg (TNBC) |
|---|---|---|---|---|
| Study Terminated by Sponsor | 1 | 2 | 0 | 0 |
| Death | 5 | 6 | 5 | 0 |
| Lost to Follow-up | 0 | 1 | 0 | 0 |
| Withdrawal by Subject | 2 | 2 | 0 | 0 |
Dose Expansion Phase
| Stage | Part 1: TAK-659 60 mg + Nivolumab 3 mg/kg | Part 1: TAK-659 80 mg + Nivolumab 3 mg/kg | Part 1: TAK-659 100 mg + Nivolumab 3 mg/kg | Part 2: TAK-659 80 mg + Nivolumab 3 mg/kg (TNBC) |
|---|---|---|---|---|
| STARTED | 0 | 0 | 0 | 17 |
| COMPLETED | 0 | 0 | 0 | 0 |
| NOT COMPLETED | 0 | 0 | 0 | 17 |
Reasons for not completing this period:
| Reason | Part 1: TAK-659 60 mg + Nivolumab 3 mg/kg | Part 1: TAK-659 80 mg + Nivolumab 3 mg/kg | Part 1: TAK-659 100 mg + Nivolumab 3 mg/kg | Part 2: TAK-659 80 mg + Nivolumab 3 mg/kg (TNBC) |
|---|---|---|---|---|
| Study Terminated by Sponsor | 0 | 0 | 0 | 7 |
| Death | 0 | 0 | 0 | 8 |
| Lost to Follow-up | 0 | 0 | 0 | 1 |
| Withdrawal by Subject | 0 | 0 | 0 | 1 |
Analysis population for the primary outcome, as defined in the registry: The DLT-evaluable population was defined as participants who had met the minimum treatment and safety evaluation requirements of the study and/or who experienced a DLT during Cycle 1.
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
Population: The safety population was defined as all the participants who received at least 1 dose of study drug.
| Characteristic | Unit | Part 1: TAK-659 60 mg + Nivolumab 3 mg/kg | Part 1: TAK-659 80 mg + Nivolumab 3 mg/kg | Part 1: TAK-659 100 mg + Nivolumab 3 mg/kg | Part 2: TAK-659 80 mg + Nivolumab 3 mg/kg (TNBC) | Total |
|---|---|---|---|---|---|---|
| Participants analysed | 8 | 11 | 5 | 17 | 41 | |
| Age, Continuous | years | 57.8 (SD 8.53) | 51.2 (SD 16.04) | 56.8 (SD 16.22) | 49.2 (SD 8.62) | 52.3 (SD 12.08) |
| Sex: Female, Male: Female | Participants | 5 | 8 | 2 | 17 | 32 |
| Sex: Female, Male: Male | Participants | 3 | 3 | 3 | 0 | 9 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 0 | 0 | 1 | 0 | 1 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 8 | 10 | 4 | 15 | 37 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 1 | 0 | 2 | 3 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 0 | 2 | 0 | 1 | 3 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 1 | 0 | 1 | 2 | 4 |
| Race (NIH/OMB): White | Participants | 7 | 9 | 4 | 12 | 32 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 | 2 | 2 |
| Region of Enrollment: Spain | Participants | 0 | 0 | 0 | 9 | 9 |
| Region of Enrollment: United Kingdom | Participants | 0 | 0 | 0 | 2 | 2 |
| Region of Enrollment: United States | Participants | 8 | 11 | 5 | 6 | 30 |
| Height | centimeter (cm) | 166.09 (SD 11.473) | 166.58 (SD 11.360) | 167.00 (SD 5.523) | 164.03 (SD 8.245) | 165.48 (SD 9.334) |
| Weight | kilogram (kg) | 71.75 (SD 19.006) | 60.11 (SD 17.393) | 73.62 (SD 13.646) | 69.50 (SD 12.266) | 67.92 (SD 15.572) |
6. Primary Endpoint
The registry lists the primary outcome as Part 1, Dose Escalation Phase: Maximum Tolerated Dose (MTD), measured over At end of Cycle 1 Day 28.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | mg |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint was the maximum tolerated dose of TAK-659 in combination with nivolumab during Part 1. The registry defines the maximum tolerated dose as the dose range at which less than or equal to 1 of 6 evaluable participants experience a dose-limiting toxicity within the first 28 days of treatment, ending at Cycle 1 Day 28. Toxicities were evaluated using National Cancer Institute Common Terminology Criteria for Adverse Events version 4.03.
