Conley, Christoher R

8053 Background: Lenalidomide (LEN) is an immunomodulatory agent that has shown significant single-agent anti-lymphoma activity in patients with relapsed disease and in combination may enhance the efficacy of rituximab by various mechanisms. There is limited data on the role of LEN in combination regimens for treatment-naïve patients. This phase II single arm trial was designed to evaluate tumor response, toxicity (AE) and survival with a combination of LEN, rituximab, cyclophosphamide (CTX) and dexamethasone (DEX) (LR-CD) in symptomatic untreated patients with low grade B-cell non-Hodgkin lymphoma. Methods: Eligibility required age ≥18, ECOG PS ≤2, confirmed diagnosis of low-grade B-cell lymphoma (FL1-2, SLL, MZL or LPL/WM), measurable nodes ≥2cm or IgM ≥400mg/dL(LPL/WM), ANC ≥1400/mm3, platelets ≥100,000/mm3, creatinine ≤2mg/dL, signed informed consent and in need of therapy. Treatment consisted of IV rituximab 375mg/m2 D1, oral LEN 20mg D1-21, CTX 250mg/m2 D1, 8, 15, DEX 40mg D1, 8, 15, 22 and ASA 325 mg daily in a 28 day cycle. Treatment continued 2 cycles beyond best response (max 12). Toxicity was assessed by NCI CTCAE v3.0. Results: 28 patients have enrolled at Mayo Clinic with 25 evaluable for toxicity and 21 for response: Median age 65(43-83), 72% male, FL 24%, MZL 28%, LPL/WM 38%, and SLL 4%. Median number of cycles given was 5. Overall response in 21 patients with response data is 95% (95% CI 76-100%) with 19% CR (95% CI 5-42%), and 76% PR (confirmed and unconfirmed, 95% CI 53-92%). The ORR in 8 patients with LPL/WM with response data was 88%, all PR (95% CI 47-100%). At a median f/u of 14.7 months 96% are alive without progression. 1 death (unrelated) occurred 7.7 months after completing 12 cycles of treatment. The most common grade ≥3 AEs were neutropenia (37.5%), leukopenia (16.7%), anemia (12.5%) and fatigue (12.5%). Conclusions: The combination LR-CD with the novel agent LEN is feasible, well tolerated and produces high response rates in symptomatic patients with low grade B-cell NHL. Toxicities are manageable and similar to reported data of single agent LEN.