DESIGNED SIRPα VARIANTS AND METHODS OF THEIR USE

RU2024119090A3Pending Publication Date: 2026-06-30FBD BIOLOGICS LTD

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Patent Information

Authority / Receiving Office: RU · RU
Patent Type: Applications
Current Assignee / Owner: FBD BIOLOGICS LTD
Filing Date: 2022-12-09
Publication Date: 2026-06-30

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Claims

1. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1, wherein the engineered SIRPα polypeptide comprises one or more amino acid mutations in the BC loop, the CD loop, and / or the DE loop.

2. The engineered SIRPα polypeptide of claim 1, comprising one or more of the following: the amino acid corresponding to E54 of SEQ ID NO: 1 is A, H, N, I, R, G, S, D or L; the amino acid that corresponds to G55 of SEQ ID NO: 1 is W, F, Q, L, D, K, R, A or P; and the amino acid that corresponds to H56 of SEQ ID NO: 1 is P, I, T, N, V, R, L, S, G or Q.

3. The engineered SIRPα polypeptide of claim 1 or 2, wherein the amino acid that corresponds to H56 of SEQ ID NO: 1 is I, T, N, V, L, S, G, or Q.

4. The engineered SIRPα polypeptide of any one of claims 1-3, wherein the amino acid that corresponds to I31 of SEQ ID NO: 1 is W, K, Y, L, A, N, or T.

5. The engineered SIRPα polypeptide of claim 4, wherein the amino acid that corresponds to I31 of SEQ ID NO: 1 is W, K, Y, L, A, or N.

6. An engineered SIRPα polypeptide according to any one of claims 1-5, comprising one or more of the following: the amino acid that corresponds to S66 of SEQ ID NO: 1 is Q or N; and the amino acid that corresponds to T67 of SEQ ID NO: 1 is G.

7. An engineered SIRPα polypeptide according to any one of claims 1-6, comprising one or more of the following: the amino acid that corresponds to H24 of SEQ ID NO: 1 is N or T; and the amino acid that corresponds to T26 of SEQ ID NO: 1 is I.

8. An engineered SIRPα polypeptide according to any one of claims 1-7, comprising one or more of the following: the amino acid that corresponds to E70 of SEQ ID NO: 1 is G, F, R, A, L or T; the amino acid that corresponds to M72 of SEQ ID NO: 1 is R or Y; and the amino acid that corresponds to D73 of SEQ ID NO: 1 is I.

9. The engineered SIRPα polypeptide of any one of claims 1-8, wherein the amino acid that corresponds to K53 of SEQ ID NO: 1 is R.

10. The engineered SIRPα polypeptide of any one of claims 1-8, wherein the amino acid that corresponds to K53 of SEQ ID NO: 1 is not R.

11. An engineered SIRPα polypeptide according to any one of claims 1-10, comprising one or more of the following: the amino acid corresponding to position 27 of SEQ ID NO: 1 is V or L; the amino acid that corresponds to position 63 of SEQ ID NO: 1 is V; and the amino acid that corresponds to position 68 of SEQ ID NO: 1 is K.

12. The engineered SIRPα polypeptide of any one of claims 1-11, comprising an amino acid sequence that is at least 85%, 90%, 95%, or 100% identical to SEQ ID NO: 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, or 45.

13. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 2, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to I31 of SEQ ID NO: 1 is W; the amino acid that corresponds to E54 of SEQ ID NO: 1 is A; the amino acid that corresponds to G55 of SEQ ID NO: 1 is W; and the amino acid that corresponds to H56 of SEQ ID NO: 1 is P.

14. The engineered SIRPα polypeptide of claim 13, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

2.

15. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 3, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to H24 of SEQ ID NO: 1 is R; the amino acid that corresponds to I31 of SEQ ID NO: 1 is W; the amino acid that corresponds to E54 of SEQ ID NO: 1 is A; the amino acid that corresponds to G55 of SEQ ID NO: 1 is F; the amino acid that corresponds to H56 of SEQ ID NO: 1 is I; and the amino acid that corresponds to E70 of SEQ ID NO: 1 is G.

16. The engineered SIRPα polypeptide of claim 15, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

3.

17. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 4, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to H24 of SEQ ID NO: 1 is N; the amino acid corresponding to E54 of SEQ ID NO: 1 is H; the amino acid that corresponds to G55 of SEQ ID NO: 1 is Q; the amino acid that corresponds to H56 of SEQ ID NO: 1 is T; the amino acid that corresponds to S66 of SEQ ID NO: 1 is Q; and the amino acid that corresponds to M72 of SEQ ID NO: 1 is R.

