A Study of Zoledronic Acid, Pravastatin, and Lonafarnib for Patients With Progeria: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Study of Zoledronic Acid, Pravastatin, and Lonafarnib for Patients With Progeria (NCT00879034), a na phase 2 study. The primary outcome is The Primary Objective of This Study is to Evaluate the Feasibility of Administering Intravenous Zoledronic Acid, Oral Pravastatin and Oral Lonafarnib, to Patients With Progeria for a Minimum of 4 Weeks.

2. Clinical Question

In statistical terms, the study asks a descriptive question about the experience of a small group receiving the regimen. It does not ask whether the combination produces better outcomes than another treatment or no treatment. With no control group, outcomes during treatment cannot be separated from changes that might have occurred over the same period without the regimen.

The study also set out to describe acute and chronic toxicities, identify clinical and laboratory studies relevant to monitoring or altering therapy, assess lonafarnib pharmacokinetics, assay HDJ-2 farnesylation in peripheral blood leukocytes, and obtain baseline clinical and laboratory data. These secondary objectives describe the broader feasibility and measurement aims. The registry record does not provide numerical results for those objectives in the registry record reported for this analysis.

3. Trial Design

This was a Phase II pilot study registered as a completed trial. It is described as open label, single group, and a feasibility trial. Five participants were enrolled, and the primary results are reported for the five patients who completed four weeks of therapy. There was no randomized allocation and no masking. The registry does not identify a control arm.

All participants in the reported group received the combination of zoledronic acid, pravastatin, and lonafarnib. Zoledronic acid was administered intravenously; pravastatin and lonafarnib were oral agents. The registry describes the intended initial treatment duration as four weeks, with the possibility of continuing treatment depending on tolerability. If tolerated for four weeks, treatment could continue for up to six months. The primary feasibility assessment, however, concerns the first four weeks.

The study started in 2009-03, and primary completion was recorded in 2009-04. These registry dates give the recorded study timeline but do not establish how long any participant received treatment beyond the four-week period. The registry status is completed. The record does not report the actual duration of any extensions or the number of participants who continued beyond four weeks.

The design fits an early feasibility purpose: it records whether a regimen can be administered and documents adverse events in the treated group. An open-label design means participants and study personnel were not masked to treatment. Because everyone received the same combination, the design can describe observed events during treatment but cannot make a direct between-group comparison.

Additional design details, including a planned sample size justification, any interim analyses, and a fuller statistical analysis plan, are not reported in the registry record. Allocation is listed as not applicable, consistent with the single-group description rather than a randomized comparison. No separate outcome analysis is reported in the registry fields relevant to this analysis.

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: All patients screened to participate in study were consented onto the study as planned.

Overall Study

Analysis population for the primary outcome, as defined in the registry: Results are reported for the 5 patients who completed the 4 weeks of therapy.

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 Primary Objective of This Study is to Evaluate the Feasibility of Administering Intravenous Zoledronic Acid, Oral Pravastatin and Oral Lonafarnib, to Patients With Progeria for a Minimum of 4 Weeks, measured over 4 weeks.

The primary endpoint is the number of participants with adverse events over the four-week study. The unit is participants, and the registry describes results for the five patients who completed four weeks of therapy. This is a count of people affected, not a measure of the total number of event episodes or their severity over time.

Feasibility studies use outcomes like this to describe whether a regimen can be administered for the intended initial period and to characterize tolerability-related observations. Such information can help establish whether further study is practical. In this case, the endpoint is explicitly framed around administering three agents for a minimum of four weeks, with adverse events used to assess feasibility.

The registry’s adverse-event results list zero affected participants for the reported serious adverse event category and zero for other adverse events, among five participants at risk in each category. Those categories should be read as the posted event results, not as a complete characterization of every possible safety outcome or of longer-term experience. The endpoint does not measure efficacy, and the record does not report a comparison with an untreated or alternative-treatment group.

For a binary endpoint such as whether a participant experienced an event, the count offers a direct description of what was recorded in this group. Its interpretation depends on the population, observation period, and event definitions. Here, the stated primary period is four weeks. Further definitions of event ascertainment or severity grading are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

This study has a single-group design, so its primary result is interpreted descriptively. The reported adverse-event outcome is a participant count: it records how many people were affected during the four-week study. The registry gives five participants at risk and zero affected in each of the serious and other adverse-event categories. These counts communicate the observed data directly without requiring a model-based treatment comparison.

What does a participant count represent?

A participant count differs from a count of event episodes. A person who experienced multiple events could still count once in an outcome defined as the number of participants with an event. The primary endpoint is described in participant terms, but the registry fields reported for these results distinguish serious events from other adverse events. The record does not provide event-by-event detail or a fuller operational definition of these categories.

For a binary outcome, each person is classified according to whether the event occurred during the specified observation period. In general, this kind of endpoint is straightforward to describe as a count and as the number at risk. The four-week period matters: an event count over a short period cannot describe what might occur during longer exposure. The registry’s option for treatment extension does not change the stated primary endpoint period.

Why is the design important?

