Aulos Bioscience, an immuno-oncology company working to revolutionize cancer care through development of its lead immune-activating antibody therapeutic, imneskibart (AU-007), today announced positive Phase 2 data demonstrating clinical activity with imneskibart-based regimens in heavily pretreated patients with doublet checkpoint inhibitor (CPI)-refractory melanoma and CPI-refractory adenocarcinoma non-small cell lung cancer (NSCLC). The findings, presented in two posters at the Society for Immunotherapy of Cancer (SITC) Annual Meeting in Phoenix, Arizona, demonstrate encouraging and durable anti-tumor activity in heavily pretreated patients with limited treatment options, with progression-free survival outcomes that compare favorably with historical benchmarks for available therapies.

The melanoma results demonstrate strong and durable anti-tumor activity with imneskibart plus low-dose, subcutaneous aldesleukin, with and without nivolumab, in patients whose disease had progressed following prior doublet CPI therapy. The triplet regimen of imneskibart plus low-dose, subcutaneous aldesleukin and nivolumab achieved a median progression-free survival (PFS) of 9.1 months and an objective response rate (ORR) of 28% among 18 response-evaluable patients, including one confirmed complete response. The doublet regimen of imneskibart plus low-dose, subcutaneous aldesleukin without nivolumab achieved a median PFS of 6.9 months and ORR of 29%, including a confirmed complete response lasting more than 32 months. These outcomes are particularly encouraging given that patients had progressed despite prior combination checkpoint inhibitor therapy and received a mean of 2.7 prior lines of treatment in the triplet cohort and 2.4 prior lines in the doublet cohort. Published salvage-treatment studies in anti-PD-1-refractory melanoma reported median PFS of 4.2 months with lenvatinib plus pembrolizumab (LEAP-004) and 2.1 to 3.2 months with nivolumab plus relatlimab (RELATIVITY-020), although these studies included different patient populations. A 2026 multicenter retrospective study by the Dermatologic Cooperative Oncology Group (DeCOG) of 120 heavily pretreated patients with advanced melanoma receiving anti-PD-1 plus lenvatinib reported median PFS of 3.5 months; 98% had previously received ipilimumab plus nivolumab. This provides a particularly relevant, though nonrandomized, historical context for the 9.1- and 6.9-month median PFS outcomes reported here.

The NSCLC results provide additional evidence of imneskibart’s activity across difficult-to-treat, CPI-refractory tumors. In heavily pretreated patients with advanced adenocarcinoma NSCLC, the triplet regimen of imneskibart plus low-dose, subcutaneous aldesleukin and avelumab achieved a median PFS of 5.8 months, a confirmed ORR of 21% and a disease control rate (DCR) of 86%. Median overall survival (OS) had not been reached at a median follow-up of 10.6 months. Patients had received a mean of 2.6 prior lines of therapy, making these results particularly encouraging in a heavily pretreated population with limited remaining options. The 5.8-month median PFS compares favorably with the 3.6-month median PFS for docetaxel in the nonsquamous NSCLC subgroup of the randomized Phase 3 TROPION-Lung01 trial. Patients in the overall TROPION-Lung01 docetaxel arm had received an estimated mean of at least 1.5 prior lines of therapy, compared with 2.6 prior lines in the Aulos adenocarcinoma cohort, underscoring the substantial prior treatment exposure in the Aulos study. These cross-trial comparisons are descriptive and do not establish comparative superiority.

“We believe these are exceptional results for imneskibart in two of the most challenging populations in oncology – melanoma and NSCLC patients whose tumors have progressed despite multiple prior treatments,” said Aron Knickerbocker, President and Chief Executive Officer of Aulos Bioscience. “With deep and durable tumor responses, consistent pharmacodynamic activity and manageable safety profiles, these findings provide a compelling foundation for advancing into randomized clinical trials and reinforce our confidence in imneskibart’s differentiated mechanism and its potential to become an important new treatment option in both melanoma and lung cancer.”

As of the September 18, 2026 data cutoff, data were available from 51 melanoma patients in the Phase 1 and Phase 2 cohorts, with and without nivolumab, of whom 14 were evaluable for response in the imneskibart doublet cohort and 18 were evaluable for response in the imneskibart triplet cohort. In NSCLC, data were available from 26 patients (with adenocarcinoma or squamous histology) in the Phase 2 avelumab combination cohort, 16 of adenocarcinoma histology, of whom 14 were evaluable for response. Key findings are summarized below.

Remarkable progression-free survival and durable anti-tumor activity in doublet CPI-refractory melanoma, with ongoing deep tumor reductions observed with imneskibart triplet and doublet regimens

Imneskibart triplet regimen:

  • Median PFS of 9.1 months in patients who received a mean of 2.7 prior lines of therapy.

  • 28% ORR, including one confirmed complete response and four partial responses of -81%, -74%, -65% and -40%.

  • All but four patients had liver and/or lung metastases at baseline, including all patients who achieved a partial response.

  • Median OS data remained immature, with 16 of 20 patients alive or censored at the data cutoff and a median follow-up of 5.6 months.

Imneskibart doublet regimen:

  • Median PFS of 6.9 months in patients who received a mean of 2.4 prior lines of therapy.

