Combination of CB101 and radiation therapy in head and neck squamous cell carcinoma - Curebiotech, Inc., FOA # PA-21-262 Application number 1121483
PROJECT SUMMARY
Head and neck squamous cell carcinoma (HNSCC) is the seventh leading cause of cancer-related
mortality in the world. Radiation therapy (RT) is routinely used for patients with locoregionally advanced
disease. The historical 5-year overall survival rates for locally advanced HNSCC after treatment with surgery,
chemotherapy, and RT is ~50%. Many of these patients relapse after initial therapy and/or develop metastatic
disease, and the prognosis for these patients remains poor, with a median survival between 6 to 12 months.
Immunotherapy with anti-PD-1 antibodies yields a response rate less than 20%. Hence, there is a pressing
clinical need to develop alternative approaches for patients with relapsed and/or metastatic HNSCC.
CureBiotech Inc. is a preclinical stage biotech company that focuses on toll-like receptor 7/8 agonist,
resiquimod. Resiquimod is more potent and has better bioavailability than imiquimod, an FDA approved
immune modulating drug. CureBiotech has developed an innovative intratumoral controlled release formulation
of resiquimod, CB101, which sequesters the drug to a local site using a polymer matrix, with the aim of
avoiding systemic adverse immune response. It showed superior treatment efficacy over unformulated
resiquimod in multiple preclinical models. Locally advanced or relapsed HNSCC is easily accessible for
intratumoral injection of CB101. We postulate that CB101 will significantly augment the response of cancers to
RT via modulating the tumor microenvironment (TME). In Aim 1, we will optimize dose and treatment schedule
of CB101 and RT in HNSCC pre-clinical models. Since RT may increase PD-L1 expression on tumor cells, in
Aim 2, we will investigate the treatment efficacy of anti-PD-1 antibodies with CB101/RT combination. We
expect that lower doses of RT with CB101 may yield the same or better results as higher dose radiation alone
but with reduced toxicity, making RT resistant tumors sensitive and enhancing the abscopal effect of RT.
Successful completion of these aims will have a direct impact on the design of future clinical trials. We have
the scientific and personnel capability to achieve these aims quickly and meticulously. The data generated in
this project will be included in an IND application of a phase I clinical trial of CB101/RT in HNSCC patients to
the FDA.