Pharmacy Prior Authorization Criteria

Thyrogen (thyrotropin alfa for injection)

Indications for Prior Authorization

Thyrogen (thyrotropin alfa for injection)

• For diagnosis of Adjunctive Diagnostic Tool for Serum Thyroglobulin Testing in Well Differentiated Thyroid Cancer
  Indicated for use as an adjunctive diagnostic tool for serum thyroglobulin (Tg) testing with or without radioiodine imaging in the follow-up of patients with well-differentiated thyroid cancer who have previously undergone thyroidectomy.

  Limitations of Use: Thyrogen-stimulated Tg levels are generally lower than, and do not correlate with, Tg levels after thyroid hormone withdrawal. Even when Thyrogen-stimulated Tg testing is performed in combination with radioiodine imaging, there remains a risk of missing a diagnosis of thyroid cancer or of underestimating the extent of disease. Anti-Tg antibodies may confound the Tg assay and render Tg levels uninterpretable. Therefore, in such cases, even with a negative or low-stage Thyrogen radioiodine scan, consideration should be given to further evaluating patients.

• For diagnosis of Adjunct to Treatment for Ablation in Well Differentiated Thyroid Cancer
  Indicated for use 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.

  Limitations of Use: The effect of Thyrogen on long-term thyroid cancer outcomes has not been determined. Due to the relatively small clinical experience with Thyrogen in remnant ablation, it is not possible to conclude whether long-term thyroid cancer outcomes would be equivalent after use of Thyrogen or use of thyroid hormone withholding for TSH elevation prior to remnant ablation.

Criteria

Thyrogen

Prior Authorization

Length of Approval: 1 course of therapy

• One of the following:
• Thyrogen is being used as a diagnostic tool for serum thyroglobulin testing in well differentiated thyroid cancer
OR
• All of the following:
• Thyrogen is being used as an adjunctive treatment for radioiodine ablation of thyroid tissue remnants
AND
• Patient has undergone a near-total or total thyroidectomy for well-differentiated thyroid cancer
AND
• Patient does not have evidence of distant metastatic thyroid cancer
AND
• One of the following:
• Patient is unable to tolerate thyroid hormone withdrawal (ie, intolerable hypothyroid symptoms) [1,2]
OR
• Thyroid hormone withdrawal is medically contraindicated (ie, exacerbation of comorbid conditions) [1,2]
OR
• Patient has inadequate thyroid stimulating hormone (TSH) response to thyroid hormone withdrawal [1]
OR
• Patient has an undetectable Tg on thyroid hormone suppressive therapy, to exclude the diagnosis of residual or recurrent thyroid cancer [1]

P & T Revisions

2024-04-04, 2022-03-28, 2021-09-28, 2021-09-27, 2021-05-25, 2020-03-12

References

1. Thyrogen Package Insert. Genzyme Corporation. Cambridge, MA. February 2023.
2. Cooper DS, Doherty GM, Haugen BR, et al. Revised American Thyroid Association Management Guidelines. For Patients with Thyroid Nodules and Differentiated Thyroid Cancer. Thyroid. 2009;19 (11):1167-1214.

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End Notes

1. Considerations in the Use of Thyrogen: [1] 1. Even when Thyrogen-stimulated Tg testing is performed in combination with radioiodine imaging, there remains a meaningful risk of missing a diagnosis of thyroid cancer or of underestimating the extent of disease. Therefore, thyroid hormone withdrawal Tg testing with radioiodine imaging remains the standard diagnostic modality to assess the presence, location, and extent of thyroid cancer. 2. Although Thyrogen appeared non-inferior to thyroid hormone withholding in a study of postsurgical thyroid remnant ablation, long-term clinical outcome data are limited. Due to the relatively small clinical experience with Thyrogen in remnant ablation, it is not possible to conclude whether long-term thyroid cancer outcomes would be equivalent after use of Thyrogen or use of thyroid hormone withholding for TSH elevation prior to remnant ablation. 3. Clinicians employ a wide range of 131I activities to achieve remnant ablation in patients who have been prepared by withholding of thyroid hormone. The primary study of Thyrogen for remnant ablation employed 100 mCi ± 10% in all patients. Data are inadequate to determine if a lower dose of radioiodine would be effective when Thyrogen is used as an adjunct to radioiodine in postsurgical thyroid remnant ablation. 4. Thyrogen Tg levels are generally lower than, and do not correlate with Tg levels after thyroid hormone withdrawal. 5. A newly detectable Tg level or a Tg level rising over time after Thyrogen, or a high index of suspicion of metastatic disease, even in the setting of a negative or low-stage Thyrogen radioiodine scan, should prompt further evaluation such as thyroid hormone withdrawal to definitively establish the location and extent of thyroid cancer. On the other hand, none of the 31 patients studied with undetectable Thyrogen Tg levels (< 2.5 ng/mL) had metastatic disease. Therefore, an undetectable Thyrogen Tg level suggests the absence of clinically significant disease. 6. The decisions whether to perform a Thyrogen radioiodine scan in conjunction with a Thyrogen serum Tg test and whether and when to withdraw a patient from thyroid hormone are complex. Pertinent factors in these decisions include the sensitivity of the Tg assay used, the Thyrogen Tg level obtained, and the index of suspicion of recurrent or persistent local or metastatic disease. In the clinical trials, combination Tg and scan testing did enhance the diagnostic accuracy of Thyrogen in some cases. 7. The signs and symptoms of hypothyroidism which accompany thyroid hormone withdrawal are avoided with Thyrogen.

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Revision History

• 2024-04-04: 2024 Annual Review: No criteria changes
• 2022-03-28: 2022 Annual Review - No changes to criteria, updated background information
• 2021-09-28: Updated GPI
• 2021-09-27: Addition of EHB formulary to guideline, no changes to criteria
• 2021-05-25: Addition of EHB formulary to guideline, no changes to
• 2020-03-12: Annual Review - No Changes

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