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 Study to Evaluate the Contraceptive Efficacy/Safety of a Low Dose EE/LNG Transdermal Contraceptive Delivery System (NCT01181479), a randomized phase 3 study. The primary outcome is Pregnancy.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01181479 |
| Phase | Phase 3 |
| Condition | Contraception |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 1504 |
| Arms in the primary outcome | 3 |
| Lead sponsor | Agile Therapeutics |
| Results posted | Yes |
2. Clinical Question
Population
The pregnancy analysis included subjects in the safety population, age 17-35 with a BMI <32. The record reports 1504 participants enrolled in the study overall, but does not state that every enrolled participant contributed to every outcome group.
Intervention
The intervention of interest was AG200-15, a transdermal delivery system containing ethinyl estradiol and levonorgestrel. One group is listed as receiving AG200-15 for cycles 1-13; another outcome group is listed as receiving it for cycles 7-13.
Comparator
The oral contraceptive was Lessina, also containing ethinyl estradiol and levonorgestrel. The arm description says Lessina was used for 6 cycles followed by AG200-15 for 6 cycles. The registry record does not explain how that sequence was handled in the arm-level pregnancy estimates.
Primary question
The study assessed contraceptive efficacy using the Pearl Index, an estimate of pregnancies per 100 woman-years of product use. The posted results give separate estimates for the listed treatment groups, but do not report a two-arm comparison or an estimated treatment difference.
The registry describes an open-label, randomized study intended to evaluate the efficacy and safety of a low-dose transdermal contraceptive delivery system in comparison with a low-dose oral contraceptive. The central statistical question is how to interpret the reported pregnancy rates and how much uncertainty surrounds each estimate.
The reported Pearl Index is 5.41 for AG200-15 for cycles 7-13, with a 95% confidence interval of 2.35 to 8.46. For Lessina, the estimate is 6.67, with a 95% confidence interval of 0.84 to 12.5. For AG200-15 for cycles 1-13, the estimate is 6.43, with a 95% confidence interval of 4.13 to 8.72. These are separate arm-level estimates, not a reported direct contrast.
The clinical question can therefore be described, but the posted statistics do not establish whether the transdermal and oral regimens differ. The arm descriptions and distinct outcome timeframes also matter: Lessina is described as part of a sequence that later includes AG200-15, while the outcome record separately identifies an AG200-15 group covering cycles 1-13 and another covering cycles 7-13. The registry record does not explain the construction of those outcome groups in further detail.
3. Trial Design
The study is identified as phase 3, randomized, open-label, and parallel-group. It enrolled 1504 participants and is marked completed. The recorded start is 2010-08, and primary completion is recorded as 2011-12. Agile Therapeutics is listed as the sponsor. The condition is contraception.
The study title and official title describe an evaluation of a transdermal contraceptive delivery system against a low-dose oral contraceptive containing 0.02 mg EE and 0.1 mg LNG in a 21-day regimen. The named transdermal product is AG200-15, containing ethinyl estradiol and levonorgestrel. The comparator is Lessina, also described as containing ethinyl estradiol and levonorgestrel.
The record names an AG200-15 arm covering cycles 1-13 and a Lessina crossover-to-AG200-15 arm. The latter is described as Lessina for 6 cycles followed by AG200-15 for 6 cycles. The registry also lists an outcome group called AG200-15 for Cycle 7-13. This means the posted outcome categories do not simply appear as one uninterrupted AG200-15 group versus one uninterrupted Lessina group. The record does not explain how the crossover sequence, cycle windows, and analysis groups relate to one another.
The pregnancy outcome lists 675 participants for AG200-15 for Cycle 7-13, 220 for Lessina, and 827 for AG200-15 for Cycle 1-13. These are the group counts attached to the reported outcome; the record does not clarify how they relate to the overall enrollment, or whether every participant contributed data for the full stated period.
Masking is recorded as none. No further detail about concealment procedures, allocation implementation, treatment adherence, or protocol deviations is reported in the registry record. The design label indicates a randomized parallel-group study, while the Lessina arm description explicitly includes a later switch to AG200-15. These details should be kept in view when interpreting the arm-specific estimates rather than treating all listed groups as a simple, single-time-point head-to-head contrast.
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.
