Strategies and Treatments for Respiratory Infections &Amp; Viral Emergencies (STRIVE): Immune Modulation Strategy Trial: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Strategies and Treatments for Respiratory Infections &Amp; Viral Emergencies (STRIVE): Immune Modulation Strategy Trial (NCT05822583), a randomized phase 4 study. The primary outcome is Number of Participants Recovered by Day 60.

2. Clinical Question

The clinical question was whether early intensification of immune modulation with abatacept, alongside baseline immune modulation and standard care, was associated with a different recovery outcome than placebo alongside baseline immune modulation and standard care. The trial concerned hospitalized participants with COVID-19 who were receiving low-flow oxygen. The registry summary also describes additional immune modulation as part of standard care if disease progression or rapidly increasing oxygen requirements occurred.

The primary result is a comparison of the proportion recovered in each group, with a risk difference and confidence interval shown in the results. The posted proportions are close, and the interval is compatible with results on either side of no difference. That description concerns the registry data and does not establish a treatment effect.

The registry record describes the trial as randomized, double-masked, and parallel-group. It does not report details of the eligibility criteria beyond the population description in the summary, nor does it report the original statistical hypotheses or a formal plan for the primary analysis. Those details are important when assessing how broadly the result applies and how closely the posted calculation follows the intended analysis.

3. Trial Design

STRIVE is listed as a Phase 4, randomized, double-masked, parallel-group trial sponsored by the University of Minnesota. The registry reports enrollment of 285 and a completed status. The recorded study start date is 2023-07-06, and the primary completion date is 2025-06-21. The condition listed is COVID-19.

Participants were assigned to an active treatment group or a control group. The active group received an intravenous abatacept infusion with baseline immune modulation; the control group received an intravenous normal saline infusion with baseline immune modulation. The trial summary describes the study question as early intensification of immune modulation while participants were on low-flow oxygen. It also states that intensification of immunomodulation would be part of standard care for either group if signs of progression or rapidly increasing oxygen requirements occurred.

Randomization is intended to balance prognostic characteristics across groups on average, while masking is intended to limit the influence of treatment knowledge on care, assessment, or reporting. These are general design principles; the registry record does not describe the specific randomization procedure, who was masked, or how masking was maintained. It also does not report the original sample-size justification or the statistical analysis plan.

The primary outcome is recorded for 132 active-group participants and 137 control-group participants. Several secondary outcomes use group totals of 140 and 139, and the safety results also list 140 and 139 participants at risk. The registry record does not explain why these denominators differ. The enrollment total and the denominators in individual outcome entries should therefore be read in their own outcome context, rather than treated as interchangeable counts.

The registry record lists secondary outcomes for safety, a composite of death or CRIs, clinical progression or death, and sustained recovery. Results are posted for three secondary outcome comparisons. Separate analysis details for those secondary comparisons 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.

Overall Study

Reasons for not completing this period:

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

Population: Baseline characteristics are reported for the modified intent-to-treat cohort, which excluded 6 randomized participants who did not receive study infusion.

6. Primary Endpoint

The registry lists the primary outcome as Number of Participants Recovered by Day 60, measured over Through Day 60.

The primary endpoint is the number of participants recovered by Day 60. The registry describes recovery as assessed through Day 60 using the Days to Recovery Scale. In the posted results, this endpoint is expressed as a count of participants in each group, with the corresponding group denominator. The results section also presents a comparison of the recovery proportions as a risk difference.

A recovery endpoint is intended to capture a patient-centered outcome: whether participants have reached the registry’s defined state of recovery by the stated time. A fixed assessment horizon makes the outcome interpretable as a group comparison at that point, rather than as a summary of the full timing of recovery. This is a general explanation of endpoint design; the registry record does not describe the detailed criteria for classifying recovery, how assessments were scheduled, or how ambiguous or unavailable assessments were handled.

For the active group, 114 of 132 participants were reported as recovered by Day 60; for the control group, 118 of 137 were reported as recovered. The posted risk difference is 0.002, with a 95% confidence interval from -0.08 to 0.085. The interval communicates uncertainty around the difference in recovery proportions and includes values below and above zero.

