Quick Facts About: Trifluridine and Tipiracil

Lonsurf, FTD–TPI

Yes, in 2015.

Trifluridine and tipiracil (hereafter Lonsurf) is used in metastatic colorectal cancer treatment.

It is also used to treat metastatic gastric adenocarcinoma.

*All dosages indicated here are specific to colorectal cancer treatment.

Lonsurf is a fixed-dose combination medication that is administered orally in tablet form.

Lonsurf may be used as monotherapy or in combination with bevacizumab. This is for patients who have previously received treatment using fluoropyrimidine-, oxaliplatin- and irinotecan-based chemotherapy, an anti-VEGF biological therapy, and if RAS wild-type, an anti-EGFR therapy.

Dosage is dependent on drug combination in the treatment regimen and is based on the patient’s body surface area (milligram per square meter, mg/m²).

Lonsurf is administered in 35 mg/m² per dose twice daily with food on days 1 through 5 and Days 8 through 12 of each 28-day cycle.

The tablets come in the following dosage strengths:

• 15 mg trifluridine / 6.14 mg tipiracil
• 20 mg trifluridine / 8.19 mg tipiracil

Special precaution is required for patients with

• Severe bone marrow suppression
• Ongoing pregnancy or plans to conceive

Common side effects of Lonsurf include:

• Black, tarry stools
• Bleeding gums
• Blood in the urine or stools
• Blurred vision
• Chills
• Coughing up blood
• Dizziness
• Fever
• Headache
• Hoarseness
• Increased menstrual flow or vaginal bleeding
• Lower back or side pain
• Nosebleeds
• Painful or difficult urination
• Pale skin
• Paralysis
• Pinpoint red spots on the skin
• Pounding in the ears
• Prolonged bleeding from cuts
• Red or dark brown urine
• Slow or fast heartbeat
• Sore throat
• Trouble breathing
• Ulcers, sores, or white spots in the mouth
• Unusual bleeding or bruising
• Unusual tiredness or weakness

Other less common side effects are:

• Bladder pain
• Bloody or cloudy urine
• Frequent urge to urinate
• Muscle aches
• Stuffy or runny nose

Lonsurf is a chemotherapy drug.

The combination of trifluridine and tipiracil works by inhibiting the proliferation of cancer cells. Trifluridine is a nucleoside analogue that is incorporated into the DNA of cancer cells during replication, leading to the termination of DNA synthesis and cell death. Trifluridine is selectively toxic to cancer cells because it is activated in the tumor microenvironment. This selectivity allows for greater efficacy with fewer side effects.

Tipiracil, on the other hand, enhances the bioavailability of trifluridine by inhibiting the activity of thymidine phosphorylase, an enzyme that degrades trifluridine. The inhibition of thymidine phosphorylase results in higher concentrations of trifluridine within the tumor, which enhances the therapeutic effect of trifluridine.