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Purpose: Preclinical evidence indicates that the bone marrow microenvironment provides a protective niche for leukemic stem cells, allowing them to evade the effects of BCR-ABL tyrosine kinase inhibitors (TKIs), but that targeting of the JAK-STAT pathway with the JAK2 inhibitor ruxolitinib increases TKI-induced apoptosis. A phase I clinical trial (NCT01702064) investigated the tolerability and safety of treating chronic-phase chronic myeloid leukemia patients with ruxolitinib in combination with the BCR-ABL TKI nilotinib and explored initial efficacy evidence., Experimental Design: Eleven patients already treated with single-agent nilotinib (300-400 mg twice daily) commenced combination therapy, and molecular responses were evaluated after 6 months. Three ruxolitinib dose cohorts were studied: 5 mg, 10 mg, and 15 mg twice daily., Results: One patient experienced a grade 3/4 adverse event (hypophosphatemia) and 36% of patients experienced grade 1/2 anemia. Of 10 patients who were evaluable for responses, 40% had undetectable BCR-ABL transcripts, as measured by quantitative RT-PCR after 6 months. Plasma inhibitory assay results revealed a decrease in phospho-STAT3 levels after treatment with ruxolitinib. The recommended phase 2 dose of ruxolitinib was 15 mg BID., Conclusions: Overall, this combination was safe and well-tolerated, and the molecular responses were encouraging, thereby warranting further investigation in a phase 2 trial., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Chronic lymphocytic leukemia (CLL) is an incurable disease in need of new therapeutic strategies. The immunomodulatory agent, lenalidomide, has shown activity as salvage therapy for CLL. In this phase II trial, we combined lenalidomide with rituximab in 25 patients (range, 41-79) with refractory/relapsed CLL. Lenalidomide was administered orally on escalating doses, with cycle 1 doses of 2.5mg daily on days 1-7, 5mg on days 8-14, and 10mg on days 15-21 followed by 7days off. On cycle 2 and beyond, lenalidomide was administered at 20mg daily on days 1-21. Rituximab was administered at 375mg/m(2) intravenously on a weekly basis for the first cycle starting on day 15 for 4 doses, with each cycle being 28days. Treatment was continued until disease progression or toxicity. Overall response rate was 45.8% on intent-to-treat and 61.1% in evaluable patients (all partial responses). Median time to treatment failure was 14.3 months for evaluable patients, and median overall survival was not reached. The most common grade 3/4 toxicity was neutropenia (72% of patients). The most common nonhematologic toxicity was infection (29% of patients). Lenalidomide combined with rituximab showed activity in heavily treated refractory CLL with an acceptable toxicity profile., (Copyright © 2016 Elsevier Ltd. All rights reserved.)