Nebojsa Manojlovic

A phase 3 trial evaluating panitumumab plus best supportive care vs best supportive care in chemorefractory wild-type KRAS or RAS metastatic colorectal cancer

Background:We assessed the treatment effect of panitumumab plus best supportive care (BSC) vs BSC on overall survival (OS) in patients with chemorefractory wild-type KRAS exon 2 metastatic colorectal cancer (mCRC) and report the first prospective extended RAS analysis in a phase 3 trial.Methods:Patients with wild-type KRAS exon 2 mCRC were randomised 1 : 1 to panitumumab (6 mg kg−1 Q2W) plus BSC or BSC. On-study crossover was prohibited. RAS mutation status was determined by central laboratory testing. The primary endpoint was OS in wild-type KRAS exon 2 mCRC; OS in wild-type RAS mCRC (KRAS and NRAS exons 2, 3, and 4) was a secondary endpoint.Results:Three hundred seventy seven patients with wild-type KRAS exon 2 mCRC were randomised. Median OS was 10.0 months with panitumumab plus BSC vs 7.4 months with BSC (HR=0.73; 95% CI=0.57–0.93; P=0.0096). RAS ascertainment was 86%. In wild-type RAS mCRC, median OS for panitumumab plus BSC was 10.0 vs 6.9 months for BSC (HR=0.70; 95% CI=0.53–0.93; P=0.0135). Patients with RAS mutations did not benefit from panitumumab (OS HR=0.99; 95% CI=0.49–2.00). No new safety signals were observed.Conclusions:Panitumumab significantly improved OS in wild-type KRAS exon 2 mCRC. The effect was more pronounced in wild-type RAS mCRC, validating previous retrospective analyses.

Persistent prevention of oxaliplatin-induced peripheral neuropathy using calmangafodipir (PledOx®): a placebo-controlled randomised phase II study (PLIANT)

Abstract Purpose: Oxaliplatin causes disabling acute and chronic peripheral neuropathy. We explored the preventive effects of calmangafodipir, mimicking the mitochondrial enzyme manganese superoxide dismutase, thereby protecting cells from oxidative stress, in a placebo-controlled, double-blinded randomised phase II study (ClinicalTrials.gov.NCT01619423) in patients with metastatic colorectal cancer (mCRC). Patient and methods: mCRC patients treated with modified FOLFOX-6 (folinic acid 200 mg/m2, 5-fluorouracil bolus 400 mg/m2, oxaliplatin 85 mg/m2 and 5-fluorouracil 2400 mg/m2 continuous infusion for 46 h) every fortnight for 8 cycles in first or second line were eligible. Calmangafodipir was given in a phase I dose-finding and in a phase II placebo-controlled study, as a 5-min infusion 10 min prior to oxaliplatin. Neurotoxicity was evaluated by the physician using the Oxaliplatin Sanofi Specific Scale and by the patient using the cold allodynia test and the Leonard scale. Results: Eleven patients were included in phase I without any detectable toxicity to calmangafodipir. In the phase II study, 173 patients were randomised to placebo (n = 60), calmangafodipir 2 µmol/kg (n = 57) and calmangafodipir 5 µmol/kg (n = 45, initially 10 µmol/kg, n = 11). Calmangafodipir-treated patients (all three doses pooled) had less physician graded neurotoxicity (odds ratio (90% confidence interval one-sided upper level) 0.62(1.15), p = .16), significantly less problems with cold allodynia (mean 1.6 versus 2.3, p < .05) and significantly fewer sensory symptoms in the Leonard scale (cycle 1–8 mean 1.9 versus 3.0, p < .05 and during follow-up after 3 and 6 months, mean 3.5 versus 7.3, p < .01). Response rate, progression-free and overall survival did not differ among groups. Conclusions: Calmangafodipir at a dose of 5 µmol/kg appears to prevent the development of oxaliplatin-induced acute and delayed CIPN without apparent influence on tumour outcomes.

