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 Comparison of Finasteride and Tamsulosin for Treatment of Benign Prostatic Hyperplasia (BPH) (MK-0906A-149 AM2) (NCT01534351), a randomized phase 3 study. The primary outcome is Change From Baseline in International Prostate Symptom Score (IPSS).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01534351 |
| Phase | Phase 3 |
| Condition | Benign Prostatic Hyperplasia |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 1 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Merck Sharp & Dohme LLC |
| Results posted | Yes |
2. Clinical Question
Population
The intended population was Asian men aged at least 50 years with benign prostatic hyperplasia. The registry describes a Full Analysis Set, but the posted record does not report a completed analysis population or comparative results.
Intervention
The combination regimen was finasteride 5 mg and tamsulosin 0.2 mg, taken orally once daily for 12 months. The registry also lists finasteride-matching and tamsulosin-matching placebos.
Comparator
The planned monotherapy groups received finasteride 5 mg or tamsulosin 0.2 mg orally once daily for 12 months, alongside the corresponding matching placebo. The record describes the combination and monotherapy regimens but does not report results comparing them.
Primary question
The study intended to assess whether combination treatment improved BPH symptoms, measured by change in the International Prostate Symptom Score (IPSS), compared with finasteride alone. Its summary also describes a hypothesis about prostate-volume reduction compared with tamsulosin alone. Neither hypothesis has a reported analysis result in the registry record.
The central statistical question is comparative: whether outcomes differ between planned treatment groups, and how precisely any difference is estimated. Answering it requires outcome observations and an analysis that accounts for the trial design. The registry reports an enrollment of 1 and 0 analyses. It therefore does not establish a treatment-group contrast, estimate an effect, or indicate the precision of an effect estimate.
The study was intended to examine both symptoms and prostate volume, but the registry identifies change from baseline in IPSS as the primary outcome. It gives no numerical outcome values, estimated differences, confidence intervals, or significance tests. The clinical questions describe the trial’s aims; they are not findings about the effects of either regimen.
3. Trial Design
The registry describes a phase III randomized, double-masked, parallel-group clinical trial. It lists three treatment groups: finasteride, tamsulosin, and finasteride with tamsulosin. Each monotherapy regimen included a matching placebo for the other drug. The planned treatment period was 12 months. These design features describe the intended comparison; they do not establish that the planned groups were populated or that comparative analyses were completed.
The registry records an enrollment of 1 and a status of terminated. It lists a study start date of 2013-08-01 and a primary completion date of 2013-11-18. The record does not explain why the trial was terminated or how the enrollment relates to the planned treatment groups. It also does not report the number assigned to each group or the number who completed follow-up.
Randomized allocation and double masking are stated design characteristics. Details about the randomization sequence, allocation concealment, masking procedures, and any assessment of whether masking was maintained are not reported in the registry record. The registry also does not describe the planned statistical model or the intended handling of deviations from assigned treatment.
The intended population was Asian men aged at least 50 years with BPH. The primary outcome was change from baseline in IPSS at Month 12. Although the study summary additionally describes a prostate-volume hypothesis, the posted results do not give a numerical comparison for either outcome. With an enrollment of 1 and 0 analyses, the record does not support interpreting the trial as a completed comparison of the treatment regimens.
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: Prior to early study discontinuation, 3 sites were initiated and screened a total of 8 participants. Of the 8 participants, one participant was randomized to finasteride 5 mg once daily for 39 days.
Overall Study
| Stage | Finasteride | Tamsulosin | Finasteride and Tamsulosin |
|---|---|---|---|
| STARTED | 1 | 0 | 0 |
| COMPLETED | 0 | 0 | 0 |
| NOT COMPLETED | 1 | 0 | 0 |
Reasons for not completing this period:
| Reason | Finasteride | Tamsulosin | Finasteride and Tamsulosin |
|---|---|---|---|
| Study Terminated Early | 1 | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: Full Analysis Set (FAS) - population consists of all randomized participants who received at least one dose of study treatment, at least one post-randomization observation for the analysis endpoint, and baseline data for those analyses that require baseline data. As only one participant was randomized in the study, no analyses were performed.
