Aura Biosciences announced the release of positive interim data from its phase 2 study on belzupacap sarotalocan (bel-sar; AU-011) via a suprachoroidal (SC) route of administration for the treatment of patients with early-stage choroidal melanoma (CM).
Tell me about bel-sar.
Bel-sar is the company’s lead virus-like drug conjugate (VDC) therapy designed to be combined with an anti-cancer agent. It works by selectively targeting and destroying cancer cells, triggering the immune system to potentially create a long-lasting immunity for tumors.
What is being evaluated in this phase 2 trial?
The trial (NCT04417530) is evaluating the safety and preliminary efficacy of varying bel-sar doses for up to three treatment cycles (via SC administration) for early-stage CM. A total of 20 adult patients are being assessed in single-dose cohorts 1-6 (n = 6) and multiple-dose cohorts 4-6 (n = 14).
This isn’t the first data update on it though, right?
Correct. Aura previously reported positive interim data from the ongoing trial in November 2022. A significant reduction in tumor growth rate was observed, as well as a favorable safety profile for bel-sar.
Now talk about the latest data.
Patients in cohorts 5 (n = 3) and 6 (n = 8) received up to three cycles of therapy, with cohort 5 participants at 40 μg/dose and cohort 6 participants at 80 μg/dose (the highest dosage).
All patients in these cohorts exhibited active tumor growth at the start of the study, and were evaluated for tumor growth rate, tumor control, and visual acuity (VA) preservation at clinical endpoints throughout the trial.
Give me some numbers.
The cohort 5 and 6 participants—all of whom received three cycles of therapy and an average of 9 months of follow-up—showed a statistically significant reduction in tumor growth rate (-0.289 mm/yr, P=<0.0001), a 100% (8/8) tumor control rate, and a VA preservation rate of 88% (7/8).
Any adverse events?
Bel-sar’s overall tolerability rate was generally favorable with no treatment-related serious or significant adverse events (AEs) as of January 10, 2023. Treatment-related AEs were predominantly mild.
As announced in November 2022, Aura is planning a three-arm, masked design, global phase 3 trial for bel-sar. An estimated 75 adult patients with early-stage CM will be enrolled, all of whom will have had their tumor growth documented prior to the start of the trial.