TRK* fusion proteins are key oncogenic drivers for various tumor types1,2

Comprehensive tumor profiling can help uncover actionable genomic alterations, such as NTRK gene fusions3,4

In TRK fusion cancers, the NTRK* gene (NTRK1, NTRK2, NTRK3) fuses with an unrelated gene2,5,6
*NSCLC, non–small cell lung cancer; NTRK, neurotrophic receptor tyrosine kinase; TRK, tropomyosin receptor kinase.
  • This fusion causes the expression of constitutively activated chimeric TRK fusion proteins, which results in cell proliferation and tumor growth leading to TRK fusion cancer7
  • NTRK gene fusions have been identified across many different kinds of solid tumors, rarely in common cancers, such as NSCLC,* and more often in rare cancers, such as infantile fibrosarcoma8,9
See the Interactive PI See the Interactive PI

Indication

VITRAKVI is indicated for the treatment of adult and pediatric patients with solid tumors that:

  • have a neurotrophic receptor tyrosine kinase (NTRK) gene fusion without a known acquired resistance mutation,
  • are metastatic or where surgical resection is likely to result in severe morbidity, and
  • have no satisfactory alternative treatments or that have progressed following treatment.

This indication is approved under accelerated approval based on overall response rate and duration of response. Continued approval for this indication may be contingent upon verification and description of clinical benefit in confirmatory trials.

Important Safety Information

Neurotoxicity: Among the 176 patients who received VITRAKVI, neurologic adverse reactions of any grade occurred in 53% of patients, including Grade 3 and Grade 4 neurologic adverse reactions in 6% and 0.6% of patients, respectively. The majority (65%) of neurologic adverse reactions occurred within the first three months of treatment (range 1 day to 2.2 years). Grade 3 neurologic adverse reactions included delirium (2%), dysarthria (1%), dizziness (1%), gait disturbance (1%), and paresthesia (1%). Grade 4 encephalopathy (0.6%) occurred in a single patient. Neurologic adverse reactions leading to dose modification included dizziness (3%), gait disturbance (1%), delirium (1%), memory impairment (1%), and tremor (1%).

Advise patients and caretakers of these risks with VITRAKVI. Advise patients not to drive or operate hazardous machinery if they are experiencing neurologic adverse reactions. Withhold or permanently discontinue VITRAKVI based on the severity. If withheld, modify the VITRAKVI dose when resumed.

Hepatotoxicity: Among the 176 patients who received VITRAKVI, increased transaminases of any grade occurred in 45%, including Grade 3 increased AST or ALT in 6% of patients. One patient (0.6%) experienced Grade 4 increased ALT. The median time to onset of increased AST was 2 months (range: 1 month to 2.6 years). The median time to onset of increased ALT was 2 months (range: 1 month to 1.1 years). Increased AST and ALT leading to dose modifications occurred in 4% and 6% of patients, respectively. Increased AST or ALT led to permanent discontinuation in 2% of patients.

Monitor liver tests, including ALT and AST, every 2 weeks during the first month of treatment, then monthly thereafter, and as clinically indicated. Withhold or permanently discontinue VITRAKVI based on the severity. If withheld, modify the VITRAKVI dosage when resumed.

Embryo-Fetal Toxicity: VITRAKVI can cause fetal harm when administered to a pregnant woman. Larotrectinib resulted in malformations in rats and rabbits at maternal exposures that were approximately 11- and 0.7-times, respectively, those observed at the clinical dose of 100 mg twice daily.

Advise women of the potential risk to a fetus. Advise females of reproductive potential to use an effective method of contraception during treatment and for 1 week after the final dose of VITRAKVI.

Most Common Adverse Reactions (≥20%): The most common adverse reactions (≥20%) were: increased ALT (45%), increased AST (45%), anemia (42%), fatigue (37%), nausea (29%), dizziness (28%), cough (26%), vomiting (26%), constipation (23%), and diarrhea (22%).

Drug Interactions: Avoid coadministration of VITRAKVI with strong CYP3A4 inhibitors (including grapefruit or grapefruit juice), strong CYP3A4 inducers (including St. John’s wort), or sensitive CYP3A4 substrates. If coadministration of strong CYP3A4 inhibitors or inducers cannot be avoided, modify the VITRAKVI dose as recommended. If coadministration of sensitive CYP3A4 substrates cannot be avoided, monitor patients for increased adverse reactions of these drugs.

Lactation: Advise women not to breastfeed during treatment with VITRAKVI and for 1 week after the final dose.

For important risk and use information about VITRAKVI, please see the full Prescribing Information.

You are encouraged to report side effects or quality complaints of products to the FDA by visiting www.fda.gov/medwatch or calling 1-800-FDA-1088.
For Bayer products you can report these directly to Bayer by clicking here.

References:

  • 1. Okimoto RA, Bivona TG. Tracking down response and resistance to TRK inhibitors. Cancer Discov. 2016;6(1):14-16.
  • 2. Vaishnavi A, Le AT, Doebele RC. TRKing down an old oncogene in a new era of targeted therapy. Cancer Discov. 2015;5(1):25-34.
  • 3. Hechtman JF, Benayed R, Hyman DM, et al. Pan-trk immunohistochemistry is an efficient and reliable screen for the detection of NTRK fusions. Am J Surg Pathol. 2017;41(11):1547-1551.
  • 4. Fox AJ, Hiemenz MC, Lieberman DB, et al. Next generation sequencing for the detection of actionable mutations in solid and liquid tumors. J Vis Exp. 2016;(115):e52758. doi:10.3791/52758.
  • 5. Kumar-Sinha C, Kalyana-Sundaram S, Chinnaiyan AM. Landscape of gene fusions in epithelial cancers: seq and ye shall find. Genome Med. 2015;7:129. doi:10.1186/s13073-015-0252-1.
  • 6. Latysheva NS, Oates ME, Maddox L, et al. Molecular principles of gene fusion mediated rewiring of protein interaction networks in cancer. Mol Cell. 2016;63(4):579-592.
  • 7. Amatu A, Sartore-Bianchi A, Siena S. NTRK gene fusions as novel targets of cancer therapy across multiple tumour types. ESMO Open. 2016;1(2):e000023.
  • 8. Stransky N, Cerami E, Schalm S, Kim JL, Lengauer C. The landscape of kinase fusions in cancer. Nat Commun. 2014;5:4846. doi:10.1038/ncomms5846.
  • 9. Bourgeois JM, Knezevich SR, Mathers JA, Sorensen PHB. Molecular detection of the ETV6-NTRK3 gene fusion differentiates congenital fibrosarcoma from other childhood spindle cell tumors. Am J Surg Pathol. 2000;24(7):937-946.