Patient Selection

​Select patients for treatment with RETEVMO based on the presence of a RET gene fusion (NSCLC, thyroid cancer, or other solid tumors) or specific RET gene mutation (MTC) in tumor specimens [see Clinical Studies (14)]. Information on FDA-approved test(s) for the detection of RET gene fusions and RET gene mutations is available at: http://www.fda.gov/CompanionDiagnostics. An FDA-approved companion diagnostic test for the detection of RET gene fusions and RET gene mutations in plasma or in tumors other than NSCLC and thyroid cancer is not currently available.

Important Administration Instructions

RETEVMO may be taken with or without food unless coadministered with a proton pump inhibitor (PPI) [see Dosage and Administration (2.4), Clinical Pharmacology (12.3)].

Recommended Dosage

The recommended dosage of RETEVMO based on body weight is:

• Less than 50 kg: 120 mg
• 50 kg or greater: 160 mg

Take RETEVMO orally twice daily (approximately every 12 hours) until disease progression or unacceptable toxicity.

Swallow the capsules whole. Do not crush or chew the capsules.

Do not take a missed dose unless it is more than 6 hours until next scheduled dose.

If vomiting occurs after RETEVMO administration, do not take an additional dose and continue to the next scheduled time for the next dose.

Dosage Modifications for Concomitant Use of Acid-Reducing Agents

Avoid concomitant use of a PPI, a histamine-2 (H2) receptor antagonist, or a locally-acting antacid with RETEVMO [see Drug Interactions (7.1)]. If concomitant use cannot be avoided:

• Take RETEVMO with food when coadministered with a PPI.
• Take RETEVMO 2 hours before or 10 hours after administration of an H2 receptor antagonist.
• Take RETEVMO 2 hours before or 2 hours after administration of a locally-acting antacid.

Dosage Modifications for Adverse Reactions

The recommended dose reductions for adverse reactions are provided in Table 1.

Permanently discontinue RETEVMO in patients unable to tolerate three dose reductions.

The recommended dosage modifications for adverse reactions are provided in Table 2.

Dosage Modifications for Concomitant Use of Strong and Moderate CYP3A Inhibitors

Avoid concomitant use of strong and moderate CYP3A inhibitors with RETEVMO. If concomitant use of a strong or moderate CYP3A inhibitor cannot be avoided, reduce the RETEVMO dose as recommended in Table 3. After the inhibitor has been discontinued for 3 to 5 elimination half-lives, resume RETEVMO at the dose taken prior to initiating the CYP3A inhibitor [see Drug Interactions (7.1)].

Dosage Modification for Severe Hepatic Impairment

Reduce the recommended dosage of RETEVMO for patients with severe hepatic impairment as recommended in Table 4 [see Use in Specific Populations (8.7)].