Phase 2 placebo-controlled, double-blind trial of dasatinib added to gemcitabine for patients with locally-advanced pancreatic cancer

Background

Pancreatic ductal adenocarcinoma (PDAC) has a high mortality rate with limited treatment options. Gemcitabine provides a marginal survival benefit for patients with advanced PDAC. Dasatinib is a competitive inhibitor of Src kinase, which is overexpressed in PDAC tumors. Dasatinib and gemcitabine were combined in a phase 1 clinical trial where stable disease was achieved in two of eight patients with gemcitabine-refractory PDAC.

Patients and methods

This placebo-controlled, randomized, double-blind, phase II study compared the combination of gemcitabine plus dasatinib to gemcitabine plus placebo in patients with locally advanced, non-metastatic PDAC. Patients received gemcitabine 1000 mg/m2 (30-min IV infusion) on days 1, 8, 15 of a 28-day cycle combined with either 100 mg oral dasatinib or placebo tablets daily. The primary objective was overall survival (OS), with safety and progression-free survival (PFS) as secondary objectives. Exploratory endpoints included overall response rate, freedom from distant metastasis, pain and fatigue progression and response rate, and CA19-9 response rate.

Results

There was no statistically significant difference in OS between the two treatment groups (HR = 1.16; 95% confidence interval [CI]: 0.81-1.65; P = 0.5656). Secondary and exploratory endpoint analyses also showed no statistically significant differences. The burden of toxicity was higher in the dasatinib arm.

Conclusions

Dasatinib failed to show increased OS or PFS in patients with locally advanced PDAC. Alternative combinations or trial designs may show a role for src inhibition in PDAC treatment.

A randomized, placebo-controlled phase III trial of masitinib plus gemcitabine in the treatment of advanced pancreatic cancer

BACKGROUND

Masitinib is a selective oral tyrosine-kinase inhibitor. The efficacy and safety of masitinib combined with gemcitabine was compared against single-agent gemcitabine in patients with advanced pancreatic ductal adenocarcinoma (PDAC).

PATIENTS AND METHODS

Patients with inoperable, chemotherapy-naïve, PDAC were randomized (1 : 1) to receive gemcitabine (1000 mg/m(2)) in combination with either masitinib (9 mg/kg/day) or a placebo. The primary endpoint was overall survival (OS) in the modified intent-to-treat population. Secondary OS analyses aimed to characterize subgroups with poor survival while receiving single-agent gemcitabine with subsequent evaluation of masitinib therapeutic benefit. These prospectively declared subgroups were based on pharmacogenomic data or a baseline characteristic.

RESULTS

Three hundred and fifty-three patients were randomly assigned to receive either masitinib plus gemcitabine (N = 175) or placebo plus gemcitabine (N = 178). Median OS was similar between treatment-arms for the overall population, at respectively, 7.7 and 7.1 months, with a hazard ratio (HR) of 0.89 (95% CI [0.70; 1.13]. Secondary analyses identified two subgroups having a significantly poor survival rate when receiving single-agent gemcitabine; one defined by an overexpression of acyl-CoA oxidase-1 (ACOX1) in blood, and another via a baseline pain intensity threshold (VAS > 20 mm). These subgroups represent a critical unmet medical need as evidenced from median OS of 5.5 months in patients receiving single-agent gemcitabine, and comprise an estimated 63% of patients. A significant treatment effect was observed in these subgroups for masitinib with median OS of 11.7 months in the 'ACOX1' subgroup [HR = 0.23 (0.10; 0.51), P = 0.001], and 8.0 months in the 'pain' subgroup [HR = 0.62 (0.43; 0.89), P = 0.012]. Despite an increased toxicity of the combination as compared with single-agent gemcitabine, side-effects remained manageable.

CONCLUSIONS

The present data warrant initiation of a confirmatory study that may support the use of masitinib plus gemcitabine for treatment of PDAC patients with overexpression of ACOX1 or baseline pain (VAS > 20mm). Masitinib's effect in these subgroups is also supported by biological plausibility and evidence of internal clinical validation.

TRIAL REGISTRATION

ClinicalTrials.gov:NCT00789633.

Efficacy of venlafaxine for the prevention and relief of oxaliplatin-induced acute neurotoxicity: results of EFFOX, a randomized, double-blind, placebo-controlled phase III trial

BACKGROUND

Oxaliplatin neurosensory toxicity is dose limiting and may present as acute symptoms and/or cumulative peripheral neuropathy.

PATIENTS AND METHODS

From October 2005 to May 2008, patients with oxaliplatin-induced acute neurotoxicity were randomized into a double-blind study, to receive either venlafaxine 50 mg 1 h prior oxaliplatin infusion and venlafaxine extended release 37.5 mg b.i.d. from day 2 to day 11 or placebo. Neurotoxicity was evaluated using numeric rating scale (NRS) for pain intensity and experienced relief under treatment, the Neuropathic Pain Symptom Inventory and the oxaliplatin-specific neurotoxicity scale. The primary end point was the percentage of patients with a 100% relief under treatment.