Subjects Receive AG200-15 or Lessina
| Stage | AG200-15 (Cycles 1-13) | Lessina (Cycles 1-6) | Lessina (Cycles 1-6) Crossover to AG200-15 (Cycles 7-13) |
|---|---|---|---|
| STARTED | 1129 | 375 | 0 |
| COMPLETED | 485 | 249 | 0 |
| NOT COMPLETED | 644 | 126 | 0 |
Crossover Subjects Recieve AG200-15
| Stage | AG200-15 (Cycles 1-13) | Lessina (Cycles 1-6) | Lessina (Cycles 1-6) Crossover to AG200-15 (Cycles 7-13) |
|---|---|---|---|
| STARTED | 0 | 0 | 249 |
| COMPLETED | 0 | 0 | 150 |
| NOT COMPLETED | 0 | 0 | 99 |
Analysis population for the primary outcome, as defined in the registry: Subjects in the Safety population, age 17-35 with a BMI \<32, were analyzed.
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: Safety Population
| Characteristic | Unit | AG200-15 | Lessina Crossover to AG200-15 | Total |
|---|---|---|---|---|
| Participants analysed | 1043 | 230 | 1273 | |
| Age, Categorical: <=18 years | Participants | 5 | 2 | 7 |
| Age, Categorical: Between 18 and 65 years | Participants | 1038 | 228 | 1266 |
| Age, Categorical: >=65 years | Participants | 0 | 0 | 0 |
| Age, Continuous | years | 26.38 (SD 5.663) | 26.86 (SD 5.738) | 26.46 (SD 5.677) |
| Sex: Female, Male: Female | Participants | 1043 | 230 | 1273 |
| Sex: Female, Male: Male | Participants | 0 | 0 | 0 |
| Region of Enrollment: United States | participants | 1043 | 230 | 1273 |
6. Primary Endpoint
The registry lists the primary outcome as Pregnancy, measured over AG200-15: 6 months; Lessina: 6 months; AG200-15: 1 year.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | 95% Confidence Interval |
| Unit | Pearl Index |
| Endpoint classification | not reduced to a single comparison |
The recorded primary outcome is pregnancy measured by the Pearl Index. The registry defines this index as the number of on-therapy pregnancies times 1300 divided by the number of 28-day on-therapy cycles. It describes the result as an estimate of the number of pregnancies per 100 woman-years of product use.
The Pearl Index puts pregnancy counts in relation to time exposed to the product. This can be useful when participants contribute differing amounts of on-therapy time, since a raw count alone does not reflect how long participants were observed while using a treatment. The unit is a rate-like estimate, rather than the proportion of all participants who became pregnant over a fixed follow-up period.
The record reports a 95% confidence interval for each listed estimate. Such an interval conveys statistical uncertainty around the estimate under the analysis used; it is not a range that contains a known fixed proportion of individual participant outcomes. Its width is relevant when judging precision. The intervals reported for the three groups are 2.35 to 8.46, 0.84 to 12.5, and 4.13 to 8.72, respectively.
The stated analysis population is the safety population, age 17-35 with a BMI <32. The listed timeframes distinguish AG200-15 at 6 months, Lessina at 6 months, and AG200-15 at 1 year. The registry record does not describe additional endpoint definitions or explain how pregnancies and exposure time were handled for the different treatment sequences.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted Pearl Index estimates are 5.41 for AG200-15 for cycles 7-13, 6.67 for Lessina, and 6.43 for AG200-15 for cycles 1-13. Each estimate is accompanied by a 95% confidence interval: 2.35 to 8.46, 0.84 to 12.5, and 4.13 to 8.72, respectively. These numbers describe the arm-level results as recorded; they do not by themselves provide an estimate of the difference between treatments.
A confidence interval gives a measure of precision for an estimate. In general, a wider interval indicates less precision than a narrower interval, while both the point estimate and interval are needed to understand the range of values compatible with the analysis. The Lessina interval, 0.84 to 12.5, is wider than the other two intervals as posted. The intervals for the AG200-15 groups also show uncertainty around their respective point estimates. None of these intervals should be read as a guarantee about the outcome for an individual participant.