  • 29% ORR, with four of 14 patients with the deepest target tumor reductions continuing on treatment for more than one year: -48% (on study for 13 months), -47% (continues on study for 14+ months) and a confirmed complete response (-100%; continues on study, now in follow-up, for 32+ months). One patient with measurable non-target tumors had a -58% reduction in tumor size (on study for 18.5 months).

  • Nine of 14 patients achieved stable disease.

  • Median OS was 16.1 months at a median follow-up of 18 months.

Exceptional progression-free survival exceeding historical chemotherapy benchmarks in CPI-refractory advanced adenocarcinoma NSCLC observed with imneskibart triplet

  • Median PFS of 5.8 months.

  • 21% ORR, with three of 14 patients achieving target tumor reductions of -42% (on study for eight months), -43% (continues on study for 12+ months) and -45% (on study for six months).

  • Nine of 14 patients achieved stable disease, resulting in an 86% disease control rate.

  • Patients had received a mean of 2.6 prior lines of therapy before entering the study.

  • Median OS was not reached at a median follow-up of 10.6 months.

Pharmacodynamic findings continue to support imneskibart’s differentiated mechanism of action

  • In melanoma, treatment produced sustained reductions in regulatory T cells (Tregs) and increases in CD8/Treg ratios. Patients with Treg reductions greater than the median reduction of 56% experienced longer time to progression than patients with smaller reductions.

  • Across the melanoma triplet and doublet regimens, durable increases in CD8 T cells and CD8/Treg ratios were accompanied by corresponding decreases in Tregs, supporting imneskibart’s mechanism of redirecting interleukin-2 (IL-2) toward immune effector cells and away from immunosuppressive Tregs.

  • In NSCLC, CD8/Treg ratios and natural killer (NK) cells increased from baseline substantially, with greater increases associated with longer PFS.

  • The increase in NK cells may complement avelumab’s antibody-dependent cellular cytotoxicity (ADCC) activity. Avelumab is an anti-PD-L1 antibody with an active Fc domain and ADCC effector function mediated by NK cells; on average, imneskibart increased NK cell counts nearly three-fold from baseline.

Imneskibart-based regimens continue to demonstrate manageable safety profiles

  • Most drug-related adverse events were Grade 1 or 2 with imneskibart and low-dose, subcutaneous aldesleukin, alone or in combination with nivolumab or avelumab.

  • No capillary leak syndrome or treatment-related deaths were observed.

  • The emerging safety profile of the doublet and triplet regimens in melanoma and NSCLC is consistent with the known safety profiles of nivolumab and avelumab with imneskibart plus aldesleukin, with no new toxicity signals observed.

Enrollment is complete in all Phase 2 cohorts evaluating nivolumab or avelumab plus imneskibart and low-dose, subcutaneous aldesleukin.

The posters, “Imneskibart, a human monoclonal antibody (mAb), + low-dose subcutaneous IL-2 + avelumab: Phase 2 promising activity in CPI-refractory adenocarcinoma non-small cell lung cancer (NSCLC)” (Abstract 605) and “Imneskibart + low-dose subcutaneous IL-2 ± nivolumab in doublet checkpoint inhibitor-refractory melanoma: promising activity in an ongoing Phase 1/2 study” (Abstract 611) are accessible to meeting registrants as an electronic poster on the SITC Annual Meeting virtual platform. They are also available on the Aulos Bioscience website in the Abstracts and Publications section.

To learn more about the imneskibart clinical trial program, please visit ClinicalTrials.gov (identifier: NCT05267626). For patients and providers in the U.S., please visit www.solidtumorstudy.com. For patients and health professionals in Australia, please visit www.solidtumourstudy.com.

About Imneskibart

Imneskibart (AU-007) is a human IgG1 monoclonal antibody designed by leveraging artificial intelligence that is highly selective to the CD25-binding portion of IL-2. With a mechanism of action unlike any other IL-2 therapeutic in development, imneskibart redirects IL-2 to reinforce anti-tumor immune effects. This is achieved by preventing IL-2, either exogenous or secreted by effector T cells, from binding to trimeric receptors on regulatory T cells while still allowing IL-2 to bind and expand effector T cells and NK cells. This prevents the negative feedback loop caused by other IL-2-based treatments and biases the immune system toward activation over suppression. Imneskibart also prevents IL-2 from binding to CD25-containing receptors on eosinophils, as well as vasculature and pulmonary endothelium, which may significantly reduce the vascular leak syndrome and pulmonary edema associated with high-dose IL-2 therapy.

About Aulos

Aulos Bioscience is an immuno-oncology company working to revolutionize cancer patient care through immune-activating antibody therapeutics that direct patients’ immune systems toward killing tumor cells. Matching world-class machine learning from co-founder Biolojic Design with an in-depth understanding of the immune system, Aulos’ initial clinical candidate, imneskibart (AU-007), is a human antibody designed by leveraging artificial intelligence that harnesses the power of IL-2 to induce tumor killing while limiting the immunosuppression and toxicities typically associated with this validated pathway. The company was founded by Biolojic Design and Apple Tree Partners (ATP) and is led by pioneers in the fields of artificial intelligence, antibody development and cancer immunotherapies. For more information, visit www.aulos.com, X (@AulosBioscience) and LinkedIn.

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