Table 1.
Catabolites of [3H]-MMAE-polatuzumab vedotin identified in the Sprague Dawley rats.
| Catabolite | Protonated Molecular Formula |
Theoretical m/z for [M+H]+ |
Measured m/z for [M+H]+,b |
Mass Accuracy (ppm) | %ID in Bile | %ID in Urine |
|---|---|---|---|---|---|---|
| C1 | NA | NA | NA | NA | 2.26 | |
| C2 | C32H55N4O6+ | 591.4116 | 591.4110 | −1.12 | 3.94 | NA |
| C3 | C37H64N5O8+ | 706.4749 | 706.4749 | −0.13 | 9.32 | NA |
| C4 | C38H66N5O7+ | 704.4957 | 704.4958 | 0.16 | 13.49 | NA |
| C5 | C33H57N4O6+ | 605.4273 | 605.4264 | −1.44 | 12.16 c | NA |
| C6 | C38H66N5O8+ | 720.4906 | 720.4905 | −0.15 | ||
| C7 | C39H68N5O7+ | 718.5113 | 718.5112 | −0.22 | 16.48 d | 2.56 d |
| C8 | C71H114N12O17S2+ | 719.4067 a | 719.4047 a | −2.88 | 2.60 | NA |
ID: injected dose; NA: not applicable. a C8 m/z corresponds to the doubly charged species. b The m/z values reported for MMAE and its catabolites were from the most abundant ion incorporating one 3H. c Catabolites C5 and C6 shared the same retention time. Therefore, the combined total %ID of catabolites C5 and C6 is listed in the table. d Catabolite C7 was detected in three matrices: plasma, bile, and urine. The detected amount of C7 in the plasma was too low to calculate a percentage of the ID.