What Sijian Bio does

Sijian Bio is a clinical-stage biotechnology company founded in 2017 and headquartered in Shanghai's Zhangjiang Hi-Tech Park, focused on developing innovative therapeutics for oncology and autoimmune diseases. The company's core asset is its proprietary EZWi-Fit® ADC linker-payload technology platform, which employs stable-cleavable cysteine linkers conjugated with Topoisomerase I inhibitor payloads (SN38/exatecan). The platform is claimed to deliver superior in vivo antitumor activity, improved safety and pharmacokinetics, activity in MMAE/Dxd-resistant models, and effective bystander killing in heterogeneous tumors, with globally owned intellectual property and freedom-to-operate space.

Sijian Bio's lead pipeline candidate ESG401, a Trop-2 ADC with DAR=8, is in two Phase III registrational trials in China for HR+/HER2- breast cancer and first-line triple-negative breast cancer (TNBC), and received CDE Breakthrough Therapy Designation in November 2024. ESMO 2025 data reported 82.9% ORR and 13.0-month median PFS in 1L mTNBC. The second clinical asset, ESG206, is a First-in-Class glycoengineered anti-BAFF-R monoclonal antibody in Phase I/II development for ITP, Sjögren's syndrome, and SLE, while ESG406 (next-generation ADC) entered Phase I in 2025. Multiple earlier-stage ADC candidates (ESG403, ESG407/DLL3, ESG409/B7-H3, ESG411/412/413 bispecifics, ESG414/416/421) round out the pipeline.

Sijian Bio operates an asset-light, partnership-driven commercialization model. The company has no commercial products; instead it monetizes the EZWi-Fit® platform and select pipeline assets through upfront fees, milestone payments, and tiered royalties on net sales. Notable transactions include a $1.03 billion global licensing of IPN60300/ESG408 to Ipsen (July 2024), an exclusive option agreement with ConjugateBio with potential milestones exceeding $100 million (April 2025), and multiple regional/global platform licenses (Anke Bio, Sidewinder, Innolake, SunRock Biopharma, Sovran Bio, Huahui Health). Cumulative disclosed equity funding is approximately CNY 305 million (~USD 42 million) across Seed, Pre-A, Series A, and Series A+ rounds.

Name

Sijian Bio

Legal name

Shanghai Escugen Biotechnology Co., Ltd. (上海诗健生物科技有限公司)

Website

https://escugen.com.cn

Company type

Private

Founded year

2017

Operating status

Operating

Headcount range

1–10 employees

Short description

Sijian Bio is a Shanghai-based clinical-stage biotechnology company developing oncology and autoimmune therapeutics based on its proprietary EZWi-Fit® ADC linker-payload platform, monetized primarily through global licensing and co-development partnerships.

Ownership category

akta.pro rank

Product category

Antibody-Drug Conjugates (ADC) / Oncology Biologics

NAICS

Research and Development in Biotechnology (except Nanobiotechnology) (541714), Biological Product (except Diagnostic) Manufacturing (325414)

SIC

Biological Products, (No Disgnostic Substances) (2836)

akta.pro primary industry

Antibody-Drug Conjugates (ADCs) & Antibody Conjugates (HLAAAAAE)

akta.pro secondary industries

Protein Engineering & Directed Evolution Platforms (enzyme/therapeutic protein optimization) (HLAAAIAC), Immunology & Inflammation Pharmaceuticals (HLAIAAAD)

Keywords

• Antibody-drug conjugates
• Oncology drug development
• ADC linker-payload platform
• Monoclonal antibody therapeutics
• Autoimmune disease biologics

Headquarters

HQ city

Pudong

HQ country

China

HQ region

Asia

Offices4 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Personnel, Technology or R&D, Operations, Marketing or Sales, Infrastructure

Revenue model

1. Platform Technology Licensing: Sijian Bio licenses its EZWi-Fit® ADC platform technology to domestic and international biotech companies, receiving upfront payments, milestone payments, and tiered royalties on net sales.
2. Co-development and Licensing Deals: Joint development of ADC candidates with partners, followed by out-licensing to global pharmaceutical companies for development and commercialization. Example: FS001/ESG408 licensed to Ipsen for $1.03 billion total deal value.
3. Milestone Payments: Development, regulatory, and commercialization milestone payments from platform licensing and co-development partnerships, such as over $100 million from ConjugateBio and over $1 billion from Ipsen.

Go-to-market motion3 records

Distribution channels3 records

Marketing channels4 records

Core offering

Sijian Bio develops a proprietary next-generation antibody-drug conjugate (ADC) linker-payload technology platform called EZWi-Fit® and uses it to build a clinical-stage pipeline of oncology and autoimmune drug candidates. The company monetizes its platform and pipeline primarily through out-licensing and co-development partnerships with domestic and international biopharmaceutical companies, receiving upfront payments, development and regulatory milestones, and tiered royalties on net sales.