RESULTS

Forty-eight patients were included (27 males, median age: 67.6 years). Most patients had colorectal cancer (72.9%). Median number of cycles administered at inclusion was 4.5 (mean cumulative oxaliplatin dose: 684.6 mg). Twenty out of 24 patients in arm A (venlafaxine) and 22 out of 24 patients in arm B (placebo) were assessable for neurotoxicity. Based on the NRS, full relief was more frequent in the venlafaxine arm: 31.3% versus 5.3% (P=0.03). Venlafaxine side-effects included grade 1-2 nausea (43.1%) and asthenia (39.2%) without grade 3-4 events.

CONCLUSION

Venlafaxine has clinical activity against oxaliplatin-induced acute neurosensory toxicity.

Phase II study of carboplatin and etoposide in patients with anaplastic progressive metastatic castration-resistant prostate cancer (mCRPC) with or without neuroendocrine differentiation: results of the French Genito-Urinary Tumor Group (GETUG) P01 trial

BACKGROUND

In the evolution of metastatic castration-resistant prostate cancer (mCRPC), patients present visceral metastases with or without neuroendocrine differentiation in 20% of cases.

PATIENTS AND METHODS

We assessed the efficacy and toxicity of a platinum-based chemotherapy regimen in mCRPC patients with either neuroendocrine differentiation defined by high serum levels of chromogranin A (CgA) and neuron-specific enolase (NSE) or visceral metastases. Patients received the combination of carboplatin and etoposide every 3 weeks. Efficacy end points included prostate-specific antigen (PSA) and neuroendocrine marker response, objective response and toxicity.

RESULTS

Of the 60 patients included from April 2005 to January 2008, 78.6% had bone metastases, 46.4% had lymph node involvement and 57.1% had liver and/or lung localizations. The objective response rate was 8.9% in the 46 patients with measurable disease. A neuroendocrine response was observed in 31% of cases for NSE and 7% for CgA. The PSA response rate was 8%. The most common grade 3-4 treatment-related toxic effects were neutropenia (65.5%), thrombocytopenia (32.7%) and anemia (27.3%). There was 7.2% febrile neutropenia, with one toxicity-related death. The median follow-up was 9.3 months [95% confidence interval (CI) 0.2-27.1] and the median overall survival 9.6 months (95% CI 8.7-12.7).

CONCLUSION

The benefit-risk ratio of this regimen seems unfavorable due to poor response and high toxicity.

Dose-finding and efficacy phase II study of inecalcitol, a new VDR agonist, in combination with docetaxel-prednisone regimen for castration-resistant prostate cancer (CRPC) patients (pts)

142

Background: Inecalcitol is a novel vitamin D receptor (VDR) agonist which shows high antiproliferative effects in human cancer cell lines and a 100-fold lower hypercalcemic activity than calcitriol the natural ligand of VDR.

Methods: Escalating dosages of inecalcitol were combined to chemotherapy in naive metastatic CRPC patients. Safety and efficacy were evaluated in groups of 3-6 pts receiving inecalcitol every other day, daily or twice a day on a 21-day cycle in combination with docetaxel (75mg/m2 q3w) and oral prednisone (5mg bid). Pts received up to six cycles unless unacceptable toxicity or disease progression. Primary endpoint was dose limiting toxicity (DLT) defined as G3 hypercalcemia within the first cycle. Efficacy endpoint was PSA response defined as ≥30% decline within 3 months.

Results: Eight dose levels from 40 to 8,000 μg have been evaluated in 54 pts; 83 % had bone metastases, 13% had visceral disease only. Median age was 71 years (range, 49-87), median Gleason score (Gs) 7 and median PSA 28.5 ng/mL (range, 0.8-962.4). DLT occurred in 2/4 patients receiving 8,000 μg/day after 1 and 2 weeks of treatment. Calcemia normalized in few days after interruption of treatment. The 2 other experienced only G2 and were stepped down to 4,000 μg. After dose reduction, calcemia remained within normal ranges and G1.The maximum tolerated dose is defined at 4,000 μg qd. Most of adverse events reported were grade 2. G3-4 were mainly hematological toxicity. Frequency of AEs related to docetaxel did not seem to be modified.82% of the patients had ≥30% PSA decline within 3 months of treatment whereas in historical data around 65% are responder with docetaxel as a single agent. PSA response was observed after 1 cycle of treatment in 43% of the patients. Time to biochemical relapse defined as an increase of 25% over nadir was 169 days.

Conclusions: High antiproliferative daily dose of inecalcitol, a new VDR, agonist has been safely used in combination with docetaxel in CRPC patients. This combination treatment shows encouraging PSA response (> 30% PSA response: 82%). A multicenter randomized double blind phase III study is forecasted to confirm these results.

