Alicia Clawson

Significantly Longer Progression-Free Survival With nab-Paclitaxel Compared With Docetaxel As First-Line Therapy for Metastatic Breast Cancer

PURPOSE In patients with metastatic breast cancer (MBC), nab-paclitaxel produced significantly higher antitumor activity compared with patients who received solvent-based paclitaxel. This phase II study examined the antitumor activity and safety of weekly and every 3 week (q3w) nab-paclitaxel compared with docetaxel as first-line treatment in patients with MBC. PATIENTS AND METHODS In this randomized, multicenter study, patients (N = 302) with previously untreated MBC received nab-paclitaxel 300 mg/m(2) q3w, 100 mg/m(2) weekly, or 150 mg/m(2) weekly or docetaxel 100 mg/m(2) q3w. RESULTS nab-Paclitaxel 150 mg/m(2) weekly demonstrated significantly longer progression-free survival (PFS) than docetaxel by both independent radiologist assessment (12.9 v 7.5 months, respectively; P = .0065) and investigator assessment (14.6 v 7.8 months, respectively; P = .012). On the basis of independent radiologist review, both 150 mg/m(2) (49%) and 100 mg/m(2) (45%) weekly of nab-paclitaxel demonstrated a higher overall response rate (ORR) than docetaxel (35%), but this did not reach statistical significance. This trend was supported by statistically significant investigator ORR for both weekly nab-paclitaxel doses versus docetaxel. nab-Paclitaxel q3w versus docetaxel was not different for PFS or ORR. On the basis of both the independent radiologist and investigator review, disease control rate was significantly higher for patients receiving either dose of weekly nab-paclitaxel compared with docetaxel. Grade 3 or 4 fatigue, neutropenia, and febrile neutropenia were less frequent in all nab-paclitaxel arms. The frequency and grade of peripheral neuropathy were similar in all arms. CONCLUSION This randomized study in first-line MBC demonstrated superior efficacy and safety of weekly nab-paclitaxel compared with docetaxel, with a statistically and clinically significant prolongation of PFS (> 5 months) in patients receiving nab-paclitaxel 150 mg/m(2) weekly compared with docetaxel 100 mg/m(2) q3w.

Phase II Study of Weekly Albumin-Bound Paclitaxel for Patients with Metastatic Breast Cancer Heavily Pretreated with Taxanes

PURPOSE Nanoparticle albumin-bound paclitaxel, a solvent-free, albumin-bound paclitaxel, demonstrated antitumor activity in patients with taxane-naive metastatic breast cancer (MBC). We examined albumin-bound paclitaxel (100 mg/m2 or 125 mg/m2 administered weekly) to determine the antitumor activity in patients with MBC whose disease progressed despite conventional taxane therapy. PATIENTS AND METHODS Women with MBC that was previously treated with taxanes were eligible for participation. Taxane failure was defined as metastatic disease progression during taxane therapy or relapse within 12 months of adjuvant taxane therapy. Primary objectives were response rates (RRs) and the safety/tolerability of albumin-bound paclitaxel. RESULTS Women were treated with albumin-bound paclitaxel 100 mg/m2 (n = 106) or 125 mg/m2 (n = 75) on days 1, 8, and 15 of a 28-day cycle. Response rates were 14% and 16% for the 100-mg/m2 and 125-mg/m2 cohorts, respectively; an additional 12% and 21% of patients, respectively, had stable disease (SD) > or = 16 weeks. Median progression-free survival times were 3 months at 100 mg/m2 and 3.5 months at 125 mg/m2; median survival times were 9.2 months and 9.1 months, respectively. Survival was similar for responding patients and those with SD. No severe hypersensitivity reactions were reported. Patients who developed treatment-limiting peripheral neuropathy typically could be restarted on a reduced dose of albumin-bound paclitaxel after a 1-2-week delay. Grade 4 neutropenia occurred in < 5% of patients. CONCLUSION Albumin-bound paclitaxel 100 mg/m2 given weekly demonstrated the same antitumor activity as albumin-bound paclitaxel 125 mg/m2 weekly and a more favorable safety profile in patients with MBC that had progressed with previous taxane therapy. Survival of patients with SD > or = 16 weeks was similar to that of responders.

