Prognostic and predictive value of circulating tumor cells and CXCR4 expression as biomarkers for a CXCR4 peptide antagonist in combination with carboplatin-etoposide in small cell lung cancer: exploratory analysis of a phase II study.

Background Circulating tumor cells (CTCs) and chemokine (C-X-C motif) receptor 4 (CXCR4) expression in CTCs and tumor tissue were evaluated as prognostic or predictive markers of CXCR4 peptide antagonist LY2510924 plus carboplatin-etoposide (CE) versus CE in extensive-stage disease small cell lung cancer (ED-SCLC). Methods This exploratory analysis of a phase II study evaluated CXCR4 expression in baseline tumor tissue and peripheral blood CTCs and in post-treatment CTCs. Optimum cutoff values were determined for CTC counts and CXCR4 expression in tumors and CTCs as predictors of survival outcome. Kaplan-Meier estimates and hazard ratios were used to determine biomarker prognostic and predictive values. Results There was weak positive correlation at baseline between CXCR4 expression in tumor tissue and CTCs. Optimum cutoff values were H-score ≥ 210 for CXCR4+ tumor, ≥7% CTCs with CXCR4 expression (CXCR4+ CTCs), and ≥6 CTCs/7.5 mL blood. Baseline H-score for CXCR4+ tumor was not prognostic of progression-free survival (PFS) or overall survival (OS). Baseline CXCR4+ CTCs ≥7% was prognostic of shorter PFS. CTCs ≥6 at baseline and cycle 2, day 1 were prognostic of shorter PFS and OS. None of the biomarkers at their respective optimum cutoffs was predictive of treatment response of LY2510924 plus CE versus CE. Conclusions In patients with ED-SCLC, baseline CXCR4 expression in tumor tissue was not prognostic of survival or predictive of LY2510924 treatment response. Baseline CXCR4+ CTCs ≥7% was prognostic of shorter PFS. CTC count ≥6 at baseline and after 1 cycle of treatment were prognostic of shorter PFS and OS.

A randomized phase II study of LY2510924 and carboplatin/etoposide versus carboplatin/etoposide in extensive-disease small cell lung cancer.

OBJECTIVES: This multicenter, open-label, randomized phase II study evaluated the efficacy and safety of LY2510924 (LY) added to first-line standard of care (SOC) chemotherapy for extensive-disease small cell lung cancer (ED-SCLC) and explored the predictive value of C-X-C motif receptor 4 (CXCR4) tumor response. MATERIALS AND METHODS: Patients with treatment-naïve ED-SCLC were randomized (1:1) to receive up to six 21-day cycles of carboplatin/etoposide alone (SOC) or in combination with 20mg LY2510924 administered subcutaneously on days 1-7 of each cycle (LY+SOC). The primary efficacy endpoint was progression-free survival (PFS). Secondary endpoints were overall survival (OS), overall response rate (ORR), and safety. Response relative to CXCR4 expression on baseline tumor was an exploratory endpoint. RESULTS: Of 94 patients randomized, 90 received treatment (LY+SOC, n=47; SOC, n=43). Median PFS (95% confidence interval [CI]) was 5.88 (4.83, 6.24) months for LY+SOC versus 5.85 (4.63, 5.51) months for SOC (hazard ratio [95% CI], 1.01 [0.62, 1.63]; p=0.9806). Median OS (95% CI) was 9.72 (6.64, 11.70) months for LY+SOC versus 11.14 (8.25, 13.44) months for SOC. ORR was 74.5% for LY+SOC versus 81% for SOC. Safety results between arms were similar, although the following adverse events were more frequent on the LY+SOC arm: anemia (61.7% vs 46.5%), neutropenia (61.7% vs 53.5%), leukopenia (27.7% vs 9.3%), vomiting (27.7% vs 16.3%), and pneumonia (10.6% vs 2.3%). In patients whose baseline CXCR4 expression was above the optimal cutoff (H-score 210), the hazard ratio (95% CI) was 1.27 (0.51, 3.15). CONCLUSION: LY2510924 did not improve efficacy but had an acceptable toxicity profile when added to SOC for ED-SCLC.

A Randomized, Open-Label Phase 2 Study of the CXCR4 Inhibitor LY2510924 in Combination with Sunitinib Versus Sunitinib Alone in Patients with Metastatic Renal Cell Carcinoma (RCC).