[Table: see text]

Oral tyrosine kinase inhibitor masitinib in combination with gemcitabine in patients with advanced pancreatic cancer: A multicenter phase II study

4617

Background: Masitinib, a tyrosine kinase inhibitor targeting c-Kit, PDGFR, FGFR3 and affecting the FAK pathway, can enhance the antiproliferative effects of gemcitabine (GEM) in human pancreatic cancer cells. This multicenter phase 2 study aimed to determine the efficacy and safety of masitinib in combination with GEM in the first-line treatment of patients with locally advanced (LAPC) or metastatic (MPC) pancreatic cancer. Methods: Patients received oral masitinib (9 mg/kg/d) and standard weekly infusion of GEM (1,000 mg/m2). Primary endpoint was time-to-progression (TTP). Our hypothesis for efficacy was a TTP over 2.1 months. Secondary endpoints included survival rates, tumor response (RECIST) and clinical benefit. Results: 22 patients, with LAPC (n=9) or MPC (n=13), KPS[80–100]/[70] (18/4) were enrolled and treated with masitinib plus GEM. Median TTP was 6.4 months, well beyond our threshold for efficacy (LAPC: 8.3 months, MPC: 2.7 months, KPS[80–100]: 6.4 months, KPS[70]: 0.8 months). At 12 months, 17% of LAPC and 14% of KPS[80–100] were progression-free; all MPC and KPS[70] patients had progressed. The disease control rate was 73% (LAPC: 89%, MPC: 62%, KPS[80–100]: 89%; KPS[70] patients progressed immediately). Median OS was 7.1 months (LAPC: 8.4 months, MPC: 6.8 months, KPS[80–100]: 8.0 months, KPS[70]: 4.4 months). At 18 months, the survival rate was 23%. However, when considering KPS[80–100] alone, it reached 28%. The 18-months survival rates were similar for LAPC (22%) and MPC (23%). 16% of the 19 patients evaluated experienced clinical benefit (LAPC: 38%, KPS[80–100]: 18%). One patient (5%) presented suspected grade 4 neutropenia. Main suspected grade 3 toxicity were anemia, lymphopenia (23%), leucopenia, neutropenia (18%), asthenia (14%), diarrhea, cytolytic hepatitis, and skin rash (9%). Altogether, the combination masitinib plus GEM did not seem to increase the toxicity commonly reported with GEM alone. Conclusions: The antitumor activity of the combination masitinib plus GEM is very promising and does not present limiting toxicities. Based on those encouraging data, a randomized phase III trial comparing masitinib plus GEM with GEM alone is now actively recruiting patients in the US and in Europe.

[Table: see text]

Efficacy of venlafaxine for the prevention and relief of acute neurotoxicity of oxaliplatin: Results of EFFOX, a randomized, double-blinded, placebo-controlled prospective study

9533

Background: Neurosensory toxicity of oxaliplatin is dose-limiting and presents as two distinct clinical syndromes: acute symptoms and cumulative peripheral neuropathy. Methods: From October 2005 to May 2008, patients (pts) presenting oxaliplatin-induced acute neurotoxicity were randomized in a double-blinded study, to receive either arm A: venlafaxine hydrochloride (Effexor, Wyeth Pharmaceuticals Inc.) 50 mg 1 hour prior oxaliplatin infusion and venlafaxine extended release 37.5 mg b.i.d. from day 2 to day 11, either arm B : placebo. The primary endpoint was percentage of pts without acute neuropathy. The study was designed to detect, with 54 pts, a difference of 25%. The neurotoxicity was evaluated using a numeric rating scale of symptoms relief and the Neuropathic Pain Symptom Inventory (Pain 2004;108(3):248–57). Results: 45 pts were included (male : 24; median age : 67.5). Most pts had colo-rectal cancer (75.6%). The two most used chemotherapy regimens were FOLFOX (82.2%) and GEMOX (11.1%). Median number of cycles administered at inclusion was 5. In January 2009, 16 pts out of 22 in arm A (venlafaxine) and 21 pts out of 23 in arm B (placebo) were evaluable. Venlafaxine reduced the incidence of neurosensory acute symptoms : 35.3 % in arm A vs 76.2% in arm B (p=.023, Fisher's exact test). Side effects were emesis (4 pts) and somnolence (3 pts). Conclusions: Venlafaxine is effective for prevention and relief of oxaliplatin-induced acute neurotoxicity.

No significant financial relationships to disclose.

Results of a phase II study of carboplatin and etoposide in patients with progressive metastatic castration refractory prostate cancer (mCRPC) and neuro-endocrine differentiation

e16073

Background: Neuro-endocrine differentiation is often observed in the evolution of mCRPC. We assessed the efficacy and toxicity of a platin-based chemotherapy regimen in patients with mCPRC and neuro-endocrine differentiation defined by: either increased circulating neuro-endocrine markers (chromogranin A: CgA, Neuron Specific Enolase: NSE) more than 1.5 X normal serum values and/or visceral metastases confirmed with immunihistochemical proof of neuro-endocrine differentiation on pathological sample. Methods: Sixty patients were included (Simon optimal two stages design with P0 = 20%, P1 = 40%, α = 5% and power 90% for a total of 54 evaluable patients) and were treated by the combination of carboplatin AUC 4 d1 IV and etoposide 100 mg/m2/d d1–3 IV every 3 weeks for a maximum of 6 cycles. Efficacy endpoints included PSA and neuro-endocrine marker response rate (defined as a decrease of 50% or greater of the baseline serum value), objective response rate (according to RECIST criteria), and toxicity. Results: Sixty patients were included between April 2005 to January 2008, median age was 67 (range: 45–80). Sixty-seven per cent patients received prior chemotherapy. Patients had bone metastases (78%), lymph nodes involvement (49%), lung metastases (35%), hepatic involvement (33%) and other localizations (17%). The objective response rate was 33% in the 48 assessable patients. A neuro-endocrine response was observed in 28% of 32 evaluable patients for neuro-endocrine marker level (CgA 6%, NSE 25% and both 3%). The PSA response rate was 9%. The most common grade 3–4 treatment-related toxicities were neutropenia (67%), thrombocytopenia (31%), anemia (27%), asthenia (14%) nausea and vomiting grade (12%). There were 6% febrile neutropenia, with one related toxic death. The median follow-up is 9 months. The median response duration was 1.8 months (range: 0.2–13.4 months). The median overall survival is 10 months. Conclusions: Despite an absolute response rate in accordance with the study assumptions, the benefit-risk ratio of this regimen seems unfavourable due to observed toxicities. Another trials must be conducted in order to define a group of patients which may benefit of this regimen.

