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 GEMINI Study - A Study of Saquinavir/Ritonavir in Treatment-Naive Patients With HIV-1 Infection (NCT00105079), a randomized phase 3 study. The primary outcome is Number of Patients With Human Immunodeficiency Virus Type 1 (HIV-1) Ribonucleic Acid (RNA) Viral Load <50 Copies/mL.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00105079 |
| Phase | Phase 3 |
| Condition | HIV Infections |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 337 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Hoffmann-La Roche |
| Results posted | Yes |
2. Clinical Question
Population
Adults with HIV-1 infection who had received no prior HIV treatment. The primary endpoint description identifies the intent-to-treat population; the registry record does not provide further eligibility details in the posted results.
Intervention
Saquinavir/ritonavir twice daily plus emtricitabine/tenofovir once daily. The regimen description specifies saquinavir mesylate 1000 mg twice daily, ritonavir 100 mg twice daily, and emtricitabine/tenofovir disoproxil fumarate 200/300 mg daily for 48 weeks.
Comparator
Lopinavir/ritonavir twice daily plus emtricitabine/tenofovir once daily. The regimen description specifies lopinavir/ritonavir 400/100 mg twice daily and emtricitabine/tenofovir disoproxil fumarate 200/300 mg daily for 48 weeks.
Primary question
At Week 48, how many participants in each randomized group had HIV-1 RNA viral load <50 copies/mL? The registry record identifies this outcome but does not report the group results or a statistical comparison.
This is a randomized comparison of two combination regimens in treatment-naive participants. The question is comparative: it concerns the number meeting a stated viral-load threshold in each group at the specified visit. The registry record does not report an effect estimate, uncertainty interval, or test for that primary comparison, so the relative outcome cannot be judged from the posted results.
3. Trial Design
The GEMINI study is described as a Phase 3, randomized, open-label, parallel-group, two-arm trial. The registry record lists enrollment of 337 and status as completed. It identifies Hoffmann-La Roche as the sponsor and gives a start date of 2005-04 and primary completion date of 2007-08.
Participants were assigned to saquinavir/ritonavir with emtricitabine/tenofovir or lopinavir/ritonavir with emtricitabine/tenofovir. The planned treatment period in the arm descriptions is 48 weeks. The registry summary describes an anticipated time on study treatment of 3-12 months and a target sample size of 100-500 individuals. These are registry descriptions, not evidence that every participant completed the planned treatment period.
Randomization supports a comparison between assigned groups by reducing systematic differences at allocation, on average. Open-label means masking was listed as none; the registry record does not describe blinding of participants, clinicians, or outcome assessors. Because the endpoint is based on a laboratory measurement, it is distinct from a subjective assessment, but the registry does not report assay procedures or safeguards against assessment bias.
The registry record does not report the randomization sequence method, allocation concealment, stratification factors, protocol deviations, or detailed treatment adherence. It also does not give a participant flow account in the posted results. Those omissions limit assessment of how assignment was implemented and how the enrolled population contributed to the endpoint 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.
Overall Study
| Stage | Saquinavir/Ritonavir | Lopinavir/Ritonavir |
|---|---|---|
| STARTED | 167 | 170 |
| Safety Population | 163 | 168 |
| COMPLETED | 128 | 135 |
| NOT COMPLETED | 39 | 35 |
Reasons for not completing this period:
| Reason | Saquinavir/Ritonavir | Lopinavir/Ritonavir |
|---|---|---|
| Adverse Event | 5 | 12 |
| Death | 3 | 1 |
| Lost to Follow-up | 12 | 12 |
| Lack of Efficacy | 9 | 3 |
| Refused treatment | 6 | 4 |
| Violation of selection criteria at entry | 0 | 2 |
| Protocol Violation | 1 | 0 |
| Other | 3 | 1 |
Analysis population for the primary outcome, as defined in the registry: intent-to-treat (ITT) Population
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
| Characteristic | Unit | Saquinavir/Ritonavir | Lopinavir/Ritonavir | Total |
|---|---|---|---|---|
| Participants analysed | 167 | 170 | 337 | |
| Age Continuous | years | 38.3 (SD 9.31) | 37.9 (SD 9.60) | 38.1 (SD 9.45) |
| Sex: Female, Male: Female | Participants | 31 | 39 | 70 |
| Sex: Female, Male: Male | Participants | 136 | 131 | 267 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Patients With Human Immunodeficiency Virus Type 1 (HIV-1) Ribonucleic Acid (RNA) Viral Load <50 Copies/mL, measured over Week 48.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the number of participants in the intent-to-treat population with HIV-1 RNA viral load <50 copies/mL at Week 48. Blood samples were collected at the Week 48 clinic visit for viral-load measurement. The endpoint therefore classifies participants according to whether their measured viral load fell below the stated threshold at that assessment; the registry describes a count, not a continuous change score.
