Cutaneous Acceptability, Comedogenic Potential and Efficacy of Two Cosmetic Products Used in Synergy

The evaluation of Effaclar gel and Effaclar Duo+ used in synergy in acneic patients has been conducted under dermatological control by Dermscan that is certified by the International Standards Organization (ISO) 9001-2015.

Each study report is subjected to a quality inspection by a member of Dermscan. A certificate of quality inspection signed by the proofreader (not involved in the study) who checked the report is enclosed in each study. The inspection of the study report allows to confirm that the results reflect exactly the study raw data and that the study fulfills any standard and regulatory requirements.

With regard to the statistical analysis, and in particular the descriptive analysis, each quantitative criterion and scores will be summarized using the following standard statistics

• number of valid values
• number of missing values,
• means,
• standard deviations,
• standard errors of the mean,
• medians,
• minimum values and
• maximum values for each time point by product. The qualitative data will be summarized in frequency (N) and percentage (%).

With regard to the statistical analysis, and in particular the inferential analysis, for each quantitative assessed criterion, a mixed ANOVA model for repeated measurements (fixed factors included: product with 2 levels and time with 3 levels) will be fitted to raw data.

To take into account the correlation between data obtained from a same subject, an unstructured variance -covariance matrix (UN@UN) will be set.

The specific contrasts of interest on adjusted means (LS-Means) will be built:

• to assess the change on (Di) from baseline (D0) for each product
• to test whether products differ significantly in terms of change from baseline (Di-D0).

The participants have the right to exit from the study at any time and for any motive in compliance with the Helsinki Declaration (1964) and its successive updates. The investigator can also interrupt the person's participation in the study prematurely in the case of a disease occurrence, a pregnancy or the occurrence of an adverse reaction.

Every premature exit must be classified under one of the following headings:

• presence of a non-inclusion criteria;
• Undesirable Effect / Adverse Event occurrence;
• Serious Adverse Event / Serious Adverse Effect occurrence;
• withdrawal of consent;
• lost to follow-up;
• appearance of non-inclusion criteria;
• non-adherence to the protocol;
• other reason. All the adverse events and serious adverse events are reported in the case report form and the study report. 70 persons have been pre-included in order to include 46 participants and to obtain results on 42 (±10%) participants minimum in each centre (2 centers in total).

The personnel in charge of the study collects data into individual case report forms in electronic or paper format and/or directly from measurement software. When information is collected in paper format, the simple/double data entry is then done from these supports by the designed operator(s), without any interpretation, in specific EXCEL databases. The Project Manager or assistant checks the double data entry by comparing both databases.

Then the coherence of the whole data set is checked as well as formulas used in the EXCEL tables (calculation formulas, selected data…).

When all the controls are done, the database is locked.