Phase 1 and preliminary Phase 2 data for AU-007 with low-dose aldesleukin show clinical activity, durable Treg reduction and correlated progression-free survival

Melanoma and non-small cell lung cancer prioritized for further Phase 2 clinical investigation

LARKSPUR, Calif.: Aulos Bioscience, an immuno-oncology company working to revolutionize cancer care through development of potentially best-in-class IL-2 therapeutics, today shared positive results from its Phase 1/2 dose escalation and cohort expansion study of AU-007. The data will be presented in a poster session at the Society for Immunotherapy of Cancer (SITC) 39th Annual Meeting in Houston, Texas.

Preliminary Phase 2 data reveal that a combination of AU-007 and low-dose, subcutaneous aldesleukin is clinically active in melanoma, a finding consistent with Phase 1 data demonstrating clinical activity in a range of patients whose tumors had progressed through prior checkpoint inhibitors. Data from all 77 patients show durable reductions in immunosuppressive Treg cells – a result unprecedented in the IL-2 class – with a correlation between longer progression-free survival outcomes as Treg reduction deepens.

“We believe these data represent preliminary clinical proof of concept for our unique monoclonal antibody, AU-007, and we are confident in its emerging profile as a potential best-in-class therapeutic,” said Aron Knickerbocker, Aulos Bioscience’s president and chief executive officer. “We look forward to presenting a fuller and more mature set of Phase 2 data for melanoma, renal cell carcinoma and non-small cell lung cancer in the first half of next year.”

Key findings from preliminary results of the Phase 1/2 dose escalation and cohort expansion study of AU-007, with data available on 77 patients as of the data cutoff date of September 28, 2024, are as follows:

A tolerable and manageable safety profile was observed at all doses evaluated in Phase 1 dose escalation.

• No dose-limiting toxicity occurred throughout Phase 1 dose escalation.
• Most drug-related adverse events were Grade 1 or 2 except for:
  • Grade 3 anemia in one patient who entered the study with Grade 2 anemia, had rapid disease progression and received only two doses of the study drug.
  • Grade 4 cytokine release syndrome (CRS) in one patient that resolved with steroids, IV fluids and brief vascular pressor support, and did not require tocilizumab. This patient was noted retrospectively to have subclinical elevated IL-6 (5x upper limit of normal) serum levels, likely due to an active case of gout at baseline.
  • Transient Grade 3 elevated lipase in one patient that was not associated with clinical symptoms and resolved without intervention.
  • Transient (3-7 days) Grade 3 or 4 lymphopenias in six patients. The lymphopenias were not associated with adverse outcomes. Transient lymphopenia is a known effect of IL-2 treatment as lymphocytes traffic out of blood and into tissue.

Strong evidence of anti-tumor activity was observed in heavily pre-treated patients, particularly in melanoma.

• Two patients with melanoma refractory to prior anti-CTLA-4 and anti-PD-1 therapy were treated with AU-007 every two weeks (Q2W) and one administration of low-dose, subcutaneous aldesleukin (recombinant human IL-2), and experienced deep and durable tumor shrinkages of 48% and 100% in target lesions.
• One patient in dose escalation with acral melanoma that progressed rapidly on prior anti-PD-1 therapy received AU-007 Q2W and one loading dose of subcutaneous aldesleukin. This patient remained on AU-007 therapy for 11 months with disease control.
• Anti-tumor activity was also observed in heavily pre-treated patients with renal cell carcinoma (RCC), bladder cancer, head and neck squamous cell carcinoma (HNSCC) and non-small cell lung cancer (NSCLC) whose tumors had progressed through checkpoint inhibitors.

AU-007 and low-dose, subcutaneous aldesleukin continues to demonstrate a unique pharmacodynamic (PD) profile in the IL-2 class.

• A decrease in Tregs appears to be a critical determinant of observed efficacy, with greater median decreases observed in patients receiving one loading dose of low-dose, subcutaneous aldesleukin compared to low-dose, subcutaneous aldesleukin administered Q2W. Based on the Treg reduction levels and other PD findings, the company has made the decision to use the loading dose rather than the Q2W schedule of subcutaneous aldesleukin going forward.
• Greater decreases in Tregs on treatment is associated with longer progression-free survival (PFS) across the Phase 1 and Phase 2 portions of the AU-007 trial. Patients with a Treg cell reduction greater than the median of 43% had longer PFS outcomes than those with a Treg cell reduction less than the median of 43%.

The Phase 2 expansion cohorts evaluating AU-007 and low-dose, subcutaneous aldesleukin continue to enroll patients, with a focus on melanoma and non-small cell lung cancer. An additional Phase 2 cohort will evaluate AU-007 and low-dose, subcutaneous aldesleukin combined with avelumab (checkpoint inhibitor; anti-PD-L1) in NSCLC. The company anticipates presenting updated clinical data in the first half of 2025.

The poster, “A phase 1/2 dose escalation and cohort expansion study of AU-007, a human monoclonal antibody (mAb) that binds to IL-2 and inhibits CD25 binding, plus low-dose aldesleukin in advanced solid tumors,” (Abstract 685) is available to meeting registrants as an electronic poster on the SITC 2024 virtual meeting platform. It will be presented in a poster session on Friday, November 8, 2024, 9:00 a.m.-7:00 p.m. CST in Exhibit Halls AB.

The poster presentation is also available on the Aulos Bioscience website in the Abstracts and Publications section.

To learn more about the AU-007 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 AU-007

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, AU-007 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. AU-007 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 best-in-class IL-2 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, 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 field of artificial intelligence, antibody development and cancer immunotherapies. For more information, visit www.aulosbio.com, X (@AulosBioscience) and LinkedIn.

Fonte: Business Wire