A Phase II Trial of Valproic Acid in Patients With Advanced Thyroid Cancers of Follicular Cell Origin

Summary

Background: * Patients who have advanced thyroid cancer have a low long-term survival rate. These types of thyroid cancer do not respond well to conventional surgery or radiation, or to specific thyroid cancer treatments such as radioactive iodine treatment and thyroid hormone for thyroid stimulating hormone (TSH) suppression. * Valproic acid has long been approved as an anticonvulsant to treat seizures in patients with epilepsy. It has also been used to treat bipolar disorder. Recent studies have shown that valproic acid has promising effects in thyroid cancer treatment because it may help destroy cancer cells and help conventional treatments be more effective. However, valproic acid is not approved for thyroid cancer and is therefore an investigational drug. Objectives: * To determine whether valproic acid can inhibit tumor growth or induce tumor cell death. * To determine whether valproic acid can make tumor cells increase their uptake of radioiodine. Eligibility: \- Individuals at least 18 years of age who have advanced-stage thyroid cancer that is either unresponsive to conventional treatments or fails to absorb radioiodine. Design: * Eligible participants will continue on the standard thyroid hormone suppression therapy and begin receiving valproic acid for a total of 10 weeks. Participants will keep a study diary to record doses and side effects, and will have regular clinic visits to provide blood samples and receive additional valproic acid. * After 10 weeks, participants will have a Thyrogen scan to measure radioiodine uptake after valproic acid therapy. Tumor biopsies and blood samples will be taken at this time. * If there is increased radioiodine uptake on the scan, participants will have additional radioiodine therapy. * If there is no increased uptake on the scan, participants will continue on valproic acid for 7 more weeks. After 16 total weeks of treatment, additional blood samples and scans will be taken. Participants may continue to take valproic acid if the thyroid cancer appears to be responding to the treatment. * Follow-up visits will be scheduled at 3, 6, 9 (for patients continuing on valproic acid only), and 12 months.

Timeline

Start

2010-09-24

Primary completion

2015-09-28

Completion

2016-04-28

Publications

• Background Davies L, Welch HG. Increasing incidence of thyroid cancer in the United States, 1973-2002. JAMA. 2006 May 10;295(18):2164-7. doi: 10.1001/jama.295.18.2164.
• Background Hundahl SA, Fleming ID, Fremgen AM, Menck HR. A National Cancer Data Base report on 53,856 cases of thyroid carcinoma treated in the U.S., 1985-1995 [see commetns]. Cancer. 1998 Dec 15;83(12):2638-48. doi: 10.1002/(sici)1097-0142(19981215)83:123.0.co;2-1.
• Background Goretzki PE, Simon D, Frilling A, Witte J, Reiners C, Grussendorf M, Horster FA, Roher HD. Surgical reintervention for differentiated thyroid cancer. Br J Surg. 1993 Aug;80(8):1009-12. doi: 10.1002/bjs.1800800826.
• Results Nilubol N, Merkel R, Yang L, Patel D, Reynolds JC, Sadowski SM, Neychev V, Kebebew E. A phase II trial of valproic acid in patients with advanced, radioiodine-resistant thyroid cancers of follicular cell origin. Clin Endocrinol (Oxf). 2017 Jan;86(1):128-133. doi: 10.1111/cen.13154. Epub 2016 Sep 8.

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