Product overview

Sijian Bio is a clinical-stage biotechnology company headquartered in Shanghai, China (established 2017 in Zhangjiang Hi-Tech Park), focusing on innovative drug development for oncology and autoimmune diseases. The company's proprietary EZWi-Fit® platform is a next-generation ADC linker-payload technology with global IP. The lead product ESG401 (Trop2 ADC) has entered Phase III clinical trials in China for breast cancer and received Breakthrough Therapy Designation for first-line TNBC. ESG206 (BAFF-R mAb) is advancing through clinical trials for B-cell malignancies and autoimmune diseases including ITP and Sjögren's syndrome. The company has successfully out-licensed the EZWi-Fit® platform and multiple ADC candidates (including IPN60300/FS001 to Ipsen) to international partners, and maintains a pipeline of multiple ADC candidates at various clinical and preclinical stages targeting solid tumors including DLL3, B7-H3, and bispecific formats.

Differentiator

Problem solved

Functional benefit

Brands

• EZWi-Fit®: Next-generation ADC linker-payload technology platform with global IP, featuring stable cleavable linkers and Topoisomerase I inhibitor payloads with superior safety, efficacy, anti-drug resistance, and pharmacokinetic properties.
• ESG401
• ESG206
• ESG406

Products and services

• EZWi-Fit® ADC Linker-Payload Platform Next-generation antibody-drug conjugate (ADC) linker-payload technology platform employing stable-cleavable linkers with topoisomerase I inhibitor payloads (SN-38 and exatecan). Globally owned IP with strong freedom-to-operate. Licensed and used internally to generate multiple ADC candidates with superior antitumor activity, anti-drug resistance, and pharmacokinetic properties versus benchmark ADC technologies.
• ESG401 (Trop2 ADC) Best-in-Class Trop2-targeted ADC composed of a humanized Trop-2 antibody conjugated to SN-38 via a stable-cleavable linker (DAR=8). Being developed for HR+/HER2- breast cancer and first-line triple-negative breast cancer (TNBC). Granted CDE Breakthrough Therapy Designation in November 2024 for first-line TNBC and is currently in Phase III clinical trials in China.
• ESG206 (BAFF-R Monoclonal Antibody) First-in-Class glycoengineered (afucosylated) humanized anti-BAFF-R monoclonal antibody that blocks BAFF/BAFF-R signaling and depletes B-cells via enhanced ADCC. Being developed for B-cell malignancies and autoimmune diseases including primary immune thrombocytopenia (ITP), primary Sjogren's syndrome, and systemic lupus erythematosus. Clinical trials ongoing in China and Australia.
• ESG406 Next-generation ADC developed using the EZWi-Fit® platform showing broad-spectrum antitumor activity and significant anti-drug resistance, with demonstrated activity in PDX models unresponsive to other same-target ADCs and in primary/secondary ADC-resistant models. GLP NHP safety studies showed HNSTD of 60 mg/kg. Currently in Phase I clinical trial in China for gastrointestinal tumors, lung cancer, and other solid tumors.
• IPN60300 / FS001 / ESG408 (ITGA2 ADC) First-in-Class ADC targeting ITGA2, co-developed with Foreseen Biotech using Sijian Bio's EZWi-Fit® platform with an exatecan payload. Licensed globally to Ipsen (France) in July 2024 for total transaction value of $1.03 billion including upfront, development milestones, and commercial royalties. Currently in Phase I/II clinical trials (NCT07213817).
• SRB123 (CCR9 ADC) First-in-Class ADC targeting C-C motif chemokine receptor 9 (CCR9), co-developed with SunRock Biopharma by combining SunRock's SRB1 antibody with Sijian Bio's EZWi-Fit® linker-payload platform. Designed for solid tumors with high CCR9 expression including pancreatic, ovarian, and lung cancer.

Quantifiable outcome

• 82.9% ORR in first-line TNBC with 13.0 months median PFS (ESMO 2025 data)
• +3 more outcomes

Named customers3 records

Segments3 records

Ideal customer profiles2 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature4 records

Partnerships

Nine partnerships are on record, tiered major, core, flagship and minor.