Efficacy and safety of bevacizumab in combination with oxaliplatin, irinotecan and fluoropyrimidine-based therapy in advanced colorectal cancer

Methods: This was a controlled, prospective, multicentre, cohort study. Thirty patients with advanced colorectal cancer were enrolled into this study. Bevacizumab was applied with oxaliplatin-, irinotecan-, 5FU- or capecitabine -based chemotherapy in the first-, second- or third-therapy lines. Totally 261 cycles were applied. The median number of applied cycles per patient was 8 (range 2-16). Results: Objective tumor response (RR) was seen in 11 patients 37% (95%CI 19-69%) calculated on an intention-to-treat basis. The median duration of response was 12 months. Three of 11 patients (27%) with PR had secondary surgery. RR was seen in 9 of 16 patients (56%) who received bevacizumab in the first-line treatment and in 2 of 14 patients (14%) who received therapy in the second+ lines (p=0.02). Clinical benefit (PR+SD) was seen in 22 (74%) patients. 75% of patients achieved clinical benefit in the first-line and 74% in the second+ chemotherapy lines. The median time to progression (TTP) of the patients is was 9 + months (95%CI 7 - + ∞) at the moment of this analysis. The median TTP of patients who received bevacizumab in the first line was 11 months (95%CI 8 - + ∞). The median TTP of patients who received bevacizumab in the second+ lines was 5.5 months (95%CI 4 - + ∞) (p=0.015). The median survival time (OS) for all patients was 9 + months (95%CI 7 - + ∞). The median OS at the moment of analysis was 11 months (95%CI 9 - + ∞) for patients receiving bevaci- zumab in the first line, and 7 months for patients receiving the drug in the second+ lines (95%CI 6 - + ∞) (p=0.024). The incidence of any toxicity grade 3-4 was less than 10%. Bevacizumab associated incidence of grade 3-4 side effects did not exceed 5%. Hypertension 5% and thromboembolism 5% were the most frequent events. Gastrointestinal perforation did not occur. There was one toxic death due to sepsis and not directly associated with bevacizumab toxicity. Conclusion: Bevacizumab can safely be added to different chemotherapeutic regimens in first- and second+ line. The con- ferred benefit in overall survival, TTP and response rate obviously requires randomized trials.

Phase I/II trial of pimasertib plus gemcitabine in patients with metastatic pancreatic cancer: Pimasertib plus gemcitabine in pancreatic cancer

The selective MEK1/2 inhibitor pimasertib has shown anti‐tumour activity in a pancreatic tumour model. This phase I/II, two‐part trial was conducted in patients with metastatic pancreatic adenocarcinoma (mPaCa) (NCT01016483). In the phase I part, oral pimasertib was given once daily discontinuously (5 days on/2 days off treatment) or twice daily continuously (n = 53) combined with weekly gemcitabine (1,000 mg/m2) in 28‐day cycles to identify the recommended phase II dose (RP2D) of pimasertib. In the phase II part, patients were randomised to pimasertib (RP2D) or placebo plus weekly gemcitabine (n = 88) to investigate progression‐free survival (PFS), overall survival (OS) and safety. The RP2D was determined to be 60 mg BID. PFS and OS outcomes did not indicate any treatment benefit for pimasertib over placebo in combination with gemcitabine (median PFS 3.7 and 2.8 months, respectively, HR = 0.91, 95% CI: 0.58–1.42: median OS 7.3 vs. 7.6 months, respectively). KRAS status did not influence PFS or OS. The incidence of grade ≥3 adverse events was 91.1% and 85.7% for pimasertib/gemcitabine and placebo/gemcitabine respectively, but there was a higher incidence of ocular events with pimasertib/gemcitabine (28.9% vs. 4.8% for placebo/gemcitabine). In conclusion, no clinical benefit was observed with first‐line pimasertib plus gemcitabine compared with gemcitabine alone in patients with mPaCa.

