Abstract: Heterodimeric IgA Fc (IgA HetFc) constructs comprising one or more amino acid mutations in the CH3 domain that allow for formation of a heterodimeric Fc having high purity and thermostability. The IgA HetFc constructs may comprise one or more target binding domains. Higher order IgA HetFc multimers comprising multiple IgA HetFc constructs may be prepared in which two of the IgA HetFc constructs are joined by a J chain.

Abstract: The present disclosure provides fusion proteins with a multifunctional biologic design for programmed target engagement. In certain embodiments, the fusion proteins described herein provide for concurrent target antigen engagement and immune checkpoint or costimulatory receptor targeting. In certain aspects, the fusion protein is masked from presenting any on-target off-tissue action (i.e., toxicity) associated with target engagements. In certain embodiments, the fusion proteins provide a masked antigen binding domain as well as a masked immunomodulatory target binding domain, such that the programmed activation of one binding functionality results in the activation of the other binding functionality as well, thereby yielding a bispecific molecule. Thus, the disclosure also provides for methods of masking and conditional activation of antigen binding domains in specific target tissue setting and targeting and activation of immunomodulatory targets without severe adverse toxicity effects.

Abstract: Described herein are antibody constructs comprising a 4- 1BB binding domain and an anti-Folate Receptor a (FRa) antigen- binding domain, wherein the 4-1BB-binding domain and the FR? antigen-binding domain are linked directly or indirectly to a scaffold. The scaffold may be an Fc construct with modifications that reduce its ability to mediate effector function. The antibody constructs are used in the treatment of a subject having cancer.

Abstract: The present disclosure relates to masked IL12 fusion proteins, compositions comprising the same and methods of using the compositions for the treatment of a variety of diseases including cancer.

Abstract: Described herein are antibody constructs comprising a 41-1BB binding domain and an antigen-binding domain that binds to a tumor-associated antigen (TAA), wherein the 4-1BB-binding domain and the TAA antigen-binding domain are linked directly or indirectly to a scaffold. The scaffold may be an Fc construct with modifications that reduce its ability to mediate effector function.

Abstract: The present invention provides heterodimer pairs that can comprise a first heterodimer and a second heterodimer wherein each heterodimer comprises an immunoglobulin heavy chain or fragment thereof and an immunoglobulin light chain or fragment thereof. At least one of the heterodimers can comprise one or more amino acid modifications in the CH1 and/or CL domains, one or more amino acid modifications in the VH and/or VL domains, or a combination thereof. The modified amino acid(s) can be part of the interface between the light chain and heavy chain and are typically modified to create preferential pairing between each heavy chain and a desired light chain such that when the two heavy chains and two light chains of the heterodimer pair are co-expressed in a cell, the heavy chain of the first heterodimer preferentially pairs with one of the light chains rather than the other. Likewise, the heavy chain of the second heterodimer typically preferentially pairs with the second light chain rather than first.

Abstract: The present invention provides heterodimer pairs that can comprise a first heterodimer and a second heterodimer wherein each heterodimer comprises an immunoglobulin heavy chain or fragment thereof and an immunoglobulin light chain or fragment thereof. At least one of the heterodimers can comprise one or more amino acid modifications in the CH1 and/or CL domains, one or more amino acid modifications in the VH and/or VL domains, or a combination thereof. The modified amino acid(s) can be part of the interface between the light chain and heavy chain and are typically modified to create preferential pairing between each heavy chain and a desired light chain such that when the two heavy chains and two light chains of the heterodimer pair are co-expressed in a cell, the heavy chain of the first heterodimer preferentially pairs with one of the light chains rather than the other. Likewise, the heavy chain of the second heterodimer typically preferentially pairs with the second light chain rather than first.

Abstract: The present invention provides heterodimer pairs that can comprise a first heterodimer and a second heterodimer wherein each heterodimer comprises an immunoglobulin heavy chain or fragment thereof and an immunoglobulin light chain or fragment thereof. At least one of the heterodimers can comprise one or more amino acid modifications in the CH1 and/or CL domains, one or more amino acid modifications in the VH and/or VL domains, or a combination thereof. The modified amino acid(s) can be part of the interface between the light chain and heavy chain and are typically modified to create preferential pairing between each heavy chain and a desired light chain such that when the two heavy chains and two light chains of the heterodimer pair are co-expressed in a cell, the heavy chain of the first heterodimer preferentially pairs with one of the light chains rather than the other. Likewise, the heavy chain of the second heterodimer typically preferentially pairs with the second light chain rather than first.

Abstract: The present invention provides heterodimer pairs that can comprise a first heterodimer and a second heterodimer wherein each heterodimer comprises an immunoglobulin heavy chain or fragment thereof and an immunoglobulin light chain or fragment thereof. At least one of the heterodimers can comprise one or more amino acid modifications in the CH1 and/or CL domains, one or more amino acid modifications in the VH and/or VL domains, or a combination thereof. The modified amino acid(s) can be part of the interface between the light chain and heavy chain and are typically modified to create preferential pairing between each heavy chain and a desired light chain such that when the two heavy chains and two light chains of the heterodimer pair are co-expressed in a cell, the heavy chain of the first heterodimer preferentially pairs with one of the light chains rather than the other. Likewise, the heavy chain of the second heterodimer typically preferentially pairs with the second light chain rather than first.

Abstract: Bispecific antigen-binding constructs e.g., antibodies conjugated to drugs (ADCs), which bind CD3 and other cell-surface target antigen such as tumor antigens e.g., CD19, CDH3, HER2, HER3 and EGFR antigens and methods of use are disclosed.