The endpoint uses early toxicity to guide dose selection. In general, an early-phase dose-finding study uses such a rule to distinguish doses that produce a level of acute toxicity considered tolerable for further study. The endpoint is not a measure of tumor response, long-term safety, or comparative treatment effect. It also depends on which participants qualify as evaluable: the registry defines the DLT-evaluable population as participants who met minimum treatment and safety evaluation requirements and/or experienced a dose-limiting toxicity during Cycle 1.
The registry record does not report a numerical maximum tolerated dose, the number of dose-limiting toxicities by dose, or the size of the DLT-evaluable population. A recommended Phase 2 dose is part of the study purpose and dose-expansion description, but its numerical value is not reported in the registry record. The endpoint definition therefore clarifies what the study intended to measure, but does not establish the dose selected or the observed toxicity pattern that informed selection.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record supplies a study design, a primary endpoint definition, and some safety counts, but it does not provide a numerical result for the maximum tolerated dose. It lists 12 outcome measures and no formal analyses. Numerical results for the listed disease-control, duration-of-response, progression-free-survival, overall-survival, or pharmacokinetic outcomes are not reported in the registry record. The record therefore does not allow a statistical assessment of efficacy or a quantitative comparison of outcomes across the dose groups.
For safety, the posted results report, for each of four groups, the number at risk for serious adverse events and the number affected. The counts are 6 of 8 for Part 1 at TAK-659 60 mg with nivolumab 3 mg/kg; 7 of 11 for Part 1 at 80 mg with nivolumab 3 mg/kg; 4 of 5 for Part 1 at 100 mg with nivolumab 3 mg/kg; and 12 of 17 for the Part 2 triple-negative breast cancer group at 80 mg with nivolumab 3 mg/kg. These are descriptive counts, not evidence from a randomized comparison. The group sizes are small, and the groups differ in dose, study part, and—in the Part 2 group—tumor type. Any apparent differences across these counts may reflect those design and population differences as well as chance.
The record lists deaths for the same groups: 5, 6, 5, and 8, respectively. It does not report cause, timing, attribution, or whether these deaths were considered treatment-related. The counts alone cannot answer those questions. Nor do they establish that treatment caused or prevented any event.
The registry lists serious adverse event terms including sepsis, pyrexia, pneumonitis, respiratory failure, acute respiratory failure, and Pneumocystis jirovecii pneumonia, with percentages attached to the terms. Their denominators and the detailed method used to construct these percentages are not reported in the registry record. The percentages should therefore be read as registry-listed event summaries, not as directly comparable risks across the dose groups.
Overall, the posted information permits cautious description of the study’s intended dose-finding framework and selected safety counts. It does not support a treatment-effect estimate, a conclusion about efficacy, or a precise estimate of risk. The sponsor’s own analysis takes precedence when reported; no formal analyses or primary endpoint result are listed in this record.
9. Statistical Methods Explained
The registry describes a sequential, nonrandomized study. In general, sequential dose-finding evaluates participants in a planned progression through dose levels, using accumulating safety information to inform later evaluation. This differs from random assignment: participants are not allocated by chance to concurrent treatment arms intended for a like-for-like comparison. Here, the registry lists Part 1 dose levels and a later Part 2 expansion, but does not report a detailed statistical dose-escalation algorithm. The exact decision process beyond the stated maximum tolerated dose definition is not reported in the registry record.
What does the primary endpoint rule mean?