No significant financial relationships to disclose.

Dose finding and safety analysis of inecalcitol in combination with a docetaxel-prednisone regimen in hormone-refractory prostate cancer (HRPC) patients

5151

Background: Inecalcitol is a novel synthetic vitamin D3 analogue with potent antiproliferative effects in human cancer cell lines and a 100-fold lower hypercalcemic activity than calcitriol in animal models. Methods: Escalating dosages of inecalcitol were combined to chemotherapy in naive HRPC patients (pts). Safety and efficacy were evaluated in groups of 3–6 patients receiving oral inecalcitol daily or every other day on a 21-day cycle in combination with docetaxel (75mg/m2 q3w) and oral prednisone (5mg bid). Biphosphonates were prohibited during the first cycle. Patients received up to six cycles unless unacceptable toxicity or disease progression. Primary endpoint was dose limiting toxicity (DLT) defined as grade 3 hypercalcemia within the first cycle. Calcemia, creatininemia and CBC were assessed weekly; biochemistry, ECG and PSA every 3 weeks. Efficacy endpoint was PSA response defined as ≥30% decline within 3 months. Results: Five dose levels: 40, 80, 160, 300, 600 μg have been evaluated in 34 pts; 9 pts are still being treated at 600 μg; 25 pts have completed 6 cycles (13 bone metastases; 3 extrasqueletic metastasis, 8 bone and extrasqueletic metastases; 1 PSA-only disease). Median age was 72 years (range, 53–87), median Gleason score (Gs) 7 (36% Gs 10–8, 64% Gs 7–6) and median PSA 41.5 ng/mL (range, 0.9–962.4). No increased calcemia was reported. Most adverse events (AE) were G1–2, asthenia (19pts), constipation (14pts), diarrhea (13pts). G3–4 AEs were neutropenia (11pts) lymphopenia (9pts), asthenia (3pts), arrhythmia (2 pts), general health deterioration (2pts) and diarrhea (1pt). None of these AEs was considered related to inecalcitol. Of the 23 evaluable pts for PSA response, 20 (87%) had ≥30% PSA decline. Conclusions: Results from this ongoing study show the safe profile of inecalcitol when given daily in in HRPC pts. PSA responses with this combination are encouraging. As DLT was not reached, a higher dose of inecalcitol (1000 μg/day) will be further tested.

[Table: see text]

Trastuzumab (T) combined with standard chemotherapy in HER+ metastatic bladder cancer (BC) patients: Interim safety results of a prospective randomized phase II study

15565

Background: Almost 25% of BC patients overexpressed HER2 and 50 to 60% of them are responding to the combination of T with standard chemotherapy (gemcitabine and platinum salt). A prospective, randomized, European phase II study comparing this association with conventional chemotherapy alone is ongoing. Methods: Eligible HER+ BC pts were required to have an advanced and chemonaive bladder cancer and ECOG performance status (PS) 0–2. The aim is to demonstrate a progression-free survival benefit for investigational arm. Sample size was estimated at 126 patients, with a two-sided alpha and beta levels at 5 and 80%, respectively. Treatment-related toxicities were evaluated using CTC-NCI version 2. Fisher exact test was the main statistical method testing differences in percentage of toxicities. Results: Thirty-seven patients were included in 11 centres between February 2004 and December 2006. The planned safety interim analysis was performed after inclusion of 30 patients (15 in each arm). Median age was 59 years (range 46- 80), 93% of patients are men. Seven percent have an advanced disease, 33% have more than one single metastatic site and 83% were PS ECOG 0–1. There were no significant differences between arms concerning hematological and non-hematological all grade toxicities. Severe (grade III-IV) leucopenia, granulocytopenia, anemia and thrombocytopenia were registered in 53, 53, 33 and 60% for combined arm. Grade I-II of diarrhea was slightly more frequent for T arm. There were no differences for alopecia, constipation, nausea and edema. An asymptomatic reduction of the left ventricular ejection fraction was found in one patient in each arm. Conclusions: Combination of T with standard chemotherapy for BC patients was safe. No serious adverse events significant differences were registered, especially concerning T-related cardiac toxicities. The planned interim efficacy analysis is expected after inclusion of 60 patients.

No significant financial relationships to disclose.

