Antibody-based cancer therapy Goydel, Rebecca S; Rader, Christoph
Oncogene,
05/2021, Letnik:
40, Številka:
21
Journal Article
Recenzirano
Odprti dostop
Over the past 25 years, antibody therapeutics have emerged as clinically and commercially successful pharmaceuticals, rapidly approaching 100 Food and Drug Administration approvals with combined ...annual global sales exceeding $100 billion. Nearly half of the marketed antibody therapeutics are used in oncology. These antibody-based cancer therapies can be broken down into three categories based on their different mechanisms of action, i.e., (i) natural properties, (ii) engagement of cytotoxic T cells, and (iii) delivery of cytotoxic payloads. Both natural and engineered properties of the antibody molecule are founded on its highly stable and modular architecture. In this review we provide an overview and outlook of the rapidly evolving landscape of antibody-based cancer therapy.
SARS-CoV-2 variants with spike (S)-protein D614G mutations now predominate globally. We therefore compare the properties of the mutated S protein (S
) with the original (S
). We report here ...pseudoviruses carrying S
enter ACE2-expressing cells more efficiently than those with S
. This increased entry correlates with less S1-domain shedding and higher S-protein incorporation into the virion. Similar results are obtained with virus-like particles produced with SARS-CoV-2 M, N, E, and S proteins. However, D614G does not alter S-protein binding to ACE2 or neutralization sensitivity of pseudoviruses. Thus, D614G may increase infectivity by assembling more functional S protein into the virion.
In this review, we explain why and how rabbit monoclonal antibodies have become outstanding reagents for laboratory research and increasingly for diagnostic and therapeutic applications. Starting ...with the unique ontogeny of rabbit B cells that affords highly distinctive antibody repertoires rich in in vivo pruned binders of high diversity, affinity and specificity, we describe the generation of rabbit monoclonal antibodies by hybridoma technology, phage display and alternative methods, along with an account of successful humanization strategies.
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•Opportunities and challenges of T-biAbs in hematologic and solid malignancies.•Conventional versus in situ delivery of T-biAbs.•T-biAbs versus CAR-Ts in cancer ...immunotherapy.•Employing biAbs to engage the innate immune system.
Among antibody-based cancer therapies, bispecific antibodies (biAbs) have gained momentum in preclinical and clinical investigations following the regulatory approvals of the trailblazing T-cell engaging biAb (T-biAb) blinatumomab. Discussed herein are recent strategies that aim at boosting the potency and mitigating the toxicity of T-biAbs, broadening their therapeutic utility from hematologic to solid malignancies, and generating T-biAbs in situ. In cancer immunotherapy, T-biAbs are facing fierce competition with chimeric antigen receptor T cells (CAR-Ts), a battle for clinical and commercial viability that will be closely watched. However, innovative combinations of T-biAbs and CAR-Ts have also transpired. NK-cell engaging biAbs (NK-biAbs) are reemerging as an alternative that addresses liabilities of T-biAbs. Beyond NK-biAbs, other biAbs designed to recruit cellular and molecular components of the innate immune system will be covered in this reflection on new tools, technologies, and targets.
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The potential of poly (2-oxazoline) or POZ to be a versatile and broad based platform for drug delivery with wide utility in multiple therapeutic areas has long been recognized by ...experts in the field. This feature article provides a case study which describes the chemistry and preclinical studies underlying the Investigational New Drug Application for SER-214, a POZ conjugate of rotigotine, for the treatment of Parkinson’s disease. We report the chemistry, preclinical safety and pharmacology, and the early clinical safety, tolerability and pharmacokinetic data from the Phase I study in patients. SER-214 utilizes a POZ polymer and proprietary custom linker technology to deliver a sustained dose of rotigotine over a period of seven days following a single subcutaneous administration – a result not observed by any other polymer approach that we are aware of. As such, this candidate drug has the promise to be a major advancement in the treatment of Parkinson’s disease. Furthermore, this feature article also highlights the versatility of the POZ polymer platform (POZ™) to deliver cancer drugs by actively targeting cancer cells. Preclinical data reported in this feature showcase the polymer’s attributes in facilitating targeted delivery with folic acid and antibody targeting agents (ADCs). The ability of POZ to reliably delivery large payloads of anticancer drugs is of particular importance when pursuing low-receptor-density targets on the cancer cell. The data presented in this feature, much of it for the first time, establish the broad utility of the POZ polymer platform in drug development. Together with its ease of manufacture, ability to attach drugs to the polymer, and ability to administer an appropriate dose to patients, the results underscore the need to further explore and expand the untapped potential of POZ for the development of new therapeutics for unmet medical needs.