The stated rule defines the maximum tolerated dose as a dose range at which no more than 1 of 6 evaluable participants has a dose-limiting toxicity within Cycle 1. This is a threshold rule for interpreting early toxicity, not a statistical test of whether one treatment is better than another. It focuses on a specified observation period and a defined analysis population. Events outside that period do not enter the endpoint as defined, although the registry separately lists broader adverse-event outcomes. The record does not provide dose-specific DLT counts or identify which dose met the rule.
The evaluable population is also important. The registry says participants had to meet minimum treatment and safety evaluation requirements and/or experience a DLT during Cycle 1. In general, restricting an analysis to evaluable participants can make the denominator differ from the number enrolled or treated. The registry does not report the number meeting this definition at each dose, or how participants who did not meet the requirements were handled in the endpoint analysis.
How should safety counts be read?
The posted safety results give counts of participants at risk and counts affected for serious adverse events and other adverse events. These counts are descriptive summaries. In general, a count is most informative when its denominator and event definition are clear; a proportion can communicate the observed frequency within a group, but cannot by itself show that treatment caused an event. No new proportions or comparisons are calculated. The registry also reports group-specific death counts, but does not report whether deaths were attributed to treatment or provide details about timing or cause.
Serious adverse event terms are listed with percentages. A percentage requires a denominator and a rule for deciding which events contribute. Those details are not reported in the registry record for the listed terms. In general, adverse-event summaries can count participants, events, or events within a particular period, and these are not interchangeable measures. The term-level percentages should not be interpreted as a direct comparison among dose groups without the corresponding definitions and denominators.
What do confidence intervals and p-values contribute?
In general, a confidence interval describes the range of estimates compatible with a statistical method and its assumptions. It communicates uncertainty around an estimate; it does not guarantee that the true value lies within the interval. A p-value describes how unusual data at least as extreme as the observed data would be under a specified null model. It is not the probability that a treatment works, and it does not measure the size or clinical importance of an effect. No confidence intervals or p-values for treatment outcomes are reported in the registry record. Without outcome estimates and their uncertainty, the precision of an efficacy or safety effect cannot be assessed.
Over-dispersion is a general issue for count outcomes: observed counts may vary more than a simple statistical model expects. When that occurs, standard errors based on the simpler model can be too small, making intervals too narrow or tests too optimistic. The registry record does not report a count model, an over-dispersion assessment, or an adjustment for it. This general consideration should not be mistaken for a claim that over-dispersion occurred in this study.
What does the planning illustration represent?
The described sample-size planning approach uses a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It uses a stated fraction of an observed effect as the effect to detect. For time-to-event outcomes, the planning quantity is the total number of events under a Schoenfeld approach; for other outcomes, it is participants per arm. These are planning illustrations based on an observed effect, not observed power and not evidence that the trial was designed with those sample sizes. The registry record does not report an observed effect estimate or the numerical planning results, so no sample-size value can be interpreted from the record alone.
More broadly, the planning assumptions describe an illustrative calculation, while the study itself was nonrandomized and sequential. The assumptions of equal allocation and a two-arm comparison do not make the actual dose groups randomized or exchangeable. A planning calculation cannot correct for differences in dose, study part, or disease group, and it cannot substitute for a prespecified statistical analysis or observed outcome data.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 12 outcome measures, including the Part 1 maximum tolerated dose endpoint; treatment-emergent adverse events, Grade 3 or 4 adverse events, serious adverse events, and adverse events leading to discontinuation; disease control and duration of response; progression at Month 6; progression-free survival and overall survival; and TAK-659 pharmacokinetic measures. These outcomes address different questions and may use different populations, time frames, and analysis methods.
When several outcomes are tested, general statistical practice considers multiplicity: the more tests conducted, the greater the chance of at least one apparently unusual result under a set of null hypotheses. Common approaches include identifying a primary endpoint in advance, specifying a testing hierarchy, or adjusting inference across selected tests. The registry record does not report a multiplicity strategy, a hierarchy for secondary outcomes, or formal analysis results. It is therefore not possible to determine how any set of outcome tests was handled.
