UPDATE-1-Auris' shares tank as it plans to end key trial for deafness drug

(Adds CEO comments, Auris Medical's shares)

Nov 28 (Reuters) - Auris Medical Holding AG's shares slumped more than 50 percent on Tuesday after it said it would end an ongoing late-stage study testing its treatment for sudden deafness, as the drug failed to improve hearing in patients in a related trial.

The drug developer was evaluating the drug, AM-111, in two late-stage studies called Healos and Assent.

Data from Healos showed that AM-111 was not statistically significant in improving hearing ability in the overall patient population, failing the main goal of the study.

Auris Medical was testing two doses of the drug - 0.4 mg and 0.8 mg - in patients with severe and profound sudden deafness, in comparison with a placebo.

The company also decided to end the Assent trial early as its Chief Executive Thomas Meyer told Reuters that it does not make sense to continue with the current design.

The separate Assent trial profile was similar to Healos as it also recruited and enrolled severe to profound hearing loss patients. Data from this study was expected in the second half of next year.

"The good news is really that we have ... exciting data in the subgroup of patients who are most in need of a treatment," Meyer added.

The company noted that the smaller dose of the drug did show some improvement in patients with acute hearing loss.

Meyer said the company would discuss with health regulators the improvement seen in some patients on the smaller dose.

Auris Medical's rival Otonomy Inc said on Monday it would stop commercialization of ear infection drug Otiprio, sending its shares up 14.8 percent to $6.20 in before the bell on Tuesday.

Otonomy said it planned to focus on developing other drugs in its pipeline, including the marketing application for its Meniere's disease drug in the United States.

Auris Medical's shares plunged to 38 cents in premarket trading. (Reporting by Divya Grover in Bengaluru; Editing by Martina D'Couto)