The registry classifies the endpoint as a count/other outcome and indicates that values were not available or not estimable for a two-arm comparison. Accordingly, no direct treatment contrast, confidence interval for a difference, or comparison p-value is reported. The point estimates alone are not a substitute for such a contrast. In particular, comparing the numerical values informally cannot establish whether the products differ, nor can the arm-specific confidence intervals answer that question on their own.
There are also distinctions in the recorded groups and exposure periods. The AG200-15 outcome categories cover cycles 7-13 and cycles 1-13, while the Lessina outcome timeframe is 6 months and its arm description includes a switch to AG200-15 after 6 cycles. The outcome timeframe lists AG200-15 at 6 months, Lessina at 6 months, and AG200-15 at 1 year. The registry record does not explain precisely how these timeframes map to each arm estimate. This limits interpretation of the figures as direct comparisons over identical periods.
The overall enrollment was 1504, whereas the pregnancy outcome lists different participant counts for the three groups. Those counts should be understood as the group counts attached to the outcome, not assumed to describe every randomized participant or every analysis population. The record specifies the safety population and age and BMI criteria, but gives no further explanation of participant flow into each pregnancy estimate.
Thus, the posted results quantify pregnancy rates for the listed groups with stated uncertainty. They do not establish a comparative treatment effect, and the registry does not report the details needed to assess the treatment contrast, missing pregnancy data, or the construction of the analysis groups. Interpretation should remain at the level of the reported estimates and their uncertainty.
9. Statistical Methods Explained
The main statistical measure is the Pearl Index, defined in the registry as the number of on-therapy pregnancies times 1300 divided by the number of 28-day on-therapy cycles. The stated interpretation is an estimate of pregnancies per 100 woman-years of product use. In general, expressing pregnancy occurrence relative to exposure time helps account for differing lengths of time on treatment. It is a rate-style summary and should not be confused with the percentage of participants who experienced pregnancy.
The record gives one point estimate and one 95% confidence interval for each outcome group. A point estimate is a single summary calculated from the observed data; a confidence interval communicates uncertainty in that estimate. In general, a confidence interval is constructed using an analysis procedure with stated assumptions. The registry record does not identify the method used to calculate these intervals, so the interval method, its assumptions, and any adjustments cannot be assessed from the posted information.
The 95% confidence intervals are 2.35 to 8.46 for AG200-15 for cycles 7-13, 0.84 to 12.5 for Lessina, and 4.13 to 8.72 for AG200-15 for cycles 1-13. The role of an interval is to convey precision, not to turn a descriptive estimate into proof of a treatment effect. A direct treatment comparison would ordinarily require an explicitly estimated contrast with its own uncertainty measure, using a defined population, treatment exposure, and analysis approach. Such a comparison is not reported in the registry record.
How does the outcome relate to exposure time?
The Pearl Index uses on-therapy cycles as its exposure denominator. In general, the value of a rate can be affected by both the number of events and the amount of time at risk. Accurate interpretation therefore depends on how on-therapy time was defined, how treatment interruptions were handled, and how pregnancies were assigned to exposure periods. The registry gives the index formula and the listed timeframes, but details of these operational decisions are not reported in the registry record.
Time on treatment is especially relevant to the recorded regimen sequence. Lessina is described as being used for 6 cycles followed by AG200-15 for 6 cycles. The outcome timeframe separately lists Lessina at 6 months and AG200-15 at 1 year, alongside AG200-15 at 6 months. Without further details, the relation between the sequence and each reported outcome estimate cannot be determined. The record also lists distinct AG200-15 groups covering cycles 1-13 and cycles 7-13, without explaining the exact analysis windows.
Why are separate arm estimates not a treatment contrast?
Each listed Pearl Index describes one group. A comparison requires more than placing the point estimates side by side: it needs a defined estimand, specifying what difference is being assessed, in which participants, over what period, and according to which treatment assignment or exposure. The registry record does not provide a two-arm comparison for this count/other endpoint and says the values are missing or not estimable for such a comparison.
In general, a confidence interval around each arm estimate does not equal a confidence interval for the difference between arms. Statistical inference for a contrast also depends on the joint analysis and the relationship between the groups. Since no contrast is posted, no conclusion about the direction, size, or statistical significance of a treatment difference can be drawn from the arm-level intervals alone.
What can planning calculations tell readers?
