"Peptide-payload conjugate (7) was prepared by reacting 2mM aizoacetyl-Ser-Lys-Gly-Ser-Lys (CPC scientific, inc. Sunnywale, CA) with 8 mM NHS-ester payload [19] in 50% Dimethyl sulfoxide (DMSO), 50 mM borate buffer pH 8.5 for 2 h at 37°C."
Abstract
Antibody drug conjugates (ADCs) are no longer an unknown entity in the field of cancer therapy with the success of marketed ADCs like ADCETRIS and KADCYLA and numerous others advancing through clinical trials. The pursuit of novel cytotoxic payloads beyond the mictotubule inhibitors and DNA damaging agents has led us to the recent discovery of an mRNA splicing inhibitor, thailanstatin, as a potent ADC payload. In our previous work, we observed that the potency of this payload was uniquely tied to the method of conjugation, with lysine conjugates showing much superior potency as compared to cysteine conjugates. However, the ADC field is rapidly shifting towards site-specific ADCs due to their advantages in manufacturability, characterization and safety. In this work we report the identification of a highly efficacious site-specific thailanstatin ADC. The site of conjugation played a critical role on both the in vitro and in vivo potency of these ADCs. During the course of this study, we developed a novel methodology of loading a single site with multiple payloads using an in situ generated multi-drug carrying peptidic linker that allowed us to rapidly screen for optimal conjugation sites. Using this methodology, we were able to identify a double-cysteine mutant ADC delivering four-loaded thailanstatin that was very efficacious in a gastric cancer xenograft model at 3mg/kg and was also shown to be efficacious against T-DM1 resistant and MDR1 overexpressing tumor cell lines.
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Diao, J., Komura, R., Sano, T., Pantua, H., Storek, K.M., Inaba, H., Ogawa, H., Noland, C.L., Peng, Y., Gloor, S.L. and Yan, D. bioRxiv (2020): 2020-10.
- Departments of Infectious Diseases, Structural Biology, Biochemical and Cellular Pharmacology, Translational Immunology, Pathology, and Early Discovery Biochemistry, Genentech, South San Francisco, CA 94080 USA
The standard assay consists of 6 μL reaction mixture with 3 nM Lgt-DDM, 50 μM phosphatidylglycerol (1,2-dipalmitoyl-sn-glycero-3-phospho-(1’-rac-glycerol), Avanti), 12.5 μM Pal-IAAC peptide substrate derived from the Pal lipoprotein (MQLNKVLKGLMIALPVMAIAACSSNKN, synthesized by CPC Scientific)
Pantua, H., Skippington, E., Braun, M.G., Noland, C.L., Diao, J., Peng, Y., Gloor, S.L., Yan, D., Kang, J., Katakam, A.K. and Reeder, J. MBio 11, no. 5 (2020): 10-1128.
- Departments of Infectious Diseases, OMNI Bioinformatics, Chemistry, Structural Biology, Biochemical and Cellular Pharmacology, Translational Immunology, Pathology, Molecular Biology, Genentech, South San Francisco, California, USA
MQLNKV-L(U13C6,15N)-KGL(U13C6,15N)MIALPVMAIAA-dipalmitoyl2C-SSNKNGG-K-biotin, which upon cleavage by LspA, yields the product peptide dipalmitoyl2C-SSNKNGG-K-biotin. A product standard [dipalmitoyl2C-SSNKNAAK-(NHCH2CH2NH)-biotin; CPC Scientific] was in the reaction mixture as an internal standard for normalization of product quantitation.
Protein-protein and protein-peptide interactions play critical roles in all types of cellular processing. Peptides are natural partners to proteins and, as ligands, bind to proteins with high affinity due to their capacity to adapt to the often flexible protein surface. Despite this, peptides have drawbacks as drug candidates that include low plasma bioavailability, instability from proteolytic enzymes, and poor passive membrane permeability. Some success has been achieved with linear peptides, particularly peptides that maintain α-helical secondary structures. These motifs can be introduced to stabilized α-helical motifs by common “peptide-stapling” approaches, but stapled peptides can suffer from low bioactivity and poor solubility. Another strategy to maintain peptide secondary structure is modification by macrocyclization.
SAN JOSE, CA., Sept 3, 2020 /CPCNewswire/ — CPC Scientific Inc. is pleased to announce that the European Commission (EC) has granted the Conditional Marketing Authorization (CMA) for MYR Pharmaceuticals lead compound HEPCLUDEX®. CPC Scientific serves as a supplier and partner to MYR Pharmaceuticals for the development and manufacturing of bulevirtide (Hepcludex). This drug is […]
Curreli, Francesca, Sofia MB Victor, Shahad Ahmed, Aleksandra Drelich, Xiaohe Tong, Chien-Te K. Tseng, Christopher D. Hillyer, and Asim K. Debnath. Mbio 11, no. 6 (2020): e02451-20.
We have synthesized (CPC Scientific, Inc.) four stapled peptides, as depicted in Figure 2. We also synthesized the linear peptide, NYBSP-C, as a control. Besides, we purchased a linear peptide, SBP1, to use as a control, which was reported recently to bind to SARS-CoV-2 RBD with high affinity (KD = 47nM).
Abdulganiyyu, I. A.; Kaczmarek, K.; Zabrocki, J.; Nachman, R. J.; Marchal, E.; Schellens, S.; Verlinden, H.; Broeck, J. V.; Marco, H.; Jackson, G. E. Insect Biochemistry and Molecular Biology 2020, 103362.
A head-to-tail cyclic, octapeptide analog of Locmi-AKH-I, cycloAKH (cyclo[LNFTPNWG]) was synthesized to severely restrict the conformational freedom of the AKH structure.
Clairfeuille, T., Buchholz, K.R., Li, Q., Verschueren, E., Liu, P., Sangaraju, D., Park, S., Noland, C.L., Storek, K.M., Nickerson, N.N. and Martin, L. Nature 584, no. 7821 (2020): 479-483.
- Departments of Structural Biology, Infectious Diseases, Microchemistry, Proteomics & Lipidomics, Drug Metabolism & Pharmacokinetics, Translational Immunology, BioMolecular Resources, Biochemical & Cellular Pharmacology, Bioinformatics & Computational Biology, Discovery Chemistry Departments, Genentech Inc., South San Francisco, CA, USA.
LAB peptides ([..], CPC Scientific, [..] l, standard solid-phase peptide synthesis) at 10 mM in 50 mM Tris, pH 8, and 100 mM NaCl were diluted in MHB II cation adjusted broth (800 μM top concentration) or LB. Where indicated, EDTA was added to a final concentration of 0.5 mM.
Chan, Leslie W., Melodi N. Anahtar, Ta-Hsuan Ong, Kelsey E. Hern, Roderick R. Kunz, and Sangeeta N. Bhatia. Nature Nanotechnology (2020): 1-9.
HFA-modifed peptides were synthesized by CPC Scientifc (>95% purity). Briefy, the peptide substrate, Ac-CKKK(Cy5)-PEG4-Nle(O-Bzl)-Met(O)2-Oic-Abu-OH, was synthesized on Fmoc-Abu-CTC resin via standard Fmoc solid phase peptide synthesis.