Is intravenous (iv) IL2 superior to subcutaneous (sc) IL2 in good prognosis patients (pts) with metastatic renal cell carcinoma (MRCC) receiving a combination of IL2 and alpha interferon (IFN)? Results of the prospective randomized PERCY Duo trial

4536

Background: Pts with a single metastatic site are more likely to benefit from an IL2 and IFN combination (Negrier NEJM 1998). The French Immunotherapy Intergroup designed a multicenter trial to assess the potential benefit of iv over sc IL2 in IL2+IFN combination in this subgroup. Methods: Untreated pts, Karnofsky score ≥ 90 and a single metastatic site were randomized into this 2 arm trial. Pts received continuous IL2 infusion (18 million IU/m2/d) (arm A), or sc IL2 injections (9 or 18 million IU) twice daily (arm B). IFN was given sc (6 million IU) 3d/week in both arms. Tumor responses (OMS criteria) were assessed at weeks 12 and 27. The primary endpoint was overall survival (OS), with an expected difference of 15% at 4 yrs in favor of iv IL2. The planned sample size was 220 to have 80% power at 5% significance level with a one-sided test. One intent-to-treat analysis was performed and survivals were compared using log-rank tests. Results: From January 00 to January 05, 80 and 75 pts were randomized to arms A and B respectively. Enrollment was stopped early due to low accrual; analysis was performed at 40-month median follow up. Patient characteristics were well balanced between groups. Median age was 55, 82% pts were male, 68% had lung metastases, and 37% had more than 1 year from renal tumor to metastases. No toxic death occurred, gr 3/4 vomiting, rise in creatinine level, hypotension and neurologic toxicity were significantly higher in arm A. Response rates were 17.9 vs 21.3%, in arms A and B, respectively. Progression-free survivals were not significantly different (P: 0.285). The difference in OS was not significant: median 37.7 months [95%CI: 28.2–58.4] with iv IL2 vs. 26.3 [95%CI: 24.5–34.2] with sc IL2 (P: 0.127). Conclusions: Iv IL2 combined with IFN confers no significant advantage over a sc IL2 combination in selected pts with good prognosis MRCC. Since some toxicities were significantly more frequent with iv IL2, the use of this combination cannot be recommended. Because of premature stop, the trend in favor of iv IL2 should encourage further studies before final conclusions can be drawn.

[Table: see text]

A phase II study of a paclitaxel and oxaliplatin combination in platinum-sensitive recurrent advanced ovarian cancer patients

PURPOSE

A multicentric, phase II study to evaluate the efficacy and safety of the combination paclitaxel and oxaliplatin in patients with platinum-sensitive recurrent ovarian cancer.

PATIENTS AND METHODS

Patients received 175 mg/m(2) paclitaxel (over 3 h) followed by 130 mg/m(2) oxaliplatin (over 2 h) every 21 days for up to nine cycles without hydration or primary granulocyte colony-stimulating factor prophylaxis. Patients had to have an Eastern Cooperative Oncology Group performance status of 0-2 and to have received no more than one prior cisplatin- and/or carboplatin-containing chemotherapy regimen with a platinum-progression-free interval > or =6 months.

RESULTS

Of the 105 patients enrolled and treated, 98 were eligible. An overall response rate of 81% (79 of 98 patients) (95% confidence interval 71% to 88%) was observed according to RECIST criteria (third party reviewed), and 88% (86 of 98) when this was complemented with CA-125 response. With a median follow up of 43.6 months (range 30.2-64.2) the median progression-free survival was 10.2 months (range 0.3-21.4) and the overall survival 32.4 months. Seven hundred and eight cycles were administered (median seven per patient; range one to nine). A total of 67% of patients experienced National Cancer Institute Common Toxicity Criteria grade 3-4 neutropenia, including 8% with concomitant febrile episode, without treatment-related deaths. Ninety-three per cent of patients experienced neuropathy of grade 1 or more, including 25% with cumulative reversible peripheral neuropathy of grade 3-4. Oxaliplatin doses were reduced in 30 patients due to neurotoxicity.

CONCLUSIONS

The oxaliplatin/paclitaxel combination can be administered in an outpatient setting every 3 weeks without specific measures. The high level of activity and its duration observed warrants further evaluation of this combination in pretreated platinum-sensitive advanced ovarian cancer patients.

Phase II trial of the antiangiogenic agent IM862 in metastatic renal cell carcinoma

IM862 is a naturally occurring dipeptide (L-glu-L-trp) with immunomodulatory and antiangiogenic properties. A significant anticancer activity has been reported recently in AIDS-related Kaposi's sarcoma, a tumour of endothelial cell origin. The high vascularity and responsiveness to immunotherapy of renal cell carcinoma (RCC) makes such a tumour a potential target for IM862. In all, 25 patients were accrued in a prospective phase II trial using a standard two-step design. The main inclusion criteria were WHO performance status ⩽2, age over 18 years, expected survival >3 months, normal marrow, kidney and liver functions. IM862 was given intranasally at a dose of 20 mg three times daily. Each cycle consisted of 8 consecutive weeks of treatment. All 25 patients were fully evaluable for response and 24 for toxicities. Median age was 62 years (range 42–76), median WHO PS was 1 (0–2). No grade 2 or 3 toxicities related to the study drug have been recorded. Eight patients had stable disease (SD) and 17 progressed while on treatment. Median survival was 7.9 months (range 2.7–20). Median time to progression was 1.9 months (range 1.2–12.6). Median duration of SD was 6 months (range 5.2–12.6+). Analysis of blood angiogenic markers showed a significant decrease of plasma vascular endothelial growth factor (VEGF) levels after 4 and 8 weeks of therapy. Treatment with IM862 has no toxicity, but does not lead to any significant objective responses in metastatic RCC. IM862 should not be further evaluated as a single agent at these doses and schedule for this population of patients. The decrease in VEGF levels warrants further investigation of IM862 as an antiangiogenic therapy.

