Updated results from MONALEESA-2, a phase III trial of first-line ribociclib plus letrozole versus placebo plus letrozole in hormone receptor-positive, HER2-negative advanced breast cancer.

Background: The phase III MONALEESA-2 study demonstrated significantly prolonged progression-free survival (PFS) and a manageable toxicity profile for first-line ribociclib plus letrozole versus placebo plus letrozole in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer. Here, we report updated efficacy and safety data, together with exploratory biomarker analyses, from the MONALEESA-2 study. Patients and methods: A total of 668 postmenopausal women with HR+, HER2- recurrent/metastatic breast cancer were randomized (1 : 1; stratified by presence/absence of liver and/or lung metastases) to ribociclib (600 mg/day; 3-weeks-on/1-week-off; 28-day treatment cycles) plus letrozole (2.5 mg/day; continuous) or placebo plus letrozole. The primary end point was locally assessed PFS. The key secondary end point was overall survival (OS). Other secondary end points included overall response rate (ORR) and safety. Biomarker analysis was an exploratory end point. Results: At the time of the second interim analysis, the median duration of follow-up was 26.4 months. Median PFS was 25.3 months [95% confidence interval (CI) 23.0-30.3] for ribociclib plus letrozole and 16.0 months (95% CI 13.4-18.2) for placebo plus letrozole (hazard ratio 0.568; 95% CI 0.457-0.704; log-rank P = 9.63 × 10-8). Ribociclib treatment benefit was maintained irrespective of PIK3CA or TP53 mutation status, total Rb, Ki67, or p16 protein expression, and CDKN2A, CCND1, or ESR1 mRNA levels. Ribociclib benefit was more pronounced in patients with wild-type versus altered receptor tyrosine kinase genes. OS data remain immature, with 116 deaths observed; 50 in the ribociclib arm and 66 in the placebo arm (hazard ratio 0.746; 95% CI 0.517-1.078). The ORR was 42.5% versus 28.7% for all patients treated with ribociclib plus letrozole versus placebo plus letrozole, respectively, and 54.5% versus 38.8%, respectively, for patients with measurable disease. Safety results, after a further 11.1 months of follow-up, were comparable with those reported at the first analysis, with no new or unexpected toxicities observed, and no evidence of cumulative toxicity. Conclusions: The improved efficacy outcomes and manageable tolerability observed with first-line ribociclib plus letrozole are maintained with longer follow-up, relative to letrozole monotherapy. Clinical trials number: NCT01958021.

Long-duration, weekly treatment with gemcitabine plus vinorelbine for non-small cell lung cancer: a multicenter phase II study.

In this phase II study, gemcitabine and vinorelbine were combined at suboptimal doses for weekly administration in advanced non-small cell lung cancer (NSCLC). The primary objectives were to determine objective response rate (ORR) and time to progression (TTP). Secondary endpoints were safety and overall survival. Chemonaive patients with histologically or cytologically confirmed stage IIIB or IV NSCLC received vinorelbine (25 mg/m2) immediately followed by gemcitabine (800 mg/m2) once each week (on day 1) for 6 months without rest. From May 1998 to May 1999, 40 patients were enrolled (85% males; 70% stage IV) with a median age of 65.5. A total of 478 doses were administered, with a median of 9 per patient (range 2-72). The ORR was 27.5% (95% CI, 15.1-44.1%). The median TTP was 3.5 months (95% CI, 2.9-4.4 months). At a median follow-up of 6.5 months, the median survival was 11.6 months, and survival rates at 1 and 2 year(s) were 47.5% and 15.8%, respectively. The most common grade 3/4 hematologic toxicity was neutropenia, in 70% of patients, with febrile neutropenia in 28%. The most common grade 3/4 non-hematologic toxicity was transaminase elevation, in 22.5% of patients, which was transient and reversible. The other most prominent toxicities were, unexpectedly, pulmonary and cardiac toxicities. Based on these results, weekly, long-term administration of gemcitabine-vinorelbine appears to be an active regimen in NSCLC that warrants further investigation.

Multicentre phase II study and pharmacokinetic analysis of irinotecan in chemotherapy-naïve patients with glioblastoma.