18. The engineered SIRPα polypeptide of claim 17, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

4.

19. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 5, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to E54 of SEQ ID NO: 1 is N; the amino acid that corresponds to G55 of SEQ ID NO: 1 is L; the amino acid that corresponds to H56 of SEQ ID NO: 1 is I; and the amino acid that corresponds to T67 of SEQ ID NO: 1 is G.

20. The engineered SIRPα polypeptide of claim 19, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

5.

21. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 6, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to T26 of SEQ ID NO: 1 is I; the amino acid corresponding to E54 of SEQ ID NO: 1 is I; the amino acid that corresponds to G55 of SEQ ID NO: 1 is L; the amino acid that corresponds to H56 of SEQ ID NO: 1 is T; and the amino acid that corresponds to M72 of SEQ ID NO: 1 is Y.

22. The engineered SIRPα polypeptide of claim 21, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

6.

23. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 7, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to I31 of SEQ ID NO: 1 is K; the amino acid corresponding to E54 of SEQ ID NO: 1 is R; the amino acid that corresponds to G55 of SEQ ID NO: 1 is D; the amino acid that corresponds to H56 of SEQ ID NO: 1 is T; and the amino acid that corresponds to M72 of SEQ ID NO: 1 is R.

24. The engineered SIRPα polypeptide of claim 23, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

7.

25. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 8, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to H24 of SEQ ID NO: 1 is T; the amino acid that corresponds to I31 of SEQ ID NO: 1 is W; the amino acid that corresponds to E54 of SEQ ID NO: 1 is G; the amino acid that corresponds to G55 of SEQ ID NO: 1 is Q; the amino acid that corresponds to H56 of SEQ ID NO: 1 is N; and the amino acid that corresponds to E70 of SEQ ID NO: 1 is F.

26. The engineered SIRPα polypeptide of claim 25, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

8.

27. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 9, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to H24 of SEQ ID NO: 1 is T; the amino acid that corresponds to I31 of SEQ ID NO: 1 is Y; the amino acid corresponding to E54 of SEQ ID NO: 1 is R; the amino acid that corresponds to G55 of SEQ ID NO: 1 is Q; the amino acid that corresponds to H56 of SEQ ID NO: 1 is T; and the amino acid that corresponds to E70 of SEQ ID NO: 1 is F.

28. The engineered SIRPα polypeptide of claim 27, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

9.

29. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 10, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to I31 of SEQ ID NO: 1 is L; the amino acid corresponding to E54 of SEQ ID NO: 1 is S; the amino acid that corresponds to G55 of SEQ ID NO: 1 is K; the amino acid that corresponds to H56 of SEQ ID NO: 1 is V; and the amino acid that corresponds to E70 of SEQ ID NO: 1 is R.

30. The engineered SIRPα polypeptide of claim 29, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

10.

31. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 11, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to I31 of SEQ ID NO: 1 is Y; the amino acid that corresponds to E54 of SEQ ID NO: 1 is G; the amino acid that corresponds to G55 of SEQ ID NO: 1 is R; the amino acid that corresponds to H56 of SEQ ID NO: 1 is R; and the amino acid that corresponds to E70 of SEQ ID NO: 1 is A.

32. The engineered SIRPα polypeptide of claim 31, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

11.

33. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 12, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to I31 of SEQ ID NO: 1 is L; the amino acid that corresponds to E54 of SEQ ID NO: 1 is D; the amino acid that corresponds to G55 of SEQ ID NO: 1 is F; the amino acid that corresponds to H56 of SEQ ID NO: 1 is L; and the amino acid that corresponds to M72 of SEQ ID NO: 1 is R.

34. The engineered SIRPα polypeptide of claim 33, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

12.

35. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 13, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to I31 of SEQ ID NO: 1 is A; the amino acid corresponding to E54 of SEQ ID NO: 1 is L; the amino acid that corresponds to G55 of SEQ ID NO: 1 is D; the amino acid that corresponds to H5 6 of SEQ ID NO: 1 is S; and the amino acid that corresponds to N71 of SEQ ID NO: 1 is S.

36. The engineered SIRPα polypeptide of claim 35, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

13.

37. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 14, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to H24 of SEQ ID NO: 1 is R; the amino acid that corresponds to I31 of SEQ ID NO: 1 is T; the amino acid that corresponds to E54 of SEQ ID NO: 1 is A; the amino acid that corresponds to G55 of SEQ ID NO: 1 is K; the amino acid that corresponds to H56 of SEQ ID NO: 1 is Q; and the amino acid that corresponds to D73 of SEQ ID NO: 1 is I.

