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 AZD7442 - a Potential Combination Therapy for the Prevention and Treatment of COVID-19 (NCT04507256), a randomized phase 1 study. The primary outcome is Number of Participants With Adverse Events (AEs) and Serious AEs.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04507256 |
| Phase | Phase 1 |
| Condition | COVID-19 |
| Allocation | Randomized |
| Design model | Sequential |
| Masking | Double |
| Enrollment | 60 |
| Arms in the primary outcome | n/a |
| Lead sponsor | AstraZeneca |
| Results posted | Yes |
2. Clinical Question
Population
Healthy adults 18 to 55 years of age were eligible for the safety evaluation described in the registry record. The record states an enrollment of 60. The safety analysis set is defined as participants who were randomized and received any amount of AZD7442.
Intervention
AZD7442, a combination product of AZD8895 and AZD1061, was evaluated at different doses and by different administration routes. The recorded active groups include AZD7442 300 mg by intramuscular injection, AZD7442 300 mg by intravenous infusion, AZD7442 1000 mg by intravenous infusion, AZD7442 3000 mg by intravenous infusion, and AZD7442 3000 mg intravenously co-administered.
Comparator
Pooled placebo is the comparator group in the adverse-event results. The intervention description states that placebo was administered across fixed-dose cohorts similar to active treatment. The record does not report a single prespecified active-versus-placebo contrast for the primary outcome.
Primary question
The study evaluated the safety and tolerability of AZD7442 administered intravenously or intramuscularly, with adverse events and serious adverse events recorded from screening day (Day -28) until the follow-up/end of treatment visit (Day 361). It also evaluated pharmacokinetics, including serum concentration and clearance measures.
3. Trial Design
This was a Phase I, randomized, double-blind, placebo-controlled study with a sequential model. The official title describes a study of safety, tolerability and pharmacokinetics in healthy adults. The registry lists COVID-19 as the condition and frames AZD7442 as a potential combination therapy for prevention and treatment, while the brief summary describes this first-in-humans dose-escalation study as intended to enable future efficacy studies.
The record reports an enrollment of 60 and describes five fixed-dose cohorts for AZD7442, using intravenous infusions and direct gluteal intramuscular injections. It also describes one cohort receiving co-administration of AZD8895 and AZD1061 mixed into a single infusion. The placebo description says placebo was administered across five fixed-dose cohorts similar to active treatment. The arm descriptions include pooled placebo and the active dose-route groups listed in the adverse-event results.
The study status is completed. The record gives a start date of 2020-08-18 and a primary completion date of 2021-10-19. These dates describe the registry record; they do not establish when particular participants were followed or when individual events occurred.
The main focus was not a clinical efficacy comparison. The primary outcome concerns the number of participants with adverse events and serious adverse events. Secondary outcomes include pharmacokinetic measures such as maximum serum concentration, time to maximum concentration, terminal elimination half-life, area under the concentration curve, and clearance. The registry record does not report a detailed statistical analysis plan or explain how the sequential dose escalation governed decisions between cohorts.
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: Participants who met the inclusion and none of the exclusion criteria were enrolled to the study. A washout period was not included in this study.
Overall Study
| Stage | Pooled Placebo | AZD7442 300 mg, IM | AZD7442 300 mg, IV | AZD7442 1000 mg, IV | AZD7442 3000 mg, IV | AZD7442 3000 mg, IV Co-administered |
|---|---|---|---|---|---|---|
| STARTED | 10 | 10 | 10 | 10 | 10 | 10 |
| COMPLETED | 9 | 10 | 10 | 9 | 10 | 10 |
| NOT COMPLETED | 1 | 0 | 0 | 1 | 0 | 0 |
Reasons for not completing this period:
| Reason | Pooled Placebo | AZD7442 300 mg, IM | AZD7442 300 mg, IV | AZD7442 1000 mg, IV | AZD7442 3000 mg, IV | AZD7442 3000 mg, IV Co-administered |
|---|---|---|---|---|---|---|
| Withdrawal by Subject | 1 | 0 | 0 | 1 | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: Safety analysis set included all participants who were randomized and received any amount of AZD7442.
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: The randomized set consisted of all participants randomized into the study.
