Melbourne ENT surgeon Professor Stephen O’Leary has revealed encouraging results from a trial of cochlear implant patients who received drug treatment to preserve residual hearing.
He reported “clinically significant effects” in the preservation of residual hearing after cochlear implantation in adult patients who received an oral drug, SENS-401, twice daily for a week before surgery and for seven weeks afterwards.
After seven weeks of treatment with SENS-401 (and six weeks after cochlear implantation), the study revealed the reduction in residual hearing loss was “systematically better at all frequencies” in the treated group than the placebo group.
This protective effect was also observed eight weeks after stopping treatment (14 weeks post-cochlear implantation).
Results showed 40% of SENS-401 treated patients showed complete hearing preservation compared to 0% in the control group.
Prof O’Leary, the Head of Otorhinolaryngology at The University of Melbourne and The Royal Victorian Eye and Ear Hospital, revealed details of the phase 2a clinical trial at the 36th World Congress of Audiology (WCA) in Paris in September 2024.
“The final results of the SENS-401 3 Phase 2a study are very encouraging as they support the conclusion that the administration of SENS-401 preserves residual hearing in patients undergoing cochlear implantation,” he said.
“This represents a crucial step for cochlear implantation candidates as residual hearing is very important to maintain and improve the quality of hearing of such patients.
“Residual hearing loss usually occurs mainly in the first six months after surgery; thus, early action is crucial.
“These positive data encourage us to pursue the clinical development of SENS-401, in order to offer innovative therapeutic treatments to patients scheduled for cochlear implantation as the level of residual hearing preservation showed in the study means patients have a better chance of understanding speech against background noise and perceiving more natural sound quality with speech and sounds.”
Sensorion biotechnology company, which specialises in development of therapies to restore, treat and prevent hearing, said the data validated the favourable safety profile of its therapy, SENS-401 in treated patients, in line with previous studies of 125 patients exposed to SENS-401.
“These positive results strongly support the continuation of the clinical development of SENS-401 for hearing preservation in treated patients,” it said.
Ms Nawal Ouzren, CEO of Sensorion, said she was very pleased with the progress made with the SENS-401 portfolio.
“We have reported the final results, including the positive secondary efficacy endpoints, of our Phase 2a clinical trial for the preservation of residual hearing, developed in collaboration with Cochlear Limited,” she said.
Significant effects on preservation
Prof O’Leary and ENT surgeon Professor Christophe Vincent from Salengro Hospital, France, reported on the final data analysis of the Phase 2a clinical trial at a symposium at the WCA sponsored by Sensorion, entitled ‘Treating hearing loss: Are we at the dawn of a therapeutic revolution?’
They said analysis showed “clinically significant effects” on the preservation of residual hearing in patients treated with the small molecule treatment compared to the control group.
The trial in association with cochlear implantation is a multicentre, randomised, controlled open-label trial aimed at evaluating the presence of SENS-401 in the cochlea (perilymph) after seven days of twice-daily oral administration in adults before cochlear implantation due to moderately severe to profound hearing impairment.
Patients start treatment a week before implantation and continue for a further 42 days.
The study is now completed with the last patient having completed the follow-up period. Of 16 patients in the trial, seven were treated with SENS-401 and nine were in the control group.
The open-label trial was designed to assess the presence of SENS-401 in the perilymph after the drug treatment in adult participants over 18 years old undergoing cochlear implantation.
On March 11, 2024, Sensorion confirmed the presence of SENS-401 in the perilymph at levels compatible with potential therapeutic efficacy in all patients seven days after the start of treatment. These results demonstrated that SENS-401 administered orally crossed the labyrinth barrier and confirmed that the primary endpoint was met, it said.
The study design also included several secondary endpoints, notably the change of hearing threshold from baseline to the end of the treatment period in the implanted ear at several frequencies. Study entry criteria required patients to have a pure tone audiometry (PTA) threshold of 80 dB or better (i.e., ≤80 dB) at 500 Hz, indicating a minimal level of residual hearing.
