Efficacy of SNX-1012 in the Treatment of Oral Mucositis: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Efficacy of SNX-1012 in the Treatment of Oral Mucositis (NCT00385515), a randomized phase 2 study. The primary outcome is Duration of Ulcerative Oral Mucositis.

2. Clinical Question

3. Trial Design

The registry describes a Phase 2, randomized, double-masked, placebo-controlled study with a parallel-group model. The masking field is listed as quadruple. The trial is marked completed, with enrollment of 81. The study title identifies patients receiving cytotoxic chemotherapy for breast or lung cancer; the listed conditions are stomatitis and oral mucositis.

The active arm received SNX-1012 tablets dissolved in water for oral swish and expectorate at 30 mg 4 times daily for 10 days. The placebo tablets were matched to SNX-1012 and used for oral swish and expectorate 4 times daily for 10 days. The record lists the study start as 2006-06 and primary completion as 2008-05. These dates describe the registry record and do not add detail about recruitment or follow-up.

The primary outcome results are reported for 44 participants in the SNX-1012 group and 21 in the placebo group. The primary outcome description states that the analysis includes subjects randomized to the 30mg dose of SNX-1012. The registry’s overall enrollment figure is 81; the reason the outcome-group counts are different from the overall enrollment is not reported in the registry record.

The primary measure was a continuous outcome: duration of ulcerative oral mucositis in days, summarized as a mean and standard deviation. The registry also lists a secondary outcome counting participants with ulcerative oral mucositis. Details of allocation procedures, recruitment flow, and the original sample-size justification 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: 533 subjects were screened during a chemotherapy cycle and those that developed ulcerative oral mucositis and fully recovered were randomized to treatment with study drug during the next chemotherapy cycle

Overall Study

Analysis population for the primary outcome, as defined in the registry: Analysis only includes subjects randomized to the 30mg dose of SNX-1012

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 Duration of Ulcerative Oral Mucositis, measured over At least 10 consecutive days beginning on Day 1 of a chemotherapy cycle.

The primary endpoint is the duration of ulcerative oral mucositis, measured in days. The registry says trained evaluators directly observed all randomized subjects for at least 10 consecutive days during the chemotherapy cycle. The observation period was defined as beginning on Day 1 of a chemotherapy cycle. The duration description focuses on subjects who developed recurrent ulcerative oral mucositis; the stated study purpose refers to reducing the duration of Grade 2, 3, or 4 oral mucositis according to World Health Organization criteria.

Duration is a continuous outcome: it records how long the condition persists rather than only whether it occurs. A group mean gives a summary of average duration, while the standard deviation describes how dispersed individual durations are around that average. These summaries answer different questions. The mean describes the group average; the spread indicates how much individual observations vary.

Using duration is relevant to the stated research question because the study was designed to evaluate time spent with ulcerative oral mucositis, not only its presence. The registry does not report additional operational details about how onset, resolution, or recurrence were adjudicated, beyond direct observation by trained evaluators during the stated period.

7. Results Posted in the Registry

• SNX-1012: mean 2.30 versus 3.20 on control; difference -0.90 (95% CI -3.09 to 1.29), standardized effect d = -0.25; z-test p = 0.421.

8. Secondary Efficacy Endpoints

The registry also posts results for secondary outcomes. For each outcome below, the endpoint type, the test applied to the posted summary statistics, the result and its interpretation are given in turn. Secondary endpoints are usually not adjusted for multiple testing, so they support rather than confirm the primary finding.

Number of Participants With Ulcerative Oral Mucositis

• Endpoint type: Binary: the number of participants with the event, compared as proportions.
• Test: Unadjusted two-proportion z-test, with a Wald 95% confidence interval for the risk difference.
• Result:
  • SNX-1012: 50.0% (22/44) versus 52.4% (11/21) on control; risk difference -2.4 percentage points (95% CI -28.4 to 23.6), risk ratio 0.95 (0.58–1.58); unadjusted two-proportion z-test p = 0.857.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between SNX-1012 and the control. The interval gives the range of effects that remain compatible with the data.

