Background
Phase III, open-label, randomized controlled trial. 379 patients with advanced-stage (III–IV), asymptomatic, non-bulky follicular lymphoma (FL) not meeting GELF criteria for treatment (low tumor burden). Tested whether early rituximab monotherapy improves outcomes over the traditional watchful-waiting standard of care.
Interventions and follow up
Arm A: Early rituximab 375 mg/m² IV weekly × 4 induction; responding/stable patients then to maintenance (375 mg/m² every 2 months × 12) or no further treatment
Arm B: Watchful waiting, no treatment until GELF criteria met or patient preference
Primary endpoint: Time to next lymphoma treatment
Median follow-up: ~10 years (long-term update)
Arm B: Watchful waiting, no treatment until GELF criteria met or patient preference
Primary endpoint: Time to next lymphoma treatment
Median follow-up: ~10 years (long-term update)
Results
Time to next treatment: median 10.0 vs 2.8 years, HR 0.35, 95% CI 0.22–0.56, P<.0001
10-year PFS: 47% (rituximab) vs 18% (watchful waiting)
10-year OS: 82% vs 80%, not significantly different
Transformation rate: similar between arms
10-year PFS: 47% (rituximab) vs 18% (watchful waiting)
10-year OS: 82% vs 80%, not significantly different
Transformation rate: similar between arms
Adverse events
Infusion-related: Grade ≥3 infusion reactions 2–3% in the early rituximab arm
Infectious/other: Infections similar between arms; no excess secondary malignancies; rituximab well tolerated with minimal long-term toxicity
Infectious/other: Infections similar between arms; no excess secondary malignancies; rituximab well tolerated with minimal long-term toxicity
Conclusions
Early rituximab significantly delayed time to next treatment and improved PFS in low-tumor-burden FL but did not improve OS. Results support early rituximab as an alternative to watchful waiting in asymptomatic low-burden FL, though watchful waiting remains acceptable given no survival benefit.
Key Limitations
No OS benefit despite prolonged PFS, raising the question of whether earlier treatment alters natural history or merely delays inevitable subsequent therapy. The maintenance arm was introduced partway through, creating heterogeneity. No crossover data; quality-of-life and patient-preference data were inadequately captured.
Clinical Context
This trial shifted practice at some centers to offer early rituximab as an alternative for low-burden FL patients preferring active treatment. ESMO retains watchful waiting as a standard option, with early rituximab as an acceptable alternative. The RESORT trial separately found similar OS for maintenance vs retreatment rituximab; neither approach has supplanted watchful waiting given the absence of an OS advantage.