What changed, and when

Surv BioPharma announced a second close of its Series B, raising an additional ¥670 million on 23 Dec 2025, and listed the new investors by name in a press release PDF, bringing the Series B total to ¥2.17 billion. (Company PDF, 23 Dec 2025) Independent reports carried the same second-close headline and timing. (The Bridge, EN, KEPPLE, JP). The first close of ¥1.5 billion was disclosed on 11 Nov 2025. (PR TIMES company release, 11 Nov 2025). The firm’s official English site uses “Surv BioPharma,” while some media write “Serve Biopharma.” We privilege the company’s spelling. (Company site, The Bridge, EN)

60-second thesis frame

This financing, plus an AMED award of up to ¥2.7 billion decided on 4 Dec 2025, gives Surv runway to prosecute a pivotal program for Surv.m-CRA-1 in primary malignant bone tumors and push its immunogene-armed Surv.m-CRA-2-IC toward first-in-human in 2027. (Company PDF, 23 Dec 2025, AMED award list, 4 Dec 2025) The platform hinges on a survivin-responsive promoter to drive oncolytic adenovirus replication selectively in cancer cells, a mechanism supported by prior publications and the firm’s pipeline page. (Company pipeline, BMC Cancer 2019) Japan-focused licensing with Nippon Zoki suggests a commercialization path if Phase 3 is successful, but pivotal design, manufacturing scalability, and payer acceptance for a rare sarcoma indication remain the gating risks. (Nippon Zoki–Surv license PDF, 5 Aug 2025)

The seven diligence questions

Clinical

• What is the precise Phase 3 design for Surv.m-CRA-1 in primary malignant bone tumors, including control, primary endpoint, and statistical powering, and how do these map to Phase 2 signal and SOC outcomes in Japan and ex-Japan? (Company PDF, 23 Dec 2025)
• How reproducible are Surv.m-CRA-1 responses across histologies and sites, and what is the neutralizing-antibody profile upon repeat dosing for an adenoviral OV? (UMINO/UMIN Phase 1 entry)

Payer or Access

• If Surv.m-CRA-1 secures approval, how will Japan’s NHI price and pay for an OV in a rare bone sarcoma, and will hospital admin fees and handling codes support adoption? (Regulatory path and price formation inferred, verify against PMDA/MHLW precedents)
• Outside Japan, does the Nippon Zoki deal constrain ex-Japan options or create a regional reference that helps or hurts EU, US pricing later? (Nippon Zoki–Surv license PDF, 5 Aug 2025)

Ops or Adoption

• Can Surv scale GMP adenoviral manufacturing, release testing, and cold-chain distribution for hospital use, including vial sizes, stability dating, and BSL handling? (Company PDF, 23 Dec 2025)

Competitive

• Against approved or near-term OVs and sarcoma modalities, where does survivin-promoter targeting show differentiated efficacy or safety, and what are the head-to-head or indirect comparator plans? (BMC Cancer 2019)

Team or Cap table

• Does the investor mix from the second close, including Kyoto University Innovation Capital and Toho Holdings, translate into R&D, clinical network, or go-to-market advantages beyond capital? (Company PDF, 23 Dec 2025, KEPPLE, JP)

Red flags

• Pivotal execution risk, the company cites “extremely favorable” earlier results and a Phase 3 path, but detailed Phase 3 protocol, endpoints, and regulators’ feedback are not yet public. (Company PDF, 23 Dec 2025)
• Manufacturing and repeat-dose immunogenicity risks for adenoviral OVs could limit durability or retreatment, impacting commercial utility. (UMINO/UMIN Phase 1 entry)
• Funding composition, near-term plans rely partly on non-dilutive AMED support up to ¥2.7 billion, exposing timelines to grant administration and milestones. (AMED award list, 4 Dec 2025, Company AMED notice)

Next catalyst

Formal publication or registry of the Surv.m-CRA-1 Phase 3 protocol and site initiations in Japan in 2026, and AMED project kickoff documents for Surv.m-CRA-2-IC, which was selected on 4 Dec 2025. (AMED award list, 4 Dec 2025, Nippon Zoki–Surv license PDF, 5 Aug 2025)