Dose-finding study of weekly 24-h continuous infusion of 5-fluorouracil associated with alternating oxaliplatin or irinotecan in advanced colorectal cancer patients

PURPOSE

To determine maximum tolerated dose, safety and efficacy of weekly 24 h infusional 5-fluorouracil (5-FU) combined alternately with oxaliplatin and irinotecan.

PATIENTS AND METHODS

Advanced colorectal carcinoma patients in first- or second-line chemotherapy received increasing doses of 5-FU (weekly 24 h continuous intravenous infusion without leucovorin) on days 1, 8, 15 and 22, irinotecan days 1 and 15; and oxaliplatin days 8 and 22, every 35 days.

RESULTS

Thirty-four patients received 175 cycles. The median age was 64 years (range 47-78). Eighteen per cent of patients had the primary tumor in the rectum, with a median of one disease site (range one to three), and liver involvement in 88% and lung in 38%. Six (18%) patients had chemotherapy for prior advanced disease. The most frequent grade 3-4 toxicity was neutropenia (41% of patients), but the regimen was well tolerated clinically, with febrile neutropenia in two patients and grade 4 neutropenia lasting >7 days in one; grade 3-4 diarrhea, nausea and vomiting in 6% of patients; grade 3-4 peripheral neuropathy in 9% of patients. Seventeen patients had a partial response (50%; 95% confidence interval 33%-67%), 13 had stable disease and one had progressive disease. Five patients underwent metastatic surgical resection after tumor shrinkage. Median response duration was 14 months (range 4.7-29.2+) and median time to progression was 11.3 months (range 1.1+-30.7+).

CONCLUSIONS

This combination three-drug regimen is feasible and well tolerated without toxicity overlap. Preliminary antitumor activity compares well with standard double combinations, with an unusually long median time to progression. The recommended dose is 5-FU 3000 mg/m(2), weekly for 4 weeks, irinotecan 100 mg/m(2) days 1 and 15, oxaliplatin 80 mg/m(2) days 8 and 22. Further assessment of antitumor activity and safety is warranted.

Conflicting effects of caffeine on apoptosis and clonogenic survival of human K1 thyroid carcinoma cell lines with different p53 status after exposure to cisplatin or UVc irradiation

Caffeine has been widely described as a chemo/radiosensitizing agent, presumably by inhibiting DNA repair, and affecting preferentially cells with an altered p53 status. We evaluated the effects of caffeine using isogenic and isophenotypic K1 cells derived from a papillary thyroid carcinoma and displaying either a wild type or a mutated p53 status. Apoptosis and clonogenic survival were examined after exposure of the cells to cisplatin or UVc irradiation. We find that at the most currently used concentration, 2mM, caffeine hinders cisplatin or UVc induced apoptosis in K1 cells. In addition, at this already barely achievable concentration in vivo, caffeine does not decrease their clonogenic survival. Hence in our cellular model, caffeine does not behave as a chemo- or a radiosensitizer. Although surprising, these results (1) are in agreement with the delayed G2/M block caused by caffeine that we previously observed in normal human fibroblasts and K1 cells and (2) allow us to elucidate some discrepancies concerning this molecule throughout the literature such as increase or decrease of apoptosis and clonogenic survival, activation or deactivation of molecules involved in DNA damage repair and proliferation inhibition but accelerated G2/M traverse.

Comparison of prognostic factors in patients in phase I trials of cytotoxic drugs vs new noncytotoxic agents

The aims of this study were to identify prognostic variables for toxicity and survival in patients with cancer participating in phase I clinical trials and compare characteristics of those treated with cytotoxic chemotherapy (CT) and non-cytotoxic drugs (non-CT). Data were collected from 420 (114 CT, 306 non-CT) patients enrolled in 16 phase I trials (five CT and 11 non-CT trials) in one cancer centre. Analyses of all patients were used to compare treatment groups, identify predictive variables for toxicity and to estimate prognostic factors in overall survival (OS). These were used to develop a prognostic index (PI). Multivariate analysis found those patients with better performance status, fewer sites of metastases, baseline Hb>12 g dl⁻¹ and WBC or LDH in the normal range had significantly better OS. Male gender, platelet count <450 × 10⁹ l⁻¹, high WBC or treatment with a non-CT phase I agent significantly reduced the chance of grade 3/4 toxicity. Overall survival was not significantly different between the CT and non-CT groups (260 vs 192 days, P=0.47) except for those with liver metastases (228 vs 137 days, P=0.02). Overall tumour response was 4.9% (95% CI: 2.7–7.0%). The PI identified three distinct patient groups with median survival of 321, 257 and 117 days. In conclusion, entry into a phase I trial of a non-CT drug is a safe option for heavily pretreated patients with cancer. The PI generated from these data can estimate the survival probability for patients entering phase I studies.

