The approval marks the second drug sanctioned to treat any type of cancer with a certain genetic feature, rather than the drug targeting a cancer that originated in a specific part of the body, the agency said in a news release. Vitrakvi targets solid tumors that have a neurotrophic receptor tyrosine kinase (NTRK) gene fusion without a known acquired resistance mutation.
The type of mutation targeted by the drug is rare, but can occur in many places in the body. The drug was evaluated in clinical studies involving 55 children and adults with a targeted form of cancer. Of the 75 percent of recipients who responded to the drug, 73 percent of responses lasted at least six months and 39 percent lasted a year or more, the FDA said.
The drug's most common side effects included fatigue, nausea, cough, constipation, diarrhea, dizziness, and vomiting. Pregnant or breastfeeding women should not take Vitrakvi, which could harm a developing fetus or newborn baby, the agency said.