Registration Dossier

Administrative data

Endpoint:
sensitisation data (humans)
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
From May 23, 1984 to June 28, 1984
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Well designed study which meets basic scientific principles.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1984
Report Date:
1984

Materials and methods

Type of sensitisation studied:
skin
Study type:
study with volunteers
Principles of method if other than guideline:
The study was performed to determine the skin sensitization potential of test substance in humans under controlled patch test conditions. Human subjects were exposed to test substance during induction and challenge phases. Individuals were observed for signs of sensitization during the study period.

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Details on test material:
- Name of test material: N,N-Bis-(2-hydroxyethyl)-p-phenylenediamine sulfate
- TSIN: 3780284
- Substance type: Pure active substance
- Physical state: Dark purple gel
- Stability under test conditions: Not reported
- Storage condition of test material: In refrigerator

Method

Type of population:
general
Ethical approval:
confirmed and informed consent free of coercion received
Subjects:
- Number of subjects exposed: 116 subjects enrolled and 104 subjects completed the study
- Sex: Females
- Age: 18-65 yrs
- Race: Caucasian
- Demographic information: Not reported
Clinical history:
No details on clinical history of subjects were reported in the study report.
Route of administration:
dermal
Details on study design:
TYPE OF TEST(S) USED: Patch test (epicutaneous test)

ADMINISTRATION
- Type of application: Occlusive
- Description of patch: Closed, from Parke-Davis Readi bandage
- Vehicle : The composition of vehicle was as follows:
Isopropanol………………………………….…….12%
Tween-80…………………………………………..2.0%
Natrosol……………………………………………..2.0%
Sodium sulfite…………………………………….0.05
Dye……………………………………………………..3.0%
Water………………………………………………….100% (Q.S)

- Concentrations: 3% in vehicle
- Volume applied: 0.1 mL
- Exposure period: 24 h after application
- Scoring schedule: Induction sites were examined 48 h after application and the induction patches applied on Friday were evaluated on Monday (after 72 h). Challenge site were examined at 48 and 72 h after patch application.
- Removal of test substance: 24 h after each patch application.

PROCEDURE FOR INDUCTION EXPOSURE 
- Test sites: Infrascapular area of the back, either to the right or left of the midline. Prior to application of the patches, test sites were outlined with a gentian violet skin marker.
- Subjects were required to remove patches at approx. 24 h after application. They returned to the facility at 48 h intervals to have the sites evaluated and identical were patches applied to the same sites. Patches applied on Friday were removed by subjects after 24 h and sites were evaluated on the following Monday, i.e., 72 h after patch application.

PROCEDURE FOR CHALLENGE EXPOSURE
- After induction phase, subjects were rested for 14 d prior to challenge.
- Challenge Phase was initiated during the sixth week of the study, with identical patches applied to sites previously unexposed to the test substance. These patches were removed after 24 h.

EXAMINATIONS
- Grading/Scoring system: The symbols found in the computer data accompanying this report were used to express the response observed at the time of examination :
No reaction……………………………………………………………………………………………………………………………..………….-
Doubtful response, barely perceptible erythema, only slightly different from surrounding skin …….................................…?
Definite erythema and no edema……………………………………………………………………….…………………………….............+
Definite erythema with minimal or doubtful edema………………………………………………………………..................................+*
Definite erythema and Definite edema……………………………………………………………………………………...................……++
Definite erythema and definite edema and vesiculation…………………………………………………………….............................+++
Panelist absent…………………………………………………………………………………………………………………………………...X

Results and discussion

Results of examinations:
- Total 104/116 subjects completed the study. 12 subjects were dropped out for reasons unrelated to the product.

SYMPTOMS
- Three subjects developed reactions after induction and/or challenge.
- First subject developed definite erythema with minimal or doubtful edema (+*) at 48 h and definite erythema and no edema (+) at 72 h after challenge application. These results were probably irritation, although low level sensitization cannot be entirely ruled out.
- Second subject developed definite erythema and definite edema and vesiculation (+++) reactions at both 48 and 72 h, with some spreading of the reactions beyond the application site. The reactions were indicative of definite sensitisation.
- Third subject developed reactions during induction indicative of possible pre-sensitisation. The pre-sensitisation was confirmed by challenge testing to both the test substance and vehicle. After test substance treatment, signs of definite erythema and definite edema (++) (at 48 and 72 h) were observed on the back. Signs of doubtful response, barely perceptible erythema, only slightly different from surrounding skin (?) at 48 h and definite erythema and definite edema (++) at 72 h were observed on forearm. After treatment with vehicle, signs of definite erythema (at 48 h) and definite edema (++) (at 72 h) were observed on the back and signs of definite erythema with minimal or doubtful edema (+*) at 48 h and signs of definite erythema, definite edema (++) were observed on the forearm at 72 h. These reactions were interpreted as evidence of pre-sensitisation to the vehicle.

NO. OF PERSONS WITH/OUT REACTIONS COMPARED TO STUDY POPULATION
- Number of subjects with positive reactions: 2/104
- Number of subjects with negative reactions: 101/104
- Number of subjects with equivocal reactions: 1/104

Applicant's summary and conclusion

Conclusions:
A definite evidence of sensitization was found in one subject, and possibly in a second subject, to the test substance. In addition, one individual developed reactions to all three materials (two other substances were tested in parallel), which were interpreted as pre-sensitization, probably to the vehicle.
Executive summary:

The study was designed to evaluate the skin sensitisation potential of N,N-Bis-(2-hydroxyethyl)-p-phenylenediamine sulfate (A050) when applied to human skin in the human repeat insult patch test.

A total of 116 Caucasian female subjects (18-65 years) were involved in the study. 104/116 subjects completed the study.

Each study enrollment group participated over a 6-week period involving 3 phases: (1) Induction, (2) Rest, and (3) Challenge. Test substance (3%) was applied under occlusive condition at a dose level of 0.1 mL (applied to each patch).

During the induction phase, patches (Closed, from Parke-Davis Readi bandage) were applied to infrascapular area of the back, either to the right or left of the midline. The subjects were required to remove the patches approx. 24 h after application. Subjects returned to the facility at 48-h intervals (72 h after a weekend if applied on Friday) to have the sites evaluated and identical patches applied to the same sites. A total of 9 Induction patches were applied during the period of 3 weeks.

After induction phase, subjects rested for 14 d prior to challenge.

The challenge phase was initiated during the sixth week of the study, with identical patches applied to sites previously unexposed to the test substance. These patches were removed after 24 h. The sites were graded 48 and 72 h after challenge patch application.

All subjects were instructed to notify the staff if they experienced any discomfort beyond mild itching or observed any adverse changes at the evaluation sites while on the study or within two weeks of completing the study.

Three subjects developed reactions after induction and/or challenge.

The first subject developed definite erythema with minimal or doubtful edema (+*) at 48 h and definite erythema and no edema (+) at 72 h after challenge application. These results were probably irritation, although low level sensitization cannot be entirely ruled out.

The second subject developed definite erythema, definite edema and vesiculation (+++) reactions at both 48 and 72 h, with some spreading of the reactions beyond the application site. The reactions were indicative of definite sensitisation.

The third subject developed reactions during induction indicative of possible pre-sensitisation. The pre-sensitisation was confirmed by challenge testing to both the test substance and vehicle. These reactions were interpreted as evidence of pre-sensitisation to the vehicle.

A definite evidence of sensitization was found in one subject, and possibly in a second subject, to the test substance. In addition, one individual developed reactions to all three materials (two other substances were tested in parallel), which were interpreted as pre-sensitization, probably to the vehicle.