• Huahui Health (华辉安健)majorStrategic or Co-development Partner · 8 September 2025Global exclusive co-development agreement for a novel undisclosed tumor target. Combines Sijian Bio's EZWi-Fit® ADC platform with Huahui Health's tumor-specific fully human antibody development capabilities to develop a potential First-in-Class ADC candidate for multiple solid tumor indications.
• SunRock BiopharmamajorStrategic or Co-development Partner · 16 June 2025Strategic alliance to co-develop SRB123, a First-in-Class ADC targeting CCR9 for solid tumors including pancreatic, ovarian, and lung cancer. Combines SunRock's SRB1 antibody with Sijian Bio's EZWi-Fit® platform. Joint patent filed with reciprocal licensing options.
• Sovran Bio, Inc.coreStrategic or Co-development Partner · 12 June 2025Strategic collaboration to leverage Sovran's broad-spectrum disease targeting capabilities with Sijian Bio's EZWi-Fit® platform technology. Jointly advancing multiple novel antibody and ADC therapeutic candidates into clinical trials, with shared development responsibilities and upside.
• ConjugateBiomajorTechnology or Integration · 25 April 2025Exclusive option agreement for EZWi-Fit® platform technology licensing. ConjugateBio, based in Princeton, New Jersey, gains exclusive option to license Sijian Bio's next-generation ADC platform for specific targets. Potential milestone payments exceed $100 million plus tiered royalties on net sales.
• Innola (英诺湖)coreTechnology or Integration · 26 July 2024Global exclusive licensing agreement for Innola to use EZWi-Fit® in their ADC product development. Innola负责全球范围内的临床开发、生产和商业化，向诗健生物支付首付款、里程碑付款和分级特许权使用费。
• Sidewinder Therapeutics, Inc.coreTechnology or Integration · 17 July 2024Global exclusive licensing of EZWi-Fit® platform technology for Sidewinder to develop ADC products targeting specific undisclosed targets.
• Ipsen Pharma SASflagshipOEM/ Whitelabel/ Licensing Partner · 11 July 2024FS001/ESG408 (IPN60300) licensed to Ipsen for global development, manufacturing and commercialization. Total transaction value of $1.03 billion including upfront, development milestones, and commercial royalties. ADC co-developed with Foreseen Biotech using Sijian Bio's EZWi-Fit® platform. Currently in Phase I/II clinical trials (NCT07213817).
• Xing Tai Hao (兴泰濠制药)minorStrategic or Co-development Partner · 13 May 2024Strategic cooperation leveraging Sijian Bio's ADC R&D capabilities and EZWi-Fit® platform advantages combined with Xing Tai Hao's expertise in functional small molecule compounds, high-potency anti-tumor drug manufacturing, cGMP management, and regulatory affairs for domestic and international ADC product development.
• Anke Bio (安科生物)coreTechnology or Integration · 18 April 2024ADC platform technology licensing agreement. Sijian Bio授权安科生物使用EZWi-Fit®平台进行ADC产品开发。安科生物负责大中华地区的临床开发、商业化生产和销售，并向诗健生物支付权益付款及销售提成。诗健生物保留海外权益。

Scale indicators5 records

Recent moves6 records

Expansion highlights6 records

Direct peers

• RemeGen Co., Ltd. China-based clinical-stage biotech with an approved ADC (Disitamab Vedotin) and a pipeline of additional ADCs including Trop-2 candidates; directly comparable to Sijian Bio as a Chinese ADC developer with global licensing ambitions and a focus on oncology biologics.
• Lepu Biopharma: China-based clinical-stage biotech focused on ADC and oncology biologics with multiple ADC candidates in clinical development and global out-licensing deals; closely comparable in scale, business model, and target indications to Sijian Bio's ADC pipeline.
• Mabwell (Shanghai) Bioscience Co., Ltd. China-based biotech developing innovative biologics including ADCs and monoclonal antibodies across oncology and autoimmune indications; comparable pipeline breadth and stage as a Chinese ADC developer targeting similar tumors.
• Foreseen Biotechnology: China-based ADC developer that co-developed ESG408/IPN60300 with Sijian Bio and licensed it to Ipsen; directly comparable as a fellow Chinese biotech leveraging next-generation ADC technology for global out-licensing deals.

Broad incumbents

• CSPC Pharmaceutical Group: Large China-based pharmaceutical group with a growing oncology biologics portfolio including ADC programs; broader than Sijian Bio but competes in the same Chinese oncology ADC development landscape and pursues similar global out-licensing strategies.
• Innovent Biologics: Major Chinese biotech with approved biologics (PD-1, etc.) and a substantial ADC pipeline; competes for the same talent, partners, and global deal flow as Sijian Bio, although with broader modality coverage and commercial infrastructure.
• Daiichi Sankyo: Global ADC leader with Enhertu and Dato-DXd (both TopI-payload ADCs); the closest large-pharma benchmark for EZWi-Fit's mechanism and the most direct competitive threat to ESG401 in TNBC and breast cancer.
• Gilead Sciences (Immunomedics): Owner of Trodelvy (sacituzumab govitecan), the first approved Trop-2 ADC in TNBC; the primary head-to-head competitive incumbent that ESG401 must differentiate against to gain commercial share.
• Pfizer (Seagen): Global ADC leader with multiple approved ADCs (Adcetris, Padcev, Tukysa, Tivdak) and a broad clinical pipeline; relevant incumbent benchmark for ADC platform business models and partnership/royalty structures similar to those Sijian Bio is building.

Emerging players

• Pyxis Oncology: US-based clinical-stage biotech developing next-generation ADCs and antibody-drug conjugates; comparable as an emerging ADC platform player pursuing partnership-driven business models, although smaller and at an earlier stage than Sijian Bio.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat6 records

Key risks6 records

Key highlights7 records

Customer concentration

Compliance1 record

Revenue estimate

Valuation estimate

Number of profiles

Profiles2 records

Funding overview

Funding rounds1 record

Investors3 records

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M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Sijian Bio