38. The engineered SIRPα polypeptide of claim 37, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

14.

39. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 33, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to H24 of SEQ ID NO: 1 is T; the amino acid corresponding to E54 of SEQ ID NO: 1 is R; the amino acid that corresponds to G55 of SEQ ID NO: 1 is A; and the amino acid that corresponds to H56 of SEQ ID NO: 1 is P.

40. The engineered SIRPα polypeptide of claim 39, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

33.

41. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 34, wherein the polypeptide comprises one or more of the following: the amino acid corresponding to E54 of SEQ ID NO: 1 is S; the amino acid that corresponds to G55 of SEQ ID NO: 1 is P; the amino acid that corresponds to H56 of SEQ ID NO: 1 is P; and the amino acid that corresponds to E70 of SEQ ID NO: 1 is L.

42. The engineered SIRPα polypeptide of claim 41, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

34.

43. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 35, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to H24 of SEQ ID NO: 1 is T; the amino acid that corresponds to I31 of SEQ ID NO: 1 is W; the amino acid corresponding to E54 of SEQ ID NO: 1 is S; the amino acid that corresponds to H56 of SEQ ID NO: 1 is P; and the amino acid that corresponds to E70 of SEQ ID NO: 1 is R.

44. The engineered SIRPα polypeptide of claim 43, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

34.

45. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 36, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to I31 of SEQ ID NO: 1 is W; the amino acid corresponding to E54 of SEQ ID NO: 1 is R; the amino acid that corresponds to G55 of SEQ ID NO: 1 is A; the amino acid that corresponds to H56 of SEQ ID NO: 1 is G; and the amino acid that corresponds to E70 of SEQ ID NO: 1 is T.

46. The engineered SIRPα polypeptide of claim 45, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

36.

47. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 37, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to S29 of SEQ ID NO: 1 is Q; the amino acid corresponding to E54 of SEQ ID NO: 1 is H; the amino acid that corresponds to G55 of SEQ ID NO: 1 is R; the amino acid that corresponds to H56 of SEQ ID NO: 1 is T; and the amino acid that corresponds to S66 of SEQ ID NO: 1 is N.

48. The engineered SIRPα polypeptide of claim 47, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

37.

49. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 38, wherein the polypeptide comprises one or more of the following: the amino acid corresponding to E54 of SEQ ID NO: 1 is S; the amino acid that corresponds to G55 of SEQ ID NO: 1 is P; the amino acid that corresponds to H56 of SEQ ID NO: 1 is R; and the amino acid that corresponds to E70 of SEQ ID NO: 1 is L.

50. The engineered SIRPα polypeptide of claim 49, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

38.

51. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 39, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to V27 of SEQ ID NO: 1 is L; the amino acid that corresponds to G55 of SEQ ID NO: 1 is D; the amino acid that corresponds to H56 of SEQ ID NO: 1 is R; and the amino acid that corresponds to M72 of SEQ ID NO: 1 is R.

52. The engineered SIRPα polypeptide of claim 51, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

39.

53. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 40, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to V27 of SEQ ID NO: 1 is L; the amino acid that corresponds to I31 of SEQ ID NO: 1 is T; the amino acid that corresponds to H56 of SEQ ID NO: 1 is P; and the amino acid that corresponds to E70 of SEQ ID NO: 1 is G.

54. The engineered SIRPα polypeptide of claim 53, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

40.

55. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 41, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to H24 of SEQ ID NO: 1 is T; the amino acid that corresponds to I31 of SEQ ID NO: 1 is Y; the amino acid corresponding to E54 of SEQ ID NO: 1 is R; the amino acid that corresponds to G55 of SEQ ID NO: 1 is Q; and the amino acid that corresponds to H56 of SEQ ID NO: 1 is T.

56. The engineered SIRPα polypeptide of claim 55, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

41.

57. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 42, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to H24 of SEQ ID NO: 1 is T; the amino acid that corresponds to I31 of SEQ ID NO: 1 is N; the amino acid corresponding to E54 of SEQ ID NO: 1 is R; the amino acid that corresponds to G55 of SEQ ID NO: 1 is Q; and the amino acid that corresponds to H56 of SEQ ID NO: 1 is T.

58. The engineered SIRPα polypeptide of claim 57, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

42.

59. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 43, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to H24 of SEQ ID NO: 1 is R; the amino acid that corresponds to I31 of SEQ ID NO: 1 is Y; the amino acid that corresponds to E54 of SEQ ID NO: 1 is A; the amino acid that corresponds to G55 of SEQ ID NO: 1 is K; and the amino acid that corresponds to H56 of SEQ ID NO: 1 is Q.

