Missoula – November 06, 2026 -- Inimmune's TLR7/8 agonist INI-4001 produced no dose-limiting toxicities in a 10-patient Phase 1 study of heavily pretreated advanced solid tumor patients, and the company is weighing a Phase 2a start as early as 2027, subject to funding or partnership support.
INI-4001 tolerated up to 7.2 μg/kg across five dose levels
The trial (NCT06302426) tested the investigational small molecule for safety, tolerability, pharmacokinetics, pharmacodynamics and preliminary antitumor activity. Patients received INI-4001 intravenously once weekly across five escalating dose levels. Adverse events were primarily transient, consistent with innate immune activation, and generally resolved within 24 hours. No concerning pharmacokinetic findings were reported.
Cytokine spikes at the proposed Phase 2 dose confirm target engagement
At the proposed Phase 2 dose, maximum increases from pre-dose levels reached 13.5-fold for IFNγ and 4.15-fold for IP-10. Circulating lymphocytes fell in a transient, dose-dependent manner and rebounded within 24 hours. Inimmune said this pattern is consistent with potential lymphocyte trafficking to tissues and tumors.
Two of 10 patients remain on treatment without progression
The study was not designed to evaluate efficacy. Even so, two patients continue to receive INI-4001 under compassionate use with no reported disease progression. One patient with a small bowel neuroendocrine tumor has been treated for 19 months. A second, with chondrosarcoma, has been treated for nine months.
Inimmune targets monotherapy and combination development
CEO David Burkhart, Ph.D., said "many patients do not respond to existing therapies" and that INI-4001 may make tumors more responsive to immunotherapy. He said the data support continued development as a monotherapy, while the company also looks to explore combinations with other cancer treatments.
Shannon Miller, Ph.D., Vice President at Inimmune, presented the data in a late-breaking poster at the Society for Immunotherapy of Cancer (SITC) Annual Meeting. The abstract is published in the Journal for ImmunoTherapy of Cancer. Inimmune is privately held, and the Phase 2a plan depends on securing external funding or a partner.