BACKGROUND: To assess the antitumour activity and safety profile of irinotecan and its pharmacokinetic interactions with anticonvulsants in patients with glioblastoma multiforme. PATIENTS AND METHODS: This multicentre phase II and pharmacokinetic study investigated the effects of irinotecan 350 mg/m(2) given as a 90-min infusion every 3 weeks either prior to (group A) or after relapse following radiotherapy (group B) in chemotherapy-naïve patients with glioblastoma. Preferred concomitant medication for seizure prevention was valproic acid. Pharmacokinetic analysis of irinotecan and its main metabolites (SN-38, SN-38-G, APC and NPC) was performed during cycle 1. An independent panel of experts reviewed the activity data. RESULTS: Fifty-two patients (25 patients in group A and 27 patients in group B) received a total of 191 cycles of irinotecan. Forty-six patients (22 patients in group A and 24 patients in group B) were evaluable and externally reviewed for activity. According to external review, one partial response (group B), seven minor responses (three in group A and four in group B), 12 disease stabilisations (seven in group A and five in group B) were observed. This resulted in an overall response rate of only 2.2% (95% confidence interval 0.2% to 6.5%). The median time to tumour progression was 9 weeks in group A and 14.4 weeks in group B. Six-month progression-free survival rates were 26% in group A and 43% in group B. Grade 3-4 toxicities (percentage of patients in groups A and B) consisted of neutropenia (12.5% and 25.9%), diarrhoea (8.3% and 7.4%), asthenia (12.5% and 7.4%) and vomiting (0% and 7.4%). The clearance of irinotecan was 12.4 and 14.4 l/h/m(2) in two patients who received no anticonvulsant. In patients receiving valproic acid, the clearance of irinotecan was 17.2 +/- 4.4 l/h/m(2). CONCLUSIONS: Irinotecan given at the dose of 350 mg/m(2) every 3 weeks has limited clinical activity as a single agent in patients with newly diagnosed and recurrent glioblastoma after radiotherapy. The toxicity profile and plasma disposition of irinotecan and SN-38 were not strongly influenced by anticonvulsant valproic acid therapy. Although the response rate of irinotecan as a single agent was limited, it remains an attractive drug for combination studies in patients with glioblastoma.

Randomized multicenter phase II study comparing a combination of fluorouracil and folinic acid and alternating irinotecan and oxaliplatin with oxaliplatin and irinotecan in fluorouracil-pretreated metastatic colorectal cancer patients.

PURPOSE: To assess antitumor activity and safety of two regimens in advanced colorectal cancer (CRC) patients with proven fluorouracil (5-FU) resistance in a randomized phase II study: 5-FU/folinic acid (FA) combined with alternating irinotecan (also called CPT-11) and oxaliplatin (FC/FO tritherapy), and an oxaliplatin/irinotecan (OC) combination. PATIENTS AND METHODS: Sixty-two patients were treated: arm FC/FO (32 patients) received, every 4 weeks, FA 200 mg/m(2) followed by a 400-mg/m(2) 5-FU bolus injection, then a 600-mg/m(2) continuous infusion of 5-FU on days 1 and 2 every 2 weeks administered alternately with irinotecan (180 mg/m(2) on day 1) and oxaliplatin (85 mg/m(2) on day 15). Arm OC (30 patients) received oxaliplatin 85 mg/m(2) and irinotecan 200 mg/m(2) every 3 weeks. RESULTS: In an intent-to-treat analysis, two partial responses lasting 10.7 and 16 months were observed with the tritherapy regimen, and seven (median duration, 11 months; range, 10.6 to 11.4 months) were observed with the bitherapy regimen. Median progression-free and overall survival times were 8.2 and 9.8 months, respectively, in the FC/FO arm and 8.5 and 12.3 months, respectively, in the OC arm. Main grade 3/4 toxicities were, respectively, neutropenia, 53% and 47%; febrile neutropenia, 13% and 3%; diarrhea, 19% and 10%; vomiting, 6% and 13%; and neurosensory toxicity, 3% and 3%. No treatment-related deaths occurred. CONCLUSION: The every-3-weeks OC combination is safe and active in advanced 5-FU-resistant CRC patients. The lower activity data seen with the tritherapy regimen may be related to the lower dose intensities of irinotecan and oxaliplatin in this schedule.