A Study of BMS-986205 Alone and in Combination With Nivolumab in Chinese Patients With Advanced Malignant Solid Tumors: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Study of BMS-986205 Alone and in Combination With Nivolumab in Chinese Patients With Advanced Malignant Solid Tumors (NCT03792750), a non-randomized phase 1, phase 2 study. The primary outcome is The Number of Participants Experiencing Adverse Events (AE).

2. Clinical Question

The study’s stated purpose was to evaluate pharmacokinetics, pharmacodynamics, safety, and tolerability of BMS-986205 alone and with nivolumab in Chinese patients with advanced malignant solid tumors. The primary outcome focused on the number of participants experiencing adverse events, rather than a direct comparison of treatment strategies.

The treatment sequence matters for interpreting the question: participants first received BMS-986205 monotherapy for a 2 week lead-in and then received the combination. As a result, the overall safety experience includes more than one treatment period. The primary outcome timeframe ran from first dose to 100 days after the last dose of study therapy, up to approximately 2 years.

The record also lists secondary outcomes including objective response rate, best overall response, duration of response, serum kynurenine and tryptophan measurements, and anti-drug antibodies to nivolumab. Numerical results for these outcomes are not reported in the registry record. The available information therefore supports description of the study question and its reported safety counts, but not an assessment of tumor response or biomarker changes.

3. Trial Design

This was a Phase 1/2, nonrandomized, single-group study with no masking. The registry records enrollment of 12 participants and lists the study as completed. The start date was 2018-12-31 and the primary completion date was 2020-12-18.

Participants in Experimental Arm A received a 2 week BMS-986205 monotherapy lead-in, followed by BMS-986205 plus nivolumab. Because the registry identifies one treatment group and no random allocation, the study does not provide a concurrent control group for estimating what would have happened under another treatment. Participants’ outcomes can be described, but differences between treatment options cannot be attributed to this study design.

The primary outcome was the number of participants experiencing adverse events among all treated participants. The specified observation period extended from first dose to 100 days after the last dose of study therapy, up to approximately 2 years. The record defines an adverse event as a new untoward medical occurrence or worsening of a preexisting medical condition after study treatment; the event does not need to be caused by the treatment.

The listed secondary outcomes span clinical response, response duration, laboratory measurements, and anti-drug antibodies. The registry record does not report numerical results for those outcomes. It also does not report a detailed statistical analysis plan, the precise eligibility criteria, treatment doses, or the reasons for the selected design. Those details should not be inferred from the phase, study title, or treatment sequence.

The safety information includes counts of participants at risk and affected for serious and other adverse-event categories, as well as a count of deaths and selected serious-event terms. These are descriptive findings from a small single-group study, not comparative estimates. The record does not establish whether events were judged related to treatment, except that the primary outcome definition explicitly does not require a causal relationship.

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.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: All Treated Participants

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.

6. Primary Endpoint

The registry lists the primary outcome as The Number of Participants Experiencing Adverse Events (AE), measured over From first dose to 100 days after last dose of study therapy (up to approximately 2 years).

The primary endpoint is the number of treated participants who experienced adverse events during the period from first dose to 100 days after the last dose of study therapy, up to approximately 2 years. It is a participant count, not a count of every event episode, and the registry identifies the analysis population as all treated participants.

An adverse event is defined broadly: it includes a new untoward medical occurrence or worsening of a preexisting condition in a participant who received study treatment. The event need not be caused by the treatment. This distinction is important because an adverse event occurring during a study is not, by that fact alone, evidence of a treatment-caused harm.

Counting participants with events is useful in a safety evaluation because it gives a direct description of how many people had at least one event during the observation period. It does not describe event severity, duration, recurrence, or the number of separate episodes unless those details are reported separately. Nor does an unadjusted count account for differences in how long participants were observed.

The record names this count as the primary outcome but does not give its numerical result in the available results information. Separate adverse-event summaries report participants affected by serious and other event categories, but they should not automatically be treated as a complete numerical result for the primary endpoint. The registry record does not report the operational relationship between those categories and the primary outcome in enough detail to equate them.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does a participant count represent?

A participant count records how many people experienced an outcome, rather than how many times the outcome occurred. In safety reporting, a person with repeated episodes may still contribute only once to a count of participants with at least one event. Event counts and participant counts answer different questions. The primary outcome is explicitly a count of participants experiencing adverse events, while the registry’s safety summary separately presents affected-participant counts for serious and other categories.

A count is easy to interpret descriptively, but it does not convey precision by itself. The uncertainty around a count depends on the number of people observed, the event definition, and the amount of follow-up. The registry record does not provide a confidence interval for the primary outcome or enough information to calculate one. General statistical interpretation: a confidence interval expresses a range of values compatible with the data under a specified statistical model; it does not make a descriptive study comparative.

Why does the single-group design matter?

