Vitrakvi Dosage

Patient Selection

Select patients for treatment with VITRAKVI based on the presence of a NTRK gene fusion in tumor specimens.

​In patients with secretory breast cancer, mammary analogue secretory cancer (MASC), congenital mesoblastic nephroma (CMN), or infantile fibrosarcoma, consider treatment without confirmation of NTRK rearrangements in tumor specimens.

Information on FDA-approved tests is available at http://www.fda.gov/companiondiagnostics.

Recommended Dosage

Dosage Modifications for Adverse Reactions

For Grade 2 and higher liver function test abnormalities, refer to Section 2.4, Table 2, Dosage Modifications for Hepatotoxicity.

For all other Grade 3 or 4 adverse reactions:

• Withhold VITRAKVI until adverse reaction resolves or improves to baseline or Grade 1. Resume at the next dosage modification if resolution occurs within 4 weeks.
• Permanently discontinue VITRAKVI if an adverse reaction does not resolve within 4 weeks.

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

Permanently discontinue VITRAKVI in patients who are unable to tolerate VITRAKVI after three dose modifications.

Dosage Modifications for Hepatotoxicity

The recommended dosage modifications for VITRAKVI liver function test abnormalities are provided in Table 2.

For CTCAE Grade 2 ALT and/or AST elevation, monitor liver function frequently as clinically indicated, to establish whether a dose interruption or reduction is required.

Dosage Modifications for Coadministration with Strong CYP3A4 Inhibitors

Avoid coadministration of strong CYP3A4 inhibitors with VITRAKVI. If coadministration of a strong CYP3A4 inhibitor cannot be avoided, reduce the VITRAKVI dose by 50%. After the inhibitor has been discontinued for 3 to 5 elimination half-lives, resume the VITRAKVI dose that was used prior to initiating the CYP3A4 inhibitor.

Dosage Modifications for Coadministration with Strong or Moderate CYP3A4 Inducers

Avoid coadministration of strong CYP3A4 inducers with VITRAKVI. If coadministration of a strong CYP3A4 inducer cannot be avoided, double the VITRAKVI dose. Additionally, for coadministration with a moderate CYP3A4 inducer, double the VITRAKVI dose. After the inducer has been discontinued for 3 to 5 elimination half-lives, resume the VITRAKVI dose that was used prior to initiating the CYP3A4 inducer.

Dosage Modifications for Patients with Hepatic Impairment

Reduce the starting dose of VITRAKVI by 50% in patients with moderate (Child-Pugh B) to severe (Child-Pugh C) hepatic impairment.

Administration

VITRAKVI capsule or oral solution may be used interchangeably.

Do not make up a missed dose within 6 hours of the next scheduled dose.

If vomiting occurs after taking a dose of VITRAKVI, take the next dose at the scheduled time.