Abstract
Triple-negative breast cancer (TNBC) is a highly diverse group of malignant neoplasms which tend to have poor outcomes, and the development of new targets and strategies to treat these ...cancers is sorely needed. Antibody–drug conjugate (ADC) therapy has been shown to be a promising targeted therapy for treating many cancers, but has only rarely been tried in patients with TNBC. A major reason the efficacy of ADC therapy in the setting of TNBC has not been more fully investigated is the lack of appropriate target molecules. In this work we were able to identify an effective TNBC target for use in immunotherapy. We were guided by our previous observation that in some breast cancer patients the protein tropomyosin receptor kinase B cell surface protein (TrkB) had become immunogenic, suggesting that it was somehow sufficiently chemically different enough (presumably by mutation) to escaped immune tolerance. We postulated that this difference might well offer a means for selective targeting by antibodies. We engineered site-specific ADCs using a dual variable domain (DVD) format which combines anti-TrkB antibody with the h38C2 catalytic antibody. This format enables rapid, one-step, and homogeneous conjugation of β-lactam-derivatized drugs. Following conjugation to β-lactam-derivatized monomethyl auristatin F, the TrkB-targeting DVD-ADCs showed potency against multiple breast cancer cell lines, including TNBC cell lines. In addition, our isolation of antibody that specifically recognized the breast cancer-associated mutant form of TrkB, but not the wild type TrkB, indicates the possibility of further refining the selectivity of anti-TrkB DVD-ADCs, which should enhance their therapeutic index. These results confirmed our supposition that TrkB is a potential target for immunotherapy for TNBC, as well as for other cancers with mutated cell surface proteins.
The interest in replacing the conventional immunoglobulin G (IgG) format of monoclonal antibodies (mAbs) and antibody-drug conjugates (ADCs) with alternative antibody and antibody-like scaffolds ...reflects a need to expand their therapeutic utility and potency while retaining their exquisite specificity, affinity, and low intrinsic toxicity. For example, in the therapy of solid malignancies, the limited tumor tissue penetration and distribution of ADCs in IgG format mitigates a uniform distribution of the cytotoxic payload. Here, we report triple variable domain Fab (TVD-Fab) as a new format that affords the site-specific and stable generation of monovalent ADCs without the Fc domain and a drug-to-antibody ratio (DAR) of 2. TVD-Fabs harbor three variable fragment (Fv) domains: one for tumor targeting and two for the fast, efficient, precise, and stable conjugation of two cargos via uniquely reactive lysine residues. The biochemical and in vitro cytotoxicity properties of a HER2-targeting TVD-Fab before and after conjugation to a tubulin inhibitor were validated. In vivo, the TVD-Fab antibody carrier revealed a circulatory half-life of 13.3 ± 2.5 h and deeper tumor tissue distribution compared to our previously reported dual variable domain (DVD)-IgG1 format. Taken together, the TVD-Fab format merits further investigations as an antibody carrier of site-specific ADCs targeting solid malignancies.