The registry also lists a sustained recovery outcome through Day 60. That is a separate secondary measure and should not be substituted for the primary endpoint. Differences in endpoint definition and analysis population can affect interpretation; the registry record does not give a detailed account of how the sustained-recovery definition differs from the primary recovery measure.

7. Results Posted in the Registry

• Active Treatment Group: 86.4% (114/132) versus 86.1% (118/137) on control; risk difference 0.2 percentage points (95% CI -8.0 to 8.5), risk ratio 1.00 (0.91–1.10); unadjusted two-proportion z-test p = 0.956.

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.

Composite of Death or CRIs

• 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:
  • Active Treatment Group: 11.4% (16/140) versus 10.1% (14/139) on control; risk difference 1.4 percentage points (95% CI -5.9 to 8.6), risk ratio 1.13 (0.58–2.23); unadjusted two-proportion z-test p = 0.715.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Active Treatment Group and the control. The interval gives the range of effects that remain compatible with the data.

Number of Participants With Clinical Progression or Death Through Day 60

• 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:
  • Active Treatment Group: 9.3% (13/140) versus 12.9% (18/139) on control; risk difference -3.7 percentage points (95% CI -11.0 to 3.7), risk ratio 0.72 (0.37–1.41); unadjusted two-proportion z-test p = 0.330.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Active Treatment Group and the control. The interval gives the range of effects that remain compatible with the data.

Number of Participants With Sustained Recovery Through Day 60

• 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:
  • Active Treatment Group: 87.1% (122/140) versus 91.4% (127/139) on control; risk difference -4.2 percentage points (95% CI -11.5 to 3.0), risk ratio 0.95 (0.88–1.03); unadjusted two-proportion z-test p = 0.255.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Active Treatment Group and the control. The interval gives the range of effects that remain compatible with the data.

The secondary outcomes cover different aspects of the clinical course: a composite of death or CRIs through Day 120, clinical progression or death through Day 60, and sustained recovery through Day 60. These are related to the primary recovery question but are not identical outcomes. The primary endpoint asks whether participants were reported as recovered by Day 60; the secondary measures extend or alter the outcome definition, including events that reflect progression, death, or sustained status.

Across the posted secondary comparisons, the estimates point in mixed directions rather than forming a consistent pattern of advantage for one group across every measure. The intervals shown for these comparisons include no difference, and the posted unadjusted p-values do not give a substitute for examining the estimated effects and their uncertainty. The table is the place to review each endpoint’s counts and comparison; the broader point is that the secondary results do not provide a uniformly aligned signal that resolves the uncertainty in the primary result.

Secondary outcomes can add useful context by showing whether the primary finding is accompanied by a similar pattern in related outcomes. However, each outcome may have a different definition, time horizon, denominator, and susceptibility to missing or incomplete assessment. The registry record does not report detailed definitions for every secondary outcome or explain the different denominators, so those differences should not be interpreted as evidence of a particular data-handling process.

Unadjusted secondary results carry less weight as confirmatory evidence when the multiplicity strategy is not reported. Examining several outcomes creates more opportunities for apparently noteworthy results to arise by chance. A prespecified approach can describe how those comparisons should be interpreted, but that approach is not reported in the registry record. The results therefore offer descriptive context and should not be treated as independent proof of effects on each outcome.

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

• Safety Outcome Through Day 28
• Composite of Death or CRIs
• Number of Participants With Clinical Progression or Death Through Day 60
• Number of Participants With Sustained Recovery Through Day 60

9. Statistical Interpretation

10. Statistical Methods Explained

The registry presents the primary outcome as counts of participants recovered by Day 60, together with group denominators and a risk-difference comparison. It also posts a confidence interval and an unadjusted p-value for that comparison. The analysis methods used for the sponsor’s intended primary analysis are not reported in the registry record, so the explanation concerns how to read the posted quantities, not a reconstruction of the protocol analysis.

What does a risk difference represent?

A risk difference compares the proportion with an outcome in one group with the proportion in another group. For the primary outcome, the active group’s posted proportion is 0.864 and the control group’s posted proportion is 0.861. The posted risk difference is 0.002. The sign gives the direction under the ordering used in the comparison: a positive difference indicates a higher proportion in the active group, and a negative difference indicates a higher proportion in the control group. The difference is on the proportion scale, which makes it an absolute comparison rather than a relative one.