60. The engineered SIRPα polypeptide of claim 59, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

43.

61. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 44, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to H24 of SEQ ID NO: 1 is R; the amino acid that corresponds to I31 of SEQ ID NO: 1 is N; the amino acid that corresponds to E54 of SEQ ID NO: 1 is A; the amino acid that corresponds to G55 of SEQ ID NO: 1 is K; and the amino acid that corresponds to H56 of SEQ ID NO: 1 is Q.

62. The engineered SIRPα polypeptide of claim 61, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

44.

63. An engineered SIRPα polypeptide comprising an amino acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 45, wherein the polypeptide comprises one or more of the following: the amino acid that corresponds to H24 of SEQ ID NO: 1 is R; the amino acid that corresponds to E54 of SEQ ID NO: 1 is A; the amino acid that corresponds to G55 of SEQ ID NO: 1 is K; and the amino acid that corresponds to H56 of SEQ ID NO: 1 is Q.

64. The engineered SIRPα polypeptide of claim 63, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:

45.

65. An engineered SIRPα polypeptide according to any one of claims 1-64, characterized in that it further comprises a CH2 domain and a CH3 domain.

66. The engineered SIRPα polypeptide of claim 65, further comprising a hinge region.

67. The engineered SIRPα polypeptide of claim 65, wherein the CH2 domain is an IgG CH2 domain and the CH3 domain is an IgG CH3 domain.

68. The engineered SIRPα polypeptide of claim 65, wherein the engineered SIRPα polypeptide comprises an amino acid sequence that is at least 80%, 85%, 90%, or 95% identical to any one of SEQ ID NOs: 15-28 and 46-58.

69. A protein construct comprising an engineered SIRPα polypeptide according to any one of claims 1-68.

70. The protein construct according to claim 69, comprising two or more engineered SIRPα polypeptides.

71. The protein construct of claim 70, wherein at least two constructed SIRPα polypeptides are identical.

72. The protein construct according to claim 70, characterized in that at least two constructed SIRPα polypeptides are different.

73. The protein construct according to claim 69, further comprising an Fc region.

74. The protein construct according to claim 73, characterized in that the Fc region is the Fc region of IgG4.

75. The protein construct according to claim 73, characterized in that the Fc region is the Fc region of IgG1 (for example, with LALA mutations or LALA-PG mutations).

76. A protein construct containing a first fusion polypeptide comprising the engineered SIRPα polypeptide of any one of claims 1-68, a first CH2 domain and a first CH3 domain; and a second fusion polypeptide comprising a second CH2 domain and a second CH3 domain; wherein the first fusion polypeptide and the second fusion polypeptide bind to each other to form a dimer.

77. The protein construct of claim 76, wherein the second fusion polypeptide further comprises a second engineered SIRPα polypeptide.

78. A pharmaceutical composition comprising an engineered SIRPα polypeptide according to any one of claims 1-68 or a protein construct according to any one of claims 69-77; and a pharmaceutically acceptable carrier.

79. A nucleic acid encoding an engineered SIRPα polypeptide according to any one of claims 1-68 or a protein construct according to any one of claims 69-77.

80. A vector containing a nucleic acid according to claim 79.

81. A cell containing a nucleic acid according to claim 79.

82. The cell according to claim 81, characterized in that it is a CHO cell.

83. A method for producing an engineered SIRPα polypeptide or a protein construct containing the engineered SIRPα polypeptide, comprising culturing the cell according to paragraph 81 or 82 under conditions sufficient for the cell to produce an engineered SIRPα polypeptide or protein construct; and assembly of an engineered SIRPα polypeptide or a protein construct produced by a cell.

84. A method of treating a subject suffering from cancer, comprising administering to the subject a therapeutically effective amount of a composition comprising an engineered SIRPα polypeptide according to any one of claims 1-68 or a protein construct according to any one of claims 69-77.

85. The method according to claim 84, characterized in that the subject has a solid tumor or hematological cancer.

86. The method according to claim 84, wherein the cancer is acute myeloid leukemia, non-Hodgkin's lymphoma, breast cancer, bladder cancer, ovarian cancer, or small cell lung cancer.

87. A method for reducing the rate of tumor growth, comprising contacting a tumor cell with an effective amount of a composition comprising the engineered SIRPα polypeptide of any one of claims 1-68 or the protein construct of any one of claims 69-77.

88. A method for killing a tumor cell, comprising contacting the tumor cell with an effective amount of a composition comprising the engineered SIRPα polypeptide of any one of claims 1-68 or the protein construct of any one of claims 69-77.