Aspects of the disclosure relate to complexes comprising a muscle-targeting agent covalently linked to a molecular payload. In some embodiments, the muscle-targeting agent specifically binds to an internalizing cell surface receptor on muscle cells. In some embodiments, the molecular payload promotes the expression or activity of a functional dystrophin protein. In some embodiments, the molecular payload is an oligonucleotide, such as an antisense oligonucleotide, e.g., an oligonucleotide that causes exon skipping in a mRNA expressed from a mutant DMD allele.

The invention provides, inter alia, methods of treating a disorder characterized by pathological activity of CD30+ cells, such as in certain solid, hematological and lymphoid cancers, in a non-adult human subject by administering an effective amount of an anti-CD30 ADC (antibody drug conjugate), such as, brentuximab vedotin, to the subject. The invention also provides corresponding kits and articles of manufacture suitable for performing the methods provided by the invention.

Antibodies that include a sulfatase motif-containing tag in a constant region of an immunoglobulin (Ig) heavy chain polypeptide are disclosed. The sulfatase motif can be converted by a formylglycine-generating enzyme (FGE) to produce a formylglycine (fGly)-modified Ig heavy chain polypeptide. An fGly-modified Ig heavy chain polypeptide of the antibody can be covalently and site-specifically bound to a moiety of interest to provide an antibody conjugate. The disclosure also encompasses methods of production of such tagged Ig heavy chain polypeptides, fGly-modified Ig heavy chain polypeptides, and antibody conjugates, as well as methods of use of same.

A first aspect of the invention relates to novel compounds and more precisely to novel bifunctional prodrugs and drugs. An additional aspect of the invention relates to antibody compound conjugates, wherein the compound is a claimed compound, and to pharmaceutical compositions containing the compound or antibody compound conjugate. The invention lastly relates to the use of this compound or antibody compound conjugates according to the invention in order to treat tumour diseases, particularly in mammals.

The present invention relates to linkers having a group of propioloyl, substituted acryl (acryloyl), or disubstituted propanoyl, and using such linkers for the conjugation of compounds, in particular, cytotoxic agents to a cell-binding molecule.

Aspects of the disclosure relate to methods and compositions useful for in vivo and/or in vitro enzyme profiling. In some embodiments, the disclosure provides methods of in vivo enzymatic processing of exogenous molecules followed by detection of signature molecules as representative of the presence of active enzymes associated with diseases or conditions. In some embodiments, the disclosure provides compositions and in vitro methods for localization of enzymatic activity in a tissue sample.

Provided are compositions and methods for reducing off-target toxicity of antibody-drug conjugates (ADCs). The compositions comprise an ADC, and an agent targeted to the drug (payload) that is delivered by or derived from the ADC. The ADC and the agent targeted to the payload may be delivered together or separately in the treatment of various conditions (such as tumors) by ADCs. Examples of agents targeted to payload include antibodies, fragments, or modifications thereof.

Provided is a method of producing an antibody-drug conjugate represented by Formula I

##STR00001## in the formula, Ab is an antibody or an antigen-binding fragment thereof, D is eribulin, m is an integer of 1 to 10, and p is an integer of 1 to 8, the method comprising: a step 1 of obtaining a compound represented by Formula (B) by reaction of eribulin or a salt thereof with a compound represented by Formula (A),

##STR00002## in the formula, m is an integer of 1 to 10 and X is a phenoxy group or a nitrophenoxy group, and

##STR00003## in the formula, n is an integer of 1 to 10, and a step 2 of obtaining the antibody-drug conjugate represented by Formula (I) by reaction of the compound represented by Formula (B) with Ab.

Provided herein are antibody-cytotoxin antibody-drug conjugates and related compounds, such as linker-cytotoxin conjugates and the linkers used to make them, and intermediates in their synthesis; compositions; and methods, including methods of treating cancers

The present invention relates to linkers having a group of propiolyl, substituted acryl (acryloyl), or disubstituted propanoyl, and using such linkers for the conjugation of compounds, in particular, cytotoxic agents to a cell-binding molecule.