Anti-angiogenic effects of the thienopyridine SR 25989 in vitro and in vivo in a murine pulmonary metastasis model

Neovascularisation is a key step in tumour growth and establishment of distant metastases. We have recently demonstrated that the thienopyridine SR 25989 an enantiomer of the anti-aggregant clopidogrel (Plavix) lacking anti-aggregant activity, inhibits endothelial cell proliferation in vitro by increasing the expression of endogenous thrombospondin-1, a natural potent inhibitor of angiogenesis. The anti-angiogenic effect of SR 25989 was further assessed in vitro in a quantitative assay of angiogenesis comprising a fragment of rat aorta embedded in a fibrin gel and in vivo in a pulmonary metastatic model using C57BL/6 mice inoculated in the foot pad with the highly metastatic melanoma cell line B16 F10. SR 25989 induced a dose dependent inhibition of spontaneous microvessel development in vitro reaching half maximal inhibition at around less than 50 microM and caused platelet derived growth factor induced angiogenesis to regress as a function of thienopyridine concentration. In vivo, SR 25989 did not alter significantly the growth rate of the primary tumour in the foot pad and did not inhibit development of inguinal nodes which appeared after amputation. However, the number and size of lung metastases were reduced in treated animals when examined at the time of sacrifice. In addition, the few metastases over 1 mm3 did not show any neovascularisation, as confirmed by negative von Willebrand immunostaining and in contrast to intense vascularisation seen in metastases developed by control mice. These results confirm that SR 25989 possesses potent anti-angiogenic properties and is able to inhibit metastatic dissemination and growth. The lack of effect on the primary tumour and inguinal nodes illustrates the complexity of the mechanisms involved in tumoural neo-angiogenesis and points out the possibility for distinct processes leading to neovascularisation in primary tumour as opposed to metastases.

Caffeine and the G2/M block override: a concept resulting from a misleading cell kinetic delay, independent of functional p53

In the literature the sensitization of DNA to radiation-induced damage by caffeine has been attributed to an override of the G2/M block. This process was supposed to involve the tumor suppressor gene p53 as it was described that p53 negative cells were more sensitive to checkpoint inhibition by caffeine than the wildtype phenotype. We have recently shown that caffeine does not cause an override of the G2/M block induced by radiation in normal human fibroblasts. We demonstrate here that this also applies to a human transformed cell line, the thyroid carcinoma K1, when submitted to gamma- rays irradiation. Within 9 hr after irradiation over 70% of the cells accumulated in the G2/M phase. This block persisted at 16 hr. In caffeine containing cultures the percentage of cells attaining the G2/M phase was reduced by over 30% at 16 hr. This was reflected in an accumulation of the cells in G1 phase and an inhibition of the S phase traverse. Cell cycle analyses from further time points combined with cell proliferation measurements confirmed these data. These results were independent of p53 status as experiments performed with variant K1 cell lines having defective p53 functions, led to similar conclusions. In addition, caffeine restored a G1 delay after irradiation in the cell lines with abrogated p53 functions. The effects of caffeine undeniably cumulate with damages induced by irradiation but probably by inhibiting DNA repair mechanisms or by intervening with purine and pyrimidine metabolisms and not by causing a G2/M block override.

Anti-angiogenic agents: clinical trial design and therapies in development

Development of therapies aimed at inhibiting the growth of new blood vessels is among the most intensively studied approaches to the treatment of cancer. Deciphering the many biological processes involved in tumour angiogenesis has led to the development of new agents targeting either metalloproteases, angiogenic growth factors, endothelial cells or other components of the tumour neovasculature. More than 35 anti-angiogenic agents have already entered clinical trials in cancer patients and most of them are reviewed here. It has rapidly emerged from the preliminary results of these studies that the steps and endpoints classically adopted and used worldwide in developing new anticancer agents could be inappropriate to assess the efficacy of agents that do not target cancer cells directly. One of the major challenges for scientists and clinical researchers is to define new surrogate endpoints adapted to anti-angiogenic agents in the design of clinical trials. Once this has been achieved, the place of clinically active anti-angiogenic agents will need to be further refined in order to determine where they best fit in our current armamentarium, either as single agents or in combination with classical anticancer therapies. Finally, the use of these new agents may in the future encompass every aspect of cancer management, not only from palliative to curative treatment but also in the prevention of cancer.

Caffeine does not cause override of the G2/M block induced by UVc or gamma radiation in normal human skin fibroblasts

Caffeine has for many years been known to be involved in the sensitization of DNA to damage. One potential mechanism recently put forward is an override of the G2/M block induced by irradiation, which would leave the cells less time for DNA repair prior to mitosis. However, different cell types display a variety of responses and no clear pathway has yet emerged, especially as little is known about the capacity of this agent to enhance DNA damage in normal, untransformed cells. Continuous exposure to commonly used caffeine concentrations (1-5 mM) inhibited the proliferation of normal human fibroblasts (NHFs) in a dose-dependent manner to up to 80% at 5 mM. Exposure of exponentially growing NHFs to UVc radiation (20 J m(-2)) or gamma radiation (2.5-8 Gy) led to a 45-60% inhibition of proliferation and protracted accumulation of cells in the G2/M phase. Addition of 2 mM caffeine after irradiation induced slowing of the S phase passage, with a resultant delay in G2/M accumulation mimicking a G2/M block override. These results were confirmed by stathmokinetic studies, which showed delayed entry of the cells into mitosis in the presence of caffeine. Our data demonstrate that caffeine primarily inhibits replicative DNA synthesis and suggest that, at least in normal cells, caffeine potentiates the cytotoxicity of radiation by intervening in DNA repair rather than by overriding the G2/M block.