Missing-data methods are also not reported in the registry record. The primary endpoint has a DLT-evaluable population definition, but the record does not state how missing toxicity assessments, incomplete follow-up, or participants who were not evaluable were addressed in a numerical analysis. For the listed response and time-to-event outcomes, the record does not report censoring rules, follow-up completeness, or methods for handling missing assessments. These omissions limit interpretation because the analyzed population and observation time can affect an outcome estimate.
The record distinguishes the DLT-evaluable population from the overall study enrollment but provides no count of evaluable participants by dose. Analysis populations for the secondary outcomes are not reported in the registry record. The outcome list alone does not reveal which populations were analyzed or whether all enrolled participants contributed to each measure.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Part 1: TAK-659 60 mg + Nivolumab 3 mg/kg | 6 | 8 | 75.0% |
| Part 1: TAK-659 80 mg + Nivolumab 3 mg/kg | 7 | 11 | 63.6% |
| Part 1: TAK-659 100 mg + Nivolumab 3 mg/kg | 4 | 5 | 80.0% |
| Part 2: TAK-659 80 mg + Nivolumab 3 mg/kg (TNBC) | 12 | 17 | 70.6% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Part 1: TAK-659 60 mg + Nivolumab 3 mg/kg | 5 of 8 |
| Part 1: TAK-659 80 mg + Nivolumab 3 mg/kg | 6 of 11 |
| Part 1: TAK-659 100 mg + Nivolumab 3 mg/kg | 5 of 5 |
| Part 2: TAK-659 80 mg + Nivolumab 3 mg/kg (TNBC) | 8 of 17 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Part 1: TAK-659 60 mg + Nivolumab 3 mg/kg | 8 of 8 |
| Part 1: TAK-659 80 mg + Nivolumab 3 mg/kg | 11 of 11 |
| Part 1: TAK-659 100 mg + Nivolumab 3 mg/kg | 5 of 5 |
| Part 2: TAK-659 80 mg + Nivolumab 3 mg/kg (TNBC) | 17 of 17 |
Most frequent serious adverse event terms
| Event term | Organ system | Part 1: TAK-659 60 mg + Nivolumab 3 mg/kg | Part 1: TAK-659 80 mg + Nivolumab 3 mg/kg | Part 1: TAK-659 100 mg + Nivolumab 3 mg/kg | Part 2: TAK-659 80 mg + Nivolumab 3 mg/kg (TNBC) |
|---|---|---|---|---|---|
| Pyrexia | General disorders | 1 of 8 | 1 of 11 | 1 of 5 | 4 of 17 |
| Pneumonitis | Respiratory, thoracic and mediastinal disorders | 0 of 8 | 0 of 11 | 1 of 5 | 3 of 17 |
| Dyspnoea | Respiratory, thoracic and mediastinal disorders | 1 of 8 | 1 of 11 | 0 of 5 | 1 of 17 |
| Sepsis | Infections and infestations | 2 of 8 | 0 of 11 | 1 of 5 | 0 of 17 |
| Respiratory failure | Respiratory, thoracic and mediastinal disorders | 0 of 8 | 0 of 11 | 1 of 5 | 1 of 17 |
| Fatigue | General disorders | 1 of 8 | 1 of 11 | 0 of 5 | 0 of 17 |
| Breast cancer | Neoplasms benign, malignant and unspecified (incl cysts and polyps) | 0 of 8 | 0 of 11 | 0 of 5 | 2 of 17 |
| Confusional state | Psychiatric disorders | 1 of 8 | 1 of 11 | 0 of 5 | 0 of 17 |
| Acute respiratory failure | Respiratory, thoracic and mediastinal disorders | 0 of 8 | 0 of 11 | 1 of 5 | 0 of 17 |
| Pleural effusion | Respiratory, thoracic and mediastinal disorders | 0 of 8 | 0 of 11 | 0 of 5 | 1 of 17 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Part 1: TAK-659 60 mg + Nivolumab 3 mg/kg | Part 1: TAK-659 80 mg + Nivolumab 3 mg/kg | Part 1: TAK-659 100 mg + Nivolumab 3 mg/kg | Part 2: TAK-659 80 mg + Nivolumab 3 mg/kg (TNBC) |
|---|---|---|---|---|---|
| Aspartate aminotransferase increased | Investigations | 2 of 8 | 6 of 11 | 4 of 5 | 7 of 17 |
| Diarrhoea | Gastrointestinal disorders | 4 of 8 | 6 of 11 | 2 of 5 | 6 of 17 |
| Dyspnoea | Respiratory, thoracic and mediastinal disorders | 3 of 8 | 5 of 11 | 1 of 5 | 9 of 17 |
| Fatigue | General disorders | 5 of 8 | 4 of 11 | 3 of 5 | 5 of 17 |
| Alanine aminotransferase increased | Investigations | 2 of 8 | 6 of 11 | 3 of 5 | 5 of 17 |