Because the trial has one treatment group, no between-group contrast is available. A randomized comparison would ordinarily help distinguish differences associated with treatment from differences that might arise from other factors, but no such comparison is part of this record. The single-group result can describe what was recorded among participants receiving the combination; it cannot establish what would have happened to those same participants under a different strategy.

Open-label treatment means that masking was not used. This design feature may matter for outcomes that depend on recognition, reporting, or assessment. The registry does not describe further procedures for event ascertainment, so the extent to which outcomes were assessed independently or by standardized methods is not reported in the registry record. That uncertainty should not be filled in by assumption.

How should uncertainty be understood?

The observed count is the complete description of the posted result, but it is not a precise guarantee about the event experience of other patients. General statistical reasoning recognizes that estimates from small groups can be uncertain, even when the observed count is zero. A confidence interval can express a range of values compatible with the data under a specified method. No confidence interval or other uncertainty interval is reported for this outcome.

In general, the precision of an estimate depends on the amount and structure of the information available. Here, the results concern five completers and four weeks of observation. The registry does not report a model-based estimate or inferential analysis. Therefore, interpretation should remain at the level of the observed participants and period, rather than treating the count as a precise estimate for a wider population.

What can an analysis plan tell readers?

A statistical analysis plan ordinarily describes how outcomes are defined and summarized, what comparisons are intended, how missing observations are handled, and whether adjustments are planned. The trial record does not report a detailed statistical analysis plan, interim analyses, or a sample-size justification. It lists zero analyses in the reported analysis field. These omissions mean that readers should not infer planned tests, adjustment procedures, or a rationale for the enrollment target.

The record contains general planning assumptions for illustrative sample-size calculations, including a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It describes the target effect as a stated fraction of the observed effect. These are planning illustrations, not the design description of this single-group trial and not observed power. No resulting planning counts are reported in the registry record for this analysis. The assumptions do not supply a missing control group or establish that this study was powered for a particular comparison.

Why do event categories and follow-up matter?

Serious and other adverse events are distinct registry categories, so their counts should be read separately rather than combined into an invented total. The record reports zero affected participants in each category. It also reports zero deaths. The serious-event terms list contains no terms. These fields describe the posted safety results, but they do not provide detailed event narratives, grades, timing, or participant-level information.

General statistical interpretation also distinguishes an absence of recorded events from proof that no relevant risk exists. Event recording depends on the observation period and the way events are defined and collected. Since the primary period is four weeks and longer-term numerical results are not reported, conclusions about chronic toxicity are outside the posted data. The trial’s additional aims concerning toxicity and monitoring do not substitute for numerical findings on those objectives.

Finally, this study evaluates a three-drug combination. Even if an event had been reported, the single-group design would not identify which agent, the combination, or other factors accounted for it. Similarly, the record does not isolate the contribution of any individual drug to the feasibility observations. The statistical strength of the findings is therefore descriptive: the numbers document what was recorded in the treated group, while comparative and causal questions remain unanswered.

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("Zoledronic Acid, Pravastatin, and Lonafarnib")
n      <- c(5)
events <- c(0)
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  Zoledronic Acid, Pravastatin, and Lonafarnib  5  0  0.0  0.0  52.2  0.0  43.4  0.4  45.9

11. Multiplicity, Missing Data and Analysis Populations

The registry lists a primary feasibility objective and several secondary objectives: describing acute and chronic toxicities, identifying clinical and laboratory monitoring needs, assessing lonafarnib pharmacokinetics, assaying HDJ-2 farnesylation in peripheral blood leukocytes, and collecting baseline clinical and laboratory data. These are multiple study aims, but the registry record does not report a multiplicity strategy, such as a prespecified adjustment to account for testing multiple outcomes.

The record lists zero analyses in the reported analysis field and does not provide a detailed statistical analysis plan. It therefore does not describe which secondary outcomes were analyzed, how multiple findings would be interpreted, or whether any formal hypothesis tests were planned. Numerical results for the listed secondary objectives are not reported in the registry record.

The primary results are reported for the five patients who completed four weeks of therapy. The registry does not describe whether any participants discontinued before four weeks, how any missing outcome observations were handled, or whether the reported population was defined in advance as the analysis population. Those details are not reported in the registry record. It would be inappropriate to infer a missing-data method or an intention-to-treat analysis from the reported completer population alone.

The difference between enrollment and the stated primary-results population is not accompanied by a flow description. The record reports five enrolled and five patients completing four weeks, but does not provide participant-level details about screening, treatment exposure, or follow-up beyond the primary period. No imputation, sensitivity analysis, or other missing-data procedure is reported in the registry record.

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 0% reporting threshold.

The registry reports five participants at risk for serious adverse events, with zero affected. For other adverse events, it also reports five at risk and zero affected. The deaths field is zero, and no serious adverse-event terms are listed. These are the posted counts for the single treatment group over the reported four-week period.

Read these values as counts of participants recorded as affected in the listed categories, rather than as a detailed account of every event episode. The primary endpoint is framed as the number of participants with adverse events, but the registry fields available for the safety results separate serious events and other events. The record does not provide event narratives, severity grades, timing, or a fuller definition of the categories.

