Ajinomoto and Exelixis have signed a license agreement with to incorporate AJICAP®, Ajinomoto’s proprietary site-specific bioconjugation and linker technologies, in the development of novel antibody-drug conjugate (ADC) programs being developed by Exelixis.
Exelixis, a commercially successful, oncology-focused biotechnology company, strives to accelerate the discovery, development and commercialization of new medicines for difficult-to-treat cancers.
Using its network of biotherapeutics collaborations, the Exelixis is developing various next generation ADCs. The agreement with Ajinomoto, a technology provider for biopharmaceuticals and the owner of CDMO Ajinomoto Bio-Pharma Services, is one in a series of agreements.
In November 2022 the company also signed a license agreement with Catalent’s Redwood Bioscience subsidiary. Under the terms of this agreement, Exelixis obtained an exclusive license to three target programs with lead antibody and/or ADC candidates. These ADC candidates were developed using Catalent’s proprietary SMARTag® technology, and each of the licensed antibodies has potential for development as an ADC or other biologic therapy using a variety of technologies to which Exelixis has access through its partner network.
In September 2020, Exelixis and Catalent entered into a separate agreement under which Catalent is applying its SMARTag bioconjugation platform to build ADCs using monoclonal antibodies from Exelixis’ growing preclinical pipeline.
Developed by Catalent’s Redwood Bioscience subsidiary, the SMARTag® technology platform provides optimized site-specific protein-modification and linker technologies for ADCs and other bioconjugates. The SMARTag® platform overcomes the limitations associated with traditional protein chemistries that produce heterogeneous products with variable conjugate potency, toxicity, and stability and enables the development of ADCs with a wider therapeutic window and improved manufacturability.
The SMARTag technology platform was developed by Redwood Bioscience based on discoveries in the lab of Carolyn R. Bertozzi, Ph.D., winner of the 2022 Nobel Prize in Chemistry.
Ajinomoto’s Site-specific technology
Traditionally, antibody-drug conjugates possess a stochastic distribution of cytotoxic payloads linked to several different amino acid residues of an antibody. This heterogeneous nature of stochastic ADCs results in a relatively complex conjugation-site characterization. To improve upon this traditional ADC technology, researchers at Ajinomoto developed a chemical conjugation platform for site-specific modification of native antibodies using a class of IgG Fc-affinity reagents, called AJICAP®. 
This proprietary site-specific bioconjugation and stable linker technology is compatible with commonly used antibody isotypes, and enables the synthesis of ADCs from native IgG antibodies.
The technology includes an “off-the-shelf” feature, allowing any therapeutic antibody at any stage of development to be conjugated to drug-payloads of choice without the need for antibody engineering or cell line development, and stable/hydrophilic linkers to generate antibody-drug conjugates with an enhanced therapeutic window.
As part of the license agreement with Ajinomoto, Exelixis will have the right to use the AJICAP technology to support its aim of advancing multiple ADCs with the potential for higher efficacy and lower toxicity than currently available options. Under the terms of the agreement, Ajinomoto is eligible to receive development, regulatory and commercial milestone payments as well as royalties on commercial sales.
“We are very excited to support Exelixis, a leader in oncology drug discovery, development, and commercialization, in the development of novel antibody-drug conjugates,” said Tatsuya Okuzumi, Ph.D, General Manager, Business Development Group, Bio-Pharma Services Department, Ajinomoto.
“The combination of Exelixis’ antibodies and payloads with Ajinomoto’s AJICAP opens up a wide range of oncology applications and may be harnessed to provide a clinical benefit to patients,” Okuzumi concluded.
 Matsuda Y, Malinao MC, Robles V, Song J, Yamada K, Mendelsohn BA. Proof of site-specificity of antibody-drug conjugates produced by chemical conjugation technology: AJICAP first generation. J Chromatogr B Analyt Technol Biomed Life Sci. 2020 Mar 1;1140:121981. doi: 10.1016/j.jchromb.2020.121981. Epub 2020 Jan 27. PMID: 32036254.
 Matsuda Y. Recent advances in antibody-drug conjugates produced using chemical conjugation technology – J. ADC. January 5, 2023. DOI: 10.14229/jadc.2023.01.05.002.
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