| Anaemia | Blood and lymphatic system disorders | 3 of 8 | 6 of 11 | 2 of 5 | 4 of 17 |
| Hypophosphataemia | Metabolism and nutrition disorders | 2 of 8 | 7 of 11 | 1 of 5 | 4 of 17 |
| Hypokalaemia | Metabolism and nutrition disorders | 2 of 8 | 8 of 11 | 0 of 5 | 3 of 17 |
| Pyrexia | General disorders | 2 of 8 | 3 of 11 | 2 of 5 | 6 of 17 |
| Amylase increased | Investigations | 0 of 8 | 6 of 11 | 3 of 5 | 4 of 17 |
Serious events with the highest arm-level rate: sepsis (25.0%), pyrexia (23.5%), pneumonitis (20.0%), respiratory failure (20.0%), acute respiratory failure (20.0%).
The posted serious adverse event results give counts for four groups. In Part 1, 6 of 8 participants in the 60 mg TAK-659 plus nivolumab 3 mg/kg group were affected; 7 of 11 in the 80 mg group were affected; and 4 of 5 in the 100 mg group were affected. In Part 2, 12 of 17 participants in the 80 mg triple-negative breast cancer group were affected. These figures describe the registry’s group-level counts. They are not randomized comparisons, and the groups differ in dose, study part, and population.
The record also lists deaths of 5, 6, 5, and 8 in those groups, respectively. It does not report whether these deaths were related to treatment, their causes, or when they occurred. The counts should not be interpreted as treatment-attributable deaths.
Listed serious-event terms include sepsis at 25.0%, pyrexia at 23.5%, pneumonitis at 20.0%, respiratory failure at 20.0%, acute respiratory failure at 20.0%, and Pneumocystis jirovecii pneumonia at 20.0%. The registry record does not report the denominators or detailed calculation rules for these percentages. They should not be compared as if they were group-specific rates. In general, serious-event summaries describe reported events; they do not alone establish causation or quantify risk relative to an untreated or randomized control group.
12. What the Result Does, and Does Not, Mean
The registry record establishes that this was a Phase 1b, nonrandomized, sequential study evaluating TAK-659 with nivolumab in advanced solid tumors. It specifies a Part 1 maximum tolerated dose endpoint based on dose-limiting toxicity during the first treatment cycle and describes a planned Part 2 expansion in selected metastatic tumor groups. The record also gives selected adverse-event and death counts.
Those design details do not establish the numerical maximum tolerated dose, the recommended Phase 2 dose, or an efficacy result. The numerical primary endpoint result is not reported in the registry record. Neither are numerical results for the listed response, disease-control, progression-free-survival, or overall-survival outcomes. The safety counts are descriptive and do not show what would have happened under a different treatment or under no treatment.
In general, a nonrandomized dose-escalation study is suited to characterizing early safety and informing dose selection, but its dose groups are not automatically comparable. Differences in group composition, dose, study part, and tumor type complicate cross-group interpretation. The design also does not provide a randomized counterfactual for estimating a treatment effect. The posted information therefore cannot establish that TAK-659 with nivolumab improves outcomes or that it does not.
The record’s missing outcome analyses are material. Without numerical endpoint estimates, denominators for some event summaries, uncertainty intervals, or a reported analysis plan, readers cannot assess precision, statistical significance, or the stability of any apparent pattern. The trial’s terminated status is recorded, but the reason for termination is not reported in the registry record and should not be inferred from that status.