Only the first 6 of 7 groups are shown.
| Characteristic | Unit | Pooled Placebo | AZD7442 300 mg, IM | AZD7442 300 mg, IV | AZD7442 1000 mg, IV | AZD7442 3000 mg, IV | AZD7442 3000 mg, IV Co-administered |
|---|---|---|---|---|---|---|---|
| Participants analysed | 10 | 10 | 10 | 10 | 10 | 10 | |
| Age, Continuous | Years | 38.1 (SD 11.45) | 41.9 (SD 6.51) | 40.7 (SD 7.83) | 38.9 (SD 8.86) | 35.8 (SD 9.44) | 39.6 (SD 9.30) |
| Sex: Female, Male: Female | Participants | 5 | 2 | 6 | 3 | 3 | 4 |
| Sex: Female, Male: Male | Participants | 5 | 8 | 4 | 7 | 7 | 6 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 0 | 1 | 0 | 0 | 0 | 0 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 10 | 9 | 10 | 10 | 10 | 10 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 2 | 2 | 2 | 0 | 3 | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 1 | 1 | 1 | 1 | 0 | 1 |
| Race (NIH/OMB): White | Participants | 6 | 6 | 7 | 8 | 6 | 7 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 1 | 1 | 0 | 1 | 1 | 2 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Participants With Adverse Events (AEs) and Serious AEs, measured over From screening day (Day -28) until Follow-up/end of treatment visit (Day 361).
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the number of participants with adverse events and serious adverse events. Its timeframe runs from screening day (Day -28) until the follow-up/end of treatment visit (Day 361). The endpoint is recorded as a count of participants, rather than as a continuous measurement such as a concentration or a time-to-event measure.
Safety and tolerability are central questions in an early-phase study. Adverse-event counts can describe how many participants experienced events during the stated follow-up, while serious adverse-event counts separately describe events classified as serious in the registry results. These counts are useful for characterizing observed events and identifying issues that warrant attention in subsequent research. They do not, by themselves, establish that an event was caused by the study treatment.
The posted results distinguish serious adverse events from other adverse events. They also report deaths. These are separate count summaries and should not be treated as interchangeable measures. The registry record does not provide detailed event descriptions for the other adverse-event counts or a breakdown by event term in the registry record reported for this endpoint. It also does not report a formal hypothesis test or adjusted treatment-effect estimate for the endpoint.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The serious adverse-event count is zero in each recorded group: pooled placebo, AZD7442 300 mg intramuscularly, AZD7442 300 mg intravenously, AZD7442 1000 mg intravenously, AZD7442 3000 mg intravenously, and AZD7442 3000 mg intravenously co-administered. The death count is also zero in every group. These statements describe the event counts recorded during the endpoint timeframe; they do not show that the underlying risk is zero.
The separate count for other adverse events varies across the groups. The registry reports 8 for pooled placebo, 2 for AZD7442 300 mg intramuscularly, 5 for AZD7442 300 mg intravenously, 6 for AZD7442 1000 mg intravenously, 7 for AZD7442 3000 mg intravenously, and 6 for AZD7442 3000 mg intravenously co-administered. These are counts, not percentages, and the record does not give event terms or a treatment-effect estimate for these differences.
Because the groups are small, the counts alone provide limited precision for comparing event frequencies. A count of zero means no event of that category was recorded in the group during the stated observation period; it does not prove that an event could not occur. Likewise, differences in raw counts do not establish a causal effect of dose, route, or treatment. Interpretation depends on the design, ascertainment, population, follow-up, and analysis, and several of those details are not reported in the registry record.
The study was designed as a first-in-humans dose-escalation safety and pharmacokinetic evaluation. Its purpose, as described in the registry record, was to support future studies of efficacy in preventing and treating COVID-19. The posted safety counts therefore address observed adverse events in this study, not whether AZD7442 prevents or treats COVID-19. The record does not report efficacy results, and no efficacy conclusion follows from the safety counts.
The primary endpoint combines adverse-event and serious-adverse-event reporting, but the available result information does not give a single prespecified comparison or an inferential result for that endpoint. The registry record also does not report confidence intervals for the group counts. Without those intervals or a stated comparative analysis, the precision of differences between groups cannot be assessed from the counts alone.
9. Statistical Methods Explained
What does a participant count represent?
