N-((3R,6S)-6-methylpiperidin-3-yl)-7H-pyrrolo[2,3-d]pyrimidin-4-amine

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

31st January 2020 to 28th February 2020

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2020

Report date:

2020

Materials and methods

Test guideline

Test guideline 1

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.40BIS:"In Vitro Skin Corrosion: Human Skin Model Test". Official Journal of the European Union No. L142, 31 May 2008.

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 431 (In Vitro Skin Corrosion: Reconstructed Human Epidermis (RHE) Test Method)

GLP compliance:

yes

Test material

Test material information

1

Reference substance name:

Reference substance 001

Cas Number:

2374827-92-4

Test material form:

solid: particulate/powder

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

other: human-derived epidermal keratinocytes

Cell source:

other: Not specified

Vehicle:

unchanged (no vehicle)

Details on test system:

EpiDerm Skin Model (EPI-200, Lot no.: 32177 kits H and I.
The model consists of normal, human-derived epidermal keratinocytes which have been cultured to form a multilayered, highly differentiated model of the human epidermis. It consists of organized basal, spinous and granular layers, and a multi-layered stratum corneum containing intercellular lamellar lipid layers arranged in patterns analogous to those found in vivo. The EpiDerm tissues (surface 0.6 cm2) were cultured on polycarbonate membranes of 10 mm cell culture inserts.

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

The test was performed on a total of 4 tissues per test item.
31.62 to 36.99 mg of the solid test item was added into the 6-well plates on top of the skin tissues for both the 3-minute and 1-hour time point.

2 tissues were treated with 50 µL Milli-Q water (negative control) and 2 tissues were treated with 50 µL 8N KOH (positive control) for both the 3-minute and 1-hour time point.

Duration of treatment / exposure:

3 minutes and 1 hour

Duration of post-treatment incubation (if applicable):

3 hours at 37°C in air containing 5% CO2

Number of replicates:

4

Test system

Details on study design:

The test is based on the experience that corrosive chemicals show cytotoxic effects following short-term exposure to the stratum corneum of the epidermis. The test is designed to predict
and classify the skin corrosion potential of a test item by assessment of its effect on a three dimensional human epidermis model.
The test consists of topical application of PF-06715298 on the skin tissue for 3-minute and 1-hour. After exposure the skin tissue is thoroughly rinsed to remove the test item followed by immediate determination of the cytotoxic (corrosive) effect.
Cytotoxicity is expressed as the reduction of mitochondrial dehydrogenase activity measured by formazan production from 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) at the end of the treatment.

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Exposure duration 3 minutes

Value:

98

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Results 2

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Exposure duration 1 hour

Value:

86

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

PF-06715298 is not corrosive in the in vitro skin corrosion test under the experimental conditions described in this report.

Executive summary:

The objective of this study was to evaluatePF-06715298 for its ability to induce skin corrosion on a human three dimensional epidermal model (EpiDerm (EPI-200)). The possible corrosive potential of the test item 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.
Batch 902/6651600/C/21/1 of the test item was a white powder. Skin tissue was moistened with 25 µL of Milli-Q water and at least 25 mg of the test item was applied directly on top of the skin tissue.
The positive control had a mean relative tissue viability of 13% after the 1-hour exposure.
The absolute mean OD570 (optical density at 570nm)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 the test item compared to the negative control tissues was 98% and 86%, respectively. Because the mean relative tissue viability for the test item was not below 50% after the 3-minute treatment and not below 15% after the 1-hour treatment, the test item is considered to be not corrosive.
In conclusion, PF-06715298 is not corrosive in the in vitro skin corrosion test under the experimental conditions described in this report.