Clamp-crushing vs. radiofrequency-assisted liver resection:changes in liver function tests.

BACKGROUND/AIMS Liver resection is the gold standard in managing patients with metastatic or primary liver cancer. The aim of our study was to compare the traditional clamp-crushing technique to the radiofrequency- assisted liver resection technique in terms of postoperative liver function. METHODOLOGY Liver function was evaluated preoperatively and on postoperative days 3 and 7. Liver synthetic function parameters (serum albumin level, prothrombin time and international normalized ratio), markers of hepatic injury and necrosis (serum alanine aminotransferase, aspartate aminotransferase and total bilirubin level) and microsomal activity (quantitative lidocaine test) were compared. RESULTS Forty three patients completed the study (14 had clamp-crushing and 29 had radiofrequency assisted liver resection). The groups did not differ in demographic characteristics, pre-operative liver function, operative time and perioperative transfusion rate. In postoperative period, there were similar changes in monitored parameters in both groups except albumin levels, that were higher in radiofrequency-assisted liver resection group (p=0.047). CONCLUSIONS Both, traditional clamp-crushing technique and radiofrequency assisted liver resection technique, result in similar postoperative changes of most monitored liver function parameters.

Final Analysis of Outcomes and RAS/BRAF Status in a Randomized Phase 3 Study of Panitumumab and Best Supportive Care in Chemorefractory Wild Type KRAS Metastatic Colorectal Cancer

Micro‐Abstract: Tumor rat sarcoma gene (RAS) status is a negative anti‐epidermal growth factor receptor therapy biomarker in metastatic colorectal cancer (mCRC). Early tumor shrinkage (ETS) and depth of response (DpR) were evaluated for 270 patients with RAS wild type mCRC randomized to best supportive care with or without panitumumab (6.0 mg/kg, intravenously, on day 1 of 14‐day cycles). Panitumumab improved outcomes, and ETS and DpR might be useful efficacy markers. Introduction: Tumor rat sarcoma gene (RAS) status is a negative predictive biomarker for anti‐epidermal growth factor receptor (EGFR) therapy in metastatic colorectal cancer (mCRC). We analyzed outcomes according to RAS and v‐Raf murine sarcoma viral oncogene homolog B (BRAF) mutational status, and evaluated early tumor shrinkage (ETS) and depth of response (DpR) for patients with wild type RAS. Patients and Methods: Patients with confirmed metastatic colon or rectum adenocarcinoma, wild type Kristen rat sarcoma gene tumor exon 2 status, clinical/radiologic disease progression or toxicity during irinotecan or oxaliplatin treatment, and no previous anti‐EGFR therapy were randomized 1:1 to receive best supportive care (BSC) with or without panitumumab (6.0 mg/kg, intravenously, on day 1 of each 14‐day cycle) in this open‐label, multicenter, phase III study (20100007). RAS and BRAF mutation status were determined using Sanger sequencing. ETS was evaluated as maximum percentage change from baseline to week 8; DpR was calculated as the percentage change for tumor shrinkage at nadir versus baseline. Results: Overall, 270 patients had RAS wild type mCRC (panitumumab with BSC, n = 142; BSC, n = 128). For patients with wild type RAS tumors, median overall survival (OS; hazard ratio [HR], 0.72; P = .015) and progression‐free survival (PFS; HR, 0.45; P < .0001) were improved with panitumumab with BSC versus BSC. Similar improvements were seen for patients with wild type RAS, and wild type BRAF tumors (OS: HR, 0.75; P = .04; PFS: HR, 0.45; P < .0001). Median DpR was 16.9% for the evaluable panitumumab with BSC wild type RAS population. Overall, 69.5% experienced any type of tumor shrinkage at week 8; 38.2% experienced ≥ 20% shrinkage. Similar improvements in OS and PFS were seen with stratification according to ETS. Conclusion: This analysis showed that panitumumab improved outcomes in wild type RAS mCRC and indicated that ETS and DpR could be used as additional efficacy markers.