The secondary outcome addresses whether participants had ulcerative oral mucositis, whereas the primary outcome addresses duration among the stated primary analysis population. These measures are related because both concern oral mucositis during the chemotherapy-cycle observation period, but they describe different features: occurrence and duration. A comparison in occurrence does not directly establish a difference in duration, and an average duration contrast does not establish a difference in occurrence.

Across the posted results, the secondary estimate is close to zero on the risk-difference scale and its confidence interval includes zero. This broadly aligns with the primary result in that neither posted comparison provides a precise, clear separation between groups. The outcomes nevertheless have distinct interpretations and should not be combined into a single claim. The primary endpoint remains the duration measure identified by the registry as the main outcome.

The registry lists no reported analyses for the secondary outcome. Its displayed group counts and calculated contrasts can be described, but there is no accompanying report of a prespecified statistical test or adjustment plan for this endpoint. The secondary result is therefore best treated as supportive descriptive context, not as an independently confirmed conclusion.

Unadjusted secondary results carry less weight because multiple outcomes or comparisons create more opportunities to observe an apparently notable result by chance. General statistical principle: when a study evaluates several outcomes, an analysis plan may define how to control the overall error rate or distinguish primary from exploratory analyses. Such a plan is not reported in the registry record. The secondary finding should not be promoted to the same evidential status as the primary outcome or interpreted as a separate confirmation of it.

The secondary outcome relates to the primary question but does not resolve the primary interval’s uncertainty. In particular, it cannot explain the substantial variation in duration or establish that the mean contrast is meaningful. Reading outcomes together is useful for understanding the scope of the evidence, but each needs to retain its own scale, population, and uncertainty.

Secondary outcomes registered for this trial, for reference (only those above were recalculated):

• Number of Participants With Ulcerative Oral Mucositis

9. Statistical Interpretation

10. Statistical Methods Explained

The primary endpoint is a continuous measure, duration in days, and the registry summarizes it using a mean and standard deviation. A mean difference compares the arithmetic averages in two groups. In this record, the contrast is defined as the SNX-1012 mean minus the placebo mean. A negative estimate therefore indicates a lower posted average in the SNX-1012 group, without by itself establishing why that difference arose or whether it is distinguishable from chance variation.

What does the confidence interval describe?

In general, a confidence interval describes a range of values reasonably compatible with the observed data and the method’s assumptions. It represents uncertainty about the estimated group contrast, not the range containing most individual participants’ durations. The interval for the primary mean difference extends from -3.094 to 1.294 days and includes zero. That breadth is important: the data do not pinpoint the contrast with high precision, and the range includes both directions of difference.

What does the p-value add?

In general, a p-value quantifies how unusual data at least as inconsistent with a specified null hypothesis would be if that null hypothesis and the test assumptions held. It does not give the probability that the null hypothesis is true, and it does not measure the size or clinical importance of an effect. The primary unadjusted p-value is 0.421. The secondary unadjusted p-value is 0.857. Because the registry does not report the test specification or a broader analysis plan, these values should be interpreted as posted unadjusted results rather than as evidence that all planned inferential requirements were met.

Why do the standard deviations matter?

A standard deviation describes variation among observations within a group. The posted standard deviations are 3.04 days for SNX-1012 and 4.68 days for placebo. General statistical principle: when individual values vary considerably, group averages can be estimated less precisely, especially when the analysis groups are limited in size. Here, the posted dispersion and the confidence interval both reinforce that the mean difference is uncertain. A mean difference also summarizes only the average contrast; it does not show the distribution’s shape or whether a small number of long durations influence the mean.

What does the secondary outcome measure?

The secondary outcome is a binary measure summarized by the number of participants with ulcerative oral mucositis. A risk difference compares the proportions in the two groups, with the posted estimate expressed as SNX-1012 minus placebo. Its confidence interval ranges from -0.283 to 0.236, crossing zero. The record also contains relative-risk and odds-ratio summaries, but the registry lists no reported analyses for this outcome. Those effect measures express group contrasts on different scales; they should not be treated as independent findings because they are derived from the same underlying outcome counts.

Why can variability affect planning?

General statistical principle: over-dispersion means that observed variation is greater than a model or analysis assumes. If an analysis assumes less variability than is present, its uncertainty estimates and planning requirements may be too optimistic. The registry does not report a model-based analysis of over-dispersion, and no such conclusion should be inferred from the summaries alone. The observed standard deviations do, however, describe substantial variation that is relevant when considering the precision of the estimated mean contrast.