Zero recorded events among the participants in this short observation period does not establish zero risk. The study is small, has no control group, and reports the primary results for four-week completers. The safety figures describe those observations; they do not provide a comparative safety estimate or characterize longer-term treatment exposure. Numerical long-term safety findings are not reported in the registry record.

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

The posted result establishes that the registry records zero participants with serious adverse events and zero with other adverse events among the five patients reported as completing four weeks of therapy. It also records zero deaths. These values describe the short-term experience documented for this group under the study’s combination regimen.

The result does not establish that the regimen has no risk. A small number of observed participants and a limited observation period provide a narrow basis for describing event experience. No confidence interval is reported, and the registry provides no comparative group. The counts cannot show whether the event experience differs from what would have occurred without treatment or with another regimen.

The result also does not establish efficacy. The primary objective concerns feasibility of administration for a minimum of four weeks, assessed through adverse events. The registry lists other biological, pharmacokinetic, monitoring, and baseline-data objectives, but their numerical findings are not reported in the registry record. The available safety counts cannot answer those separate questions.

Nor do the four-week data establish the experience of participants receiving treatment for longer. The study description allows continuation for up to six months if treatment is tolerated, but results on treatment extension are not reported in the registry record. Conclusions should remain limited to the stated primary period and the participants included in the posted results.

In short, the findings are a descriptive feasibility observation from an open-label, single-group pilot. They are useful for understanding what the registry recorded in this small group, but they do not support a comparative or causal claim. The absence of an observed event in this record should not be interpreted as proof that adverse events cannot occur.

14. Why This Trial Matters Statistically

This trial is statistically notable because its question is framed as feasibility rather than comparative efficacy. In early studies, the practical question of whether a regimen can be administered and monitored can precede a larger evaluation. Here, the primary endpoint is the number of participants with adverse events during the four-week study, aligning the primary measure with the initial feasibility period.

The design also makes clear how much the interpretation depends on the study objective. A single-group pilot can record treatment experience, but it does not estimate a treatment contrast. The zero counts are meaningful as a description of the five reported completers, while the absence of a control group limits any broader inference about causes or comparative safety.

The registry’s secondary objectives show that feasibility involves more than an adverse-event count. The study also intended to examine toxicity monitoring, pharmacokinetics, a biological assay, and baseline measures for potential longer-term evaluation. However, without numerical results for these objectives in the registry record, the reader cannot use them to expand the interpretation of the posted primary findings.

This example also illustrates why the size and duration of a study matter when reading a zero count. A short period with few participants can document no recorded events while leaving substantial uncertainty about rarer events, longer exposure, or experience in a broader population. No interval estimate is reported to quantify that uncertainty.

Finally, the registry distinguishes a feasibility result from a claim of effectiveness. The trial’s descriptive outcomes and stated aims should not be treated as evidence of a comparative treatment effect. Keeping the inference aligned with the design is essential to a statistically sound reading.

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 primary limitation is the small reported population: five patients completed the four-week treatment period. This offers limited information about the range of possible experiences. The open-label, single-group design has no control arm, so it cannot separate treatment-associated observations from background events or other influences.

The primary results are restricted to the four-week period. Although the study description permits treatment continuation for up to six months if tolerated, numerical results for longer exposure are not reported in the registry record. The posted counts therefore do not characterize chronic toxicity or longer-term feasibility.

The safety fields provide counts of participants affected in serious and other adverse-event categories, along with a death count. Detailed event descriptions, severity grades, timing, and fuller event definitions are not reported in the registry record. The data are therefore limited for understanding the nature and clinical context of any safety observations.

The registry reports results for the five patients who completed four weeks, but does not provide a participant flow account or a description of how missing data were handled. It also does not report a detailed analysis plan, interim analyses, or the rationale for the enrollment target. The presence of illustrative sample-size assumptions does not establish a formal design justification for this single-group feasibility study.

Finally, the intervention is a three-drug combination. The design cannot isolate the contribution of zoledronic acid, pravastatin, or lonafarnib individually. The registry does not report numerical results for the secondary biological, pharmacokinetic, toxicity-monitoring, or baseline-data objectives, limiting interpretation of the study beyond the posted primary safety counts.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: A Study of Zoledronic Acid, Pravastatin, and Lonafarnib for Patients With Progeria — NCT00879034.
• Registry record last updated 2019-06-13; status last verified 2019-06.
• Results first posted 2017-07-31.
• 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.

19. Record Summary

NCT00879034 is a completed Phase II pilot study of zoledronic acid, pravastatin, and lonafarnib for patients with progeria. It was open label and single group, with five participants enrolled. Treatment was intended to begin for four weeks, with possible extension depending on tolerability. The primary objective was feasibility of administering the combination for at least four weeks, assessed through participant adverse-event counts.

Primary results are reported for five patients who completed four weeks. The registry lists zero participants affected by serious adverse events, zero affected by other adverse events, and zero deaths. There was no randomized comparison, and no analyses are listed in the reported analysis field. Numerical findings for the listed secondary objectives, longer-term treatment, and detailed statistical methods are not reported in the registry record.