1. in your experience, do targeted protein degraders obey the free drug hypothesis at a practical time scale with a normal dosing regimen?
2. When there is a disconnect from the free drug hypothesis, have in vitro assay lC50/EC50 values also been corrected for protein binding?
3. Has an explanation been identified for the disconnect?
4. Are you developing targeted protein degraders for the oral route of administration?
5. What formulation strategies have you used most often and/or have been most successful for initial in vivo PK studies using the oral route of administration for targeted protein degraders at each stage of development? Select all that apply.
6. In your experience, what polar surface area (PSA) is most likely to result in an orally bioavailable targeted protein degrader?
7. In your experience, what LogD (pH 7.4) is most likely to result in an orally bioavailable (>30% F) targeted protein degrader?
8. In your experience, what molecular weight is most likely to result in an orally bioavallable targeted protein degrader?
9. ln your experience, what solubility (uM) at pH 7.4 is most likely to result in an orally bioavailable targeted protein degrader?
10. In your experience, how many H-bond acceptors are most likely to result in a successful oral targeted
11. In your experience, how many H-bond donors are most likely to result in a successful oral targeted
12. ln your experience, how many rotatable bonds are most likely to result in an orally bioavailable targeted protein degrader?
13. What other properties do you consider when developing an orally bioavailable (>30% F) targeted protein
14. What are the top 1 or 2 ADME/physical property challenges you encounter when developing a targeted
protein degrader with good oral PK (>30% F)?
15. Would your property range answers differ for a successful intravenous targeted protein degrader?
16. How would property ranges differ for intravenous compared with oral degraders?
17. ls your ADME assessment of targeted protein degraders different from standard small molecules with poor
physico-chemical properties (i.e., that break the Rule of 5)?
18. What are the most significant changes you have made to the ADM assessment assays?
19. Please briefly describe the general principles of new assays that you have successfully used.
20 have you modified your DDI assessment due to the potential degradation of enzymes/transporters?
21. Are there any unique protein degrader properties that influence your species selection for in vivo ADME and PK studies?
22. Are your strategies to predict human PK for targeted protein degraders different than traditional small molecules?
23. what strategics do you use for huam PK prediction of target protein degrader?
24. In your experience, do standard preclinical PK prediction methods (e.g., in vitro to in vivo extrapolation[IVIVE]) work as well for targeted protein degraders as for typical small molecules?
25. If no, what is the suspected or known cause of discrepancies?
26. Have you assessed the potential for lymphatic absorption of targeted protein degraders?
27. Have you used intravenous dosing for targeted protein degraders?
28. what issues were observed with IV dosing?
29. Have you used subcutaneous dosing for targeted protein degraders?
30. what issues were observed with SC dosing?
31. ls there any unique pharmacological impact of the metabolites of targeted protein degraders?
32 what unique observations were noted?
33. What major clearance mechanism(s) have you observed with targeted protein degraders? Select all that apply.
34. Do you have experience with targeted protein degraders that cross the blood-brain barrier?
35. What is the range of observed unbound Kp (brain:plasma) values of these BBB crossingdegraders?
36. Have you observed any limitations to distribution besides the BBB for targeted protein degraders?
37. Please describe other tissues in which you have observedlimitations.
38. What method(s) do you use most often to measure target protein resynthesis?
39. Have you modified your in vitro ADME assays (e.g, solubility, plasma protein binding, permeability, intrinsicclearance, etc.) to improve data quality (e.g., accuracy, reproducibility, etc.) for targeted protein degraders?
40. Briefly describe the general modifications that have been made to assays (ie, no need to provide % modifiervalues or specific times).
41. In your experience, what plasma protein binding range(s) do targeted protein degraders fall within? Selectall that apply
42. Please rank the plasma protein binding ranges from most common bound to least common bound that mosttargeted protein degraders fall within
43. Are your methods for measuring plasma protein binding for targeted protein degraders different thantraditional small molecules?
44. What method(s) do you use most often to measure plasma protein binding for targeted protein degraders?
45. What is/are your top challenge(s) to accurately measuring plasma protein binding for targeted proteindegraders?
46. Have you experienced epimerization/racemization with targeted protein degraders?
47. Did vou handle epimerization/racemization of targeted protein decraders differently than vou would have foia standard small molecule?
48. What did you do differently for targeted proteindegraders?
49. In your experience, do the properties of a targeted protein degrader's individual structural parts (i.e., targetprotein ligand, linker, or E3 ligase ligand) dictate the overall properties (e.g., permeability, intrinsic clearanceetc.) of the whole (intact) degrader (i.e., have you established a correlation between parts and properties)?
50. What properties have you optimized on the parts?
51. Do you have examples of parts having poor properties, but the whole (intact) degrader having improvedproperties and/or oral PK?
52. Did optimization of the linker cause the improved properties for the whole (intact) degrader?
53. What ranges) of target protein resynthesis rates have you most often observed for targeted proteindegrader targets?
54. Do you consider ADME concerns and/or drug-ability when selecting an E3 ligase?
55. If not ADME concerns and/or drug-ability, what quality do you use to drive ligases election?
56. Approximately how many in vivo efficacy studies (e.g., PK/PD, tumor growth inhibition, etc,) have you run with targeted protein degraders?
57. How many examples of the hook effect have you observed during in vivo efficacy studies (e.g., PK/PDtumor growth inhibition, etc.)?
58. Were unbound plasma concentrations measured to confirm the hook effect during in vivo eficacy studies?
59. Were unbound concentrations in the target tissue measured to confirm the hook effect during in vivoefficacy studies?
60. What interpretations were impacted by the observation of the hook effect in vivo? Select all that apply
61. How much experience have you had with in silico/machine learning prediction of targeted protein degrader ADME properties?
62. In your extensive experience, have in silico tools accurately predicted the ADME properties of targetedprotein degraders?
63. How much experience have you had with PBPK prediction of PK for targeted protein degraders?
64. In your extensive experience, have PBPK tools (e.g., SimCYP, GastroPlus, etc,) accurately predicted thePK of targeted protein degraders?