FAQ

• What exactly changed by Surv BioPharma’s “Series B second close of ¥670 million” news on 23 Dec 2025, and why does it matter for the OV program?
  The company disclosed an additional ¥670 million raised in a second close, bringing Series B to ¥2.17 billion and naming six new investors, which supports Phase 3 for Surv.m-CRA-1 and pre-clinical acceleration for 2-IC. (Company PDF, 23 Dec 2025, The Bridge, EN)
• What exactly is Surv BioPharma’s core technology, and how does it differ from approved oncolytic viruses like Imlygic?
  Surv uses a survivin-responsive oncolytic adenovirus (Surv.m-CRA) that replicates only in cells overexpressing survivin, a protein found in nearly all solid tumors but rare in normal tissue (Company technology). This contrasts with Imlygic, which relies on deletion mutations (ICP34.5) for selectivity, potentially offering a more potent replication profile while maintaining safety.
• Which endpoints in prior trials informed the move cited in Surv BioPharma’s Series B second close of ¥670 million on 23 Dec 2025, and how meaningful was the effect size?
  Earlier studies established safety and preliminary activity for survivin-responsive, conditionally replicating adenoviruses, but specific Phase 2 sarcoma endpoints and effect sizes are not fully public in 2025 disclosures, raising a diligence need to review investigator-initiated data. (UMINO/UMIN Phase 1 entry, BMC Cancer 2019)
• What safety issues matter post–Surv BioPharma’s Series B second close of ¥670 million news on 23 Dec 2025, and do they change real-world use?
  Adenoviral OVs raise questions around pre-existing immunity, neutralizing antibodies upon re-dosing, and hospital handling, which will shape labeling and logistics if approved. (Background from clinical registry and literature, UMINO/UMIN Phase 1 entry, BMC Cancer 2019)
• What is the significance of the partnership with Nippon Zoki Pharmaceutical?
  Signed in August 2025, this deal likely offloads the commercialization burden in Japan for the lead asset, allowing Surv to focus on R&D and platform expansion (PR Times). It validates the asset’s commercial potential but may cap Surv’s revenue share in its home market.
• Why is Surv BioPharma’s AMED grant so large relative to the equity raise?
  The ¥2.7 billion grant is part of Japan’s “Drug Discovery Venture Ecosystem Strengthening Project,” which matches VC investment to de-risk high-cost clinical stages for startups (AMED program details). This non-dilutive funding effectively doubles the company’s capital efficiency, a critical advantage in the current funding climate.

Publisher / Disclosure

Publisher, LucidQuest Ventures Ltd. Produced, 26 Dec 2025, 15:44 London. Purpose, general and impersonal information. Not investment research or advice, no offer or solicitation, no suitability assessment. UK, directed at investment professionals under Article 19(5) and certain high-net-worth entities under Article 49(2)(a)–(d) of the Financial Promotion Order 2005. Others should not act on this. Sources and accuracy, public sources believed reliable, provided “as is,” may change without notice. No duty to update. Past performance is not reliable. Forward-looking statements carry risks. Methodology, questions-first framework using public sources. No conflicts. Authors do not hold positions unless stated. © 2025 LucidQuest Ventures Ltd.

Entities / Keywords

Surv BioPharma; Serve Biopharma; Surv.m-CRA-1; Surv.m-CRA-2-IC; survivin promoter; oncolytic adenovirus; primary malignant bone tumor; sarcoma; adenoviral vector; Nippon Zoki Pharmaceutical; Kyoto University Innovation Capital; Toho Holdings; FFG Venture Business Partners; Oita Venture Capital; Sagin Capital & Consulting; Fukuoka Jisho; AMED; PMDA; MHLW; NHI pricing; Japan; Kagoshima University; physician-initiated trial; Phase 3; first-in-human 2027; UMIN; jRCT; CMC; GMP manufacturing.