The posted comparison is an unadjusted summary. Whether the analysis adjusted for baseline characteristics, chemotherapy regimen, cancer type, or other factors is not reported in the registry record. The exact statistical test, model, handling of repeated observations, and treatment of values that might be censored or unavailable are also not reported in the registry record. The posted estimates can be described, but the registry does not support reconstruction of a more detailed analysis method.

11. Confidence Intervals and Precision

Precision concerns how tightly the data locate an effect estimate. The primary mean difference is -0.9 days, with a 95% confidence interval from -3.094 to 1.294 days. The interval spans zero, so it is compatible with no average difference. It also covers differences in both directions, including a shorter average duration in the SNX-1012 group and a longer average duration in that group. The estimate is therefore not precise enough to resolve the direction of the underlying contrast.

A confidence interval is not an assurance that the true value lies within its limits in this one study. In general, it describes the behavior of an interval-generating method across repeated samples under its assumptions. Its interpretation depends on the validity of the analysis and the study data. The registry does not report enough statistical detail to assess every assumption behind the posted interval.

The secondary risk-difference interval, -0.283 to 0.236, also includes zero and allows for differences in either direction. It is a separate outcome and scale, so its numerical width should not be compared directly with the duration interval. Both intervals indicate uncertainty, but they answer different questions.

The primary group standard deviations, 3.04 and 4.68 days, show notable variation in duration. Together with the unequal posted analysis counts of 44 and 21, that variation helps explain why a point estimate should not be read as a settled result. The registry does not report a prespecified threshold for a clinically important difference, so the intervals cannot be judged against such a threshold from this record alone.

12. Planning a Similar Trial: Sample Size

This is a planning illustration, not a re-evaluation of the original trial. It asks: if a new study wanted to detect a difference like the one observed, or a smaller one, how large would it need to be? It is deliberately not “observed power” of the finished trial, which is not a meaningful quantity.

The planning figures are illustrations based on the observed effect, not the trial’s original design justification. The registry’s planning assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. Each row uses the stated fraction of the observed effect as the effect to detect. The outcome is not time-to-event, so the figures are participants per arm, not total events.

The 80% power column gives the planned number of participants per arm under those assumptions for a design with an 80% chance of detecting the specified effect, if that effect and the planning model are correct. The 90% column gives the corresponding per-arm planning figure for a design with a 90% chance. These are prospective design calculations, not guarantees about the result of any study.

The rows that plan for 100% of the observed effect use the full observed contrast as the target. The rows planning for 75% and 50% use smaller target effects. Smaller effects require more participants to distinguish them from random variation at the same stated power and significance level. This explains why the participant requirements rise as the target effect is reduced.

For the primary outcome, the planning figures are 257 participants per arm for 80% power and 345 for 90% power when planning for 100% of the observed effect; they increase for the smaller-effect scenarios. The figures are not observed power and do not say what power the completed trial had. The original trial’s sample-size assumptions are not reported in the registry record.

13. How the Sample Size Is Derived

Power is the probability that a study of a given size rejects the null hypothesis when a specific true effect exists. It depends on four things: the effect to detect, the variability of the outcome, the significance level (here a two-sided α of 0.05, so z_1−α/2 = 1.960) and the desired power (z_1−β = 0.842 for 80% and 1.282 for 90%).

Formula

n is the number of participants in each arm, Δ is the difference in means to detect and σ is the common standard deviation.

Worked calculation for this trial

1. Observed difference Δ = -0.900; pooled standard deviation σ = 3.642.
2. n = 2 × (1.96 + 0.842)² × 3.642² / -0.900² = 257.0, rounded up to 257 participants per arm for 80% power.

The smaller-effect rows in the table above repeat the same calculation with the effect multiplied by 0.75 and 0.5 (for ratios, applied to the logarithm of the ratio).