Planning illustrations based on an observed effect are not observed trial outcomes and are not evidence that a study had a particular probability of detecting a treatment effect. The stated illustration assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the effect to detect is defined as a fraction of the observed effect. The record does not report the trial's own sample-size justification, so the planning illustrations should not be treated as the design rationale or as observed power.
In general, a sample-size planning calculation depends on the target effect, variability assumptions, type I error, desired power, allocation, and analysis method. Altering assumptions can change the planning result. Here, the posted endpoint is a rate-like measure, but the planning description does not give enough detail to reconstruct the trial's own design calculation. No additional sample-size values are stated in the registry record.
What remains unknown about the analysis?
The record reports one analysis and six outcome measures, but does not describe the statistical analysis plan, the interval calculation method, adjustments for covariates, interim analyses, or rules for handling multiple outcomes. It also does not report whether the estimates were adjusted or whether treatment assignment, treatment received, or a specific exposure set governed the analysis. These are not details that can be inferred from the Pearl Index values.
Over-dispersion is a general concern for count data when variability exceeds what a simple count model assumes. In general, failing to account for excess variability can affect standard errors and confidence intervals. The registry does not report a count model or indicate whether over-dispersion was assessed; consequently, no claim can be made about its role in these estimates. Likewise, no model details are given for the rate denominator or for within-participant exposure patterns.
The most defensible reading is therefore descriptive: three arm-specific Pearl Index estimates and their posted confidence intervals are available, while the method and assumptions behind the intervals and the comparative analysis are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists six outcome measures and one analysis, but it does not describe a statistical analysis plan or explain how the family of outcomes was handled. In general, evaluating multiple outcomes or multiple comparisons can increase the chance of at least one apparently notable result when no adjustment is made. Whether an adjustment was planned or used is not reported in the registry record, so the posted estimates cannot be characterized as adjusted or unadjusted for multiplicity.
The record does not report interim analyses, stopping rules, a prespecified hierarchy of outcomes, or a strategy for selecting among analyses. Their presence or absence should not be inferred from the single analysis count. The method used to construct the reported confidence intervals is also not reported.
The pregnancy analysis is described as involving the safety population, age 17-35 with a BMI <32. This identifies an analysis population criterion, but the record does not provide participant-flow details, exclusions, or counts of missing pregnancy outcomes and exposure time. The handling of participants with incomplete follow-up, treatment discontinuation, or missing endpoint information is not reported in the registry record.
It is also not clear whether the estimates follow randomized assignment, actual treatment received, or defined periods of on-therapy use. The outcome definition refers to on-therapy pregnancies and on-therapy cycles, but the analysis rules for treatment switches and interruptions are not given. These gaps make it difficult to assess missing-data assumptions or the extent to which the results preserve the randomized comparison.
The registry record therefore supports reporting the stated safety-population criteria and the posted arm-level estimates, but not a detailed account of multiplicity control, missing-data methods, or analysis-population construction.
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 |
|---|---|---|---|
| All AG200-15 | 14 | 1273 | 1.1% |
| Lessina | 4 | 344 | 1.2% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| All AG200-15 | 0 of 1273 |
| Lessina | 1 of 344 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 2.5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| All AG200-15 | 484 of 1273 |
| Lessina | 112 of 344 |
Most frequent serious adverse event terms
| Event term | Organ system | All AG200-15 | Lessina |
|---|---|---|---|
| Ovarian cyst | Reproductive system and breast disorders | 2 of 1273 | 1 of 344 |
| Appendicitis | Injury, poisoning and procedural complications | 2 of 1273 | 0 of 344 |
| Suicidal Ideation | Psychiatric disorders | 1 of 1273 | 0 of 344 |
| Pneumonia | Infections and infestations | 1 of 1273 | 0 of 344 |
| Head injury | Injury, poisoning and procedural complications | 0 of 1273 | 1 of 344 |
| Diabetic ketoacidosis | Metabolism and nutrition disorders | 0 of 1273 | 1 of 344 |
| Embolism Venous | Vascular disorders | 1 of 1273 | 0 of 344 |
| Asthma | Respiratory, thoracic and mediastinal disorders | 1 of 1273 | 0 of 344 |
| Vomiting | Gastrointestinal disorders | 1 of 1273 | 0 of 344 |
| Ankle fracture | Injury, poisoning and procedural complications | 1 of 1273 | 0 of 344 |
Most frequent non-serious adverse event terms
| Event term | Organ system | All AG200-15 | Lessina |
|---|---|---|---|
| Cervical Dysplasia | Reproductive system and breast disorders | 80 of 1273 | 17 of 344 |
| Nasopharyngitis | Infections and infestations | 74 of 1273 | 12 of 344 |
| Nausea | Gastrointestinal disorders | 58 of 1273 | 14 of 344 |
| Headache | Nervous system disorders | 50 of 1273 | 16 of 344 |
| Upper respiratory tract infection | Infections and infestations | 51 of 1273 | 7 of 344 |
| Urinary tract infection | Infections and infestations | 44 of 1273 | 11 of 344 |
| Sinusitis | Infections and infestations | 45 of 1273 | 9 of 344 |
| Human papilloma virus test positive | Investigations | 40 of 1273 | 7 of 344 |
| Vomiting | Gastrointestinal disorders | 22 of 1273 | 10 of 344 |
| Dysmenorrhea | Reproductive system and breast disorders | 20 of 1273 | 9 of 344 |
Serious events with the highest arm-level rate: head injury (0.3%), diabetic ketoacidosis (0.3%), ovarian cyst (0.3%), liver disorder (0.3%), appendicitis (0.2%).