Phase II Trial of Nab-Paclitaxel Compared With Docetaxel as First-Line Chemotherapy in Patients With Metastatic Breast Cancer: Final Analysis of Overall Survival

BACKGROUND A randomized phase II study in first-line MBC demonstrated superior efficacy and safety of weekly nab-paclitaxel compared with docetaxel. Final survival analyses and updated safety results are reported. PATIENTS AND METHODS Three hundred two patients with no previous chemotherapy for MBC were randomized to receive nab-paclitaxel 300 mg/m(2) q3w, nab-paclitaxel 100 mg/m(2) or 150 mg/m(2) the first 3 of 4 weeks (qw 3/4), or docetaxel 100 mg/m(2) q3w. The trial was powered for analyses of antitumor activity and safety. RESULTS Treatment with nab-paclitaxel 150 mg/m(2) qw 3/4 resulted in a median overall survival (OS) of 33.8 months compared with 22.2, 27.7, and 26.6 months for nab-paclitaxel 100 mg/m(2) qw 3/4, nab-paclitaxel 300 mg/m(2) q3w, and docetaxel, respectively (overall P = .047). Patients receiving 150 mg/m(2)nab-paclitaxel had prolonged median OS compared with those in the 100 mg/m(2)nab-paclitaxel arm (hazard ratio, 0.575; P = .008). A trend toward a longer OS was noted in the 150 mg/m(2)nab-paclitaxel arm versus docetaxel arm (hazard ratio, 0.688). Grade 3 or 4 fatigue, neutropenia, and febrile neutropenia were less frequent in all nab-paclitaxel arms compared with docetaxel. CONCLUSIONS Consistent with previously published efficacy results, these data suggest that 150 mg/m(2) qw 3/4 may represent the most clinically efficacious nab-paclitaxel dosing regimen for patients with no previous chemotherapy for MBC. A phase III trial confirming these results would be necessary and prudent before widespread adoption of the 150 mg/m(2) dose in clinical practice.

Phase II Trial of Weekly Nanoparticle Albumin-Bound Paclitaxel With Carboplatin and Trastuzumab as First-line Therapy for Women With HER2-Overexpressing Metastatic Breast Cancer

PURPOSE This multicenter phase II trial evaluated the efficacy and safety of weekly nanoparticle albumin-bound paclitaxel with carboplatin and weekly trastuzumab as first-line therapy for women with HER2-overexpressing metastatic breast cancer (MBC). PATIENTS AND METHODS We treated 32 patients who had measurable MBC that was HER2-positive defined by an immunohistochemical staining score of 3+ or gene amplification by fluorescence in situ hybridization, required for those with an IHC of 2+. Patients were treated with albumin-bound paclitaxel 100 mg/m2 and carboplatin at area under the curve (AUC) = 2 on days 1, 8, and 15 of a 28-day cycle. Trastuzumab was administered at 2 mg/kg weekly after a loading dose of 4 mg/kg. Because of hypersensitivity reactions occurring during carboplatin infusion numbers 6-8 in 4 of the first 13 patients with this premedication-free regimen, the protocol was amended for carboplatin and dosed at AUC = 6 day 1 each 28-day cycle, in lieu of introducing steroid prophylaxis. Patients were treated with 6 cycles and allowed to continue with all 3 drugs or trastuzumab alone if free of progression and unacceptable toxicity after 6 cycles. RESULTS The overall response rate (ORR) was 62.5% (95% CI, 45.7%-79.3%) with 3 confirmed complete responders (CRs; 9%) and 17 confirmed partial responses (PRs; 53%). An additional 6 patients (19%) had stable disease (SD) for greater than 16 weeks for a clinical benefit rate (ORR + SD > 16 weeks) of 81%. As of April 16, 2009, 20 patients (63%) had progressed with a median progression-free survival (PFS) of 16.6 months (95% CI, 7.5-26.5 months). Antitumor activity was similar for patients treated with weekly carboplatin and every-4-week carboplatin (ORR, 65% vs. 67%, respectively). Hematologic toxicities were the only grade 4 toxicities noted and were infrequent with grade 4 neutropenia in 3 patients (9%) and 1 febrile neutropenia. Grade 2/3 peripheral neuropathy was uncommon (13%/3%). CONCLUSION Weekly albumin-bound paclitaxel with carboplatin and trastuzumab is highly active in HER2-overexpressing MBC. In the absence of corticosteroid premedication, which we avoided with albumin-bound paclitaxel, carboplatin seems best dosed every 4 weeks rather than weekly because of carboplatin-associated hypersensitivity reactions. The regimen was very well tolerated with few grade 3 and 4 nonhematologic toxicities experienced, and severe hematologic toxicity and peripheral neuropathy were infrequent.

