Randomized Trial of Irinotecan and Cetuximab With or Without Vemurafenib in BRAF-Mutant Metastatic Colorectal Cancer (SWOG S1406).

PURPOSE: BRAFV600E mutations are rarely associated with objective responses to the BRAF inhibitor vemurafenib in patients with metastatic colorectal cancer (CRC). Blockade of BRAFV600E by vemurafenib causes feedback upregulation of EGFR, whose signaling activities can be impeded by cetuximab. METHODS: One hundred six patients with BRAFV600E-mutated metastatic CRC previously treated with one or two regimens were randomly assigned to irinotecan and cetuximab with or without vemurafenib (960 mg PO twice daily). RESULTS: Progression-free survival, the primary end point, was improved with the addition of vemurafenib (hazard ratio, 0.50, P = .001). The response rate was 17% versus 4% (P = .05), with a disease control rate of 65% versus 21% (P < .001). A decline in circulating tumor DNA BRAFV600E variant allele frequency was seen in 87% versus 0% of patients (P < .001), with a low incidence of acquired RAS alterations at the time of progression. RNA profiling suggested that treatment benefit did not depend on previously established BRAF subgroups or the consensus molecular subtype. CONCLUSION: Simultaneous inhibition of EGFR and BRAF combined with irinotecan is effective in BRAFV600E-mutated CRC.

Randomised phase II trial (SWOG S1310) of single agent MEK inhibitor trametinib Versus 5-fluorouracil or capecitabine in refractory advanced biliary cancer.

BACKGROUND: The rationale for the evaluation of trametinib in advanced biliary cancer (BC) is based on the presence of mitogen-activated protein kinase alterations and on earlier promising results with MEK inhibitors in BC. METHODS: Patients with histologically proven BC who progressed on gemcitabine/platinum were randomised to trametinib daily (arm 1) versus fluoropyrimidine therapy (infusional 5-fluorouracil or oral capecitabine, arm 2). The primary end-point was overall survival (OS). Secondary end-points included progression free survival (PFS) and response rate. A planned interim futility analysis of objective response was performed on the first 14 patients registered to the trametinib arm. RESULTS: The study was stopped early based on the lack of measurable response in the trametinib arm. A total of 44 eligible patients were randomised (24 patients in arm 1 and 20 patients in arm 2). Median age was 62 years and the primary sites of tumour were cholangiocarcinoma (68%) and gallbladder (32%). The overall response rate was 8% (95% CI 0%-19%) in arm 1 versus 10% (95% CI 0%-23%) in arm 2 (p > .99) Median OS was 4.3 months for arm 1 and 6.6 months for arm 2. The median PFS was 1.4 months for arm 1 and 3.3 months for arm 2. CONCLUSIONS: This is the first prospective randomised study of a targeted agent versus chemotherapy for the second-line treatment of BC. In this unselected population, the interim analysis result of unlikely benefit with trametinib resulted in early closure.

Association of immunophenotype with expression of topoisomerase II α and ß in adult acute myeloid leukemia.

Anthracyclines used in the treatment of acute myelogenous leukemia (AML) inhibit the activity of the mammalian topoisomerase II (topo II) isoforms, topo II α and topo IIß. In 230 patients with non-M3 AML who received frontline ara-C/daunorubicin we determined expression of topo IIα and topo IIß by RT-PCR and its relationship to immunophenotype (IP) and outcomes. Treatment outcomes were analyzed by logistic or Cox regression. In 211 patients, available for analysis, topo IIα expression was significantly lower than topo IIß (P < 0.0001). In contrast to topo IIα, topo IIß was significantly associated with blast percentage in marrow or blood (P = 0.0001), CD7 (P = 0.01), CD14 (P < 0.0001) and CD54 (P < 0.0001). Event free survival was worse for CD56-negative compared to CD56-high (HR = 1.9, 95% CI [1.0-3.5], p = 0.04), and overall survival was worse for CD-15 low as compared to CD15-high (HR = 2.2, 95% CI [1.1-4.2], p = 0.02). Ingenuity pathway analysis indicated topo IIß and immunophenotype markers in a network associated with cell-to-cell signaling, hematological system development/function and inflammatory response. Topo IIß expression reflects disease biology of highly proliferative disease and distinct IP but does not appear to be an independent variable influencing outcome in adult AML patients treated with anthracycline-based therapy.

