Prespecified candidate biomarkers identify follicular lymphoma patients who achieved longer progression-free survival with bortezomib-rituximab versus rituximab.

PURPOSE: Identify subgroups of patients with relapsed/refractory follicular lymphoma deriving substantial progression-free survival (PFS) benefit with bortezomib-rituximab versus rituximab in the phase III LYM-3001 study. EXPERIMENTAL DESIGN: A total of 676 patients were randomized to five 5-week cycles of bortezomib-rituximab or rituximab. The primary end point was PFS; this prespecified analysis of candidate protein biomarkers and genes was an exploratory objective. Archived tumor tissue and whole blood samples were collected at baseline. Immunohistochemistry and genetic analyses were completed for 4 proteins and 8 genes. RESULTS: In initial pairwise analyses, using individual single-nucleotide polymorphism genotypes, one biomarker pair (PSMB1 P11A C/G heterozygote, low CD68 expression) was associated with a significant PFS benefit with bortezomib-rituximab versus rituximab, controlling for multiple comparison corrections. The pair was analyzed under dominant, recessive, and additive genetic models, with significant association with PFS seen under the dominant model (G/G+C/G). In patients carrying this biomarker pair [PSMB1 P11A G allele, low CD68 expression (≤50 CD68-positive cells), population frequency: 43.6%], median PFS was 14.2 months with bortezomib-rituximab versus 9.1 months with rituximab (HR 0.47, P < 0.0001), and there was a significant overall survival benefit (HR 0.49, P = 0.0461). Response rates were higher and time to next antilymphoma therapy was longer in the bortezomib-rituximab group. In biomarker-negative patients, no significant efficacy differences were seen between treatment groups. Similar proportions of patients had high-risk features in the biomarker-positive and biomarker-negative subsets. CONCLUSIONS: Patients with PSMB1 P11A (G allele) and low CD68 expression seemed to have significantly longer PFS and greater clinical benefit with bortezomib-rituximab versus rituximab.

Bortezomib plus rituximab versus rituximab alone in patients with relapsed, rituximab-naive or rituximab-sensitive, follicular lymphoma: a randomised phase 3 trial.

BACKGROUND: Bortezomib and rituximab have shown additive activity in preclinical models of lymphoma, and have been shown to be active and generally well tolerated in a randomised phase 2 study in patients with follicular and marginal zone lymphoma. We compared the efficacy and safety of rituximab alone or combined with bortezomib in patients with relapsed or refractory follicular lymphoma in a phase 3 setting. METHODS: In this multicentre phase 3 trial, rituximab-naive or rituximab-sensitive patients aged 18 years or older with relapsed grade 1 or 2 follicular lymphoma were randomly assigned (1:1) to receive five 35-day cycles consisting of intravenous infusions of rituximab 375 mg/m(2) on days 1, 8, 15, and 22 of cycle 1, and on day 1 of cycles 2-5, either alone or with bortezomib 1·6 mg/m(2), administered by intravenous injection on days 1, 8, 15, and 22 of all cycles. Randomisation was stratified by FLIPI score, previous use of rituximab, time since last therapy, and region. Treatment assignment was based on a computer-generated randomisation schedule prepared by the sponsor. Patients and treating physicians were not masked to treatment allocation. The primary endpoint was progression-free survival analysed by intention to treat. This trial has been completed and is registered with ClinicalTrials.gov, number NCT00312845. FINDINGS: Between April 10, 2006, and Aug 12, 2008, 676 patients were randomised to receive rituximab (n=340) or bortezomib plus rituximab (n=336). After a median follow-up of 33·9 months (IQR 26·4-39·7), median progression-free survival was 11·0 months (95% CI 9·1-12·0) in the rituximab group and 12·8 months (11·5-15·0) in the bortezomib plus rituximab group (hazard ratio 0·82, 95% CI 0·68-0·99; p=0·039). The magnitude of clinical benefit was not as large as the anticipated prespecified improvement of 33% in progression-free survival. Patients in both groups received a median of five treatment cycles (range 1-5); 245 of 339 (72%) and 237 of 334 (71%) patients in the rituximab and bortezomib plus rituximab groups, respectively, completed five cycles. Of patients who did not complete five cycles, most discontinued early because of disease progression (77 [23%] patients in the rituximab group, and 56 [17%] patients in the bortezomib plus rituximab group). Rates of adverse events of grade 3 or higher (70 [21%] of 339 rituximab-treated patients vs 152 [46%] of 334 bortezomib plus rituximab treated patients), and serious adverse events (37 [11%] patients vs 59 [18%] patients) were lower in the rituximab group than in the combination group. The most common adverse events of grade 3 or higher were neutropenia (15 [4%] patients in the rituximab group and 37 [11%] patients in the bortezomib plus rituximab group), infection (15 [4%] patients and 36 [11%] patients, respectively), diarrhoea (no patients and 25 [7%] patients, respectively), herpes zoster (one [<1%] patient and 12 [4%] patients, respectively), nausea or vomiting (two [<1%] patients and 10 [3%] patients, respectively) and thrombocytopenia (two [<1%] patients and 10 [3%] patients, respectively). No individual serious adverse event was reported by more than three patients in the rituximab group; in the bortezomib plus rituximab group, only pneumonia (seven patients [2%]) and pyrexia (six patients [2%]) were reported in more than five patients. In the bortezomib plus rituximab group 57 (17%) of 334 patients had peripheral neuropathy (including sensory, motor, and sensorimotor neuropathy), including nine (3%) with grade 3 or higher, compared with three (1%) of 339 patients in the rituximab group (no events of grade ≥3). No patients in the rituximab group but three (1%) patients in the bortezomib plus rituximab group died of adverse events considered at least possibly related to treatment. INTERPRETATION: Although a regimen of bortezomib plus rituximab is feasible, the improvement in progression-free survival provided by this regimen versus rituximab alone was not as great as expected. The regimen might represent a useful addition to the armamentarium, particularly for some subgroups of patients. FUNDING: Johnson & Johnson Pharmaceutical Research & Development and Millennium Pharmaceuticals, Inc.