The U.S. Food and Drug Administration has revised the prescribing information (PI) for the use of Thyrogen (thyrotropin alfa for injection) to widen the dose range of radioiodine for patients with well-differentiated thyroid cancer being prepped for thyroid remnant ablation with the drug.
Thyrogen is used before radioiodine treatment to enhance the uptake of the radiotracer, allowing patients to avoid the adverse effects associated with hyperthyroidism (OT 3/25/14 issue). Physicians may now select a radioiodine dose between 30 and 100 mCi for patients who receive Thyrogen, whereas the dose was previously fixed at 100 mCi.
“The revised PI for Thyrogen provides a new option for many physicians who may be wanting to reduce radioiodine use due to uncertainty about impact of dosing on recurrences and mortality in low-risk patients as well as short- and long-term safety concerns,” Martin Schlumberger, MD, Professor of Oncology and Chair of the Department of Nuclear Medicine and Endocrine Oncology at the Gustave Roussy Cancer Center of University Paris Sud, said in a statement from the drug manufacturer.
The revised prescribing information is based on the results of two large prospective studies that compared ablation success in patients with differentiated thyroid cancer receiving Thyrogen and patients undergoing thyroid hormone withdrawal at both low and high doses of radioiodine. In both studies, patients receiving Thyrogen had fewer hypothyroid symptoms and better quality of life, than patients receiving thyroid hormone withdrawal.
Thyrogen is also approved as an adjunctive diagnostic tool for serum thyroglobulin testing with or without radioiodine imaging for patients with well-differentiated thyroid cancer. And, Thyrogen is approved in the U.S. and Europe as an adjunctive treatment for radioiodine ablation of thyroid tissue remnants in patients who have undergone a near total or total thyroidectomy for well-differentiated thyroid cancer and who do not have evidence of distant metastatic thyroid cancer.
The drug is marketed by Genzyme.