The only current curative treatment for chronic lymphocytic leukemia (CLL) is allogenic hematopoietic stem cell transplantation. Chimeric antigen receptor treatment targeting CD19 for CLL achieved ...some complete responses, suggesting the need for alternative or combinational therapies to achieve a more robust response. In this work, we evaluated CAR-T cells specific for Siglec-6, an antigen expressed in CLL, as a novel CAR-T cell treatment for CLL. We found that detection of SIGLEC6 mRNA and Siglec-6 protein is highly restricted to placenta and immune cells in other tissues and it is not expressed in hematopoietic stem cells. We generated CAR-T cells specific for Siglec-6 based on the sequence of the fully human anti-Siglec-6 antibody (JML1), which was identified in a CLL patient that was cured after allo-hematopoietic stem cell transplantation (alloHSCT), and observed that it specifically targeted CLL cells in vitro and in a xenograft mouse model. Interestingly, a short hinge region increased the activity of CAR-T cells to target cells expressing higher Siglec-6 levels but similarly targeted CLL cells expressing lower Siglec-6 levels in vitro and in vivo. Our results identify a novel CAR-T cell therapy for CLL and establish Siglec-6 as a possible target for immunotherapy.
The Bruton tyrosine kinase inhibitor ibrutinib induces high rates of clinical response in chronic lymphocytic leukemia (CLL). However, there remains a need for adjunct treatments to deepen response ...and to overcome drug resistance. Blinatumomab, a CD19/CD3 bispecific antibody (bsAb) designed in the BiTE (bispecific T-cell engager) format, is approved by the US Food and Drug Administration for the treatment of relapsed or refractory B-cell precursor acute lymphoblastic leukemia. Because of its short half-life of 2.1 hours, blinatumomab requires continuous intravenous dosing for efficacy. We developed a novel CD19/CD3 bsAb in the single-chain Fv-Fc format (CD19/CD3-scFv-Fc) with a half-life of ∼5 days. In in vitro experiments, both CD19/CD3-scFv-Fc and blinatumomab induced >90% killing of CLL cells from treatment-naïve patients. Antileukemic activity was associated with increased autologous CD8 and CD4 T-cell proliferation, activation, and granzyme B expression. In the NOD/SCID/IL2Rγnull patient-derived xenograft mouse model, once-weekly treatment with CD19/CD3-scFv-Fc eliminated >98% of treatment-naïve CLL cells in blood and spleen. By contrast, blinatumomab failed to induce a response, even when administered daily. We next explored the activity of CD19/CD3-scFv-Fc in the context of ibrutinib treatment and ibrutinib resistance. CD19/CD3-scFv-Fc induced more rapid killing of CLL cells from ibrutinib-treated patients than those from treatment-naïve patients. CD19/CD3-scFv-Fc also demonstrated potent activity against CLL cells from patients with acquired ibrutinib-resistance harboring BTK and/or PLCG2 mutations in vitro and in vivo using patient-derived xenograft models. Taken together, these data support investigation of CD19/CD3 bsAb's and other T cell-recruiting bsAb's as immunotherapies for CLL, especially in combination with ibrutinib or as rescue therapy in ibrutinib-resistant disease.
•A CD19/CD3 single-chain Fv-Fc bsAb mediated potent killing of CLL cells by autologous T cells in vitro and in vivo.•bsAb-mediated cytotoxicity was enhanced by prior therapy with ibrutinib and extended to ibrutinib-resistant disease.
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By exploiting a uniquely reactive lysine residue (Lys99) for site-specific attachment of small molecules, the humanized catalytic antibody h38C2 has been used as bioconjugation module in the assembly ...of chemically programmed antibodies and antibody–drug conjugates. Treatment of h38C2 with β-lactam-functionalized small molecules has been previously shown to result in covalent conjugation by selective formation of a stable amide bond with the ε-amino group of the Lys99 residue. Here we report that heteroaryl methylsulfonyl (MS-PODA)-functionalized small molecules represent an alternative bioconjugation strategy through highly efficient, site-specific, and stable arylation of the Lys99 residue. A set of chemically programmed antibodies and antibody–drug conjugates assembled by Lys99 arylation provided proof-of-concept for the therapeutic utility of this alternative bioconjugation strategy. While being equally effective as β-lactam-functionalized ligands for bioconjugation with catalytic antibody h38C2, the MS-PODA moiety offers distinct synthetic advantages, making it highly attractive.