The appropriate conclusion is limited: the record documents the study’s dose-finding question and some safety summaries, while leaving the main numerical outcome results and important analysis details unreported. These limitations define what can be learned from the registry record; they are not evidence for either efficacy or lack of efficacy.
13. Why This Trial Matters Statistically
This trial illustrates why early-phase studies and confirmatory treatment comparisons answer different statistical questions. A sequential dose-finding study uses information about toxicity at successive dose levels to guide dose selection. Its main inferential target is not necessarily a treatment-effect contrast, and its dose groups should not be treated like randomized arms. The distinction matters when readers encounter counts by dose and are tempted to rank the groups as if dose were the only difference.
The primary endpoint is framed around a defined early observation window and a DLT-evaluable population. That makes the endpoint rule interpretable in principle, while also showing why the denominator and evaluability criteria matter. Without dose-specific DLT counts or a numerical maximum tolerated dose result, the definition alone cannot reveal which dose range satisfied the rule.
The registry also lists several secondary outcomes spanning safety, response, survival, and pharmacokinetics. Each has a different statistical meaning and may require its own population definition and handling of follow-up or missing observations. The lack of reported formal analyses and outcome estimates prevents readers from assessing uncertainty, multiplicity, or the strength of evidence across those outcomes.
Finally, the safety figures demonstrate the difference between descriptive reporting and causal inference. Counts can document events among participants, but a nonrandomized study without a control group cannot establish how those event counts compare with an alternative treatment. The study is statistically informative as an example of a dose-finding design and of the limits imposed by incomplete result reporting; the record does not support broader claims about treatment effects.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The main limitation for interpreting this trial is that the registry record does not report a numerical result for its primary endpoint. Although it defines the maximum tolerated dose and the DLT-evaluable population, it does not give the dose-specific DLT counts, the number evaluable at each dose, or the numerical maximum tolerated dose. The recommended Phase 2 dose is discussed as a basis for Part 2, but its value is not reported in the registry record.
The study was nonrandomized and sequential, with different dose levels and a later expansion in a specified tumor group. The posted safety groups therefore do not form a like-for-like comparison. Differences in observed counts cannot isolate dose effects from differences in study part or disease population. No concurrent randomized control group is described.
The safety reporting is incomplete for interpretation of event risk. The record provides serious adverse event counts and a list of serious-event terms with percentages, but does not report the denominator or detailed calculation method for those term-level percentages. It lists deaths without reporting cause, timing, or treatment attribution. The record also does not give a detailed approach to missing safety assessments or the analysis population used for each secondary outcome.
Numerical efficacy and pharmacokinetic results are not reported in the registry record, and no formal analyses are listed. The reason for termination, detailed statistical analysis plan, missing-data methods, and multiplicity approach are also not reported in the registry record. These limitations prevent assessment of outcome precision and restrict interpretation to the design and descriptive results that are recorded.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: A Study of TAK-659 in Combination With Nivolumab in Participants With Advanced Solid Tumors — NCT02834247.
- Registry record last updated 2023-02-08; status last verified 2023-02.
- Results first posted 2020-03-31.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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18. Record Summary
This record concerns a Phase 1b, nonrandomized, unmasked, sequential study of TAK-659 with nivolumab in participants with advanced solid tumors. Enrollment is listed as 41. The study status is terminated; its recorded start is 2016-08-12 and primary completion date is 2018-11-30.
Part 1 evaluated dose escalation, with maximum tolerated dose as the primary endpoint. Part 2 was described as dose expansion in metastatic triple-negative breast cancer, non-small-cell lung cancer, and head and neck squamous cell carcinoma. The record reports selected serious adverse event and death counts, but does not report the numerical maximum tolerated dose, formal analyses, or numerical efficacy results.
The study has no randomized control group, so its dose groups are not like-for-like treatment comparisons. The reason for termination and several analysis details are not reported in the registry record. The posted information supports a description of the design and selected safety counts, but not a comparative treatment-effect estimate.