R code

alpha <- 0.05
z_a   <- qnorm(1 - alpha / 2)          # two-sided
delta <- -0.9                      # observed difference in means
sigma <- 3.64155208493598                     # pooled standard deviation
n_per_arm <- function(power, frac = 1) {
  ceiling(round(2 * (z_a + qnorm(power))^2 * sigma^2 / (delta * frac)^2, 6))
}
for (f in c(1, 0.75, 0.5))
  cat(sprintf("%3.0f%% of observed effect: n per arm = %s (80%% power), %s (90%% power)\n", 100 * f,
              format(n_per_arm(0.80, f), big.mark = ","), format(n_per_arm(0.90, f), big.mark = ",")))

# Check against R's built-in function (t-based, so very slightly larger)
cat("power.t.test:", round(power.t.test(delta = delta, sd = sigma, power = 0.80)$n, 1), "\n")

# Simulation: exact two-sample t-test using simulated means and variances
set.seed(385515)
n    <- n_per_arm(0.80)
reps <- 20000
m_diff <- rnorm(reps, delta, sigma * sqrt(2 / n))             # difference in sample means
s2     <- sigma^2 * rchisq(reps, 2 * (n - 1)) / (2 * (n - 1))   # pooled sample variance
tstat  <- m_diff / sqrt(s2 * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(tstat) > qt(0.975, 2 * (n - 1))), reps))

Output from running the code

100% of observed effect: n per arm = 257 (80% power), 345 (90% power)
 75% of observed effect: n per arm = 457 (80% power), 612 (90% power)
 50% of observed effect: n per arm = 1,028 (80% power), 1,377 (90% power)
power.t.test: 258 
Simulated power at n = 257 per arm: 0.800 (20000 replicates)

The simulation draws many sets of group means and variances at the planned sample size and counts how often the two-sample t-test rejects the null. It should land close to the target power; at very small required sample sizes it can fall below it, because the normal approximation is rough there.

14. Multiplicity, Missing Data and Analysis Populations

Multiplicity concerns the increased chance of a false-positive finding when many hypotheses or outcomes are examined. This record identifies one primary endpoint and one secondary outcome, but a complete list of all planned analyses and comparisons is not reported in the registry record. The multiplicity strategy, including whether any adjustment was planned or applied, is not reported in the registry record. The secondary p-value is explicitly unadjusted, and no reported analyses are listed for the secondary outcome.

Without a stated analysis hierarchy or adjustment procedure, secondary results should be regarded cautiously. This does not alter the values posted for the primary endpoint, but it affects how multiple findings from the same trial should be interpreted together. The original statistical analysis plan and any prespecified rules for selecting outcomes are not reported in the registry record.

The primary outcome description identifies the analysis population as subjects randomized to the 30mg dose of SNX-1012. The listed primary group counts are 44 and 21. The corresponding analysis population for the secondary outcome, beyond the group counts shown, is not described in detail. Reasons for the difference between overall enrollment of 81 and the primary outcome counts are not reported in the registry record.

Missing-data handling is not reported in the registry record. The record does not explain whether outcome data were unavailable for any participants, how unavailable observations were treated, or whether any sensitivity analyses were conducted. The presence or absence of missing observations therefore cannot be inferred from the reported counts alone. The protocol’s rules for exclusions, deviations, and analysis populations are also not reported in the registry record.

The registry gives no details on interim analyses, stopping rules, or a formal statistical analysis plan. These details are relevant to assessing how outcomes and analyses were selected, but their absence from the record does not establish that a particular procedure was or was not used. Interpretation should remain limited to the analyses and descriptions actually recorded.

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

The posted results describe an estimated difference in average ulcerative oral mucositis duration of -0.9 days for SNX-1012 relative to placebo. The negative sign indicates that the SNX-1012 group had a lower posted mean duration. The confidence interval includes zero and extends in both directions, and the unadjusted p-value is 0.421. These statistics do not provide a precise estimate of the direction or size of the underlying difference.

The results do not establish that SNX-1012 reduced duration, and they do not establish that the groups had identical duration. A non-significant result is not proof of no effect. It may reflect uncertainty, limited information, variation in participant outcomes, or other features that cannot be distinguished from this registry record. Conversely, a point estimate favoring one group is not sufficient to establish a treatment effect.

The secondary outcome measures occurrence rather than duration. Its interval also includes zero, and it is not accompanied by reported analyses in the registry record. It provides context but does not strengthen the primary estimate into a definitive conclusion. Neither outcome alone identifies how results might differ across breast and lung cancer, chemotherapy regimens, or other participant characteristics; subgroup results are not reported in the registry record.

