Aulos reports Phase 2 imneskibart results showing 9.1-month median PFS in melanoma and 5.8 months in CPI-refractory lung adenocarcinoma.
Written By: Saniya Katakdhond, PharmD
Reviewed By: Pharmacally Editorial Team
Aulos Bioscience reported Phase 2 findings for imneskibart (AU-007) combinations in heavily pretreated patients with checkpoint inhibitor (CPI)-refractory melanoma and non-small cell lung cancer (NSCLC). The findings, presented at the Society for Immunotherapy of Cancer (SITC) 2026 Annual Meeting, showed median progression-free survival (PFS) of 9.1 months with the melanoma triplet regimen and 5.8 months in the NSCLC adenocarcinoma cohort. The results also included objective tumour responses, durable disease control and immune changes consistent with imneskibart’s proposed mechanism of action.
Imneskibart Demonstrates Activity in CPI-Refractory Melanoma
The melanoma cohorts evaluated imneskibart with low-dose subcutaneous aldesleukin, with or without nivolumab, in patients whose disease had progressed following previous doublet checkpoint inhibitor therapy.
The triplet combination of imneskibart, aldesleukin and nivolumab achieved a median PFS of 9.1 months and an objective response rate (ORR) of 28% among 18 response-evaluable patients. Responses included one confirmed complete response (CR) and four partial responses (PRs), with tumour reductions of 81%, 74%, 65% and 40%. Patients had received a mean of 2.7 previous treatment lines. Overall survival (OS) remained immature, with a median follow-up of 5.6 months.
The doublet regimen, comprising imneskibart and low-dose aldesleukin without nivolumab, achieved a median PFS of 6.9 months and an ORR of 29% among 14 response-evaluable patients. The disease control rate (DCR) was 93%, with nine patients achieving stable disease. A confirmed complete response remained in follow-up beyond 32 months. Median OS was 16.1 months at a median follow-up of 18 months. Patients had received a mean of 2.4 previous treatment lines.
For historical context, Aulos highlighted median PFS of 4.2 months with lenvatinib plus pembrolizumab in LEAP-004 and 2.1–3.2 months with nivolumab plus relatlimab in RELATIVITY-020. A 2026 retrospective DeCOG study involving 120 heavily pretreated patients reported median PFS of 3.5 months with anti-PD-1 plus lenvatinib; 98% had previously received ipilimumab plus nivolumab. Although these findings provide relevant clinical context, differences in study design and patient populations prevent direct efficacy comparisons.
Clinical Activity in CPI-Refractory NSCLC
The Phase 2 NSCLC cohort evaluated imneskibart with low-dose subcutaneous aldesleukin and avelumab in patients with advanced disease following previous checkpoint inhibitor therapy.
As of the September 18, 2026 data cutoff, 26 patients with adenocarcinoma or squamous histology were included, of whom 16 had adenocarcinoma. Among 14 response-evaluable adenocarcinoma patients, the triplet regimen achieved a median PFS of 5.8 months, a confirmed ORR of 21% and a DCR of 86%. Three patients achieved confirmed objective responses, while nine experienced stable disease. Patients had received a mean of 2.6 previous treatment lines. Median OS had not been reached at a median follow-up of 10.6 months.
Aulos compared these findings with the 3.6-month median PFS reported with docetaxel in the nonsquamous NSCLC subgroup of the Phase 3 TROPION-Lung01 trial. However, differences in prior treatment exposure and patient characteristics limit cross-trial comparisons.
Imneskibart’s IL-2-Redirecting Mechanism
Imneskibart is an investigational human IgG1 monoclonal antibody designed to selectively bind the CD25-binding region of interleukin-2 (IL-2). Its proposed mechanism involves redirecting IL-2 activity towards immune effector cells while limiting stimulation of regulatory T cells (Tregs).
By preventing IL-2 from binding to CD25-containing trimeric receptors, imneskibart is designed to preserve IL-2 signalling through receptors on effector T cells and natural killer (NK) cells. The approach aims to promote antitumour immune activity while reducing immunosuppressive signalling.
Pharmacodynamic Findings and Safety Profile
Pharmacodynamic analyses demonstrated sustained reductions in Tregs and increases in CD8/Treg ratios across the melanoma cohorts. Patients with Treg reductions exceeding the median reduction of 56% experienced longer time to progression.
In NSCLC, increased CD8/Treg ratios and NK-cell counts were associated with longer PFS. NK-cell counts increased nearly three-fold from baseline, potentially complementing avelumab’s antibody-dependent cellular cytotoxicity activity.
Most drug-related adverse events were Grade 1 or 2. No capillary leak syndrome or treatment-related deaths were observed, and no new toxicity signals were identified across the evaluated combinations.
Further Clinical Development
Enrollment has been completed across the Phase 2 cohorts evaluating imneskibart with low-dose subcutaneous aldesleukin and either nivolumab or avelumab.
The findings provide preliminary evidence of clinical activity in heavily pretreated, CPI-refractory melanoma and NSCLC. The durable complete response in the melanoma doublet cohort and objective responses in adenocarcinoma NSCLC warrant further evaluation.
However, the small response-evaluable populations, non-randomized study design and differences between historical comparator populations limit conclusions about comparative efficacy. Pharmacodynamic associations support the proposed IL-2-redirection mechanism but do not establish that immune changes caused the observed clinical responses.
Randomized clinical evaluation will be necessary to determine whether these findings translate into clinically meaningful benefit and establish imneskibart’s potential role in these treatment settings.
Reference
Aulos Bioscience’s Imneskibart Demonstrates Outstanding Phase 2 Activity in Checkpoint Inhibitor-Refractory Melanoma and Lung Cancer, Comparing Favorably with Historical Treatment Benchmarks, Aulos Bioscience, 06 November 2026
Study of AU-007, A Monoclonal Antibody That Binds to IL-2 and Inhibits IL-2Rα Binding, in Patients with Unresectable Locally Advanced or Metastatic Cancer, ClinicalTrials.gov ID NCT05267626
About the Writer
Saniya Sanjay Katakdhond (Linkedin) is a Doctor of Pharmacy professional with hands-on experience in patient case review, clinical documentation, medical record analysis, and patient care.
Her hospital experience has strengthened her understanding of clinical conditions, treatment approaches, and multidisciplinary healthcare practices.
With ICH-GCP certification and a research-oriented approach, she brings clinical insight and attention to detail to healthcare content development.
As a healthcare writer, Saniya focuses on translating clinical knowledge and patient-care experience into clear, accurate, and evidence-informed medical content.