Fennec Data Signals Hearing Hope for Adult Head & Neck Cancer Patients

RESEARCH TRIANGLE PARK, N.C. – February 20, 2026 – New real-world data presented this week offers a significant ray of hope for adult cancer survivors facing the debilitating and often permanent side effect of hearing loss from a cornerstone chemotherapy. Fennec Pharmaceuticals announced findings from a study suggesting its drug, PEDMARK® (sodium thiosulfate injection), can be safely and effectively used in adults with head and neck cancers to prevent hearing damage caused by cisplatin, without compromising the life-saving efficacy of the cancer treatment.

The data, shared as a digital poster at the 2026 Multidisciplinary Head and Neck Cancers Symposium in Palm Desert, California, represents a potentially pivotal moment for the company and for the broader field of oncology supportive care. While PEDMARK® is already approved for use in children, these findings mark the first promising real-world evidence of its utility in a large adult patient population, addressing what many experts call a critical and overlooked gap in cancer survivorship.

A Silent Side Effect with Loud Consequences

Cisplatin and other platinum-based chemotherapies have been instrumental in improving survival rates for patients with solid tumors, including head and neck, testicular, ovarian, and lung cancers. However, this success comes at a steep price for many. Ototoxicity, or drug-induced hearing damage, is a severe and well-documented side effect. Studies indicate that between 60% and 90% of patients treated with cisplatin experience some degree of permanent, irreversible hearing loss.

This damage can profoundly degrade a survivor's quality of life, impacting communication, social engagement, career potential, and mental health. For years, the trade-off has been largely accepted as an unavoidable consequence of curative treatment. While audiologic monitoring is recommended, preventative measures have been nonexistent for most adult patients, leaving them to manage the lifelong consequences with hearing aids or cochlear implants, which are costly and do not restore natural hearing.

“Cisplatin-induced hearing loss remains one of the most underrecognized yet deeply consequential toxicities associated with cancer treatment,” said Leslie Worona, an oncology nurse practitioner at Mount Sinai Hospital and a coauthor of the study, in a statement released by the company.

Promising Signals from Real-World Integration

The new data presented by Fennec stems from a multi-institutional retrospective review of 15 adults with head and neck cancers. The study's primary goal was to assess the feasibility of integrating PEDMARK® into existing treatment regimens. Clinicians administered the drug intravenously approximately six hours after the completion of each cisplatin infusion. This specific timing is critical; it is based on a validated approach intended to neutralize cisplatin in the bloodstream after it has exerted its anti-tumor effect, thereby protecting sensitive organs like the inner ear without interfering with the chemotherapy's cancer-killing activity.

The results were highly encouraging on multiple fronts. The study demonstrated that the six-hour-post-cisplatin administration schedule was not only safe but also operationally feasible and easily integrated into real-world care plans, whether in a clinic or via home infusion. Crucially, no disruption to the patients' curative-intent cisplatin treatment was observed.

Furthermore, the drug was well-tolerated, with only isolated, self-limited infusion events and no severe (Grade 3 or 4) toxicities reported. Most importantly, the study showed early signals of hearing preservation. The majority of patients who received PEDMARK®, including those who already had some level of hearing impairment before starting treatment, demonstrated no measurable hearing loss during or after their chemotherapy course.

“Head and neck cancer is one of the most common cancers globally, underscoring why these results are encouraging for clinicians,” noted Dr. Maria A. Velez, a clinical instructor at UCLA Health and coauthor of the study. She highlighted the drug's potential “to address cisplatin-induced hearing loss… without compromising cisplatin’s proven antitumor activity.”

Paving the Way for a New Standard of Care

The findings could accelerate a paradigm shift in oncology toward more holistic cancer care, where the long-term quality of life for survivors is given as much consideration as the immediate goal of curing the disease. PEDMARK® is currently the first and only therapy approved by the U.S. Food and Drug Administration (FDA) to reduce the risk of cisplatin-induced ototoxicity, but its indication is limited to pediatric patients one month of age and older with localized, non-metastatic solid tumors.

The National Comprehensive Cancer Network (NCCN) already provides a 2A recommendation for its use in adolescent and young adult patients, signaling a growing recognition of its benefits. However, a formal guideline for the much larger adult population has been absent. This new real-world evidence provides a powerful argument for expanding its use and could lay the groundwork for future updates to clinical practice guidelines for adult head and neck cancers.

“These new findings are critical to demonstrating the feasibility, scalability and long-term value of PEDMARK® beyond those studied in our pivotal clinical program,” stated Pierre S. Sayad, PhD, M.S., chief medical officer of Fennec Pharmaceuticals. “Additionally, these data may help to strengthen the case for broader clinical adoption in a sizable patient population at high risk for permanent hearing loss.”

Strategic Expansion and Market Opportunity

For Fennec Pharmaceuticals, a specialty company singularly focused on this issue, the data represents a significant strategic milestone. Successfully expanding PEDMARK's label to include adults would unlock a vastly larger market. With approximately 500,000 patients diagnosed annually in the U.S. with cancers that could be treated with platinum-based chemotherapy, the potential patient population is substantial.

The company has already established a commercial footprint. PEDMARK® received FDA approval in September 2022, and its European counterpart, PEDMARQSI, was approved in the European Union and the United Kingdom in 2023. Fennec has also secured a licensing agreement with Norgine to commercialize the drug in Europe, Australia, and New Zealand. With robust patent protection extending to 2039, the company is well-positioned to capitalize on a successful label expansion.

While larger, prospective clinical trials will likely be needed to confirm these early findings and support a formal regulatory submission for an adult indication, this real-world evidence provides a strong foundation. It demonstrates that a solution to a long-standing problem in cancer care is not only possible but practical, potentially changing the future for countless cancer survivors.