Risk differences are often useful because they describe the size of a group contrast in the same units as the outcome proportions. They do not, by themselves, account for other participant characteristics or features of the trial design. The registry record does not report an adjusted primary estimate, so the posted comparison should not be described as adjusted for covariates.

How should the confidence interval be read?

A confidence interval is a range of values produced by a statistical procedure intended to reflect uncertainty in an estimate. In general, a narrower interval indicates greater precision, while a wider interval indicates less precision. The primary risk-difference interval is -0.08 to 0.085. It spans zero and includes both negative and positive differences. That means the registry result does not precisely determine which direction the underlying difference might take or how large it might be within the interval. A confidence interval is not a range containing every plausible individual outcome, and it is not a direct probability statement that a particular value is true.

What does the p-value add?

The posted unadjusted p-value for the primary comparison is 0.956. In general, a p-value summarizes the compatibility of the observed data with a null hypothesis under a specified statistical model and calculation. It is not a measure of the probability that the treatment has no effect, and it does not describe the clinical importance of a result. The p-value and confidence interval address related aspects of uncertainty, but the interval gives a range of effect sizes and directions rather than a single summary of compatibility. The registry record does not report the planned significance threshold or the exact test used for the primary analysis.

Why does the distinction between unadjusted and adjusted matter?

An unadjusted comparison uses the posted group summaries without accounting for additional covariates in a regression or other adjusted model. In a randomized trial, randomization is intended to support a fair comparison, but adjustment may still be part of a prespecified analysis plan. The record does not report whether adjustment was planned or whether the displayed result is the sponsor’s intended primary analysis. It would therefore be inappropriate to infer a particular model or claim that the result is adjusted.

The secondary comparison results are also shown without adjusted analyses reported. When multiple outcomes are examined, the chance of observing an apparently notable result by chance can increase. A multiplicity plan may control or otherwise address that issue, but no such strategy is reported. This is why secondary p-values and intervals should not be treated as if each were an isolated, prespecified confirmatory test.

What is the role of the event counts?

The primary counts are 114 recovered participants in the active group and 118 in the control group. Counts are the observed number meeting the endpoint definition among the participants listed for that outcome. A count alone does not provide the comparison without its denominator: the same count can represent different proportions in groups of different sizes. The registry posts denominators of 132 and 137 for this endpoint. For several secondary outcomes, it lists denominators of 140 and 139. The reason for those differences is not reported in the registry record.

For binary outcomes, the registry also displays relative measures in the comparison results, including risk ratios and odds ratios. A risk ratio compares proportions as a ratio; an odds ratio compares the odds of the outcome. These measures answer different questions from the risk difference, and their values should be interpreted with their own confidence intervals. The primary interpretation emphasizes the risk difference and its interval because that is the posted absolute comparison. The registry record does not explain whether a particular measure was selected as the primary analysis measure in the original plan.

What cannot be recovered from the registry entry?

The statistical plan, analysis population, missing-data methods, handling of protocol deviations, and details of the primary model are not reported in the registry record. Nor are interim analyses or the trial’s original sample-size justification reported. These are not details that can be inferred from the endpoint counts or the p-value. Without them, readers can describe the displayed comparisons, but cannot establish from the registry entry alone whether every planned analysis was completed or how the posted calculations relate to the full protocol.

11. Confidence Intervals and Precision

The primary risk-difference estimate is 0.002, and its 95% confidence interval extends from -0.08 to 0.085. The interval is compatible with a negative difference, a difference close to zero, and a positive difference. Its inclusion of zero means the displayed data do not exclude no difference under this interval procedure. Its reach on either side also indicates that the estimate is not precise enough to identify a narrow range of possible group differences.

Precision is about the range of values consistent with the data under the statistical method, not about whether an outcome is important. A confidence interval that includes zero does not prove that the groups are identical. Conversely, the point estimate near zero does not establish equivalence. A formal equivalence conclusion would require an appropriate design and a prespecified margin; such a margin is not reported in the registry record.

The primary outcome denominators are 132 in the active group and 137 in the control group. These denominators provide context for the uncertainty, but the registry record does not report a precision target or explain the original sample-size rationale. It therefore cannot be determined from the posted results whether the trial was designed to estimate this difference with a particular degree of precision.