The endpoint reports the number of participants with events, rather than the total number of event episodes. In general, a participant count describes how many people met the endpoint definition during follow-up. It does not indicate how many times an event occurred, how long it lasted, or how severe each non-serious event was. The registry record labels the endpoint as a count of participants and reports serious adverse events, other adverse events, and deaths separately.
Why separate serious and other adverse events?
In general, categorizing adverse events by seriousness helps distinguish different types of safety information. A serious-event count is not a measure of all symptoms or events, and the separate count for other events should not be read as a count of serious events. The registry record provides no event-term details for the other adverse-event counts in the registry record. The classifications and counts describe what was recorded, not whether an event was caused by treatment.
How should the group counts be compared?
General statistical interpretation of a binary outcome starts with a clear definition of the event and the group being compared. A count alone is not a rate unless its denominator and observation period are also considered. The posted group information gives 10 at risk for serious events and 10 at risk for other events in each group. The endpoint timeframe is stated as screening day (Day -28) to the follow-up/end of treatment visit (Day 361). The record does not report confidence intervals or a formal comparative estimate for the safety counts.
In general, a confidence interval communicates the range of effect values compatible with the observed data under the chosen statistical method. It helps convey uncertainty beyond a point estimate. No confidence interval for these safety comparisons is reported in the registry record, so the precision of a difference between groups cannot be read from the event counts alone. With sparse outcomes, including zero counts, statistical estimates can be especially uncertain; general methods for such data must be chosen carefully and should be specified rather than inferred.
What does randomization contribute?
In general, random allocation aims to make treatment groups comparable with respect to measured and unmeasured characteristics, on average. Double masking is intended to reduce the influence of treatment knowledge on care or assessment. These design features do not remove uncertainty, guarantee balance in a small study, or establish that an observed event was treatment-related. The registry record lists randomized allocation and double masking, but does not report details about implementation, concealment, or the success of masking.
What can planning calculations tell the reader?
The stated sample-size assumptions describe planning illustrations based on the observed effect, using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The effect to detect is expressed as a stated fraction of the observed effect. These calculations are planning illustrations, not observed power and not evidence that a treatment effect exists. The record does not report a trial-specific sample-size justification, and the registry entries do not provide calculated planning values to interpret. The primary outcome is also not reduced to one comparison because it has several categories or time points.
In general, sample-size calculations depend on the outcome, expected effect, variability or event frequency, allocation, and analysis method. A planning estimate should not be confused with the number actually enrolled or treated, nor with the precision of the final results. For a binary endpoint, the assumptions used for an illustration may not reflect the observed event pattern in a small early-phase study.
What is not available about the analysis?
The registry record does not report a detailed statistical analysis plan for the primary safety endpoint, a method for handling missing outcomes, or a strategy for adjusting comparisons for multiplicity. The number of outcome measures is listed as 11 and the number of analyses as 2, but those counts do not by themselves define which tests were conducted or how any results were interpreted. The record also does not report interim-analysis methods. None of these unreported methods should be inferred from the study design or the posted counts.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 11 outcome measures and 2 analyses. Secondary outcomes include multiple pharmacokinetic measures, among them maximum serum concentration, time to maximum concentration, terminal elimination half-life, area under the concentration curves, and clearance. When several outcomes or comparisons are considered, multiplicity can increase the chance of obtaining at least one apparently notable result by chance. General approaches include prespecifying a primary comparison or adjusting inference across a defined family of tests. The multiplicity strategy is not reported in the registry record.
The primary outcome has several categories or time points and is not reduced to one comparison in the posted analysis information. The record does not report which comparisons were prespecified, whether any adjustment was used, or how interpretation across safety and pharmacokinetic outcomes was organized. A count of analyses does not supply those details.
The safety analysis set is defined as all participants who were randomized and received any amount of AZD7442. The registry record does not report how missing adverse-event information was handled, whether follow-up was complete for each participant, or whether any participants were excluded from particular endpoint summaries. The record also does not provide details of analysis populations for the pharmacokinetic outcomes.
These omissions matter because missing follow-up or differing analysis populations can affect what an event count represents. They also limit assessment of whether comparisons follow the randomized groups or another analysis set. The registry record does not report an imputation method, sensitivity analysis, or detailed analysis-population rules.