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.
| Characteristic | Unit | Finasteride | Tamsulosin | Finasteride and Tamsulosin | Total |
|---|---|---|---|---|---|
| Participants analysed | 1 | 0 | 0 | 1 | |
| Age, Categorical: <=18 years | Participants | 0 | — | — | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 1 | — | — | 1 |
| Age, Categorical: >=65 years | Participants | 0 | — | — | 0 |
| Sex: Female, Male: Female | Participants | 0 | — | — | 0 |
| Sex: Female, Male: Male | Participants | 1 | — | — | 1 |
6. Primary Endpoint
The registry lists the primary outcome as Change From Baseline in International Prostate Symptom Score (IPSS), measured over Baseline and Month 12.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is change from baseline in the International Prostate Symptom Score (IPSS), assessed at baseline and Month 12. The IPSS is a self-administered questionnaire intended to measure the severity of lower urinary tract symptoms among men suspected of having symptomatic BPH. It contains seven urinary-symptom questions covering frequency, nocturia, weak stream, hesitancy, intermittence, incomplete emptying, and urgency. Each response contributes to a total symptom score; higher totals indicate greater symptom severity.
The questionnaire also includes a quality-of-life question, but that question is not included in the total symptom score. The registry describes the quality-of-life response as a separate global rating of how a participant feels about current urinary symptoms. Keeping it separate means that the primary symptom score reflects the seven symptom items rather than combining symptom severity with the global quality-of-life response.
Change from baseline is used to express how a participant’s recorded symptom score differs from the starting assessment. Comparing that change between treatment groups would address whether symptom trajectories differed over the planned follow-up. The registry supplies the endpoint definition and timeframe, but no observed score changes or between-group estimates. The endpoint’s measurement description is therefore not evidence of a treatment effect.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies a comparative trial but does not report comparative outcome estimates. It lists an enrollment of 1, a terminated status, and 0 analyses. For the primary outcome, it names change from baseline in IPSS at Month 12, but gives no group-specific scores, changes, treatment contrast, confidence interval, or p-value. The intended clinical question cannot be answered from the posted results.
The record’s planned hypotheses should be read as objectives, not conclusions. The summary describes a symptom comparison of finasteride plus tamsulosin against finasteride alone, and a prostate-volume comparison against tamsulosin alone. No reported analysis establishes the direction or size of either contrast. The registry also does not report numerical prostate-volume results.
An enrollment of 1 is not enough information to reconstruct the trial’s intended group comparison. The record does not say which group that enrollee entered, whether outcome assessments were collected, or whether any participant met the stated analysis-population criteria. The adverse-event entries list 1 participant at risk in the finasteride group and 0 in each of the other listed groups. Those entries do not constitute comparative safety estimates.
Precision cannot be assessed because there are no reported effect estimates or uncertainty intervals. General statistical interpretation: an estimate describes the observed contrast, while a confidence interval describes the range of values compatible with the data under the analysis assumptions. Without an estimate and its uncertainty, readers cannot judge whether the data distinguish among materially different possible effects. The absence of a reported p-value likewise does not imply a null finding; it means that the registry record does not report a test result.
The study’s termination and limited recorded enrollment constrain what can be learned from this record. They do not, by themselves, explain why the study stopped, whether the reason was statistical or operational, or what would have happened in a completed trial. Those details are not reported in the registry record. Any conclusion about efficacy, comparative safety, or the reasons for termination would go beyond the posted data.
9. Statistical Methods Explained
The registry states that allocation was randomized, masking was double, and the study used a parallel-group model. It does not report the detailed statistical methods used for an outcome analysis, and the analysis count is 0. The explanations below describe general statistical concepts that would be relevant to interpreting a randomized comparison; they are not claims about methods used in this trial.
What does randomization contribute?
General explanation: random allocation is intended to make treatment groups comparable, on average, with respect to measured and unmeasured characteristics at the time of assignment. This supports interpreting a between-group contrast as an estimate of the effect of assignment, subject to the trial’s implementation and analysis assumptions. Randomization does not guarantee that small groups will be balanced, and it cannot compensate for absent outcome data. The registry does not report sequence generation, allocation concealment, or a completed group comparison.
What is the role of masking?
General explanation: masking is intended to reduce the influence of treatment knowledge on participant reports, clinical care, and outcome assessment. The registry describes the trial as double-masked and lists matching placebos for the monotherapy regimens. It does not explain who was masked, how masking was maintained, or whether it was assessed. A design label alone cannot show how well masking worked in practice.
What would a treatment contrast mean?
General explanation: a treatment contrast compares an outcome between groups, using a defined scale and analysis population. For this trial’s primary endpoint, a contrast would concern change in IPSS from baseline to Month 12. The contrast could be reported as a difference in mean changes or through another prespecified method, but the registry does not state which method was planned or used. No such contrast is reported, so none can be interpreted.
Why are uncertainty intervals important?
