ASCO20: Can Radioiodine Plus Durvalumab Improve Outcomes in Resistant Thyroid Cancer?
Posted: Monday, June 22, 2020
The search for effective treatment options for patients with recurrent or metastatic radioiodine-refractory thyroid cancer continues. A small study presented as a poster session during the ASCO20 Virtual Scientific Program (Abstract 6587) suggests radioiodine therapy in combination with the anti–PD-L1 inhibitor durvalumab may represent a potential treatment for this patient population. “Durvalumab plus radioiodine is safe and well tolerated,” stated Bharat Burman, MD, PhD, of Memorial Sloan Kettering Cancer Center, New York, and colleagues.
Patients with at least one radioiodine-avid tumor on the most recent radioiodine scan or one tumor on FDG-PET scan were treated with durvalumab at 1,500 mg IV every 4 weeks with recombinant human TSH-stimulated radioiodine (100 mCi) during cycle 1. To assess safety, durvalumab-related dose-limiting toxicities were monitored for 6 weeks after the first dose in six patients. After no dose-limiting toxicities were observed, per protocol rules, all 11 patients were included in the trial, and 8 has received prior treatment.
The results revealed no dose-limiting toxicities and no durvalumab-related adverse events greater than grade 3. The most common nonlaboratory adverse events were cough, hypertension, pain, edema, and fatigue/nausea/diarrhea/arthralgia/dry skin/dyspnea/edema. As of February 20, two patients had a partial response to treatment, seven achieved stable disease, and two experienced disease progression. In addition, six patients were found to have tumor regression.
“The preliminary efficacy signal in this small cohort is promising,” Dr. Burman and colleagues concluded, and further research is needed to understand “how radioiodine plus PD-L1 targeting impacts the tumor immune microenvironment.”
Disclosure: For full disclosure of the study authors, visit coi.asco.org.