Autologous Muscle Derived Cells for Treatment of Tongue Dysphagia

The primary objective of this double-blind, randomized, placebo-controlled, multicenter clinical trial is to evaluate the safety of AMDC-GIR during the 24 months following 2 consecutive treatments of tongue dysphagia in male and female patients who have undergone surgery and/or chemo- and/or radiotherapy for squamous cell cancer of the oropharynx.

The purpose of this double-blind, randomized, placebo-controlled, multicenter clinical trial is to evaluate the safety and efficacy of Autologous Muscle Derived Cells for Gastro-Intestinal Repair (AMDC-GIR) for the treatment of tongue dysphagia (TD) in male and female patients who have undergone surgery and/or chemo- and/or radiotherapy for squamous cell cancer of the oropharynx.

Surgery, chemo- and radiotherapy induce significant TD and result in long-term swallowing dysfunction. The incidence of TD after treatment for cancer of the pharynx exceeds 80%. Therefore, augmenting tongue muscle function may be beneficial to patients. Autologous muscle cell therapy, which involves isolation of cells from skeletal muscle biopsies, ex vivo expansion, and subsequent injection into the tongue, may serve as a durable therapy. In animal studies, muscle derived cells have successfully integrated within tissue to improve tongue strength and function. Intramuscular injection of AMDC-GIR has been shown to produce localized tissue changes at the injection site without a systemic effect. Initial results of a Phase 1 open label trial suggest that 150 x 10⁶ AMDC-GIR for the treatment of TD is safe and may be efficacious. A Phase I/II placebo controlled, randomized clinical trial is warranted.

Patients will receive two treatments of intramuscular injection of 1 AMDC-GIR dose of 150 x 10⁶ cells or identical placebo. For entrance into the study, patients must meet the study inclusion criterion and must not meet any of the exclusion criteria. Patients will have quantitative and qualitative measures of swallowing impairment assessed before treatment and at prescheduled intervals after treatment.

The study will treat 62 patients at 2 clinical sites: UC Davis Center for Voice and Swallowing and UCSF Voice and Swallowing Center. Patients will be randomized 1:1 to receive either 2 AMDC-GIR doses of 150 x 10⁶ cells or 2 doses of identical placebo composed of the same cryopreservation medium used for AMDC-GIR. Enrollment is expected to be completed within 2 years of initiating the study. Patients will be followed for 24 months post-treatment.

Male and female patients at least 18 years of age who have undergone surgery and/or chemo- and/or radiotherapy for primary treatment of oropharyngeal squamous cell cancer and who present with symptoms and findings of TD will be eligible for participation. Eligible patients will have muscle tissue harvested using an established needle biopsy technique during an outpatient procedure.

The harvested muscle will be placed in a hypothermic medium and transported to the manufacturer for cell processing. The muscle derived cells (MDC) will be isolated and expanded in culture over several weeks to a final AMDC-GIR dose of 150 x 10⁶ cells. Each patient will receive 2 doses of cells or placebo spaced 4-6 weeks apart.

After reaching the desired concentration, the isolated and expanded AMDC-GIR or identical placebo will be frozen and shipped back to the investigating physician. The investigative team will thaw the AMDC-GIR and dilute the sample with an equal volume of physiological saline. Under direct vision, the resulting suspension will be injected into the patient's tongue in a brief outpatient procedure for the patients randomized to the treatment arm. Patients randomized to receive placebo will undergo an identical procedure utilizing a thawed solution of frozen media without cells. Both patient and clinician will be blind to the treatment and placebo status.

Patients will be assessed for improvement in TD at 6 months, 12 months and 18 months and 24 months following treatment. Adverse events will be assessed at those visits, as well as during virtual visits at 1-2 days, 1 week, 4 weeks, 3 months, 15 months, 21 months and 24 months. Adverse events will also be assessed at 6 months post-injection in patients who were in the placebo group and elected to receive AMDC_GIR injections after the unblinding. Patient reported outcome measures will be assessed at 4 weeks, 3 months, 6 months, 12 months, 18 months and 24 months.