p53-independent regulation of cyclin B1 in normal human fibroblasts during UV-induced G2-arrest

Recently we demonstrated, using normal human fibroblasts (NHFs), that UVc radiation induces a G2/M arrest which was even more pronounced when p53 expression was inhibited. So, the aim of this study was to evaluate in NHFs the relationship between UV-induced G2/M arrest and cyclin B1 regulation and to investigate if p53 could contribute to the cyclin B1 regulation in these conditions. Following exposure of asynchronous NHFs to UV light, we showed that the induced G2/M arrest was accompanied by a dose-dependent down-regulation of cyclin B1 mRNA as evaluated by RT-PCR. Concomitantly, using flow cytometric analysis, we observed a strong accumulation of cyclin B1 protein which was correlated to the apparition of the G2/M arrest. In order to study the contribution of p53 to the cyclin B1 accumulation in response to UV exposure, we inhibited p53 induction using p53 antisense oligonucleotides. We found that the inhibition of p53 protein induction after UV exposure had no effect on the level of cyclin B1 mRNA. Moreover, although inhibition of p53 protein induction increased the number of the cells in the G2-M phase, the mean content of cyclin B1 protein was not augmented in these cells. These results indicate clearly that the induction of p53 protein following UV exposure does not regulate the level of cyclin B1 mRNA or protein in normal cells.

Paclitaxel-anthracycline combination chemotherapy in relapsing advanced ovarian cancer after platinum-based chemotherapy: a pilot study

Despite high response rates with platinum-based front-line chemotherapy, the prognosis for advanced ovarian carcinoma (AOC) is poor. Salvage chemotherapy for recurrent AOC was of little benefit before paclitaxel as single-agent therapy showed appreciable efficacy. Anthracyclines are effective, but are not often part of first-line therapy. In this pilot study, we investigated the feasibility of an anthracycline plus paclitaxel combination therapy for recurrent AOC. Twenty-four patients received 150 mg/m2 paclitaxel on day 1, with either 50 mg/m2 doxorubicin on day 1 or 75 mg/m2 epirubicin on day 1 every 3 weeks. A 27% overall response rate was obtained. Myelosuppression was the major toxicity, but was manageable. No myocardiac toxicity was observed. We conclude that paclitaxel-anthracyclines is a promising salvage combination therapy in AOC that should be investigated further.

Inactivation of p53 in normal human cells increases G2/M arrest and sensitivity to DNA-damaging agents

p53 mutations are found in about 70% of human cancers. In order to evaluate the role of these mutations in response to chemotherapeutic agents, it is important to distinguish between p53 response to DNA-damaging agents in normal and in tumour cells. Here, using normal human fibroblasts (NHFs), we show that cisplatin and UV radiation induce G2/M arrest which is temporally linked to p53-protein induction. To study the contribution of p53 to this G2/M arrest, we inhibited p53 induction in NHFs using p53 anti-sense oligonucleotides. Following exposure of NHFs to UV radiation, the inhibition of p53-protein induction leads to a greater accumulation of cells in the G2/M phase, but also to a decreased fraction of cells in the G1 phase. We propose that p53 does not induce G2/M arrest directly, and that the extent of this arrest may depend on the fraction of cells that do not stop at the G1 phase following exposure to DNA-damaging agents. Furthermore, inhibition of p53-protein induction leads to increased sensitivity of NHFs to UV radiation. These results suggest that inhibition of p53 protein enhances sensitivity to DNA-damaging agents in normal human cells.

[Relationships between p53 induction, cell cycle arrest and survival of normal human fibroblasts following DNA damage]

It is now well established that in response to genotoxic stresses mammalian cells show an increased p53 protein levels and undergo cell cycle arrest at G1/S and G2/M checkpoints. But, the consequences of these cell cycle arrests on cell survival are not yet elucidated. In this study, we have analysed the relationships between p53 protein induction, cell cycle arrest and cell survival following exposure of normal human fibroblasts (NHFs) to various genotoxic agents such as cisplatin, UV radiation and gamma radiation. p53 protein accumulation and G2/M arrest arose at the same time following exposure to DNA damaging agents, suggesting that p53 is responsible for the G2/M block. However, following inhibition of p53 induction by an antisense oligonucleotide, this G2/M arrest is even more important and correlates with an enhanced sensitivity of NHFs to UV radiation. In addition, there appears to be a threshold in the response of NHFs to DNA damaging agents, p53 induction and cell cycle arrest being observed only with lethal UV doses. We show that: 1) there appears to be a threshold in the cellular response to genotoxic agents, below which neither p53 induction, nor cell cycle arrest, nor cell survival alteration occur and beyond which p53 induction is accompanied by cell cycle arrest and decreased cell survival; 2) although there is a tight temporal relationship, the onset of which depends of the DNA damaging agent used, between the start of p53 induction and the occurrence of G2/M arrest, this latter is independent of p53; 3) p53 inhibition enhances NHFs' sensitivity to DNA damaging agents, the extent of the G2/M arrest correlating with decreased cell survival. Finally, the lack of obligatory correlation between p53 inactivation, apoptosis and radio- or chemoresistance is discussed.