Abstract: Disclosed herein are isolated multi-specific heteromultimer constructs that bind to CD3 expressed on T-cells and to an antigen expressed on B-cells. The multi-specific heteromultimer constructs are capable of bridging T- and B-cells and mediating killing of B-cells. The multi-specific heteromultimer constructs are based on a heterodimeric Fc scaffold or on a segmented albumin scaffold. Also disclosed herein are multi-specific heteromultimer constructs that bind to HER2 and HER3.

Abstract: Provided are heterodimer pairs comprising a first heterodimer and a second heterodimer wherein each heterodimer comprises an immunoglobulin heavy chain or fragment thereof and an immunoglobulin light chain. At least one of the heterodimers comprises amino acid modifications in the CH1 and/or CL domains, amino acid modifications in the VH and/or VL domains or a combination thereof. The modified amino acid residues are part of the interface between the light chain and heavy chain and are modified in order to create preferential pairing between each heavy chain and a desired light chain such that when the two heavy chains and two light chains of the heterodimer pair are co-expressed in a mammalian cell, the heavy chain of the first heterodimer preferentially pairs with one of the light chains rather than the other. Likewise, the heavy chain of the second heterodimer preferentially pairs with the second light chain rather than first.

Abstract: The provided scaffolds have heavy chains that are asymmetric in the various domains (e.g. CH2 and CH3) to accomplish selectivity between the various Fc receptors involved in modulating effector function, beyond those achievable with a natural homodimeric (symmetric) Fc molecule, and increased stability and purity of the resulting variant Fc heterodimers. These novel molecules comprise complexes of heterogeneous components designed to alter the natural way antibodies behave and that find use in therapeutics.

Abstract: The present disclosure relates generally to immunoglobulin-related compositions (e.g., antibodies or antigen binding fragments thereof) that can bind to CD3 and uses thereof.

Abstract: Provided are heterodimer pairs comprising a first heterodimer and a second heterodimer wherein each heterodimer comprises an immunoglobulin heavy chain or fragment thereof and an immunoglobulin light chain. At least one of the heterodimers comprises amino acid modifications in the CH1 and/or CL domains, amino acid modifications in the VH and/or VL domains or a combination thereof. The modified amino acid residues are part of the interface between the light chain and heavy chain and are modified in order to create preferential pairing between each heavy chain and a desired light chain such that when the two heavy chains and two light chains of the heterodimer pair are co-expressed in a mammalian cell, the heavy chain of the first heterodimer preferentially pairs with one of the light chains rather than the other. Likewise, the heavy chain of the second heterodimer preferentially pairs with the second light chain rather than first.

Abstract: The provided scaffolds have heavy chains that are asymmetric in the various domains (e.g. CH2 and CH3) to accomplish selectivity between the various Fc receptors involved in modulating effector function, beyond those achievable with a natural homodimeric (symmetric) Fc molecule, and increased stability and purity of the resulting variant Fc heterodimers. These novel molecules comprise complexes of heterogeneous components designed to alter the natural way antibodies behave and that find use in therapeutics.

Abstract: The provided scaffolds have heavy chains that are asymmetric in the various domains (e.g. CH2 and CH3) to accomplish selectivity between the various Fc receptors involved in modulating effector function, beyond those achievable with a natural homodimeric (symmetric) Fc molecule, and increased stability and purity of the resulting variant Fc heterodimers. These novel molecules comprise complexes of heterogeneous components designed to alter the natural way antibodies behave and that find use in therapeutics.

Abstract: The present invention provides a process and methods for producing asymmetric antibodies in a mammalian expression system. The asymmetric antibodies are transiently or stably expressed and in cells that stably express the asymmetric antibody, following a rapid 2-step process of stable pool to clone, a highly pure asymmetric antibody expressing clone can be identified at a success frequency that permits for screening of tens of clones rather than thousands. The asymmetric antibodies are produced at a high titre and with a high level of purity with no contaminating homodimer antibodies following protein A purification with a step yield of near 100%. Typical downstream purification processes employ standard hydrophobic interaction chromatography (HIC) and/or cation exchange (CEX) resins and the antibody is stable within a wide dynamic range of buffer pH (4-8) and within the requirements for manufacturing antibodies for pre-clinical and clinical applications.

Abstract: The provided scaffolds have heavy chains that are asymmetric in the various domains (e.g. CH2 and CH3) to accomplish selectivity between the various Fc receptors involved in modulating effector function, beyond those achievable with a natural homodimeric (symmetric) Fc molecule, and increased stability and purity of the resulting variant Fc heterodimers. These novel molecules comprise complexes of heterogeneous components designed to alter the natural way antibodies behave and that find use in therapeutics.

Abstract: The present invention provides heterodimer pairs that can comprise a first heterodimer and a second heterodimer wherein each heterodimer comprises an immunoglobulin heavy chain or fragment thereof and an immunoglobulin light chain or fragment thereof. At least one of the heterodimers can comprise one or more amino acid modifications in the CH1 and/or CL domains, one or more amino acid modifications in the VH and/or VL domains, or a combination thereof. The modified amino acid(s) can be part of the interface between the light chain and heavy chain and are typically modified to create preferential pairing between each heavy chain and a desired light chain such that when the two heavy chains and two light chains of the heterodimer pair are co-expressed in a cell, the heavy chain of the first heterodimer preferentially pairs with one of the light chains rather than the other. Likewise, the heavy chain of the second heterodimer typically preferentially pairs with the second light chain rather than first.