A threshold outcome is clinically and statistically interpretable as a proportion of participants meeting a defined virologic criterion, while the registered outcome is expressed as a number of participants. The two treatment groups can in principle be compared on that binary classification. General statistical context: binary outcomes retain whether each participant crossed the chosen threshold, but do not convey how far a participant’s value was from it. A threshold also makes the result dependent on the specified cutoff and assessment time.
The registry lists viral-load outcomes using both <50 and <400 copies/mL among secondary outcomes, as well as change from baseline in viral load. Those are distinct measures and should not be treated as interchangeable with the primary endpoint. The primary endpoint is specifically the Week 48 count below 50 copies/mL. Although the endpoint and population are defined, the number meeting the threshold in either arm is not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies the primary outcome and its assessment time, but does not report the arm-specific counts for participants with HIV-1 RNA <50 copies/mL at Week 48. It also lists zero analyses. As a result, the posted results do not support a numerical estimate of the difference between regimens for this primary endpoint, nor an assessment of its statistical precision.
No confidence interval, p-value, adjusted estimate, or unadjusted estimate for the primary comparison is reported in the registry record. General statistical context: an effect estimate describes the size and direction of a group contrast, while a confidence interval describes the range of values reasonably compatible with the data under the analysis assumptions. A p-value addresses compatibility with a specified null model; by itself, it does not measure clinical importance or the probability that a treatment effect is true. Those interpretations require actual reported estimates and the associated analysis details, which are not reported in the registry record.
The registered endpoint is a count of participants meeting a threshold, with an intent-to-treat population specified. The enrollment total of 337 does not reveal how many participants were included in the Week 48 analysis or how missing measurements were handled. No group-specific denominators for the primary endpoint are reported in the registry record. It would therefore be inappropriate to infer event proportions, a treatment contrast, or precision from the overall enrollment figure.
The record includes secondary outcome descriptions: counts below the <50 and <400 copies/mL thresholds, change from baseline in viral load, change from baseline in CD4+ lymphocyte count, participants assessed for adverse events, and discontinuations due to abnormal laboratory parameters. Their inclusion shows that several types of outcome were registered, but the results and analyses for these measures are not reported in the registry record. No secondary endpoint should be used as a substitute for the missing primary comparison.
The registry’s serious adverse event information is descriptive and does not fill this efficacy gap. The reported affected counts and listed serious-event terms characterize safety reporting, but they are not evidence about the primary viral-load endpoint. Overall, the registered design frames a randomized comparison, while the posted results available in the registry record do not permit conclusions about the direction, magnitude, or precision of the primary outcome difference.
9. Statistical Methods Explained
The trial is registered as randomized, open-label, and parallel-group. Those design labels describe how the comparison was organized, but do not supply the details of the statistical analysis. The registry record lists zero analyses. It does not report a primary-outcome estimate, a test statistic, a confidence interval, or a p-value.
What does a randomized comparison estimate?
General statistical context: random assignment aims to make the groups comparable at baseline in expectation. An analysis comparing participants according to their assigned groups can estimate the effect of assignment to one regimen rather than the other, subject to the analysis population, missing data, outcome definition, and other assumptions. Randomization does not guarantee identical groups in a particular trial, and it does not resolve problems caused by missing outcomes or departures from the intended analysis.