The safety results list serious adverse events among 1273 participants in the All AG200-15 group, with 14 affected, and among 344 participants in the Lessina group, with 4 affected. Deaths are listed as 0 for All AG200-15 and 1 for Lessina. These are descriptive counts within the recorded groups. The registry does not provide a comparative safety analysis, an adjusted estimate, or a confidence interval for the difference between groups.
The record also lists other adverse events affecting 484 participants in All AG200-15 and 112 in Lessina. Seriousness and the broader category of other adverse events are distinct summaries and should not be conflated. The serious-event terms listed include Head injury, Diabetic ketoacidosis, Ovarian cyst, and Liver disorder at 0.3% each, Appendicitis at 0.2%, and Suicidal Ideation at 0.1%.
In general, adverse-event counts do not by themselves establish that a treatment caused an event. Interpretation depends on definitions, observation time, ascertainment, and participant characteristics, none of which are described in detail for these summaries. The group sizes and exposure periods also differ as recorded, so raw counts alone are not a basis for comparing rates. The listed serious-event terms and percentages describe what the registry reports; they do not establish comparative risk or causation.
12. What the Result Does, and Does Not, Mean
The result means that the registry reports three Pearl Index estimates for the listed treatment groups, each with a 95% confidence interval. The estimates are 5.41 for AG200-15 for cycles 7-13, 6.67 for Lessina, and 6.43 for AG200-15 for cycles 1-13. They are pregnancy-rate summaries expressed per 100 woman-years of product use according to the registry's definition.
The confidence intervals show that the estimates have uncertainty. They do not predict the experience of a particular participant, and they are not guarantees that a future study's result will fall within the stated limits. The precision of each estimate depends on the information and analysis behind it; the method for calculating the intervals is not reported in the registry record.
The results do not provide a direct statistical comparison between AG200-15 and Lessina. No treatment difference, comparison interval, or comparison p-value is reported. Numerical differences among the point estimates cannot by themselves establish that one regimen has a higher or lower underlying rate. Nor do separate arm-level confidence intervals serve as a formal test of a treatment contrast.
The treatment groups and periods require care in interpretation. The Lessina arm is described as switching to AG200-15 after 6 cycles. The outcome lists Lessina at 6 months and AG200-15 at 1 year, and separately includes AG200-15 for cycles 7-13 and cycles 1-13. The relationship between the sequence and the outcome categories is not explained further. The record also does not report how missing observations, treatment changes, or incomplete exposure were handled.
In general, a randomized design can support causal comparisons when a suitable analysis follows the randomization and addresses the relevant outcome and follow-up. But the posted results for this endpoint do not include that comparative analysis. The registry information therefore supports a description of the reported group-specific rates and their uncertainty, not a conclusion that the treatments are equivalent, different, effective, or ineffective.
The record does not report the trial's own sample-size justification or detailed analysis plan. Planning illustrations based on an observed effect are hypothetical design calculations, not evidence of observed power. The available results should be interpreted within those limits and alongside the stated eligibility and treatment-period definitions.
