Voxtalisib (XL765) in patients with relapsed or refractory non-Hodgkin lymphoma or chronic lymphocytic leukaemia: an open-label, phase 2 trial.

BACKGROUND: Patients with relapsed or refractory lymphoma or chronic lymphocytic leukaemia have a poor prognosis. Therapies targeting more than one isoform of PI3K, as well as mTOR, might increase antitumour activity. We aimed to investigate the efficacy and safety of voxtalisib (also known as XL765 or SAR245409), a pan-PI3K/mTOR inhibitor, in patients with relapsed or refractory lymphoma, or chronic lymphocytic leukaemia/small lymphocytic lymphoma. METHODS: We did a non-randomised, open-label, phase 2 trial at 30 oncology clinics in the USA, Belgium, Germany, France, the Netherlands, and Australia. Patients aged 18 years or older with Eastern Cooperative Oncology Group (EGOG) performance status score of 2 or lower and relapsed or refractory mantle cell lymphoma, follicular lymphoma, diffuse large B-cell lymphoma, or chronic lymphocytic leukaemia/small lymphocytic lymphoma were enrolled and treated with voxtalisib 50 mg orally twice daily in 28-day continuous dosing cycles until progression or unacceptable toxicity. The primary endpoint was the proportion of patients in each disease-specific cohort who achieved an overall response, defined as a complete response or partial response. All patients who received more than 4 weeks of treatment and who completed a baseline and at least one post-baseline tumour assessment were analysed for efficacy and all patients were analysed for safety. This study is registered with ClinicalTrials.gov, number NCT01403636, and has been completed. FINDINGS: Between Oct 19, 2011, and July 24, 2013, 167 patients were enrolled (42 with mantle cell lymphoma, 47 with follicular lymphoma, 42 with diffuse large B-cell lymphoma, and 36 with chronic lymphocytic leukaemia/small lymphocytic lymphoma. The median number of previous anticancer regimens was three (IQR 2-4) for patients with lymphoma and four (2-5) for patients with chronic lymphocytic leukaemia/small lymphocytic lymphoma. Of 164 patients evaluable for efficacy, 30 (18·3%) achieved an overall response (partial, n=22; complete, n=8); 19 (41·3%) of 46 with follicular lymphoma, five (11·9%) of 42 with mantle cell lymphoma, two (4·9%) of 41 with diffuse large B-cell lymphoma, and four (11·4%) of 35 with chronic lymphocytic leukaemia/small lymphocytic lymphoma. The safety profile was consistent with that of previous studies of voxtalisib. The most frequently reported adverse events were diarrhoea (in 59 [35%] of 167 patients), fatigue (in 53 [32%]), nausea (in 45 [27%]), pyrexia (in 44 [26%,]), cough (in 40 [24%]), and decreased appetite (in 35 [21%]). The most frequently reported grade 3 or worse adverse events were anaemia (in 20 [12%] of 167 patients), pneumonia (in 14 [8%]), and thrombocytopenia (in 13 [8%]). Serious adverse events occurred in 97 (58·1%) of 167 patients. INTERPRETATION: Voxtalisib 50 mg given orally twice daily had an acceptable safety profile, with promising efficacy in patients with follicular lymphoma but limited efficacy in patients with mantle cell lymphoma, diffuse large B-cell lymphoma, or chronic lymphocytic leukaemia/small lymphocytic lymphoma. FUNDING: Sanofi.

Phase I dose-escalation study of the PI3K/mTOR inhibitor voxtalisib (SAR245409, XL765) plus temozolomide with or without radiotherapy in patients with high-grade glioma.