The registry specifies an intent-to-treat population for the primary outcome. In general, an intent-to-treat analysis retains participants in their randomized groups, rather than regrouping them according to treatment received. The registry record does not report the exact operational definition used for this population, who was included in the endpoint analysis, or how participants with unavailable Week 48 measurements were treated.
How should a binary endpoint be analyzed?
General statistical context: a binary endpoint has two states for each participant, such as meeting or not meeting the stated viral-load threshold. An analysis can compare the groups using counts, proportions, or a model for a binary outcome. The choice affects the form of the estimate and may affect its interpretation. The registry’s primary outcome is described as a number of participants, but the particular statistical method used to compare groups is not reported in the registry record.
A difference in proportions expresses an absolute contrast; a ratio expresses a relative contrast. These are different estimands and need not communicate the same perspective. No such contrast is reported for the primary endpoint. General statistical context: estimates should be read alongside confidence intervals, which convey uncertainty under the assumptions of the analysis. A confidence interval is not a guarantee that the true effect lies in the interval, and its width depends on factors including the amount of information and the variability of the data.
What is known about the analysis plan?
The registry record describes the endpoint, population, and time point, but does not report the planned test, model, covariate adjustment, handling of protocol deviations, or any analysis hierarchy. A detailed statistical analysis plan is not reported in the registry record. The record also does not report interim analyses, stopping rules, or a sample-size justification. These details should not be inferred from the Phase 3 designation, the randomized design, or the enrollment total.
General statistical context: adjustment for baseline variables can sometimes improve precision, but an adjusted result answers a question conditional on the specified model and covariates. Unadjusted and adjusted estimates can differ. Since neither analysis details nor primary estimates are reported in the registry record, there is no basis for describing the posted primary comparison as adjusted or unadjusted.
What do the planning illustrations mean?
General statistical context: sample-size planning asks how many participants would be needed under stated assumptions to have a chosen probability of detecting an effect at a specified significance level. Such calculations depend on the assumed effect, outcome variability, allocation, analysis, and design. A planning illustration based on an observed effect is not an estimate of what the trial was designed to detect, unless the record establishes that those were its original design assumptions. The registry record does not report its sample-size justification.
The planning assumptions described with the posted illustrations use a two-sided significance level of 0.05, equal allocation, and a normal approximation, with effects set as fractions of the observed effect. They are planning illustrations, not observed power. They do not establish that the trial had a particular probability of finding a result, and they do not replace a reported treatment estimate or confidence interval. The registry’s own design assumptions and any planned power calculation are not reported in the registry record.
What can be inferred from the available statistical record?
Only the registered outcome definition, its Week 48 assessment, the named analysis population, and the stated trial design can be described. Since no primary analysis is listed and no group results or uncertainty estimates are reported, statistical significance, effect size, and precision cannot be evaluated. General statistical context: absence of a reported analysis is not evidence of no difference; it means the record does not provide an analysis from which to assess a difference.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists six outcome measures in total, including the primary endpoint and secondary outcomes covering viral-load thresholds, change in viral load, change in CD4+ lymphocyte count, adverse-event assessment, and treatment discontinuation due to abnormal laboratory parameters. Several outcomes create multiple opportunities to test hypotheses. General statistical context: when many outcomes or comparisons are examined, the chance of at least one apparently unusual result can increase unless the analysis plan accounts for multiplicity. The registry record does not report a multiplicity adjustment, a testing hierarchy, or which secondary outcomes were considered confirmatory.
The record specifies an intent-to-treat population for the primary endpoint, but does not report the number analyzed in that population or the handling of missing Week 48 viral-load measurements. It does not describe imputation, assumptions about missingness, censoring rules, or sensitivity analyses. These details matter because participants without an observed endpoint may affect both the estimated group results and the uncertainty around them.
The registry record also does not report analysis populations for the secondary outcomes, or whether participants were analyzed according to assigned treatment for those measures. The posted record therefore does not establish how missing data or multiplicity were handled in the actual analyses. These are limitations of the available reporting, not evidence that particular methods were or were not used outside the registry record.