13. Why This Trial Matters Statistically
This study is statistically informative because it illustrates the distinction between reporting outcome estimates by group and estimating a treatment effect. A randomized design is recorded, but the pregnancy results presented are arm-specific Pearl Index values rather than a direct contrast. The distinction matters: descriptive estimates can characterize observed rates, while comparative inference requires a defined between-group analysis with its own uncertainty.
The Pearl Index also demonstrates why exposure time is important for some clinical outcomes. A pregnancy count is interpreted in relation to on-therapy cycles, rather than as a simple count detached from follow-up. In general, rate summaries can be useful when exposure duration varies, but their interpretation depends on consistent and clearly described definitions of time at risk and event attribution. The registry gives the formula but does not detail all the handling rules.
The recorded treatment sequence makes this issue especially visible. The Lessina arm includes later AG200-15 use, while the posted outcome groups include distinct AG200-15 cycle windows. Without a clear account of how participants and exposure periods map to each estimate, readers should avoid treating the group labels as self-explanatory or assuming a single, clean head-to-head comparison.
The confidence intervals further emphasize that point estimates are not exact quantities. Reporting intervals helps communicate precision, but the registry does not identify how they were calculated or provide a comparative interval. This is a reminder that the presence of uncertainty intervals does not automatically answer the comparative question.
Finally, the record shows why analysis-plan details matter. Multiplicity handling, missing-data methods, treatment-switch rules, and participant flow affect how clinical trial results can be interpreted. When such details are not reported, the appropriate statistical reading is narrower: describe the posted estimates, acknowledge their uncertainty, and avoid conclusions beyond the analyses recorded.
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.
Several trial-specific features limit interpretation of the pregnancy results. First, the outcome is described as a Pearl Index, but the record does not state the method used to calculate its confidence intervals. It also does not give further detail on how on-therapy exposure time, treatment interruptions, or pregnancy attribution were handled. These details are relevant to a rate based on exposure cycles.
Second, the outcome groups have different labels and periods. The registry lists AG200-15 for cycles 7-13 and AG200-15 for cycles 1-13, while the Lessina arm description includes a switch to AG200-15 after 6 cycles. The outcome timeframe lists AG200-15 at 6 months, Lessina at 6 months, and AG200-15 at 1 year. The record does not reconcile these descriptions or explain the derivation of each estimate.
Third, the participant counts associated with the pregnancy estimates differ, and the record does not provide a participant-flow account linking them to the overall enrollment of 1504. The specified analysis population is the safety population, age 17-35 with a BMI <32, but numbers excluded or missing from the endpoint analysis are not reported in the registry record.
Fourth, the registry indicates that a two-arm comparison was not available or estimable for this count/other endpoint. It therefore provides no comparative effect estimate, uncertainty interval for a treatment difference, or comparison p-value. The point estimates should not be treated as proof of a difference or equivalence.
Finally, details on the statistical analysis plan, multiplicity, missing-data handling, interim analyses, and the trial's own sample-size justification are not reported in the registry record. These omissions limit assessment of the inferential framework and the robustness of the results.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Study to Evaluate the Contraceptive Efficacy/Safety of a Low Dose EE/LNG Transdermal Contraceptive Delivery System — NCT01181479.
- Registry record last updated 2018-07-03; status last verified 2018-07.
- Results first posted 2018-07-03.
- 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 a completed, randomized, open-label, parallel-group phase 3 study sponsored by Agile Therapeutics, with 1504 participants enrolled. It evaluates the AG200-15 transdermal contraceptive delivery system and the oral contraceptive Lessina. The Lessina arm description includes 6 cycles of Lessina followed by 6 cycles of AG200-15.
Pregnancy is measured by the Pearl Index, defined as on-therapy pregnancies times 1300 divided by 28-day on-therapy cycles, with interpretation as estimated pregnancies per 100 woman-years of product use. The analysis population is described as the safety population, age 17-35 with a BMI <32.
The posted estimates are 5.41 for AG200-15 for cycles 7-13, 6.67 for Lessina, and 6.43 for AG200-15 for cycles 1-13, with 95% confidence intervals reported for each. A direct two-arm comparison is not reported. Analysis methods, missing-data handling, multiplicity procedures, and the trial's own sample-size justification are not reported in the registry record.