BB-1701 Drug Asset Due Diligence Report 2026

This BB-1701 Drug Asset Due Diligence Report was built with PatSnap Life Sciences MCP workflows. Drug & Asset MCP establishes identity, ownership and stage; Clinical Trials MCP checks design, endpoints and readouts; Company & Deal Intelligence MCP reconstructs transaction precedent. Explore the MCP servers used in this report.

Decision date: 18 September 2026. Currency fields are presented in US$ millions as returned by the deal dataset. This is a screening memorandum, not legal, medical, patent or investment advice.

Phase 2

Highest phase

Registered trials

Result records

Matched deals

Executive recommendation: CONDITIONAL GO

Decision memo

Advance with milestone-based economics while efficacy durability, safety differentiation, patent scope, and market positioning are validated.

The central underwriting question is whether BB-1701 can convert its Antibody drug conjugate (ADC) profile and HER2 x Tubulin biology into clinically meaningful differentiation while preserving an investable safety, IP and commercial position.

1. Asset identity and development status

Asset	BB-1701 (query alias: BB-1701)
Modality / target	Antibody drug conjugate (ADC); HER2 x Tubulin; HER2 antagonists, Tubulin inhibitors
Highest global status	Phase 2
Originator	Bliss Biopharmaceutical (Hangzhou) Co., Ltd.
Active developers	Eisai, Inc., Bliss Biopharmaceutical (Hangzhou) Co., Ltd.

The MCP disease footprint includes HER2 Positive Solid Tumors, Non-squamous non-small cell lung cancer, HER2 Positive Breast Cancer. The highest-phase flag is a useful orientation point, but the licensing case depends on indication-level evidence and rights, not the global label alone.

2. Clinical program: design and endpoint audit

Registry	Phase	Status	Enrollment	Lead primary endpoint
CTR20243614	Phase 2	Recruiting	110	Primary endpoint not disclosed in English source
CTR20241422	Phase 2	Recruiting	100	Primary endpoint not disclosed in English source
NCT06188559	Phase 2	Completed	56	Primary endpoint not disclosed in English source

The trial set should be diligenced for randomization, comparator relevance, endpoint hierarchy, analysis population, multiplicity, geographic mix and readout timing. For early-stage studies, safety and dose selection can be as decision-critical as response rate.

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3. Clinical readouts: what is known

A phase II study to evaluate the safety and efficacy of BB-1701 in combination with sintilimab in patients with HER2 expression or mutation in locally advanced/metastatic breast cancer or NSCLC.

Phase 2; n=12; evaluation: Positive. Reported fields: DCR = 80.0 % ; DCR = 57.1 %

1296P - A phase II study to evaluate the efficacy and safety of BB-1701 in advanced or metastatic NSCLC patients with HER2 mutation/amplification

Phase 2; n=26; evaluation: Positive. Reported fields: Disease control rate = 91.7 %

Updated safety and antitumor activity of BB-1701 from study 101 in the multiple dose level cohort of patients with locally advanced/metastatic HER2-low expressing breast cancer.

Phase 1; n=40; evaluation: Positive. Reported fields: TRAE = The most common (≥20%) all grade treatment-related adverse events (TRAEs) were peripheral neuropathy, AST increased, ALT increased, anemia, WBC decreased and hypertriglyceridemia. The most common (≥ 5%) grade 3 TRAEs were peripheral neuropathy and peripheral sensory neuropathy. There were no grade 4 or grade 5 events. ; TRAE = The most common (≥20%) all grade treatment-related adverse events (TRAEs) were peripheral neuropathy, AST increased, ALT increased, anemia, WBC decreased and hypertriglyceridemia. The most common (≥ 5%) grade 3 TRAEs were peripheral neuropathy and peripheral sensory neuropathy. There were no grade 4 or grade 5 events.

These fields are structured evidence signals, not a substitute for statistical review. The next diligence pass should reconcile denominators, confidence intervals, follow-up, censoring, dose cohorts and treatment-emergent toxicity against the original abstract, registry and protocol.

4. Market and competitive position

BB-1701 addresses HER2 Positive Solid Tumors, Non-squamous non-small cell lung cancer, HER2 Positive Breast Cancer. Commercial attractiveness rests on addressable patients, treatment-line placement, duration, administration burden, pricing and displacement of entrenched standards. The modality—Antibody drug conjugate (ADC)—must demonstrate a benefit large enough to offset class-specific safety and operational costs.

The MCP screen returned 2 matched transaction record(s) under the scope “asset-specific.” Partner activity is a market-validation signal, but it does not establish net present value.

5. Transaction precedent and economics

Date	Transaction	Phase at deal	Disclosed economics
2025-03-21	Eisai's abandoned Enhertu challenger set to live on at BlissBio	Phase 2	US$2,000.0M stated total
2018-04-09	Morphotek Announces Agreement to License its Proprietary Eribulin-Linker Payload to Bliss Biopharmaceutical Co., Ltd. for Development of a Therapeutic Antibody-Drug Conjugate (ADC)*	Not disclosed	Financial terms not disclosed

Headline values are not directly comparable. Diligence should normalize upfront cash, equity, development and sales milestones, tiered royalties, opt-in mechanics, cost sharing, change-of-control clauses and geography.

6. IP and freedom-to-operate screen

The milestone feed surfaced a patent-application signal described as “Use of an antibody-drug conjugate in inhibiting the growth of non-EGFR-expressing tumors”.

The claim chart should separately test composition or sequence coverage, formulation and dosing, indication and biomarker claims, combinations, manufacturing know-how, prosecution history, term extensions and third-party blocking rights.

7. Principal risks and diligence gates

Clinical differentiation versus current standards and pipeline competitors
Safety, dose optimization, and long-term tolerability
Patent scope, territorial rights, manufacturing, and commercial positioning

Cross-functional diligence should also test CMC comparability, supply chain, pharmacovigilance, regulatory correspondence, data integrity, investigator concentration, partner obligations and change-of-control restrictions.

8. Final go/no-go memorandum

CONDITIONAL GO