The secondary intervals also span zero. They vary in width, which reflects differing event counts and estimates as well as the statistical calculations used. The results should be read with the interval alongside the point estimate rather than by focusing on a p-value alone. The registry record does not report adjusted intervals or a multiplicity correction, so the posted intervals do not by themselves address uncertainty from examining multiple outcomes.

Confidence intervals describe uncertainty in group-level estimates, not the range of individual responses. They also do not address potential bias from missing data, outcome classification, or analysis choices. Those details are not reported in the registry record, so the intervals should be understood as precision summaries for the posted comparisons rather than complete measures of every source of uncertainty.

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 sample-size section is a planning illustration based on the observed effect in the posted results, not a report of the trial’s original design calculation. For these binary outcomes, its entries are participants per arm, not total events. The illustration assumes a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. It uses the stated fraction of the observed effect as the effect to detect. The trial’s original sample-size assumptions are not reported in the registry record.

The 80% power column gives the estimated participants per arm for a future planning scenario that would have 80% power under those assumptions. The 90% power column gives the corresponding participants per arm for a scenario with 90% power. In plain terms, power is the chance of detecting an effect of the specified size under the assumed model and design if that effect is the true one. It is not a guarantee that a future study will detect an effect, and it depends on the assumptions used.

The table includes planning for 100% of the observed effect, 75% of the observed effect, and 50% of the observed effect. The entries become larger when planning to detect a smaller fraction of the observed effect: smaller effects generally require more participants to distinguish them from random variation under otherwise similar assumptions. The table and accompanying plot should be read as hypothetical planning aids, not as a description of the enrollment achieved in this trial.

This is not observed power. The registry lists enrollment of 285, while the illustration uses modeled planning assumptions and the observed effect rather than the trial’s original design assumptions. The planning figures do not change the interpretation of the posted confidence interval or establish that the study was adequately or inadequately sized.

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, p₀ and p₁ are the control and treatment proportions, and p̄ is their average.

Worked calculation for this trial

1. Control proportion p₀ = 0.861; treatment proportion p₁ = 0.864; average p̄ = 0.862.
2. First term: z_1−α/2 × √[2p̄(1−p̄)] = 1.96 × 0.4871 = 0.9546.
3. Second term: z_1−β × √[p₀(1−p₀) + p₁(1−p₁)] = 0.842 × 0.4871 = 0.4099.
4. n = (0.9546 + 0.4099)² / (0.0023)² = 345,187.0, rounded up to 345,188 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
p0 <- 0.861313868613139                          # control proportion
p1 <- 0.863636363636364                          # treatment proportion
n_per_arm <- function(power, frac = 1) {
  q1 <- p0 + (p1 - p0) * frac               # smaller effect = fraction of the observed difference
  pbar <- (p0 + q1) / 2
  z_b <- qnorm(power)
  ceiling(round((z_a * sqrt(2 * pbar * (1 - pbar)) + z_b * sqrt(p0 * (1 - p0) + q1 * (1 - q1)))^2 / (q1 - p0)^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 (unrounded n per arm)
cat("power.prop.test:", round(power.prop.test(p1 = p0, p2 = p1, power = 0.80)$n, 1), "\n")

# Simulation: how often does the z-test reject at the 80%-power sample size?
set.seed(5822583)
n    <- n_per_arm(0.80)
reps <- 20000
x0 <- rbinom(reps, n, p0); x1 <- rbinom(reps, n, p1)
ph <- (x0 + x1) / (2 * n)
z  <- ((x1 - x0) / n) / sqrt(ph * (1 - ph) * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(z) > z_a, na.rm = TRUE), reps))

Output from running the code

100% of observed effect: n per arm = 345,188 (80% power), 462,107 (90% power)
 75% of observed effect: n per arm = 614,756 (80% power), 822,983 (90% power)
 50% of observed effect: n per arm = 1,385,648 (80% power), 1,854,989 (90% power)
power.prop.test: 345187 
Simulated power at n = 345,188 per arm: 0.796 (20000 replicates)

The simulation draws many pairs of event counts at the planned sample size and counts how often the two-proportion z-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

The registry record does not report a multiplicity strategy for the primary and secondary outcomes. Multiplicity refers, in general, to the statistical issue that arises when several hypotheses or outcomes are examined: without an appropriate plan, the overall chance of false-positive findings may be higher than for a single test. A plan might specify which outcome is primary, how secondary outcomes are ordered, or whether adjustments are used. No such details are reported, and the posted secondary comparisons are not identified as multiplicity-adjusted.

