Sound Pharmaceuticals Gets $1.6 Million to Test SPI-1005 as CF Hearing Loss Therapy

Sound Pharmaceuticals has received a $1.6 million Cystic Fibrosis Foundation Therapeutics (CFFT) grant to test a therapy it has developed to improve hearing loss in cystic fibrosis (CF) patients being treated with tobramycin.

Tobramycin is an antibiotic used to treat flare-ups in CF patients’ lung problems that are known as acute pulmonary exacerbations. It is also used to treat lung infections in CF patients.

But one of tobramycin’s major side effects is inner ear damage that can lead to hearing loss. Sound Pharmaceuticals developed SPI-1005 to address that loss.

CF patients are particularly vulnerable to hearing loss, or ototoxicity, because early in their life doctors begin treating them with repeated doses of tobramycin or other therapies, either by inhalation or injection. The repeated doses are what can lead to progressive or permanent inner ear damage.

Some patients experience moderate hearing loss that can be addressed with a hearing aid. In others, the loss is severe enough to require a cochlear implant.

SPI-1005 is an experimental drug designed to improve hearing loss and tinnitus — the perception of noise or ringing in the ears — in several conditions, including ototoxicity.

Sound plans a Phase 1b study of tobramycin’s impact on hearing and SPI-1005’s ability to address the issue. The STOP Ototoxicity study (NCT02819856) will investigate the incidence and severity of hearing loss, tinnitus, vertigo and dizziness in CF patients taking tobramycin. It will also evaluate whether SPI-1005 can address the problems.

The study will enroll 100 patients across the United States. Patrick Flume, MD, of the Medical University of South Carolina, an expert in CF and lung disease, will lead the study. Flume has contributed to the guidelines the CF Foundation drafted for the treatment of pulmonary exacerbations.

“This is the first comprehensive U.S. study of ototoxicity in the CF population, and we are pleased to be leading it,” said Flume in a news release.

“We are thrilled to have the support of the CF Foundation and Dr. Flume on this groundbreaking study of tobramycin-induced ototoxicity,” said Jonathan Kil, MD, co-founder, CEO and chief medical officer of Sound Pharmaceuticals.

CF is caused by mutations in the CFTR gene that encodes the CFTR protein. When faulty, the protein contributes to the accumulation of mucus in several organs, making them susceptible to infection.

In the lungs, excessive bacterial or fungal growth can lead to lung inflammation, which can have severe consequences. Such infections are often treated with antibiotics like tobramycin.