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 |
|---|---|---|---|
| Saquinavir/Ritonavir | 24 | 163 | 14.7% |
| Lopinavir/Ritonavir | 19 | 168 | 11.3% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Saquinavir/Ritonavir | 76 of 163 |
| Lopinavir/Ritonavir | 92 of 168 |
Most frequent serious adverse event terms
| Event term | Organ system | Saquinavir/Ritonavir | Lopinavir/Ritonavir |
|---|---|---|---|
| Pregnancy | Pregnancy, puerperium and perinatal conditions | 1 of 163 | 2 of 168 |
| Cerebral toxoplasmosis | Infections and infestations | 0 of 163 | 2 of 168 |
| Kaposi's sarcoma | Neoplasms benign, malignant and unspecified (incl cysts and polyps) | 1 of 163 | 1 of 168 |
| Bronchitis viral | Infections and infestations | 0 of 163 | 1 of 168 |
| Clostridial infection | Infections and infestations | 0 of 163 | 1 of 168 |
| Cytomegalovirus oesophagitis | Infections and infestations | 1 of 163 | 0 of 168 |
| Encephalitis cytomegalovirus | Infections and infestations | 1 of 163 | 0 of 168 |
| Gastroenteritis | Infections and infestations | 1 of 163 | 0 of 168 |
| Herpes zoster | Infections and infestations | 0 of 163 | 1 of 168 |
| Meningitis | Infections and infestations | 0 of 163 | 1 of 168 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Saquinavir/Ritonavir | Lopinavir/Ritonavir |
|---|---|---|---|
| Diarrhoea | Gastrointestinal disorders | 46 of 163 | 77 of 168 |
| Nausea | Gastrointestinal disorders | 40 of 163 | 55 of 168 |
| Vomiting | Gastrointestinal disorders | 21 of 163 | 28 of 168 |
| Upper respiratory tract infection | Infections and infestations | 11 of 163 | 23 of 168 |
| Fatigue | General disorders | 15 of 163 | 12 of 168 |
| DIZZINESS | Nervous system disorders | 12 of 163 | 14 of 168 |
| Headache | Nervous system disorders | 8 of 163 | 14 of 168 |
| DECREASED APPETITE | Metabolism and nutrition disorders | 9 of 163 | 8 of 168 |
| INSOMNIA | Psychiatric disorders | 6 of 163 | 10 of 168 |
| Bronchitis | Infections and infestations | 10 of 163 | 5 of 168 |
Serious events with the highest arm-level rate: cerebral toxoplasmosis (1.2%), pregnancy (1.2%), cytomegalovirus oesophagitis (0.6%), encephalitis cytomegalovirus (0.6%), gastroenteritis (0.6%).
For the saquinavir/ritonavir group, the registry reports 24 participants affected by serious adverse events among 163 at risk, and 76 affected by other adverse events among 163 at risk. For the lopinavir/ritonavir group, it reports 19 participants affected by serious adverse events among 168 at risk, and 92 affected by other adverse events among 168 at risk. These are the recorded counts and denominators; no additional comparison or rate has been calculated.
The registry lists cerebral toxoplasmosis and pregnancy at 1.2% each, and cytomegalovirus oesophagitis, encephalitis cytomegalovirus, gastroenteritis, and orchitis at 0.6% each, among the top serious-event terms. These term percentages are descriptive. The registry record does not specify in this listing whether participants could contribute to more than one term, so the terms should not be summed or treated as mutually exclusive categories.
Death counts are not reported in the registry record. The listed event data alone do not establish causation, comparative risk, or statistical significance. Differences in the reported counts should be interpreted with the available denominators and the absence of a reported safety analysis in mind.
12. What the Result Does, and Does Not, Mean
The registry record establishes that GEMINI was designed as a randomized comparison of two antiretroviral combinations in treatment-naive adults with HIV-1 infection. It defines a primary endpoint: the number of participants in the intent-to-treat population with HIV-1 RNA <50 copies/mL at Week 48. This makes the intended efficacy question clear.
However, the registry record does not report the primary outcome counts by group or an analysis comparing them. It therefore does not show which group had more participants meeting the threshold, the size of any difference, or how precisely such a difference was estimated. No conclusion about efficacy for the primary endpoint follows from the design description alone.