The record lists the primary outcome and several secondary outcomes, but it does not report the full statistical analysis plan or the prespecified analysis population. It is therefore not possible to determine from the registry entry which participants were intended to be included in each analysis, whether an intention-to-treat approach was specified, or how deviations from assigned treatment were handled. These are important distinctions for interpreting randomized trial results.

Missing-data methods are not reported in the registry record. The entry does not explain how participants without a Day 60 assessment were handled, whether any outcomes were imputed, or whether sensitivity analyses were conducted. The available endpoint counts and denominators do not reveal the reasons for unavailable data. In particular, the primary denominator differs from the denominators shown for several secondary outcomes and safety; the registry record does not explain this difference. It should not be attributed to a specific cause without further information.

The record also does not report interim analyses, stopping rules, or the original sample-size justification. These omissions do not demonstrate that such procedures were or were not used; they mean the registry record does not document them. Likewise, no adjusted primary analysis or sensitivity analysis is listed in the posted results.

These gaps limit assessment of the inferential framework and the robustness of the posted comparisons. They do not prevent readers from describing the counts, estimates, confidence intervals, and p-values shown. They do mean that conclusions about prespecification, analysis-population choices, missingness, and control of false-positive findings cannot be established from this record alone.

15. 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.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: acute respiratory failure (3.6%), copd (2.2%), pneumonia bacterial (1.4%), pneumonia viral (1.4%), leukocytosis (0.7%).

The safety entry reports serious adverse events among 140 participants at risk in the active treatment group and 139 in the control group. Serious adverse events affected 15 active-group participants and 17 control-group participants. The entry separately reports other adverse events affecting 18 participants in the active group and 21 in the control group. No deaths are listed in either group in this safety summary.

These figures are counts of participants affected, not counts of every event episode. The registry record does not provide a comparison estimate or confidence interval for these safety counts, nor does it report an attribution assessment linking events to treatment. The group counts should therefore be read descriptively and not as evidence that one treatment caused or prevented an event.

The listed serious-event terms include acute respiratory failure at 3.6%, COPD at 2.2%, bacterial pneumonia at 1.4%, viral pneumonia at 1.4%, leukocytosis at 0.7%, and hepatic failure at 0.7%. The registry entry does not specify a group assignment for these listed percentages in the information, so they should not be attributed to a particular arm.

Safety counts may be influenced by how events were defined, collected, coded, and followed. Detailed definitions and comparative safety analyses are not reported in the registry record. These data describe the posted safety summary and are not a complete basis for judging clinical safety.

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

The registry results show that recovery by Day 60 was reported for 114 of 132 participants in the active treatment group and 118 of 137 participants in the control group. The posted risk difference is 0.002, with a 95% confidence interval from -0.08 to 0.085 and an unadjusted p-value of 0.956. These figures describe the observed outcome counts and the uncertainty around the displayed comparison.

The interval includes zero and extends in both directions. The findings therefore do not establish a precise difference between the groups, but they also do not prove that the groups are equivalent. The registry record does not report a prespecified equivalence or noninferiority margin. A small point estimate alone cannot settle whether meaningful differences remain compatible with the data.

The result should be understood within the trial as registered: a randomized, double-masked, parallel-group study of abatacept plus baseline immune modulation compared with placebo plus baseline immune modulation, with standard care described for both groups. The record does not report detailed eligibility criteria, the analysis plan, missing-data handling, or adjustment methods. Those gaps limit how fully the posted result can be evaluated and how confidently it can be generalized beyond the people and care context represented in the trial.

The secondary results add context but do not remove the primary uncertainty. They cover different outcomes and time horizons, point in mixed directions, and are presented without a reported multiplicity adjustment. They should not be treated as a single confirmatory body of evidence.

