The U.S. Food and Drug Administration (FDA) approved Vitrakvi® (larotrectinib), the first ever oral TRK inhibitor, 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 (ORR) and duration of response (DOR). Continued approval for this indication may be contingent upon verification and description of clinical benefit in confirmatory trials. Vitrakvi is the first treatment to receive a tumor-agnostic indication at the time of initial FDA approval. In clinical trials of patients with TRK fusion cancer, Vitrakvi demonstrated an ORR of 75 percent (N=55) (95% CI, 61%, 85%), including a 22 percent complete response (CR) rate.
“The FDA approval of larotrectinib marks an important milestone in how we treat cancers that have an NTRK gene fusion – a rare driver of cancer. I have seen firsthand how treatment with larotrectinib, which is designed specifically for this oncogenic driver, can deliver clinically meaningful responses in patients with TRK fusion cancer, regardless of patient age or tumor type,” said David Hyman, M.D., chief of the Early Drug Development Service at Memorial Sloan Kettering Cancer Center and a global principal investigator for a larotrectinib clinical trial. “We now have the first therapy approved for this genomic alteration, regardless of cancer type.”
NTRK gene fusions are genomic alterations that result in constitutively-activated chimeric TRK fusion proteins that can act as an oncogenic driver, promoting cell proliferation and survival in tumor cell lines. Vitrakvi, developed by Bayer and Loxo Oncology, Inc., is a CNS active TRK inhibitor designed to inhibit these proteins. TRK fusions can be found in many types of solid tumors and affect both children and adults. In the clinical trials that were the basis for this approval, Vitrakvi showed clinical benefit across numerous unique tumor types, including lung, thyroid, melanoma, GIST, colon, soft tissue sarcoma, salivary gland and infantile fibrosarcoma.
“Today’s approval of Vitrakvi is the culmination of years of hard work and research by many people to bring the first ever treatment to patients with TRK fusion cancer. TRK fusions are rare, but occur across many different tumor types. In this era of precision medicine, we are delivering on Bayer’s commitment to advance the future of cancer care while providing value for patients and physicians,” said Robert LaCaze, member of the executive committee of Bayer’s Pharmaceuticals Division and head of the Oncology Strategic Business Unit at Bayer. “It is very rewarding to provide a therapy specifically for patients with advanced solid tumors harboring an NTRK gene fusion.”
Vitrakvi® (larotrectinib) has warnings and precautions of neurotoxicity, hepatotoxicity and embryo-fetal toxicity.The most common adverse events observed in more than 20 percent of patients, regardless of attribution, were increased ALT, increased AST, anemia, fatigue, nausea, dizziness, cough, vomiting, constipation, and diarrhea. The majority of adverse events occurring in greater than or equal to 10 percent of patients were grade 1 or 2.
TRK fusion cancer occurs across a broad range of tumor types with varying frequency in both adult and pediatric patients. It is diagnosed through the identification of NTRK gene fusions using specific tests, including those that employ next-generation sequencing (NGS) and fluorescence in situ hybridization (FISH).2 Patients eligible for treatment with Vitrakvi should be selected based on the presence of an NTRK gene fusion in their tumor.
“We are grateful to the investigators, research teams and patients who contributed to and participated in the larotrectinib clinical trials that supported this approval,” said Josh Bilenker, M.D., chief executive officer of Loxo Oncology. “The approval of Vitrakvi is a testament to the relentless prioritization of biology in the drug development process. It is now even more critical to screen patients of all ages with advanced solid tumors for actionable genomic insights that could benefit their care or aid in their referral to clinical trials.”
The FDA reviewed Vitrakvi under Priority Review, which is reserved for medicines that could provide significant improvements in the safety or effectiveness of the treatment for serious conditions. The FDA previously granted Vitrakvi Breakthrough Therapy Designation, Rare Pediatric Disease Designation and Orphan Drug Designation.
“We welcome the FDA approval of Vitrakvi and the innovations in genomic testing that make such precision medicine a reality,” said Andrea Stern Ferris, president and chief executive officer of the LUNGevity Foundation. “We’re seeing scientific advancements, like genomic testing capable of detecting an NTRK gene fusion, beginning to transform the treatment of cancer and provide new options for patients.”
Vitrakvi will be available in oral capsules as well as a liquid formulation for adults and children.
For more information, visit www.vitrakvi.com