SpeciesAccepted
Teplizumab tested only in a single-dose chimpanzee study; repeat-dose and DART studies used a mouse surrogate anti-CD3 antibody
Why: No cross-reactivity except human, gorilla, chimpanzee and gibbon; no other relevant species · No relevant species · Within the guideline
“Lack of cross-reactivity with other species than human, gorilla, chimpanzee and gibbon was confirmed in silico, and it is therefore agreed that, in addition to chimpanzee, no relevant species for further non-clinical testing of teplizumab are available.”
✓ VerifiedEMA assessment report, p. 46Source ↗ Study lengthAcceptedBeyond the letter
No chronic toxicity study with the surrogate; the study that would have covered it was interrupted
Why: No target organ of toxicity in either species; comparable PD of teplizumab and surrogate · Weight of evidence · Pharmacology or kinetics
“No chronic studies with the surrogate were conducted in accordance with the ICH S6 (R1) guideline. The interrupted study 8233170 would have covered this requirement.”
✓ VerifiedEMA assessment report, p. 42Source ↗ “Considering the absence of target organ for toxicity in both species and the comparable PD effect of teplizumab and the mouse surrogate on the immune cell populations, the absence of longer duration studies can be accepted.”
✓ VerifiedEMA assessment report, p. 42Source ↗ CarcinogenicityAccepted
No carcinogenicity studies for a non-oncology immunomodulator; weight-of-evidence assessment instead
Why: Weight of evidence from literature, animal and clinical data; short-term treatment schedule · Weight of evidence · Within the guideline · Human data
“Carcinogenicity The absence of carcinogenicity studies is justified by the weight of evidence approach in line with the ICH S1B (R1) and ICH S6 (R1) guidelines.”
✓ VerifiedEMA assessment report, p. 43Source ↗ “Based on the weight-of-evidence from literature and teplizumab data from animal toxicology studies and clinical trials, and considering the short-term clinical treatment schedule, the theoretical risk of carcinogenicity is considered extremely low under the conditions of the labelled dosing.”
✓ VerifiedEMA assessment report, p. 50Source ↗ Juvenile toxAcceptedBeyond the letter
No juvenile animal toxicity study
Why: No relevant species; a rodent juvenile study with the surrogate would not add value · No relevant species
“The applicant justifies the absence of an animal juvenile study based on that there is no relevant animals’ species for teplizumab for this type of study and that a rodent juvenile toxicity study with the surrogate antibody would not add any value, which is agreed.”
✓ VerifiedEMA assessment report, p. 44Source ↗