General statistical context: a randomized design can support a causal comparison when assignment, follow-up, outcome ascertainment, and analysis are appropriately implemented. Its interpretation still depends on adherence to the analysis plan, handling of missing data, and the quality of outcome reporting. The registry record does not provide enough analysis detail to assess those features fully.
The endpoint is a threshold measured at a single specified visit, not a complete account of viral-load trajectories, treatment experience, or all outcomes that may matter to participants. Secondary outcomes are named, but their results are not reported in the registry record. The adverse-event counts and serious-event terms offer descriptive safety information, not a replacement for efficacy results or a complete benefit-risk comparison.
Accordingly, the defensible interpretation is limited to the trial’s question, design, and recorded descriptive safety information. The available registry record does not establish that either regimen produced a better Week 48 primary outcome, nor does it establish that the regimens were equivalent. Both claims would require comparative results and an analysis with its uncertainty reported.
13. Why This Trial Matters Statistically
This trial illustrates why a clearly specified randomized question and a reported analysis are both necessary for statistical interpretation. The registry describes two treatment groups, an intent-to-treat primary population, a threshold-based viral-load outcome, and a Week 48 assessment. Those elements identify what the planned comparison was meant to address.
At the same time, a defined endpoint is not itself an outcome result. Without group counts, denominators for the primary endpoint, an effect estimate, and its uncertainty, readers cannot assess the magnitude or precision of the comparison. The registry record lists zero analyses, which sharply limits what can be learned about the primary statistical question from the posted results.
The study also demonstrates why outcome families need transparent planning and reporting. Viral-load thresholds, changes from baseline, immune-cell counts, safety measures, and treatment discontinuations answer different questions. General statistical context: when many endpoints are assessed, it is important to distinguish the prespecified primary question from exploratory or secondary questions and to report how multiplicity was addressed. That information is not reported in the registry record.
Finally, the registered serious-event counts show the importance of separating descriptive safety reporting from formal comparative inference. Counts and event terms can help characterize what was recorded, but do not alone establish comparative risks or causation. Statistical interpretation depends not only on the design, but also on complete outcome reporting, transparent analysis methods, and uncertainty estimates.
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 main limitation for interpreting the trial statistically is that the registry record does not report the primary endpoint results or an analysis comparing the randomized groups. There are no group-specific Week 48 counts, primary-outcome denominators, effect estimates, confidence intervals, or p-values in the posted results. The listed enrollment of 337 cannot substitute for those missing details.
The registry identifies an intent-to-treat population for the primary endpoint but does not report the number analyzed, the handling of missing viral-load measurements, or sensitivity analyses. It does not provide participant flow or explain discontinuations in a way that can be connected to primary endpoint availability. The consequences of missing data for the reported outcome therefore cannot be evaluated.
The study is described as open-label, with masking listed as none. The registry does not report outcome-assessment safeguards or detailed laboratory methods. It also does not report the statistical analysis plan, sample-size justification, randomization implementation, multiplicity strategy, or interim analyses. These are reporting gaps in the registry record; they do not establish that such procedures were absent from the trial.
The safety information is descriptive, and death counts are not reported in the registry record. The listed serious-event terms do not provide a full account of adverse events or establish causal attribution. Finally, the absence of posted secondary analyses means the named outcomes cannot be used to fill the primary-outcome gap.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: GEMINI Study - A Study of Saquinavir/Ritonavir in Treatment-Naive Patients With HIV-1 Infection — NCT00105079.
- Registry record last updated 2011-11-02; status last verified 2011-09.
- Results first posted 2011-11-02.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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18. Record Summary
The registry record describes a completed, Phase 3, randomized, open-label, parallel-group study with enrollment of 337. It compared saquinavir/ritonavir plus emtricitabine/tenofovir with lopinavir/ritonavir plus emtricitabine/tenofovir in treatment-naive adults with HIV-1 infection.
The primary endpoint was the number of participants in the intent-to-treat population with HIV-1 RNA <50 copies/mL at Week 48. The registry record lists zero analyses and does not report the group results or a statistical comparison for this endpoint. It names secondary outcomes and provides descriptive adverse-event counts and serious-event terms, but does not report a primary efficacy estimate, its precision, or details of missing-data handling.