Randomized Phase II Trial of Weekly vs. Every 2 Weeks vs. Every 3 Weeks Nanoparticle Albumin- Bound Paclitaxel With Bevacizumab as First-Line Chemotherapy for Metastatic Breast Cancer

BACKGROUND Nanoparticle albumin-bound paclitaxel (nab-P) and bevacizumab have each demonstrated efficacy in patients with MBC. This trial was designed to further develop nab-P by evaluating its efficacy and safety using every 3 weeks (q3w), every 2 weeks (q2w), or weekly scheduling in combination with bevacizumab as first-line treatment of MBC. PATIENTS AND METHODS This open-label phase II study randomized patients to nab-P 260 mg/m(2) q3w (arm A) vs. 260 mg/m(2) q2w with filgrastim (arm B) vs. 130 mg/m(2) weekly uninterrupted, all with bevacizumab (15 mg/kg q3w arm A, 10 mg/kg q2w arms B and C). The primary endpoints were overall response rate (ORR) and toxicity. Time to tumor progression (TTP) and overall survival were secondary endpoints. RESULTS Of 212 patients randomized, 208 (arm A, 75; arm B, 54; arm C, 79) were treated. Arm B was closed early due to toxicity, with more grade ≥ 2 fatigue (arm A, 46%; arm B, 62%; arm C, 62%) and bone pain (arm A, 11%; arm B, 23%; arm C, 5%). Neurotoxicity grade ≥ 2 was equivalent across the arms (> 50%) and reversible for most patients. Febrile neutropenia occurred in ≤ 3% of patients in all arms. ORR was similar among the arms (arm A, 45%; arm B, 41%; arm C, 46%). Median TTP was slightly longer in arm C (9.0 months) vs. arms A (8.0 months) and B (5.8 months) (overall, P = .105). CONCLUSIONS Significant antitumor activity was observed in all the arms. Weekly nab-P with bevacizumab appeared to have the highest therapeutic index. However, sensory neuropathy was treatment limiting, which suggests that a 3 weeks on and 1 week off schedule should be explored.

PRELIMINARY EVIDENCE OF A MOLECULAR PREDICTOR OF TAZEMETOSTAT RESPONSE, BEYOND EZH2 MUTATION, IN NHL PATIENTS VIA CHARACTERIZATION OF ARCHIVE TUMOR AND CIRCULATING TUMOR DNA

Introduction: EZH2, a histone methyl transferase subunit of Polycomb repressor complex 2, is frequently mutated in DLBL. Inhibitors of EZH2 have demonstrated promising responses in early clinical trials. We examined the frequency of EZH2 mutation in 2 large prospective series of DLBL and correlated this to clinical outcomes in relation to other biological features. Methods: Patients (pts) received standard immunochemotherapy regimens as first‐line treatment for DLBL. Sanger sequencing (SS) focusing on “hotspot” mutation sites in exons 16 and 18 was successful in 1052 of 1097 DLBL samples enrolled in the UK NCRI Molecular Profiling for Lymphoma (MaPLe) study. Next generation sequencing (NGS) using Fluidigm Access Array PCR and Illumina MiSeq was used to profile a separate cohort of 365 pts enrolled in the UK NCRI/ SAKK REMoDL‐B trial (NCT01324596) (CRUKE/10/024). In these cases, cell of origin (COO) was determined by gene expression profiling (GEP) using Illumina WG‐DASL. Results: EZH2 mutations were detected in 9% of DLBL pts (98/1052) by SS and 15% (54/365) by NGS. Ninety‐five percent of mutations were at Y646 position in exon 16. EZH2mutations were strongly associated with GCB subtype, occurring in 27% of cases (50/185) versus 0/ 106 in ABC subtype and (4/71) in unclassified subtype (P < .0001). Overall, EZH2 mutations were not significantly associated with age, sex, performance status, stage, or IPI, compared to unmutated GCB DLBL. PFS was similar between EZH2 mutated and unmutated GCB DLBL subtype: 78.5% vs 80.7% at 30 months, HR 1.06 (95% CI, 0.62‐1.81) (P = .844). A subset of GCB cases showed Burkitt‐like GEP, associated with inferior progression free survival (PFS) HR 2.21 (95% CI, 1.28‐7.73) (P = .012), among which 11/24, where mutation status was available, had EZH2 mutations. There was heterogeneity in progression free survival identified by presence or absence of EZH2 mutations and Burkitt‐like gene expression signature. Conclusions: EZH2 mutations are significantly associated with the DLBL GCB‐subtype and more common in cases identified as Burkitt‐ like by GEP. Overall outcomes are similar in mutant and wild‐type cases when adjusted for COO and IPI, but Burkitt‐like cases that carry EZH2 mutations may be a preferential subset in which to test targeted therapies.