Agonistic cd28 antigen binding molecules targeting her2

A bispecific agonistic CD28 antigen binding molecule characterized by monovalent binding to CD28, comprising

• (a) a first antigen binding domain capable of specific binding to CD28,
• (b) a second antigen binding domain capable of specific binding to an antigen binding domain capable of specific binding to human epidermal growth factor receptor-2 (Her2), and
• (c) a Fc domain composed of a first and a second subunit capable of stable association comprising one or more amino acid substitution that reduces the binding affinity of the antigen binding molecule to an Fc receptor and/or effector function,
• wherein said second antigen binding domain capable of specific binding to Her2 comprises
• (i) a heavy chain variable region (VHHer2) comprising a heavy chain complementary determining region CDR-H1 of SEQ ID NO:
• 2, a CDR-H2 of SEQ ID NO:
• 3, and a CDR-H3 of SEQ ID NO:
• 4, and a light chain variable region (VLHer2) comprising a light chain complementary determining region CDR-L1 of SEQ ID NO:
• 5, a CDR-L2 of SEQ ID NO:
• 6 and a CDR-L3 of SEQ ID NO:
• 7;
• or
• (ii) a heavy chain variable region (VHHer2) comprising a heavy chain complementary determining region CDR-H1 of SEQ ID NO:
• 10, a CDR-H2 of SEQ ID NO:
• 11, and a CDR-H3 of SEQ ID NO:
• 12, and a light chain variable region (VLHer2) comprising a light chain complementary determining region CDR-L1 of SEQ ID NO:
• 13, a CDR-L2 of SEQ ID NO:
• 14 and a CDR-L3 of SEQ ID NO:
• 15;
• or
• (iii) a heavy chain variable region (VHHer2) comprising a heavy chain complementary determining region CDR-H1 of SEQ ID NO:
• 132, a CDR-H2 of SEQ ID NO:
• 133, and a CDR-H3 of SEQ ID NO:
• 134, and a light chain variable region (VLHer2) comprising a light chain complementary determining region CDR-L1 of SEQ ID NO:
• 135, a CDR-L2 of SEQ ID NO:
• 136 and a CDR-L3 of SEQ ID NO:
• 137, or
• (iv) a heavy chain variable region (VHHer2) comprising a heavy chain complementary determining region CDR-H1 of SEQ ID NO:
• 140, a CDR-H2 of SEQ ID NO:
• 141, and a CDR-H3 of SEQ ID NO:
• 142, and a light chain variable region (VLHer2) comprising a light chain complementary determining region CDR-L1 of SEQ ID NO:
• 143, a CDR-L2 of SEQ ID NO:
• 144 and a CDR-L3 of SEQ ID NO:
• 145.