Question: Is selumetinib effective in thyroid cancer?

Context:
A phase I trial of vertical inhibition of IGF signalling using cixutumumab, an anti-IGF-1R antibody, and selumetinib, an MEK 1/2 inhibitor, in advanced solid tumours.
BACKGROUND: We completed a phase I clinical trial to test the safety and toxicity of combined treatment with cixutumumab (anti-IGF-1R antibody) and selumetinib (MEK 1/2 inhibitor).
Two patients achieved a partial response (one unconfirmed), including a patient with BRAF wild-type thyroid carcinoma, and a patient with squamous cell carcinoma of the tongue, and six patients achieved time to progression of>6 months, including patients with thyroid carcinoma, colorectal carcinoma, and basal cell carcinoma.
CONCLUSIONS: Our study of anti-IGF-1R antibody cixutumumab and MEK 1/2 inhibitor selumetinib showed that the combination is safe and well-tolerated at these doses, with preliminary evidence of clinical benefit and pharmacodynamic evidence of target inhibition.
MHC class I loss is a frequent mechanism of immune escape in papillary thyroid cancer that is reversed by interferon and selumetinib treatment in vitro.
Increased antigenicity following selumetinib and IFN treatment warrants further study for immunotherapy of progressive PTC.
The role of KIs in differentiated TC may be revolutionised by the finding that selumetinib may restore a clinical response to radioactive iodine (RAI). 
BACKGROUND AND AIM: Selumetinib is a promising and interesting targeted therapy agent as it may reverse radioiodine uptake in patients with radioiodine-refractory differentiated thyroid cancer.
CONCLUSIONS: Compared with current chemotherapy, selumetinib has modest clinical activity as monotherapy in patients with advanced cancer, but combinations of selumetinib with cytotoxic agents in patients with BRAF or KRAS mutations hold great promise for cancer treatment.
Selumetinib may be an effective redifferentiating agent and could be used within several years.
Selumetinib-enhanced radioiodine uptake in advanced thyroid cancer.
METHODS: We conducted a study to determine whether the MAPK kinase (MEK) 1 and MEK2 inhibitor selumetinib (AZD6244, ARRY-142886) could reverse refractoriness to radioiodine in patients with metastatic thyroid cancer. 
Selumetinib increased the uptake of iodine-124 in 12 of the 20 patients (4 of 9 patients with BRAF mutations and 5 of 5 patients with NRAS mutations).
CONCLUSIONS: Selumetinib produces clinically meaningful increases in iodine uptake and retention in a subgroup of patients with thyroid cancer that is refractory to radioiodine; the effectiveness may be greater in patients with RAS-mutant disease. 
ECENT FINDINGS: For patients with advanced differentiated thyroid cancers, sorafenib, selumetinib, pazopanib and sunitinib have been investigated with promising results. 
Selumetinib is a promising and interesting targeted therapy agent as it may reverse radioiodine uptake in patients with radioiodine-refractory differentiated thyroid cancer.
Selumetinib may be an effective redifferentiating agent and could be used within several years.
Here, selumetinib targets the mitogen-activated protein kinase pathway in papillary thyroid carcinoma and shows limited single-agent activity in the patients with tumors that harbor the (V600E)BRAF mutation.
CONCLUSIONS: Selumetinib produces clinically meaningful increases in iodine uptake and retention in a subgroup of patients with thyroid cancer that is refractory to radioiodine; the effectiveness may be greater in patients with RAS-mutant disease. 

Answer: Yes, selumetinib was shown to be effective treatment for thyroid cancer. Selumetinib may reverse radioiodine uptake in patients with radioiodine-refractory differentiated thyroid cancer. Clinical efficacy of selumetinib was also investigated in other solid tumors.
Exact answer: yes