5,5'-dithiodi-1,3,4-thiadiazole-2(3H)-thione

Basic toxicokinetics

Administrative data

Endpoint:

basic toxicokinetics, other

Remarks:

in silico

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

See enclosed files

Data source

Reference

Reference 1

Reference Type:

publication

Title:

pkCSM: predicting small-molecule pharmacokinetic properties using graph-based signatures

Author:

Pires DEV, Blundell TL and Ascher DB

Year:

2015

Bibliographic source:

Journal of Medicinal Chemistry, 58 (9):4066–4072

Reference 2

Reference Type:

other: web site

Title:

Unnamed

Year:

2018

Materials and methods

Objective of study:

absorption

distribution

excretion

metabolism

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: REACH Guidance on QSARs R.6

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: REACH Guidance on IR&CSA, Chapter R.14, Occupational exposure assessment Update to change the scope of the guidance from exposure estimation to exposure assessment

Version / remarks:

August 2016

Principles of method if other than guideline:

pkCSM uses graph-based signatures to develop predictive models of central ADME properties. pkCSM performs as well or better than current methods.

Test material

Test material information

Constituent 1

Reference substance name:

5,5'-dithiodi-1,3,4-thiadiazole-2(3H)-thione

EC Number:

276-763-0

EC Name:

5,5'-dithiodi-1,3,4-thiadiazole-2(3H)-thione

Cas Number:

72676-55-2

Molecular formula:

C4-H2-N4-S6

IUPAC Name:

5,5'-dithiodi-1,3,4-thiadiazole-2(3H)-thione

Specific details on test material used for the study:

SMILES: S=C1NN=C(SSC2=NNC(=S)S2)S1

Results and discussion

Main ADME results

Main ADME results 1

Type:

absorption

Results:

Intestinal absorption (human): 88.38%

Main ADME results 2

Type:

distribution

Results:

VDss (human) (log L/kg): 0.044

Main ADME results 3

Type:

distribution

Results:

Fraction unbound (human) : 0.634

Main ADME results 4

Type:

distribution

Results:

BBB permeability (log BB): 0.242

Main ADME results 5

Type:

distribution

Results:

CNS permeability (log PS): -3.911

Main ADME results 6

Type:

excretion

Results:

Renal OCT2 substrate: no

Main ADME results 7

Type:

excretion

Results:

Total Clearance (log ml/min/kg): -0.268

Toxicokinetic / pharmacokinetic studies

Details on absorption:

According to the model "Intestinal absorption (human)", 88.38% of the substance is absorbed after oral exposure.

Details on distribution in tissues:

According to the model "VDss (human)", the volume of distribution (VD, i.e. theoritical volume that the total dose of a drug would need to be uniformly distributed to give the same concentration as in blood plasma) is moderate (Log between -0.15 and 0.45).
According to the model "Fraction unbound (human)", 63.4 % of the absorbed dose is unbound in the plasma.
According to the model "BBB permeability", the substance is moderately cross the blood-brain barrier (0.1 < Log BB < 0.3).
According to the model "CNS permeability",the substance is unable to penetrate the CNS (log PS <-3).

Details on excretion:

According to the model "Renal OCT2 substrate", the substance is not a OCT2 substrate. The substance is not transported by this renal transporter.
According to the model "Total clearance" , the predicted total clearance (hepatic & renal clearance) is of 0.54 ml/min/kg (log(ml/min/kg) -0.268) corresponding to the very low clearance (below 6 ml/min/kg).

Metabolite characterisation studies

Metabolites identified:

no

Any other information on results incl. tables

Property	Model Name	Predicted Value	Unit
Absorption	Water solubility	-3.55	Numeric (log mol/L)
Absorption	Caco2 permeability	1.324	Numeric (log Papp in 10^-6cm/s)
Absorption	Intestinal absorption (human)	88.382	Numeric (% Absorbed)
Absorption	Skin Permeability	-2.753	Numeric (log Kp)
Absorption	P-glycoprotein substrate	No	Categorical (Yes/No)
Absorption	P-glycoprotein I inhibitor	No	Categorical (Yes/No)
Absorption	P-glycoprotein II inhibitor	No	Categorical (Yes/No)
Distribution	VDss (human)	0.044	Numeric (log L/kg)
Distribution	Fraction unbound (human)	0.634	Numeric (Fu)
Distribution	BBB permeability	0.242	Numeric (log BB)
Distribution	CNS permeability	-3.911	Numeric (log PS)
Metabolism	CYP2D6 substrate	No	Categorical (Yes/No)
Metabolism	CYP3A4 substrate	No	Categorical (Yes/No)
Metabolism	CYP1A2 inhibitior	YES	Categorical (Yes/No)
Metabolism	CYP2C19 inhibitior	No	Categorical (Yes/No)
Metabolism	CYP2C9 inhibitior	No	Categorical (Yes/No)
Metabolism	CYP2D6 inhibitior	No	Categorical (Yes/No)
Metabolism	CYP3A4 inhibitior	No	Categorical (Yes/No)
Excretion	Total Clearance	-0.268	Numeric (log ml/min/kg)
Excretion	Renal OCT2 substrate	No	Categorical (Yes/No)

Applicant's summary and conclusion

Conclusions:

According to the QSAR pkCSM, the substance is well absorbed by oral route (88.38%), and well distributed into the body. Moreover, no hepatic and renal clearance is expected.