Administration of Lonsurf (Trifluridine/Tipiracil) for Gastric Cancer
Lonsurf (trifluridine/tipiracil) is administered orally at a dose of 35 mg/m² twice daily on days 1-5 and days 8-12 of each 28-day cycle for patients with previously treated recurrent or metastatic gastric cancer. 1, 2
Dosing Details
- Standard dose: 35 mg/m² twice daily (maximum 80mg per single dose)
- Administration schedule: Days 1-5 and days 8-12 of each 28-day cycle
- Route: Oral tablets taken within 1 hour after morning and evening meals
- Formulation: Combination of 15mg and 20mg tablets to achieve the appropriate dose
Patient Selection
Lonsurf is FDA-approved as a third-line or subsequent treatment option for patients with:
- Previously treated recurrent or metastatic gastric or gastroesophageal junction adenocarcinoma
- Disease progression after at least two prior lines of therapy
The NCCN guidelines recommend Lonsurf as a preferred category 1 treatment option for patients with recurrent or metastatic gastric cancer in the third-line or subsequent setting 1.
Efficacy Considerations
- The global phase III TAGS trial demonstrated improved overall survival with Lonsurf plus best supportive care (5.7 months) compared to placebo plus best supportive care (3.6 months) 1, 3
- Progression-free survival was also significantly longer in the Lonsurf group (2.0 vs 1.7 months) 1
- Benefits were observed regardless of previous gastrectomy status 1
Important Monitoring and Toxicity Management
Common Grade 3-4 Toxicities
- Hematologic: Neutropenia (38%), leukopenia (21%), anemia (19%), lymphocytopenia (19%) 1, 2
- Gastrointestinal: Nausea, decreased appetite, diarrhea, vomiting, abdominal pain 2
Special Considerations
- Patients aged ≥65 years have a higher incidence of moderate renal impairment (31% vs 17% in the overall population) 1
- Regular complete blood count monitoring is essential before and during treatment
- Dose modifications may be required based on hematologic parameters and tolerability
Combination Therapy Options
Lonsurf can be administered in combination with bevacizumab using:
- Standard schedule: Lonsurf as above plus bevacizumab 5 mg/kg IV on day 1 of each 28-day cycle 2
- Alternative combination: Lonsurf plus ramucirumab has shown acceptable safety profile and clinical activity in previously treated advanced gastric cancer 4
Clinical Pearls
- Lonsurf did not result in any partial or complete responses in the pivotal TAGS trial but did improve survival 1
- Best suited for patients with low-volume gastric cancer who have minimal or no symptoms and can swallow pills 1
- The efficacy of Lonsurf must be balanced against its toxicity profile, particularly hematologic adverse events
- Treatment should be continued until disease progression or unacceptable toxicity
Remember that while Lonsurf provides a valuable treatment option for heavily pretreated patients with gastric cancer, careful patient selection is crucial given its toxicity profile and modest survival benefit.