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 |
|---|---|---|---|
| Pooled Placebo | 0 | 10 | 0.0% |
| AZD7442 300 mg, IM | 0 | 10 | 0.0% |
| AZD7442 300 mg, IV | 0 | 10 | 0.0% |
| AZD7442 1000 mg, IV | 0 | 10 | 0.0% |
| AZD7442 3000 mg, IV | 0 | 10 | 0.0% |
| AZD7442 3000 mg, IV Co-administered | 0 | 10 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Pooled Placebo | 0 of 10 |
| AZD7442 300 mg, IM | 0 of 10 |
| AZD7442 300 mg, IV | 0 of 10 |
| AZD7442 1000 mg, IV | 0 of 10 |
| AZD7442 3000 mg, IV | 0 of 10 |
| AZD7442 3000 mg, IV Co-administered | 0 of 10 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Pooled Placebo | 8 of 10 |
| AZD7442 300 mg, IM | 2 of 10 |
| AZD7442 300 mg, IV | 5 of 10 |
| AZD7442 1000 mg, IV | 6 of 10 |
| AZD7442 3000 mg, IV | 7 of 10 |
| AZD7442 3000 mg, IV Co-administered | 6 of 10 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Pooled Placebo | AZD7442 300 mg, IM | AZD7442 300 mg, IV | AZD7442 1000 mg, IV | AZD7442 3000 mg, IV | AZD7442 3000 mg, IV Co-administered |
|---|---|---|---|---|---|---|---|
| Headache | Nervous system disorders | 2 of 10 | 0 of 10 | 2 of 10 | 2 of 10 | 3 of 10 | 0 of 10 |
| Back pain | Musculoskeletal and connective tissue disorders | 1 of 10 | 0 of 10 | 0 of 10 | 1 of 10 | 1 of 10 | 1 of 10 |
| Diarrhoea | Gastrointestinal disorders | 0 of 10 | 0 of 10 | 1 of 10 | 1 of 10 | 0 of 10 | 1 of 10 |
| Fatigue | General disorders | 0 of 10 | 0 of 10 | 0 of 10 | 1 of 10 | 0 of 10 | 2 of 10 |
| Abdominal distension | Gastrointestinal disorders | 0 of 10 | 0 of 10 | 2 of 10 | 0 of 10 | 0 of 10 | 0 of 10 |
| Abdominal pain | Gastrointestinal disorders | 0 of 10 | 0 of 10 | 2 of 10 | 0 of 10 | 0 of 10 | 0 of 10 |
| Toothache | Gastrointestinal disorders | 0 of 10 | 0 of 10 | 0 of 10 | 2 of 10 | 0 of 10 | 0 of 10 |
| Nasopharyngitis | Infections and infestations | 0 of 10 | 1 of 10 | 0 of 10 | 1 of 10 | 0 of 10 | 0 of 10 |
| Urinary tract infection | Infections and infestations | 1 of 10 | 0 of 10 | 1 of 10 | 0 of 10 | 0 of 10 | 0 of 10 |
| Myalgia | Musculoskeletal and connective tissue disorders | 0 of 10 | 0 of 10 | 0 of 10 | 1 of 10 | 1 of 10 | 0 of 10 |
The serious adverse-event counts are reported as zero in pooled placebo and in each of the five AZD7442 groups: 300 mg intramuscularly, 300 mg intravenously, 1000 mg intravenously, 3000 mg intravenously, and 3000 mg intravenously co-administered. The death count is zero in each of these groups. The group information reports 10 at risk for serious events.
A zero count means no serious adverse event or death was recorded in the group during the endpoint timeframe in the registry results. It does not establish the absence of risk beyond this study, its population, or its follow-up. The record reports other adverse-event counts separately, with 10 at risk for other events in each group. Those counts range from 2 to 8 across the listed groups, as recorded in the registry.
These are descriptive counts. They do not establish treatment causation, and the registry record does not provide event-term details or a formal statistical comparison for these safety results. The study involved healthy adults 18 to 55 years of age, so the results should be understood within that stated study population rather than generalized automatically to other populations.
12. What the Result Does, and Does Not, Mean
The registry results provide a descriptive account of adverse-event counts during a Phase I study of AZD7442 in healthy adults. They report no serious adverse events and no deaths in any recorded group, alongside separate counts for other adverse events. The results are relevant to the study's stated safety and tolerability evaluation, but they do not establish that AZD7442 is free of risk.
