- FDA has granted accelerated approval for larotrectinib (Vitrakvi), to treat solid tumors that have a targeted biomarker — neurotrophic receptor tyrosine kinase (NTRK) gene fusion — without a known acquired resistance mutation.
- Larotrectinib capsules and oral solution are indicated for:
- Patients with metastatic disease, or where surgical resection is likely to yield severe morbidity, and
- have no satisfactory alternatives or that have progressed following treatment.
Why this matters
- First “site agnostic” therapy specifically developed to target a common biomarker.
- See also: FDA greenlights first cancer treatment for any solid tumor sharing a specific biomarker
Clinical study designs
- 3 single-arm, open-label clinical trials involving 55 adult and pediatric patients (median age, 45 years; range, 4 months to 76 years).
- Salivary gland tumors (22%), soft tissue sarcoma (20%), infantile fibrosarcoma (13%), and thyroid cancer (9%) were most common.
- Funding: Bayer.
- Objective response rate, 75% (95% CI, 61%-85%).
- Complete response rate, 22%.
- Duration of response (DOR): ≥6 months, 73%; ≥9 months, 63%; ≥12 months, 39%.
- Median DOR (range, 1.6+, 33.2+) and PFS had not been reached at time of analysis.
- Common adverse reactions (≥20%) were fatigue, nausea, dizziness, vomiting, increased liver enzymes, constipation, and diarrhea.
- Labeling carries warnings regarding risks for neurotoxicity, hepatotoxicity, and embryo-fetal toxicity.
Prescribing Information, click here.