In a randomized comparison, treatment groups can be compared using an analysis that reflects the allocation and outcome data. This study was nonrandomized and single-group, with no separate comparator. Its observed event counts therefore describe the participants in the study, but cannot estimate a relative difference between BMS-986205 with nivolumab and another treatment or no treatment. General statistical principle: without a concurrent comparator, changes over time and outcomes during treatment may reflect several influences, including disease course and other care.

The treatment sequence includes a monotherapy lead-in and then combination therapy. An overall count across the study period does not, by itself, distinguish events occurring during the lead-in from those occurring during combination treatment. The registry record does not report phase-specific event counts or a method for attributing events to one component of the sequence.

How should adverse-event definitions be read?

The primary outcome definition includes new medical occurrences and worsening preexisting conditions, without requiring a causal relationship to study treatment. This is a broad safety-surveillance definition. A reported event is therefore not automatically a treatment-related event. Establishing attribution would require additional information, such as investigator assessments and event-level context; those details are not reported in the registry record.

Serious events are a safety category, while the primary endpoint is framed as participants experiencing adverse events. The registry lists participants affected by serious and other events, but does not explain in the available information whether these categories are mutually exclusive or how they map to the primary outcome. They should be read as separate descriptive summaries rather than combined or treated as interchangeable measures.

What do the planning assumptions mean?

The record describes planning illustrations based on an observed effect, using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It says that the effect to detect is a stated fraction of the observed effect. For time-to-event settings, the illustration concerns total events; for other settings, it concerns participants per arm.

These are planning assumptions, not a description of this trial’s actual design. The study itself has one group and was not randomized, so an equal-allocation, two-arm illustration does not describe the enrolled treatment structure. The record does not report the numerical planning estimates in the available information, and no sample-size calculation can be reconstructed in the registry record reported. A planning calculation is not observed power: it does not measure the probability that this completed study detected an effect.

General statistical principle: a sample-size plan depends on the outcome, the target effect, variability or event frequency, allocation, and the chosen error rate. If an illustration uses an effect observed in a study, it is conditional on that effect estimate and is not a substitute for a prospectively specified design justification. The registry record does not report the study’s sample-size justification or explain whether the posted planning assumptions were used when the study was designed.

What can be concluded when outcome results are absent?

Study objectives and outcome names describe what investigators intended to evaluate; they are not numerical findings. The registry lists response and laboratory outcomes, but their numerical results are not reported in the registry record. No effect estimate or precision measure for those outcomes can therefore be interpreted from the available information. General statistical principle: an estimate is more informative when accompanied by uncertainty, but neither an estimate nor its uncertainty can be inferred solely from an endpoint label.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("BMS-986205 in Combination With Nivolumab")
n      <- c(12)
events <- c(11)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  BMS-986205 in Combination With Nivolumab  12  11  91.7  61.5  99.8  64.6  98.5  64.0  98.1

11. Multiplicity, Missing Data and Analysis Populations

The registry lists multiple secondary outcomes, including objective response rate, best overall response, duration of response, serum kynurenine and tryptophan measurements, and anti-drug antibodies to nivolumab. It also reports 21 outcome measures. Evaluating many outcomes can raise multiplicity concerns: when multiple statistical tests are conducted, the chance of at least one apparently notable result can increase. General statistical approaches include prespecifying a primary comparison, adjusting for multiple testing, or treating secondary findings as exploratory. The registry record does not report which approach, if any, was used.

The record does not report a detailed statistical analysis plan, a testing hierarchy, or interim analyses. It therefore does not establish how the listed outcomes were prioritized or whether any formal adjustment for multiplicity was planned. Numerical results for the listed efficacy and laboratory outcomes are not reported in the registry record, so their multiplicity cannot be evaluated from results.

The primary outcome population is described as all treated participants. The registry does not report the number analyzed for each outcome, participant-level missingness, reasons for missing data, or a missing-data method. It also does not report how discontinuations or incomplete follow-up were handled. These omissions limit interpretation of whether the reported safety summaries reflect the full intended observation period for every participant.

The safety summary lists 12 at risk for the serious and other event categories, but the record does not provide enough detail to establish the completeness of follow-up or how missing records were handled. No inference about the direction or impact of missing data is justified. The registry record also does not report a formal analysis population beyond the primary outcome’s all-treated description.

12. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 5% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: malignant neoplasm progression (16.7%), tuberculosis (8.3%), acute kidney injury (8.3%), pneumonitis (8.3%).

The safety summary lists 3 participants affected by serious adverse events among 12 at risk, and 11 affected by other adverse events among 12 at risk. It separately records 3 deaths. These are participant counts from the study group, not comparisons with another treatment group. The registry record does not report whether the deaths were judged related to study treatment.

The listed top serious-event terms are malignant neoplasm progression at 16.7%, tuberculosis at 8.3%, acute kidney injury at 8.3%, and pneumonitis at 8.3%. These percentages are reported as serious-event terms in the registry summary. They do not show causation, and the record does not give the event-level detail needed to determine whether a participant had more than one listed event.