General explanation: an estimate alone does not show how much uncertainty remains. A confidence interval communicates the sampling uncertainty under a particular model and set of assumptions. A narrow interval generally indicates greater precision than a wide interval, while either interval must be interpreted in light of the outcome scale and the design. The posted results contain no estimate or interval for the primary outcome. The degree of precision is therefore not reported.
What does a significance test tell a reader?
General explanation: a significance test evaluates compatibility between observed data and a specified null hypothesis under the test’s assumptions. A p-value is not the probability that the null hypothesis is true, nor does it measure clinical importance. Its interpretation depends on the analysis plan, outcome definition, and handling of multiple comparisons. No p-value or testing procedure is reported for this trial, so no statistical significance conclusion can be drawn.
Why can dispersion matter?
General explanation: outcome variability affects the precision of a group estimate and the ability to distinguish a contrast from random variation. Analyses that assume a particular variance structure may be inappropriate if the data are more variable than that structure allows; over-dispersion is one example of this mismatch. The registry gives no outcome summaries or variability estimates for IPSS, and it does not identify an analysis model. There is no basis to assess whether over-dispersion or another distributional issue applied.
How should a planning calculation be understood?
General explanation: a sample-size calculation is a planning exercise based on assumptions about the effect to detect, variability, allocation, and chosen error rates. It is not evidence that a trial achieved a particular probability of finding an effect, and it is not a result from participants. The record describes a planning illustration based on a fraction of an observed effect and specifies a two-sided significance level of 0.05, equal allocation, and a normal approximation. It does not report a usable observed effect estimate or a trial analysis from which to assess that illustration. Any planning value should therefore not be interpreted as observed power or as evidence of an outcome.
The registry does not report a prespecified model, covariate adjustment, assumptions for missing observations, or a hierarchy of tests. Those details cannot be inferred from the randomized, double-masked, parallel design. Without a reported analysis and its assumptions, readers cannot evaluate model fit, the treatment estimand, or the robustness of any result.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 4 outcome measures and 0 analyses. The primary outcome is change from baseline in IPSS at Baseline and Month 12. The study summary also describes a prostate-volume hypothesis. However, the record does not report a completed analysis of either outcome or explain how the outcomes were ordered for confirmatory testing.
Multiplicity arises when several outcomes, time points, treatment contrasts, or statistical tests are considered. General explanation: examining multiple comparisons can increase the chance that at least one result appears statistically notable by chance, so a planned testing strategy can help control interpretation. The registry does not report a multiplicity adjustment, testing hierarchy, or interim-analysis plan. It is not possible to tell whether any such methods were planned or used.
The registry describes a Full Analysis Set as randomized participants who received at least one dose, had at least one post-randomization observation for the analysis endpoint, and had baseline data for analyses requiring baseline data. It does not report the number meeting those criteria or provide outcome results for that population. The record also does not state whether an intention-to-treat population or another analysis population was used in a completed analysis.
Missing-data methods are not reported in the registry record. There is no account of missing endpoint assessments, reasons for missingness, imputation, or sensitivity analyses. General explanation: missing-data assumptions matter because conclusions can depend on how unobserved outcomes are handled, particularly when missingness differs among groups or relates to outcome status. In the absence of reported observations and methods, the impact of missing data cannot be assessed.
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 |
|---|---|---|---|
| Finasteride | 0 | 1 | 0.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Finasteride | 0 of 1 |
| Tamsulosin | 0 of 0 |
| Finasteride and Tamsulosin | 0 of 0 |
The serious and other adverse-event entries are counts for participants at risk and participants affected, by listed treatment group. For finasteride, the record lists 1 participant at risk, 0 affected by serious adverse events, and 1 at risk with 0 affected by other adverse events. For tamsulosin and for finasteride and tamsulosin, it lists 0 participants at risk and 0 affected in both categories.
These counts should not be read as evidence that adverse events did not occur in the groups with 0 participants at risk. There is no recorded at-risk population in those entries from which to estimate an event frequency. Even in the finasteride group, the displayed counts describe only the recorded participant count; they do not provide a comparative rate or a precise safety estimate. The registry lists no serious adverse-event terms.
The death fields are null, not numerical event counts. The record does not report a comparative safety analysis, exposure-adjusted rates, event timing, or a detailed account of adverse-event ascertainment. These registry entries therefore describe limited recorded counts and cannot establish comparative safety across the planned regimens.
12. What the Result Does, and Does Not, Mean
The record shows that a phase III randomized, double-masked, parallel-group trial was registered to compare finasteride and tamsulosin alone or in combination for BPH. Its stated primary endpoint was change from baseline in IPSS at Month 12. The registry records enrollment of 1, a terminated status, and 0 analyses. Those details describe the status and reporting available in the registry; they do not provide an estimate of treatment effect.