PURPOSE: The chemokine (C-X-C Motif) receptor 4 (CXCR4) and its ligand, stromal-cell derived factor-1 (SDF-1), are frequently overexpressed in a variety of solid tumors, and are believed to play important roles in the regulation of organ-specific metastasis, tumor growth, invasion, and survival. In this randomized Phase 2 trial, we evaluated the safety and efficacy of LY2510924 (LY), a peptide antagonist of CXCR4, combined with sunitinib (SUN) in the first-line treatment of advanced renal cell carcinoma (RCC). PATIENTS AND METHODS: Eligible patients were randomized (2:1) to receive LY (20 mg SC daily) + SUN (50 mg PO daily for 4 weeks followed by 2 weeks off) or SUN alone. Response was assessed after two cycles; patients continued treatment until tumor progression or intolerable toxicity. The study was powered to detect a 47 % increase in median progression-free survival (PFS). RESULTS: One hundred eight patients were randomized and treated (LY + SUN, 72; SUN, 36); median duration of treatment of five cycles. Observed median PFS was 8.1 months with LY + SUN and 12.3 months with SUN; Bayesian time-to-event HR 1.23; 95 % credible interval: 0.74, 1.96. LY was well tolerated; the toxicity profile was typical of SUN. No efficacy differences were seen between treatments groups when subsets with high versus low levels of CXCR4 tumor expression were compared. CONCLUSIONS: The addition of LY to SUN in the first-line treatment of metastatic RCC was well tolerated, but did not improve the PFS or overall survival (OS) vs. SUN alone. CXCR4 remains an unproven therapeutic target for the treatment of RCC. GOV IDENTIFIER: NCT01391130.

A phase I trial of LY2510924, a CXCR4 peptide antagonist, in patients with advanced cancer.

PURPOSE: Overexpression of C-X-C motif receptor 4 (CXCR4) is implicated in tumor progression. LY2510924 is a peptide antagonist, which blocks stromal cell-derived factor-1 (SDF1) from CXCR4 binding. EXPERIMENTAL DESIGN: This phase I study included two parts: a 3+3 dose escalation (part A) and dose confirmation (part B). LY2510924 was administered as a daily subcutaneous injection on a 28-day cycle. The primary objective was to determine the recommended phase II dose. Secondary objectives included safety, pharmacokinetics, efficacy, and pharmacodynamic response, including mobilization of CD34(+) hematopoietic stem cells into the peripheral blood. RESULTS: Forty-five patients were enrolled, 25 in part A and 20 in part B. Patients were administered increasing doses of LY2510924: 1.0, 2.5, 5.0, 10, 20, and 30 mg/day for part A and 2.5 or 20 mg/day for part B. Two patients (30-mg/day cohort) experienced dose-limiting toxicities of grade 3 increased neutrophil count. The maximum tolerated dose (MTD) was 20 mg/day. The most common drug-related treatment-emergent adverse events were fatigue (9%), injection-site reaction (9%), injection site pruritus (7%), and nausea (7%). The best response was stable disease for nine patients (20%). At the end of cycle 1, mean peak LY2510924 plasma concentration and the 24-hour area under the plasma concentration versus time curve increased slightly more than dose proportionally. LY2510924 dose dependently increased CD34(+) cell counts in peripheral blood up to 18-fold. CONCLUSIONS: LY2510924 demonstrated CD34(+) cell mobilization at doses ≥2.5 mg/day with a tolerable safety profile up to an MTD of 20 mg/day.

A multicenter, open-label, noncomparative screening study of enzastaurin in adult patients with non-Hodgkin lymphomas.

PURPOSE: To assess the antitumor activity of enzastaurin in patients with non-Hodgkin lymphomas: T-cell lymphoma (n = 23): cutaneous and peripheral T-cell lymphoma; indolent B-cell lymphomas (n = 19): small lymphocytic, follicular grade 1 or 2, marginal zone lymphomas; and aggressive B-cell lymphomas (n = 15): follicular lymphomas grade 3, aggressive lymphoma with a clinical history. The primary objective was to determine overall tumor response. Secondary objectives included duration of response and safety. MATERIALS AND METHODS: In this multicenter, open-label, noncomparative, screening study conducted between December 2007 and February 2009, patients (≥ 18 years) who relapsed after ≥ 1 prior systemic treatment or who were intolerant to standard systemic therapy received 250 mg oral enzastaurin (125 mg tablets twice a day; a 1125-mg loading dose on day 1), in 28-day cycles for up to 2 years unless unacceptable toxicity or progressive disease occurred. RESULTS: Responses were seen in follicular lymphomas grade 3 (1/5, 20.0%), cutaneous T-cell lymphoma (2/11, 18.2%), small lymphocytic lymphomas (1/7, 14.3%), and aggressive lymphoma with a clinical history (1/10, 10.0%) in this heavily pretreated patient population (median prior therapies range from 4 to 10). Most drug-related toxicities were grade 1/2, the most common being diarrhea, peripheral edema, and pruritus. CONCLUSIONS: Enzastaurin was well tolerated but demonstrated modest responses across subgroups in this heavily pretreated patient population.