Registration Dossier

Diss Factsheets

Administrative data

Endpoint:
skin corrosion: in vitro / ex vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
3rd Dec 2018 - 7th Dec 2018
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2018
Report date:
2018

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to guideline
Guideline:
OECD Guideline 431 (In Vitro Skin Corrosion: Reconstructed Human Epidermis (RHE) Test Method)
Qualifier:
according to guideline
Guideline:
other: EC Guideline No. 440/2008. Part B: Methods for the Determination of Toxicity and other health effects, Guideline B.40 BIS: "In Vitro Skin Corrosion: Human Skin Model Test". Official Journal of the European Union No. L142, 31 May 2008.
GLP compliance:
yes

Test material

Constituent 1
Chemical structure
Reference substance name:
cis-N-hydroxy-3-[methyl(1H-pyrrolo[2,3-d]pyrimidin- 4-yl)amino]cyclobutanecarboxamide
EC Number:
951-622-2
Molecular formula:
C12H15N5O2
IUPAC Name:
cis-N-hydroxy-3-[methyl(1H-pyrrolo[2,3-d]pyrimidin- 4-yl)amino]cyclobutanecarboxamide

In vitro test system

Test system:
human skin model
Source species:
human
Cell type:
non-transformed keratinocytes
Vehicle:
unchanged (no vehicle)
Control samples:
yes, concurrent negative control
yes, concurrent positive control
Duration of treatment / exposure:
3 minutes - 1 hour
Number of replicates:
The test was performed on a total of 4 tissues per test item together with a negative control and positive
control. Two tissues were used for a 3-minute exposure to PF-07085579 and two for a 1-hour
exposure.

Results and discussion

In vitro

Resultsopen allclose all
Irritation / corrosion parameter:
% tissue viability
Run / experiment:
3-minute application viability (percentage of control)
Value:
ca. 102
Negative controls validity:
valid
Positive controls validity:
valid
Irritation / corrosion parameter:
% tissue viability
Run / experiment:
1-hour application viability (percentage of control)
Value:
ca. 87
Negative controls validity:
valid
Positive controls validity:
valid
Other effects / acceptance of results:
The relative mean tissue viability
obtained after the 3-minute and 1-hour treatments with PF-07085579 compared to the
negative control tissues was 102% and 87% respectively. Because the mean relative tissue
viability for PF-07085579 was not below 50% after 3 minutes treatment and not below 15%
after 1 hour treatment PF-07085579 is considered to be not corrosive.

Applicant's summary and conclusion

Interpretation of results:
study cannot be used for classification
Conclusions:
In conclusion, PF-07085579 is not corrosive in the in vitro skin corrosion test under the experimental conditions described in this report.
Executive summary:

Corrosion on a human three dimensional epidermal model (EpiDerm (EPI-200)). The

possible corrosive potential of  PF-07085579 was tested through topical application for

3 minutes and 1 hour.

The study procedures described in this report were based on the most recent OECD and EC

guidelines.

Skin tissue was moistened with 25 µL of Milli-Q water and at least 25 mg of  PF-07085579 was applied directly on top of the skin

tissue. The positive control had a mean relative tissue viability of 4.1% after the 1-hour exposure.

The absolute mean OD570 (optical density at 570  nm)  of the negative control tissues was

within the acceptance limits of OECD 431 (lower acceptance limit ≥0.8 and upper acceptance

limit <_ 2.8) and the laboratory historical control data range. In the range of 20 - 100%

viability the Coefficient of Variation between tissue replicates was <_ 15%, indicating that the

test system functioned properly.

Skin corrosion is expressed as the remaining cell viability after exposure to the test item. The

relative mean tissue viability obtained after 3-minute and 1-hour treatments with

PF-07085579 compared to the negative control tissues was 102% and 87%, respectively.

Because the mean relative tissue viability for  PF-07085579 was not below 50% after the

3-minute treatment and not below 15% after the 1-hour treatment  PF-07085579 is considered

to be not corrosive.

In conclusion,  PF-07085579 is not corrosive in the in vitro skin corrosion test under the

experimental conditions described in this report.