BACKGROUND: This phase I study aimed to evaluate safety, maximum tolerated dose, pharmacokinetics, pharmacodynamics, and preliminary efficacy of voxtalisib (SAR245409, XL765), a pan-class I phosphoinositide 3-kinase (PI3K) and mammalian target of rapamycin (mTOR) inhibitor, in combination with temozolomide (TMZ), with or without radiation therapy (RT), in patients with high-grade glioma. METHODS: Patients received voxtalisib 30-90 mg once daily (q.d.) or 20-50 mg twice daily (b.i.d.), in combination with 200 mg/m(2) TMZ (n = 49), or voxtalisib 20 mg q.d. with 75 mg/m(2) TMZ and RT (n = 5). A standard 3 + 3 dose-escalation design was used to determine the maximum tolerated dose. Patients were evaluated for adverse events (AEs), plasma pharmacokinetics, pharmacodynamic effects in skin biopsies, and tumor response. RESULTS: The maximum tolerated doses were 90 mg q.d. and 40 mg b.i.d. for voxtalisib in combination with TMZ. The most frequently reported treatment-related AEs were nausea (48%), fatigue (43%), thrombocytopenia (26%), and diarrhea (24%). The most frequently reported treatment-related grade ≥3 AEs were lymphopenia (13%), thrombocytopenia, and decreased platelet count (9% each). Pharmacokinetic parameters were similar to previous studies with voxtalisib monotherapy. Moderate inhibition of PI3K signaling was observed in skin biopsies. Best response was partial response in 4% of evaluable patients, with stable disease observed in 68%. CONCLUSIONS: Voxtalisib in combination with TMZ with or without RT in patients with high-grade gliomas demonstrated a favorable safety profile and a moderate level of PI3K/mTOR pathway inhibition.

A phase I study of bevacizumab (B) in combination with everolimus (E) and erlotinib (E) in advanced cancer (BEE).

PURPOSE: VEGF, mTOR, and EGFR inhibitors have demonstrated anti-tumor and anti-angiogenic effects alone and in combination with each other. This study evaluated the safety, tolerability, and pharmacokinetics of bevacizumab, everolimus, and erlotinib combination. METHODS: Doublet therapy consisted of bevacizumab at 10 mg/kg every 14 days and everolimus 5 mg daily which escalated to 10 mg daily. Erlotinib 75 mg daily was added to the phase II dose recommended phase II dose (RPTD) of bevacizumab and everolimus. Dose-limiting toxicity (DLT) was assessed in cycle 1. RESULTS: Forty-eight patients with advanced solid malignancies were evaluable for DLT and efficacy. No DLTs were observed in the doublet dose escalation. Two DLTs (grade 3 mucositis and grade 3 rash) were observed with the addition of erlotinib 75 mg daily. Consequently, triplet doses were adjusted and were better tolerated. Four patients had a partial response. Median progression-free survival (PFS) for the doublet therapy was 6.0 months (0.5 to 32+ months) and 5.5 months (0.8 to 27+ months) for the triplet therapy. Systemic exposure of everolimus was significantly higher in combination with erlotinib (476 ± 161 ng h/mL) compared to when given alone (393 ± 156 ng h/mL; P = 0.020). CONCLUSIONS: The RPTD for the doublet therapy is bevacizumab 10 mg/kg every 14 days and everolimus 10 mg daily, and the RPTD for the triplet therapy is bevacizumab 5 mg/kg every 14 days, everolimus 5 mg and erlotinib 75 mg daily. Prolonged disease stability was demonstrated in tumors known to respond to mTOR inhibition and potentially resistant to VEGF blockade.

Phase I study of pazopanib in combination with weekly paclitaxel in patients with advanced solid tumors.

PURPOSE: To evaluate the maximum tolerated regimen (MTR), dose-limiting toxicities, and pharmacokinetics of pazopanib, an oral small-molecule tyrosine kinase inhibitor of vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and c-Kit, in combination with paclitaxel. PATIENTS AND METHODS: Pazopanib was given daily with weekly paclitaxel on days 1, 8, and 15 every 28 days. Dose levels of pazopanib (mg/day)/paclitaxel (mg/m(2)) were 400/15, 800/15, 800/50, and 800/80. An expanded cohort was enrolled at the MTR. Plasma samples were collected to evaluate the effect of pazopanib, an inhibitor of cytochrome P450 (CYP)3A4, on the pharmacokinetics of paclitaxel, a CYP3A4 and CYP2C8 substrate. RESULTS: Of 26 enrolled patients, 17 were treated at the MTR of 800 mg pazopanib and 80 mg/m(2) paclitaxel. Dose-limiting toxicities included a grade 3 abscess and grade 2 hyperbilirubinemia. Other toxicities included elevated liver transaminases and diarrhea. Six patients (23%) had partial responses and 15 patients (58%) had stable disease. Administration of 800 mg pazopanib resulted in a 14% lower paclitaxel clearance and a 31% higher paclitaxel maximal concentration than with administration of paclitaxel alone at 15, 50, and 80 mg/m(2). At the MTR, coadministration of 800 mg pazopanib and 80 mg/m(2) paclitaxel resulted in a 26% higher geometric mean paclitaxel area under the curve. CONCLUSION: Pazopanib, at a dose of 800 mg daily, can be safely combined with a therapeutic dose of paclitaxel at 80 mg/m(2) when administered on days 1, 8, and 15, every 28 days. The observed greater plasma concentrations of paclitaxel given concurrently with pazopanib suggest that pazopanib is a weak inhibitor of CYP3A4 and CYP2C8.