This page is a statistical reading of the registry record, not medical advice and not a recommendation about treatment. It does not establish that abatacept improves, worsens, or has no effect on recovery. It describes what the posted data show, how uncertain the comparison is, and which analytic details are not documented in the registry record.

17. Why This Trial Matters Statistically

This trial is statistically instructive because the primary point estimate is close to zero while its confidence interval spans meaningful differences in both directions. That contrast illustrates why a point estimate and its uncertainty need to be read together. A near-zero estimate does not demonstrate equivalence, and a confidence interval that includes zero does not prove the absence of an effect.

The endpoint is also a useful example of the distinction between a count and a comparative estimate. The registry reports recovered-participant counts along with denominators, then presents a risk difference and confidence interval. A reader can see the observed group outcomes while also assessing the uncertainty in the group contrast. The different denominators shown for the primary, secondary, and safety entries highlight why each result must be interpreted with its own population count.

Another statistical issue is how multiple outcomes are interpreted. Recovery, sustained recovery, progression, death, and the composite outcome capture related but distinct aspects of the clinical course. Their mixed directions do not create a simple overall answer, particularly when the registry does not report a multiplicity plan or adjusted secondary analyses.

Finally, the sample-size section shows the difference between a planning illustration based on an observed effect and the design rationale for the completed trial. The illustration uses stated assumptions and is not evidence of the trial’s original design or of observed power. The original sample-size justification is not reported in the registry record. Keeping these distinctions clear helps prevent a post hoc planning calculation from being mistaken for a prospective design feature.

18. 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.

Several trial-specific limitations in the registry record constrain interpretation. The primary recovery result uses denominators of 132 and 137, whereas secondary outcomes and safety use denominators of 140 and 139. The reason for this variation is not reported in the registry record, and no explanation for the outcome-specific analysis populations is available.

The record does not report the detailed recovery criteria beyond reference to the Days to Recovery Scale, nor does it describe how missing or incomplete assessments were handled. The original statistical analysis plan, primary model, analysis population, and sample-size justification are also not reported. Without those details, it is not possible to verify whether the posted comparisons correspond to the intended protocol analysis.

The registry presents several secondary outcomes, but does not report a multiplicity strategy or adjusted analyses. This makes the secondary results less suitable for standalone confirmatory interpretation. The secondary outcome definitions are not described in detail here, and the entry does not explain why the composite outcome is reported through Day 120 while other outcomes are reported through Day 60.

The safety summary gives counts of participants affected and selected serious adverse-event terms, but does not provide comparative uncertainty estimates or event attribution. The listed terms are not assigned to a specific arm in the posted information used for this page. Safety interpretation is consequently limited to descriptive reporting.

The registry record also does not describe the specific randomization procedure, who was masked, interim analyses, or stopping rules. These omissions are limits of the available record; they do not show that such procedures were absent. The results should be interpreted as registry-posted summaries rather than a complete account of the trial protocol and analysis.

19. Related Tutorials

20. Related Statistical Calculators

21. Sources

• ClinicalTrials.gov: Strategies and Treatments for Respiratory Infections &Amp; Viral Emergencies (STRIVE): Immune Modulation Strategy Trial — NCT05822583.
• Registry record last updated 2026-08-31; status last verified 2026-08.
• Results first posted 2026-08-31.
• 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.

22. Record Summary

STRIVE is listed as a Phase 4 randomized, double-masked, parallel-group trial sponsored by the University of Minnesota. It enrolled 285 participants with COVID-19 and has a completed status. The recorded study start date is 2023-07-06, and the primary completion date is 2025-06-21.

The trial compared intravenous abatacept plus baseline immune modulation with normal saline placebo plus baseline immune modulation, alongside standard care. Its primary outcome was the number of participants recovered by Day 60, assessed using the Days to Recovery Scale. The posted recovery counts were 114 of 132 in the active group and 118 of 137 in the control group. The risk difference was 0.002, with a 95% confidence interval from -0.08 to 0.085.

The registry also lists secondary clinical and safety outcomes. The analysis plan, missing-data methods, multiplicity strategy, and original sample-size justification are not reported in the registry record. The posted results can be described, but the record does not contain all details needed to evaluate the full prespecified analysis.