On 11 December, 2015 the US Food and Drug Administration (FDA) approved uridine triacetate (Vistogard) for the emergency treatment of adults and children who receive an overdose of the cancer treatment fluorouracil or capecitabine, or who develop certain severe or life-threatening toxicities within four days of receiving these cancer treatments.
“Treating cancer requires not only selecting which drug may be most effective and well tolerated, but ensuring the correct dose is given at proper intervals. While rare, unintentional overdose can occur,” said Dr Richard Pazdur, director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research. It is a first-of-its-kind therapy that can potentially save lives following overdose or life-threatening toxicity from these chemotherapy agents.
Fluorouracil (received by infusion) and capecitabine (taken orally) are fluoropyrimidines that have been used for decades to treat several types of cancer, including breast and gastrointestinal cancers. An overdose of fluorouracil or capecitabine is rare, but when it occurs, the effects are serious and can be fatal.
Vistogard, taken orally, blocks cell damage and cell death caused by chemotherapy with fluoropyrimidines. Patients should take Vistogard as soon as possible after the overdose (whether or not they have symptoms) or early-onset (within four days) of severe or life-threatening toxicity. The patient’s health care provider will determine when he or she should return to the prescribed chemotherapy after treatment with Vistogard.
The efficacy and safety of Vistogard were studied in 135 adult and paediatric cancer patients who were treated in two separate trials and had either received an overdose of flourouracil or capecitabine, or had early-onset, unusually severe or life-threatening toxicities within 96 hours after receiving flourouracil (not due to an overdose).
The studies’ primary measure was survival at 30 days or until chemotherapy could resume if prior to 30 days. Of those who were treated with Vistogard for overdose, 97% were still alive at 30 days. Of those treated with Vistogard for early-onset severe or life-threatening toxicity, 89% were alive at 30 days. In both studies, 33% of patients resumed chemotherapy in less than 30 days.
Vistogard is not recommended for treating non-emergency adverse reactions associated with flourouracil or capecitabine because Vistogard may lessen the efficacy of these drugs. The safety and efficacy of Vistogard initiated more than 96 hours following the end of treatment with flourouracil or capecitabine have not been established.
The most common side effects of treatment with Vistogard were diarrhoea, vomiting and nausea.
The FDA granted Vistogard orphan drug designation, which provides financial incentives, like clinical trial tax credits, user fee waivers, and eligibility for market exclusivity to promote rare disease drug development. Vistogard was also granted priority review and fast track designations, which are distinct programmes intended to facilitate and expedite the development and review of certain new drugs in light of their potential to benefit patients with serious or life-threatening conditions.
Vistogard is marketed by Wellstat Therapeutics Corporation based in Gaithersburg, Maryland.