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Review
. 2015 Mar;17(2):339-51.
doi: 10.1208/s12248-014-9710-8. Epub 2015 Jan 22.

Antibody drug conjugates: design and selection of linker, payload and conjugation chemistry

Jessica R McCombs  1 , Shawn C Owen
Affiliations
Review

Antibody drug conjugates: design and selection of linker, payload and conjugation chemistry

Jessica R McCombs et al. AAPS J. 2015 Mar.

Abstract

Antibody drug conjugates (ADCs) have emerged as an important pharmaceutical class of drugs designed to harness the specificity of antibodies with the potency of small molecule therapeutics. The three main components of ADCs are the antibody, the linker, and the payload; the majority of early work focused intensely on improving the functionality of these pieces. Recently, considerable attention has been focused on developing methods to control the site and number of linker/drug conjugated to the antibody, with the aim of producing more homogenous ADCs. In this article, we review popular conjugation methods and highlight recent approaches including "click" conjugation and enzymatic ligation. We discuss current linker technology, contrasting the characteristics of cleavable and non-cleavable linkers, and summarize the essential properties of ADC payload, centering on chemotherapeutics. In addition, we report on the progress in characterizing to determine physicochemical properties and on advances in purifying to obtain homogenous products. Establishing a set of selection and analytical criteria will facilitate the translation of novel ADCs and ensure the production of effective biosimilars.

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Figures

Fig. 1
Fig. 1
Potential isomers from native cysteine conjugation. The locations of conjugation are indicated by stars and intact disulfide bonds are shown as bars. Below the isomer are the chain compositions under denaturing conditions (first line, nonreducing; second line, reducing). For denaturing and nonreducing conditions, the possible species formed are L, H, HL, HH, HHL, and LHHL. For denaturing and reducing, the possible species formed are L0, L1, H0, H1, H2, and H3, in which the numbers indicate how many drug molecules are attached to the light or heavy chain (adapted with permission from Bioconjug. Chem. 16, 1282–90. Copyright 2005 American Chemical Society)
Fig. 2
Fig. 2
A bis-thiol reactive linker was used to cross-link reduced disulfide bonds and simultaneously incorporate a drug. The method required a PEG25 chain due to low solubility of the linker and payload (shown as R 1) (adapted with permission from Bioconjug. Chem. 25, 1124–36. Copyright 2014 American Chemical Society)
Fig. 3
Fig. 3
Site-specific conjugation of alkoxy-amine-derivatized auristatin to anti-Her2 Fab and IgG with pAcPhe. The IgG is coupled by oxime ligation to drug derivitized with a terminal alkoxy-amine through pAcPhe residues (adapted from Proc. Natl. Acad. Sci. U. S. A. 109, 16101–6)
Fig. 4
Fig. 4
Structures of N and C-terminal fusion partners denoting site and sequence of sortase A recognition motifs of each domain (adapted from Levary DA, Parthasarathy R, Boder ET, Ackerman ME (2011) Protein–Protein Fusion Catalyzed by Sortase A. PLoS ONE 6(4): e18342. Copyright 2011 Levary et al.)
Fig. 5
Fig. 5
A glutamic acid side chain found in a conserved amino acid sequence is ligated to a lysine side chain by transglutaminase (adapted with permission from Jeger, S., Zimmermann, K., Blanc, A., Grünberg, J., Honer, M., Hunziker, P., Struthers, H. and Schibli, R. (2010) Angew. Chem. Int. Ed., 49: 9995–9997. Copyright 2010 Wiley Periodicals Inc.)
Fig. 6
Fig. 6
Native sugars in the glycosylated sites of antibodies can be conjugated to functional linkers in a two-step process: a internal mannose or terminal sialic acid residues are reduced to aldehydes and b aldehydes react with linkers containing hydroxylamine or hydrazines to produce oxime and hydrazones, respectively
Fig. 7
Fig. 7
a IgG antibody crystal structure: light chains (red), heavy chains (blue), nucleotide binding site (NBS, boxed). b Rituximab (PDB: 2OSL) with the four NBS residue side chains depicted, two on the light chain and two on the heavy chain; site of conjugation highlighted in purple. c Proposed UV-NBS cross-linking mechanism between the IBA-ligand (R-IBA) and NBS light chain residue Y/F42 (reprinted from Alves, N. J.; Champion, M. M.; Stefanick, J. F.; Handlogten, M. W.; Moustakas, D. T.; Shi, Y.; Shaw, B. F.; Navari, R. M.; Kiziltepe, T.; Bilgicer, B. Biomaterials 2013, 34, 5700–5710, with permission from Elsevier)
Fig. 8
Fig. 8
Linkers provide a functional handle to conjugate drug payloads to the antibody scaffold. One important aspect of linker chemistry is the mechanism of drug release. Representative examples of each type are shown: a nondegradable linkers, b chemically degradable linkers can be cleaved by hydrolysis or reduction, and c enzymatically degradable linkers are first cleaved and may further degrade by inclusion of self-immolative benzyl-alcohol spacers
Fig. 9
Fig. 9
ESI-MS is used to produce these deconvoluted mass spectra of a deglycosylated ADC in red. The ADC mixture of six different species in red is compared to that of the unconjugated mAb in black (reprinted with permission from Anal. Chem. 84, 2843–2849. Copyright 2012 American Chemical Society)
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References

    1. Jaracz S, Chen J, Kuznetsova LV, Ojima L. Recent advances in tumor-targeting anticancer drug conjugates. Bioorg Med Chem. 2005;13(17):5043–5054. doi: 10.1016/j.bmc.2005.04.084. - DOI - PubMed
    1. Lewis Phillips GD, Li G, Dugger DL, Crocker LM, Parsons KL, Mai E, et al. Targeting HER2-positive breast cancer with trastuzumab-DM1, an antibody–cytotoxic drug conjugate. Cancer Res. 2008;68(22):9280–9290. doi: 10.1158/0008-5472.CAN-08-1776. - DOI - PubMed
    1. Senter PD, Sievers EL. The discovery and development of brentuximab vedotin for use in relapsed Hodgkin lymphoma and systemic anaplastic large cell lymphoma. Nat Biotechnol. 2012;30(7):631–637. doi: 10.1038/nbt.2289. - DOI - PubMed
    1. Acchione M, Kwon H, Jochheim CM, Atkins WM. Impact of linker and conjugation chemistry on antigen binding, Fc receptor binding and thermal stability of model antibody-drug conjugates. MAbs. 2012;4(3):362–372. doi: 10.4161/mabs.19449. - DOI - PMC - PubMed
    1. Boylan NJ, Zhou W, Proos RJ, Tolbert TJ, Wolfe JL, Laurence JS. Conjugation site heterogeneity causes variable electrostatic properties in Fc conjugates. Bioconjug Chem. 2013;24(6):1008–1016. doi: 10.1021/bc4000564. - DOI - PMC - PubMed

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