A Phase II, open-label study evaluating pazopanib in patients with recurrent ovarian cancer.

OBJECTIVE: The progression-free and median survival of patients with advanced ovarian cancer has not appreciably improved over the last decade. Novel targeted therapies, particularly antiangiogenic agents, may potentially improve clinical outcomes in patients with ovarian cancer. This phase II, open-label study evaluated oral pazopanib monotherapy in patients with low-volume recurrent ovarian cancer. METHODS: Patients with recurrent epithelial ovarian, fallopian tube, or primary peritoneal carcinoma with complete CA-125 response to initial platinum-based chemotherapy and subsequent elevation of CA-125 to ≥ 42 U/mL (> 2 × ULN) were treated with pazopanib 800 mg once daily until PD or unacceptable toxicity. This Green-Dahlberg study required 2 CA-125 responses in stage I (20 patients) to proceed to stage II (15 patients). The primary endpoint was CA-125 response (≥ 50% decrease from baseline, confirmed ≥ 21 days after initial evaluation). RESULTS: Eleven of 36 patients (31%) had a CA-125 response to pazopanib, with median time to response of 29 days and median response duration of 113 days. Overall response rate was 18% in patients with measurable disease at baseline. The most common adverse events leading to discontinuation of study drug were grade 3 ALT (8%) and AST (8%) elevation. Only 1 grade 4 toxicity (peripheral edema) was reported. CONCLUSIONS: Pazopanib monotherapy was relatively well tolerated, with toxicity similar to other small-molecule, oral angiogenesis inhibitors, and demonstrated promising single-agent activity in patients with recurrent ovarian cancer. Further studies evaluating the potential role of pazopanib in patients with ovarian cancer are ongoing.

Pooled analysis of phase II window studies in children with contemporary high-risk metastatic rhabdomyosarcoma: a report from the Soft Tissue Sarcoma Committee of the Children's Oncology Group.

PURPOSE: The Soft Tissue Sarcoma Committee of the Children's Oncology Group has conducted five upfront window trials in patients with newly diagnosed metastatic rhabdomyosarcoma to identify promising new treatment agents. PATIENTS AND METHODS: This pooled analysis identified a total of 420 patients (115 from Intergroup Rhabdomyosarcoma Study III [IRS-III] and 305 from the five window trials). We assessed window therapy response rate, failure-free survival (FFS), and overall survival (OS). RESULTS: Response rates (complete + partial response) assessed at week 6 of window therapy ranged from 41% to 55% and did not predict FFS (P = .073) or OS (P = .31). FFS was influenced by trial (P = .048); patients enrolled onto IRS-III and the ifosfamide/etoposide and ifosfamide/doxorubicin trials fared best. When grouped and compared with topoisomerase I poison trials, ifosfamide/topoisomerase II inhibitor trials had superior FFS (P = .013). However, there was no difference in survival. CONCLUSION: Upfront phase II window trials can efficiently provide robust estimates of activity for new agents and combinations in newly diagnosed patients with high-risk rhabdomyosarcoma. Our data indicate that, for some phase II window trials, the risk of treatment failure may be increased but that the trend towards lower survival for some of the window trials compared with IRS-III is not statistically significant. Window nonresponders did not suffer worse FFS or OS than patients who responded to window therapy. Finally, these results provide a rationale for incorporating ifosfamide, etoposide, doxorubicin, and topoisomerase I poisons in future trials of high-risk metastatic rhabdomyosarcoma.