The count pattern is not, on its own, a causal comparison. Randomization and double masking are features of the study design, but the registry information does not report an adjusted effect estimate, confidence interval, or formal test for the adverse-event comparisons. Nor does it provide event-level detail for the other adverse events. Differences in the reported counts should therefore be read descriptively rather than as proof that a dose or route caused more or fewer events.
The study also evaluated pharmacokinetics, with secondary outcomes covering serum concentration and clearance measures. Those outcomes concern how the study product is present and processed in the body; they are not direct measures of prevention or treatment of COVID-19. The brief summary says the study was intended to enable future efficacy studies. The registry record does not report efficacy results from this study.
Overall, the posted data characterize safety events recorded in this early-phase setting. They do not answer whether AZD7442 prevents COVID-19, treats COVID-19, or changes outcomes in populations beyond the stated healthy adult participants. Those questions require evidence designed to assess clinical efficacy and are not resolved by these safety counts.
13. Why This Trial Matters Statistically
This trial illustrates why early-phase research and efficacy trials answer different statistical questions. The registry describes a first-in-humans dose-escalation study focused on safety, tolerability and pharmacokinetics. Its adverse-event counts summarize what was recorded during follow-up, while its pharmacokinetic outcomes characterize concentration and clearance. Neither type of outcome is itself a measure of COVID-19 prevention or treatment benefit.
It also demonstrates the importance of separating a count from a comparative estimate. A zero serious-event count is a useful description of the observed data, but it does not mean the underlying event risk is zero. Counts across groups are not, by themselves, evidence of a causal dose or route effect. Understanding precision requires inferential information such as confidence intervals, which are not reported in the registry record.
The study's randomized, double-blind, placebo-controlled design is relevant to how its comparisons were structured. At the same time, small group-level event counts and missing details about the statistical analysis limit what can be concluded from the posted results. The record does not report multiplicity procedures, missing-data methods, or a detailed analysis plan.
Finally, the registry states that the study was intended to enable future efficacy studies. Keeping that purpose distinct from the observed safety and pharmacokinetic outcomes helps prevent a common interpretive error: treating an early-phase safety profile as evidence of clinical efficacy.
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 registry record gives group-level adverse-event counts but does not report the event terms underlying the other adverse-event counts. It therefore does not allow assessment of which events occurred, their severity beyond the serious-event classification, their timing, or whether the same participant experienced more than one event. The reported endpoint is a count of participants, not a full event history.
The serious adverse-event and death counts are zero in all recorded groups, but zero observed events do not demonstrate zero underlying risk. The group information reports 10 at risk for each event category in each group, and the stated follow-up extends from screening day (Day -28) until the follow-up/end of treatment visit (Day 361). The record does not provide confidence intervals for these counts or a formal comparison of groups.
The population is described as healthy adults 18 to 55 years of age. This limits the population directly characterized by the safety results. The study is Phase I and intended to support future efficacy studies; the record does not report outcomes that answer whether AZD7442 prevents or treats COVID-19.
Further limitations are that the registry record does not report detailed methods for missing data, multiplicity adjustment, interim analyses, or the statistical analysis of the safety endpoint. It also does not report details of how dose-escalation decisions were made or a trial-specific sample-size justification. These gaps constrain assessment of the precision, robustness, and intended inferential scope of the results.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: AZD7442 - a Potential Combination Therapy for the Prevention and Treatment of COVID-19 — NCT04507256.
- Registry record last updated 2024-10-18; status last verified 2024-10.
- Results first posted 2024-10-18.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
The registry record describes NCT04507256, a completed Phase I randomized, double-blind, placebo-controlled study with a sequential model. It evaluated AZD7442 safety, tolerability and pharmacokinetics in healthy adults, with an enrollment of 60. The record lists a start date of 2020-08-18 and a primary completion date of 2021-10-19.
The primary outcome was the number of participants with adverse events and serious adverse events, assessed from screening day (Day -28) until the follow-up/end of treatment visit (Day 361). Serious adverse-event counts and deaths were zero in each recorded group. Other adverse-event counts were reported separately. The registry describes the study as intended to enable future efficacy studies; it does not report efficacy results.