Ph. I/II Sodium Thiosulfate for OtoProtection During Cisplatin (STOP-CIS)

Phase I/II Open Label Trial of Intravenous Sodium Thiosulfate (Pedmark®) as Otoprotectant in Adults Receiving Cisplatin Chemotherapy (STOP-CIS)

The purpose of this study is to assess the safety and effectiveness of a drug called Pedmark® sodium thiosulfate (STS) in reducing hearing impairment with standard of care cisplatin therapy. The safety and effectiveness of STS in reducing hearing loss has been well established in children and is approved for use in the pediatric and young adult population. However, information in adult patients is limited. As most cisplatin is administered in the adult population, this investigation would be of benefit.

Study Overview

• Status: Recruiting
• Conditions: Head and Neck Cancer; Thoracic Cancer; Testicular Cancer; Solid Tumor Malignancies
• Intervention / Treatment: Drug: Pedmark® STS

• Study Type: Interventional
• Enrollment (Estimated): 25
• Phase: Phase 2; Phase 1

Contacts and Locations

• Study Contact: Name: Michele Chu-Pilli; Phone Number: 520-626-1183; Email: chum@arizona.edu
• Study Contact Backup: Name: Alejandro Recio Boiles, MD; Phone Number: 520-694-2873; Email: areciomd@arizona.edu

Study Locations

• United States
  • Arizona
    • Tucson, Arizona, United States, 85724
      • Recruiting
      • University of Arizona Cancer Center
      • Principal Investigator: Alejandro Recio-Boiles, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Participants have provided informed consent prior to initiation of any study-specific activities.
• At least 18 years of age, male and female, at the time of signing the informed consent.
• ECOG Performance Status 0-1
• Histologically or cytologically confirmed treatment-naïve cancer.
• Scheduled to receive an FDA-approved, on-label indication, standard of care systemic cisplatin-based regimen (at least 200 mg/m2 cumulative dose) for any untreated any solid malignancy deemed by the treating physician

Exclusion Criteria:

• Prior cisplatin exposure due to a cancer treatment history
• Concurrent ototoxic medication unable to be safely discontinued or switched to a non-toxic alternative
• Planned radiation to the head or neck prior to, during, or within 3 months of completion of cisplatin
• History of severe hypersensitivity to sulfite, sodium thiosulfate, or any components
• Baseline serum sodium > 145 mmol/L or any grade ≥ 3 electrolyte abnormality
• Cisplatin infusion duration greater than 6 hours
• Females during pregnancy or breastfeeding, and childbearing potential, unwilling to use a method of contraception during treatment
• Male subjects with a pregnant partner who are unwilling to practice abstinence or use a condom during treatment
• Subject likely not to be available to complete all protocol-required study visits or procedures, and/or to comply with all required study procedures (i.e., Clinical Outcome Assessments) to the best of the subject's and investigator's knowledge.
• History or evidence of any other clinically significant disorder, condition, or disease (with the exception of those outlined above) that, in the opinion of the investigator, if consulted, would pose a risk to subject safety or interfere with the study evaluation, procedures, or completion.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Study Treatment Arm; Study participants will receive Pedmark® STS via intravenous infusion after the completion of their standard of care cisplatin infusion.	Drug: Pedmark® STS; Pedmark® STS (20 g/m2) will be given via intravenous infusion over 15-30 minutes, starting 6 hours after the completion of cisplatin infusion. Pedmark® STS will be given each day of cisplatin infusion.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Efficacy of intravenous STS to reduce hearing impairment associated with cisplatin	Proportion of participants with Brock grade ≥1 hearing loss determined from audiometry exams. The Brock ototoxicity classification and grading scale are as follows: Grade 0 = hearing threshold less than 40 dB HL at all test frequencies; Grade 1 = hearing threshold greater than or equal to 40 dB HL at 8 kHz only; Grade 2 = hearing threshold greater than or equal to 40 db HL at 4kHz and above; Grade 3 = hearing threshold greater than or equal to 40 dB HL at 2 kHz and above; Grade 4 = hearing threshold greater than or equal to 40 dB HL at 1 kHz and above.	Baseline, after cumulative cisplatin dose (≥ 200 mg/m2), and at 3 months following the conclusion of cisplatin chemotherapy treatment.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Tolerability of the administration of STS based on the adverse events	Overall safety profile characterized by the type, frequency, severity, duration, and relationship to STS of any adverse events.	At the end of treatment, up to 12 months from baseline.
Tolerability of the administration of STS: emetic control.	Emetic control (episodes nausea and/or vomiting) will be documented during the clinic visit or hospital stay as per standard practice and assessed using the MASCC Antiemesis Tool (MAT).	At the end of treatment, up to 12 months from baseline.
Cisplatin pharmacokinetics: area under the plasma concentration versus time curve (AUC)	A noncompartmental pharmacokinetic analysis of total and unbound cisplatin will be performed with Phoenix WinNonlin v8.5 (Certara), using a linear method to calculate the area under the plasma concentration versus time curve (AUC) at 4 and 6 hours post-cisplatin dose at the first study treatment visit.	At the first study treatment visit
Cisplatin pharmacokinetics: peak plasma concentration (Cmax)	A noncompartmental pharmacokinetic analysis of total and unbound cisplatin will be performed with Phoenix WinNonlin v8.5 (Certara), using a linear method to calculate the peak plasma concentration (Cmax) at 4 and 6 hours post-cisplatin dose at the first study treatment visit.	At the first study treatment visit
Cisplatin pharmacokinetics: elimination rate constant	A noncompartmental pharmacokinetic analysis of total and unbound cisplatin will be performed with Phoenix WinNonlin v8.5 (Certara), using a linear method to calculate the elimination rate constant at 4 and 6 hours post-cisplatin dose at the first study treatment visit.	At the first study treatment visit
Cisplatin pharmacokinetics: half-life	A noncompartmental pharmacokinetic analysis of total and unbound cisplatin will be performed with Phoenix WinNonlin v8.5 (Certara), using a linear method to calculate the half-life at 4 and 6 hours post-cisplatin dose at the first study treatment visit.	At the first study treatment visit
Cisplatin pharmacokinetics: total body clearance	A noncompartmental pharmacokinetic analysis of total and unbound cisplatin will be performed with Phoenix WinNonlin v8.5 (Certara), using a linear method to calculate the total body clearance at 4 and 6 hours post-cisplatin dose at the first study treatment visit.	At the first study treatment visit

Collaborators and Investigators

• Sponsor: University of Arizona
• Collaborators: Fennec Pharma
• Investigators: Study Chair: Lisa Davis, PharmD, University of Arizona; Principal Investigator: Alejandro Recio-Boiles, MD, University of Arizona

Study record dates

Study Major Dates

• Study Start (Actual): May 18, 2026
• Primary Completion (Estimated): April 30, 2028
• Study Completion (Estimated): April 30, 2028

Study Registration Dates

• First Submitted: February 2, 2026
• First Submitted That Met QC Criteria: February 9, 2026
• First Posted (Actual): February 12, 2026

Study Record Updates

• Last Update Posted (Actual): June 5, 2026
• Last Update Submitted That Met QC Criteria: June 4, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: Cancer; Adults; Cisplatin; Solid Tumor; Hearing Impairment; Sodium Thiosulfate; Otoprotectant
• Additional Relevant MeSH Terms: Urogenital Diseases; Genital Diseases; Neurologic Manifestations; Endocrine System Diseases; Nervous System Diseases; Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Genital Diseases, Male; Male Urogenital Diseases; Endocrine Gland Neoplasms; Gonadal Disorders; Otorhinolaryngologic Diseases; Sensation Disorders; Ear Diseases; Hearing Disorders; Testicular Diseases; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Neoplasms; Head and Neck Neoplasms; Hearing Loss; Testicular Neoplasms
• Other Study ID Numbers: STUDY00006997

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No