Study to Evaluate Safety and Efficacy of DB-020 to Protect Hearing in Patients Receiving Cisplatin for Cancer Treatment

Cisplatin is a widely used and effective chemotherapy in the treatment of adult and pediatric solid tumors, including bladder, testicular, head and neck, and lung cancers. Serious side effects of cisplatin treatment include ototoxicity. To date, no approved therapy to prevent or treat ototoxicity exists for people receiving cisplatin treatment, which remains the most common dose-limiting side effect associated with cisplatin administration. Participants who will be undergoing cancer treatment with high doses of cisplatin every 21 or 28 days will receive IT injection with one ear receiving DB-020 and one ear receiving placebo during each administration. The study will comprise 2 parts. In Part A, eligible participants will be randomized to one of two doses of DB-020. In Part B, participants will be treated with a single dose of DB-020, as selected from data collected in Part A. In both Parts A and B, the ear receiving DB-020 or placebo will be randomized. The choice of dose in Part B will depend on the data from Part A. If appropriate safety and efficacy is observed at either dose level, the Sponsor has the option of dosing at one of these concentrations either unilaterally (ie, with placebo administered in the contralateral ear) or bilaterally (ie, open-label DB-020 administered to both ears) in Part B.