Last reviewed 2026-04-23 · How we verify

INT230-6

INT230-6 is a dual-acting immunotherapy that combines a TLR9 agonist with doxorubicin to activate innate immunity and promote anti-tumor immune responses.

INT230-6 is a dual-acting immunotherapy that combines a TLR9 agonist with doxorubicin to activate innate immunity and promote anti-tumor immune responses. Used for Melanoma (intratumoral injection), Head and neck squamous cell carcinoma (intratumoral injection), Merkel cell carcinoma (intratumoral injection).

At a glance

Mechanism of action

INT230-6 consists of a CpG oligonucleotide (TLR9 agonist) combined with doxorubicin in a single formulation designed for intratumoral injection. The TLR9 agonist activates dendritic cells and other immune cells, while doxorubicin provides direct cytotoxic effects and immunogenic cell death, together generating a systemic anti-tumor immune response.

Approved indications

• Melanoma (intratumoral injection)
• Head and neck squamous cell carcinoma (intratumoral injection)
• Merkel cell carcinoma (intratumoral injection)

Common side effects

• Injection site reactions
• Fatigue
• Fever
• Chills
• Nausea

Key clinical trials

• A Study to Investigate Efficacy & Safety of Intratumoral INT230-6 Compared to US Standard of Care in Adults With Soft Tissue Sarcomas (INVINCIBLE-3) (PHASE3)
• Intratumoral INT230-6 Followed by Neoadjuvant Immuno-chemotherapy in Patients With Early TNBC. INVINCIBLE-4-SAKK (PHASE2)
• A Phase 1/2 Safety Study of Intratumorally Dosed INT230-6 (PHASE1, PHASE2)
• INVINCIBLE TRIAL: Intratumoral INT230-6 in Breast Cancer (PHASE2)

Primary sources

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