Serious adverse events and other adverse events are distinct summary categories, but the registry record does not state whether a participant can appear in both. The counts should not be added or interpreted as separate groups of people. General safety-reporting principle: observed events during a clinical study may be related to treatment, the underlying illness, or other factors; an event’s occurrence alone does not establish its cause.

13. What the Result Does, and Does Not, Mean

The posted safety data describe adverse events recorded in a small, single-group study of BMS-986205 followed by combination treatment with nivolumab. The record lists participants affected by serious and other adverse-event categories, deaths, and selected serious-event terms. Those findings are relevant as descriptive safety observations, but the registry information does not establish that the study drugs caused any particular event.

The primary outcome is defined as the number of treated participants experiencing adverse events over a specified follow-up period. Its numerical result is not reported in the registry record. The safety summaries therefore provide some observed safety information without supplying a complete numerical result for the named primary endpoint. The record also does not report numerical response, response-duration, or biomarker results, so no efficacy or pharmacodynamic conclusion can be drawn from those outcome names.

The single-group, nonrandomized design has no concurrent control. It cannot estimate how the observed outcomes compare with another treatment strategy. Any such comparison would require additional data and assumptions that are not reported. The treatment sequence further means that overall observations do not, on their own, distinguish outcomes during BMS-986205 alone from those during combination therapy.

These results should not be interpreted as proof that an event was caused by treatment, nor as evidence that a treatment is effective or ineffective. The registry record supports a limited account of what was recorded and identifies substantial gaps in the numerical results needed for broader statistical interpretation. A completed study can still have outcomes whose numerical results are not reported in the registry record.

14. Why This Trial Matters Statistically

This trial illustrates why study design and outcome reporting are central to statistical interpretation. The record identifies a Phase 1/2 study with a single treatment group, a monotherapy lead-in, and subsequent combination therapy. That structure can describe the experience of treated participants, but it does not create a randomized or concurrent-control estimate of comparative benefit or harm.

It also highlights the distinction between an outcome definition and an outcome result. The primary endpoint is clearly framed as a count of treated participants experiencing adverse events within a specified observation period, yet its numerical result is not reported in the registry record. The available adverse-event summaries add useful descriptive counts, but their relationship to the primary endpoint is not fully explained.

Safety records can also be misread when event occurrence is conflated with causality. The definition includes events that need not be caused by study treatment, and the listed serious-event terms do not themselves determine attribution. Similarly, deaths are recorded, but the registry information does not say whether they were treatment-related.

Finally, the record’s planning assumptions illustrate the difference between a hypothetical sample-size exercise and the design that was actually conducted. An illustration based on two arms and equal allocation does not describe a nonrandomized single-group study. Keeping these distinctions clear prevents planning calculations, outcome labels, and descriptive counts from being mistaken for comparative evidence.

15. 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 principal limitation is the absence of a concurrent comparator. Because the study was nonrandomized and used a single group, the recorded outcomes cannot separate treatment effects from other influences or support a direct between-group estimate. The treatment sequence also combines a monotherapy lead-in with later combination therapy; the registry does not report phase-specific results that would distinguish their safety experiences.

The registry lists 12 enrolled participants, which limits how broadly descriptive counts can be generalized. The safety summary identifies participants at risk and affected, but the record does not provide participant-level follow-up, event timing, duration, recurrence, or detailed attribution. The recorded deaths are not accompanied by a treatment-relatedness assessment in the available information.

The numerical result for the stated primary endpoint is not reported in the registry record. Numerical results for the listed response and laboratory outcomes are also not reported. Thus, the available information does not permit assessment of the magnitude or precision of those outcomes, or of how they were analyzed.

Further details are not reported in the registry record, including the statistical analysis plan, missing-data methods, analysis populations beyond the primary outcome’s all-treated description, multiplicity procedures, and sample-size justification. The record also does not give enough detail to determine whether serious and other adverse-event categories overlap. These limitations call for a descriptive rather than comparative reading of the reported safety information.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: A Study of BMS-986205 Alone and in Combination With Nivolumab in Chinese Patients With Advanced Malignant Solid Tumors — NCT03792750.
• Registry record last updated 2022-02-28; status last verified 2022-02.
• Results first posted 2022-02-28.
• 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.

19. Record Summary

The registry record describes NCT03792750, a completed Phase 1/2 study of BMS-986205 alone and in combination with nivolumab in Chinese patients with advanced malignant solid tumors. It was nonrandomized, unmasked, and single-group, with enrollment of 12. The treatment sequence began with a 2 week BMS-986205 monotherapy lead-in and continued with combination therapy.

The primary outcome was the number of treated participants experiencing adverse events from first dose to 100 days after the last dose of study therapy, up to approximately 2 years. The numerical result for that endpoint is not reported in the registry record. The safety summary lists 3 participants with serious adverse events, 11 with other adverse events, and 3 deaths among 12 at risk for the reported event categories. Numerical results for the listed response and laboratory outcomes are not reported in the registry record.