16 November 2021 - - US-based oncology company Aura Biosciences has presented data evaluating its first VDC, AU-011, in indeterminate lesions and choroidal melanoma, including final safety and efficacy data from the Phase 1b/2 trial using intravitreal administration, as well as updated safety results from the Phase 2 trial using suprachoroidal administration, the company said.

The results are presented as part of the American Academy of Ophthalmology 2021 annual meeting.

Final 12-Month Safety and Efficacy Data from Phase 1b/2 Trial with IVT administration
The Phase 1b/2 trial (NCT03052127) evaluated the safety and efficacy of AU-011 using IVT administration for the treatment of ILs and CM.

A total of 56 patients were enrolled in the Ph1b/2 trial including the single and multiple dose escalation cohorts and received up to two cycles of therapy (therapeutic regimen).

As part of an enrichment strategy agreed with FDA, patients with small tumors with active growth were enrolled in the Phase 2 part of the study (expansion cohort).

This group of patients received the therapeutic regimen and were evaluated for the tumor growth rate, tumor control, and visual acuity preservation as the efficacy endpoints.

These endpoints have been agreed with FDA and are planned to be used in the pivotal program.

The results at 12 months showed a statistically significant reduction in the tumor growth rate (-0.483 mm/yr, p = 0.018) compared to each patient's documented growth rate at study entry, and a 64% tumor control rate.

In addition, the visual acuity preservation rate was 71%, which is unprecedented compared to the current standard of care with radiotherapy.

Overall, AU-011 demonstrated a favorable safety and tolerability profile. The majority of adverse events, which included intraocular inflammation and increased intraocular pressure, were transient and resolved without clinical sequelae.

A large number of patients (43/56) had tumors close to the fovea and optic disk and only two patients with juxta-foveal tumors had a treatment related serious adverse event of vision loss. No other treatment related SAEs were observed in the trial.

These safety and efficacy results indicate that AU-011 may offer a targeted vision preserving therapy for the first line treatment of CM.

This Phase 2 trial (NCT04417530) includes an open-label, dose escalation phase assessing the safety and efficacy of AU-011 via SC administration in patients with ILs and CM and plans to enroll up to 22 patients.

In this preliminary safety data review of the initial dose escalation cohorts, no treatment related SAEs, dose limiting toxicities, or grade 3/4 AEs were reported.

Preliminary results indicate a positive safety and tolerability profile for AU-011 via SC administration.

Choroidal melanoma is a rare and aggressive type of eye cancer. Choroidal melanoma is the most common primary intraocular tumor in adults and develops in the uveal tract of the eye.

No targeted therapies are available at present, and current radiotherapy treatments can be associated with severe visual loss and other long-term sequelae such as dry eye, glaucoma, cataracts, and radiation retinopathy.

The most common current treatment is plaque radiotherapy, which involves surgical placement of a radiation device on the exterior of the eye over the tumor.

The alternative is enucleation, or total surgical removal of the eye. Choroidal melanoma metastasizes in approximately 50% of cases with liver involvement in 80-90% of cases and, unfortunately, metastatic disease is universally fatal.

There is a very high unmet need for a new vision sparing targeted therapy that could enable early treatment intervention for this life-threatening rare disease given the mortality rate in metastatic disease, lack of approved therapies, and the comorbidities of radioactive treatment options.

AU-011 is a first-in-class virus-like drug conjugate therapy in clinical development for the first line treatment of choroidal melanoma.

The virus-like component of the VDC selectively binds unique heparin sulphate proteoglycans (HSPGs), which are modified and overexpressed on the tumor cell surface of malignant cells in the choroid and AU-011 delivers a potent cytotoxic drug that is activated with infrared light.

Upon activation with an ophthalmic laser, the cytotoxic drug rapidly and specifically disrupts the cell membrane of malignant cells with a pro-immunogenic cell death that can activate the immune system generating long term anti-tumor immunity.

The unique specificity of tumor binding by the VDC enables the preservation of key eye structures, which may allow for the potential of preserving patients' vision and reducing other long-term complications of radiation treatment.

AU-011 can be delivered using equipment commonly found in an ophthalmologist's office and does not require a surgical procedure, pointing to a potentially less invasive, more convenient therapy for patients and physicians.

AU-011 for the treatment of choroidal melanoma is currently in Phase 2 clinical development and the company plans to expand the clinical program into choroidal metastasis.

The suprachoroidal space injection treatment approach offers unprecedented access to the back of the eye where sight-threatening disease often occurs.

Aura believes that delivering AU-011 into SCS within the eye, has the potential to offer certain advantages, including higher bioavailability at the tumor site and reduced exposure of non-targeted tissues, which may lead to an improved therapeutic index for AU-011.

Collectively, these features could allow for the treatment of a wider range of tumor sizes, and, therefore, a larger number of patients may be treatable. The company is partnered with Clearside Biomedical for use of Clearside's SCS Microinjector for administration of AU-011 into the SCS.

Aura Biosciences, Inc. is a clinical-stage oncology company developing a novel technology platform based on virus-like drug conjugates to target and destroy cancer cells selectively while activating the immune system to create long lasting anti-tumor immunity.