The trial record supports a description of a randomized, double-masked, placebo-controlled Phase 2 study and its posted outcome summaries. It does not provide all details needed to independently evaluate analysis choices, missing observations, or prespecified multiplicity control. The interpretation should therefore remain tied to the stated endpoint population and the reported comparisons rather than being generalized beyond them.

These findings are statistical descriptions of the posted data, not medical advice. They do not determine an individual patient’s care or establish a clinical recommendation. The registry record also does not report a threshold for a clinically important difference in duration, so statistical uncertainty cannot be translated into a judgment about clinical importance from these results alone.

16. Why This Trial Matters Statistically

This trial illustrates why an estimated group difference should be read alongside its uncertainty. The primary point estimate is negative, but the confidence interval includes zero and covers values on both sides. A single number can suggest a direction; the interval shows how much uncertainty remains around that suggestion. This distinction is central when interpreting small clinical trials.

The outcome is continuous and variable. Reporting means and standard deviations makes both average duration and dispersion visible, while the confidence interval quantifies uncertainty in the group contrast. The posted group sizes are also unequal, and the registry’s enrollment figure is not the same as the counts in the primary analysis. Understanding exactly which population an outcome describes is therefore as important as reading the overall enrollment.

The secondary endpoint demonstrates another statistical issue: occurrence and duration are different outcomes. They can complement one another, but neither substitutes for the other. Unadjusted results across multiple outcomes require careful interpretation, particularly when the registry does not report a multiplicity plan or formal secondary analyses.

Finally, planning illustrations based on an observed effect are not evidence about the completed trial’s achieved power. They show how assumed effect size and desired design power relate to planned participant requirements under specified assumptions. The original design assumptions are absent from the record, so the illustrations should not be mistaken for the trial’s intended sample size or justification.

17. 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 outcome population is described as subjects randomized to the 30mg dose of SNX-1012, while the registry’s overall enrollment is 81 and the primary result lists 44 and 21 participants in the outcome groups. The reason for this difference is not reported in the registry record. This limits interpretation of how the posted outcome population relates to all enrolled participants.

The primary endpoint description refers to participants who developed recurrent ulcerative oral mucositis, but additional details about outcome ascertainment, onset and resolution criteria, or handling of recurrence are not reported in the registry record. Although trained evaluators are mentioned, evaluator training procedures and reliability are not described.

The registry does not report the original sample-size justification, a complete statistical analysis plan, the exact test or model used for the primary comparison, or a multiplicity strategy. Missing-data procedures, exclusions, protocol deviations, and interim analyses are also not reported in the registry record. These gaps prevent a full assessment of prespecification and analysis robustness.

The posted confidence interval for the mean difference is broad and crosses zero. The primary group standard deviations indicate substantial variation, and the group counts are unequal. No threshold for a clinically important duration difference is reported, so clinical relevance cannot be assessed against a registry-defined benchmark. Results for subgroups, including separate results by cancer type or chemotherapy regimen, are not reported in the registry record.

18. Related Tutorials

19. Related Statistical Calculators

20. Sources

• ClinicalTrials.gov: Efficacy of SNX-1012 in the Treatment of Oral Mucositis — NCT00385515.
• Registry record last updated 2009-05-07; status last verified 2009-04.
• Results first posted 2009-03-18.
• 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.

21. Record Summary

NCT00385515 is a completed Phase 2 randomized, double-masked, placebo-controlled parallel-group study of SNX-1012 for oral mucositis in patients receiving cytotoxic chemotherapy for breast or lung cancer. The record lists enrollment of 81, a start of 2006-06, and primary completion in 2008-05.

The primary outcome was duration of ulcerative oral mucositis in days during observation for at least 10 consecutive days beginning on Day 1 of a chemotherapy cycle. The posted mean difference for SNX-1012 versus placebo was -0.9 days, with a 95% confidence interval from -3.094 to 1.294 and an unadjusted p-value of 0.421. The secondary outcome concerned the number of participants with ulcerative oral mucositis; the registry lists no reported analyses for it.

Details of the original sample-size justification, analysis plan, multiplicity handling, and missing-data procedures are not reported in the registry record.