The record does not show whether combination treatment changed symptoms more or less than finasteride alone. Nor does it show whether prostate volume changed differently between the combination and tamsulosin groups. There are no reported endpoint values, group comparisons, uncertainty intervals, or test results on which to base those conclusions. No result should be inferred from the study hypotheses or the endpoint definitions.
The posted adverse-event counts are limited and should not be treated as a comparison of safety. The listed groups have unequal recorded at-risk counts, including zero in two groups. Such entries do not provide the exposure or outcome information needed to compare event risks reliably.
General interpretation: a trial’s design can describe how a comparison was intended to be conducted, while its results require observed outcomes and transparent analyses. A randomized label does not itself establish that a treatment effect was estimated, and termination does not reveal the direction of an effect. The reason for termination and the intended statistical plan are not reported in the registry record.
Accordingly, this record is informative about the study’s aim, planned regimens, primary endpoint, and limited enrollment status. It does not determine whether any regimen was more effective or safer than another. The findings that would be needed for those judgments are not reported in the registry record.
13. Why This Trial Matters Statistically
This trial illustrates why design information and outcome evidence need to be distinguished. The registry describes a randomized, double-masked comparison and gives a defined symptom endpoint, but the recorded enrollment is 1 and the analysis count is 0. Without outcome data and a completed comparison, the intended design cannot answer the treatment question.
It also illustrates why an endpoint definition is not an endpoint result. The IPSS description explains what was meant to be measured and how the symptom score is constructed. It does not show how participants scored, how scores changed, or whether changes differed by group. Keeping that distinction clear prevents a study objective from being mistaken for evidence.
Safety counts need the same care. A zero count of affected participants in a group with zero participants at risk cannot be interpreted as an observed absence of events among treated participants. Counts require denominators and context before they can support comparisons. Here, the available adverse-event entries are too limited to establish a comparative safety profile.
For biostatisticians and clinical researchers, the record also underscores the importance of reporting analysis populations, missing-data methods, effect estimates, and uncertainty. These details allow readers to evaluate what population a result addresses and how precisely it is estimated. They are not reported for this trial. The study remains statistically relevant as an example of the limits of interpreting design intentions when completed analyses and outcome estimates are unavailable.
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 primary limitation for interpretation is the absence of reported comparative analyses. The registry records 0 analyses and does not give numerical results for the primary IPSS endpoint. No treatment effect, confidence interval, p-value, or group-specific outcome summary is reported. The clinical hypotheses therefore remain untested in the posted results.
Enrollment was 1, and the study status is terminated. The record does not explain the termination, identify the treatment group for the recorded enrollee, or report completion and follow-up counts. It also does not state whether the planned 12-month assessments were obtained. These gaps prevent assessment of the intended group comparisons and their precision.
The registry describes the intended population as Asian men aged at least 50 years with BPH, but no analyzed population is reported. The Full Analysis Set definition is stated, while the number meeting its criteria and any corresponding outcomes are not given. The record does not report eligibility details beyond the summary description or provide enough information to assess generalizability from observed participants.
The analysis plan, missing-data procedures, multiplicity strategy, and details of randomization and masking are not reported. The adverse-event counts are also too limited for a comparative safety assessment, with zero participants at risk recorded in two treatment groups. These limitations are specific to the information in this registry record; they do not establish why the study ended or what results might have been observed with fuller enrollment.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Comparison of Finasteride and Tamsulosin for Treatment of Benign Prostatic Hyperplasia (BPH) (MK-0906A-149 AM2) — NCT01534351.
- Registry record last updated 2018-08-29; status last verified 2018-07.
- Results first posted 2015-12-03.
- 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
NCT01534351 is a phase III randomized, double-masked, parallel-group trial of finasteride, tamsulosin, and their combination for BPH. The intended population was Asian men aged at least 50 years. Planned treatment was once daily for 12 months, and the primary endpoint was change from baseline in IPSS at Month 12.
The registry lists an enrollment of 1 and a status of terminated. It records 4 outcome measures and 0 analyses. No comparative efficacy estimates or confidence intervals are reported. The adverse-event entries list 1 participant at risk in the finasteride group and 0 in the other listed groups, with no affected participants recorded; these counts do not establish comparative safety.
The registry record describes study aims and design, but does not report results that answer the planned treatment comparisons. The reason for termination, detailed statistical plan, and missing-data methods are not reported.