Vitrakvi (larotrectinib)

What is Vitrakvi (larotrectinib)?

Vitrakvi (larotrectinib) is a kinase inhibitor indicated for the treatment of adult and pediatric patients with solid tumors that^1,2:

• are caused by certain abnormal neurotrophic receptor tyrosine kinase (NTRK) gene¹,
• are metastatic or where surgical removal is likely to result in severe complications², and

have no satisfactory alternative treatments or that have progressed following treatment².

Who is Vitrakvi (larotrectinib) for?

Among all patients with solid tumors only those with an abnormal NTRK gene are eligible for treatment with Vitrakvi (larotrectinib).

To determine whether a patient harbours this genetic mutation two techniques are commonly used: next generation sequencing (NGS) or fluorescence in situ hybridisation (FISH)². NGS is a method used to resolve DNA sequence of an individual’s chromosome¹¹, whereas FISH is a method to locate the position of DNA sequences on chromosomes¹².

How does Vitrakvi (larotrectinib) work?

Vitrakvi (larotrectinib) is the first oral tyrosine kinase inhibitor approved for the treatment of tumors with NTRK gene fusion, regardless of its type and location³. NTRK gene fusions are chromosomal abnormalities that develop when an NTRK gene binds with another unrelated gene and forms mutated TRK proteins³. These TRK fusion proteins trigger uncontrolled formation and growth of cancerous cells in different parts of the body³. The active ingredient in Vitraki, larotrectinib, targets NTRK fusion genes that form mutated TRK proteins and inhibits survival of cancer cells¹⁰.

Where has Vitrakvi (larotrectinib) been approved?

Vitrakvi (larotrectinib) was approved by:  

• Food and Drug Administration (FDA), USA:
• November 26, 2018¹ with an accelerated approval for the treatment of 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 treatment⁴.

The FDA reviewed Vitrakvi (larotrectinib) under the Priority Review program, and granted it a breakthrough therapy designation and orphan drug designation⁵.

Orphan drug, breakthrough therapy, and fast track designations are processes designed to facilitate and expedite the development of a medicine to treat serious conditions and fill an unmet medical need^6,7,8.Conditionally approved, pending results of trials to verify its clinical benefit by:

• Health Canada

  • In July 2019 for the treatment of adult and paediatric patients with solid tumours 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 treatments¹⁴

Please note that this medicine may have also been approved in other regions than the ones we’ve listed. If you have a question about its approval in a specific country feel free to contact our support team.

How is Vitrakvi (larotrectinib) taken?

The standard dosage is²:

• 100 mg taken orally twice daily for patients with body surface area of at least 1.0 m²
• 100 mg/m2 for pediatric patients with body surface area less than 1.0 m².

Reduction in dose may be required based on symptoms and experienced side effects. During treatment with Vizimpro (dacomitinib), interactions with strong CYP3A4 inhibitors, strong CYP3A4 inducers, and sensitive CYP3A4 substrates should be avoided.Complete information about Vitrakvi (larotrectinib) dosage and administration can be found in the official prescribing information listed in our references section²

Note: Please consult with your treating doctor for personalised dosing, and interactions with other medicines.

Are there any known side effects or adverse reactions of Vitrakvi (larotrectinib)?

Common adverse reactionsThe most common adverse reactions listed in the prescribing information include²:

• fatigue
• nausea
• dizziness
• vomiting
• increased aspartate aminotransferase (AST, an enzyme in amino acid metabolism)
• cough
• increased alanine transaminase (ALT, an enzyme in amino acid metabolism)
• constipation
• diarrhoea.

Serious adverse reactionsThe serious adverse reactions listed in the prescribing information include²:

• pyrexia
• diarrhoea
• sepsis
• abdominal pain
• dehydration
• vomiting

Use in specific populationsVitrakvi (larotrectinib) can be fatal for a fetus, it is advised to avoid pregnancies and breastfeeding.

For a comprehensive list of side effects and adverse reactions please refer to the official prescribing information².

References

1. vitraki-us.com

Cited 24/01/2019.

2. Summary of Product Characteristics [FDA]: Vitrakvi (larotrectinib) [PDF]

Loxo Oncology Inc., cited on 24/01/2019

3. Loxo Oncology press release, FDA Approves Vitrakvi® (larotrectinib), the First Ever TRK Inhibitor, for Patients with Advanced Solid Tumors Harboring an NTRK Gene Fusion(1,2), date 26/11/2018, cited on 24/01/2019

4. FDA Press Release, FDA approves an oncology drug that targets a key genetic driver of cancer, rather than a specific type of tumor, date 26/11/2018, cited on 24/01/2019.

5. FDA Approved Drugs, FDA approves larotrectinib for solid tumors with NTRK gene fusions, last update 12/17/2018, cited on 24/01/2019. 

6. FDA Definitions: Fast Track,

www.fda.com, cited on 24/01/2019.

7. FDA Definitions: Breakthrough

www.fda.com, cited on 24/01/2019.

8. FDA Definitions: Orphan drug

www.fda.com, cited on 24/01/2019.

9. EMA Public summary of opinion on orphan designation: Vitrakvi (larotrectinib)

www.ema.com, cited on 24/01/2019.

10. National Cancer Institute Drug Dictionary: larotrectinib sulfate

www.cancer.gov, cited on 24.01.2019.

11. National Cancer Institute Dictionary of Genetics Terms: next generation sequencing

www.cancer.gov, cited on 31.01.2019.

12. Nature.com, Next-generation sequencing

www.nature.com, cited on 31.01.2019.

13. EMA Public summary of opinion on orphan designation: Vitrakvi (larotrectinib)

www.ema.com, cited on 25/07/2019.

14. Summary of Product Characteristics [Health Canada]: Vitrakvi (larotrectinib) [PDF]

Bayer, 04/07/2019.