Randomized, Phase II Study Prospectively Evaluating Treatment of Metastatic Esophageal, Gastric, or Gastroesophageal Cancer by Gene Expression of ERCC1: SWOG S1201.

PURPOSE: Platinum-based therapy is the standard of care in patients who have HER2-negative, advanced esophagogastric cancer (AEGC). Retrospective data suggest that intratumoral ERCC1 levels may determine platinum sensitivity. A randomized, phase II study was performed in patients with AEGC to explore whether the efficacy of a platinum-based therapy with fluorouracil, leucovorin, and oxaliplatin (FOLFOX) versus a non-platinum-containing regimen of irinotecan and docetaxel (IT) differed according to ERCC1 levels. PATIENTS AND METHODS: Overall, 202 untreated patients with HER2-negative AEGC and a Zubrod performance status of 0-1 were evaluated prospectively for mRNA expression of ERCC1 level and then randomly assigned to FOLFOX or IT, stratified by the intratumoral statuses of ERCC1 low (< 1.7) or high (≥ 1.7). Objectives were to assess progression-free survival (PFS) and overall survival (OS) in all patients treated with FOLFOX compared with IT, stratified by low and high ERCC1 levels, and to assess for interactive effects between ERCC1 expression and treatment arm. RESULTS: Eighty-six percent of patients had ERCC1 values < 1.7. Thus, evaluation of the ERCC1-high subgroup was limited. Grade ≥ 3 anemia, dehydration, diarrhea, and fatigue were greater in patients with IT. Occurrences of grade ≥ 3 neuropathy and decreased neutrophils were greater in patients with FOLFOX. In all patients, FOLFOX had a statistically superior median PFS compared with IT (5.7 v 2.9 months; hazard ratio, 0.68; P = .02). In patients with ERCC1 levels < 1.7 receiving FOLFOX, PFS and response rate were statistically superior to IT, with no significant difference in OS. CONCLUSION: The evaluation of ERCC1 in patients with upper GI tumors was thwarted by an overwhelming predominance of low ERCC1 mRNA expression. Nonetheless, distribution of treatment effects on PFS did not vary with expression. For all patients and for those with low ERCC1 expression, FOLFOX was superior in efficacy to IT.

Phase IB/II Randomized Study of FOLFIRINOX Plus Pegylated Recombinant Human Hyaluronidase Versus FOLFIRINOX Alone in Patients With Metastatic Pancreatic Adenocarcinoma: SWOG S1313.

PURPOSE: Pegylated recombinant human hyaluronidase (PEGPH20) degrades hyaluronan (HA) and, in combination with chemotherapy, prolongs survival in preclinical models. The activity of PEGPH20 with modified fluorouracil, leucovorin, irinotecan, and oxaliplatin (mFOLFIRINOX) was evaluated in patients with metastatic pancreatic cancer (mPC). MATERIALS AND METHODS: Patients had untreated mPC, a performance status of 0 to 1, and adequate organ function. Tumor HA status was not required for eligibility. After a phase Ib dose-finding study of mFOLFIRINOX plus PEGPH20, the phase II open-label study randomly assigned patients (1:1) to the combination arm or to mFOLFIRINOX alone (n = 138). The primary end point was overall survival (OS). RESULTS: PEGPH20 dosages of 3 µg/kg every 2 weeks were more tolerable than twice-weekly dosages used in the phase I study, so 3 µg/kg every 2 weeks was the phase II dosage. An amendment instituted enoxaparin prophylaxis in the PEGPH20 combination arm as a result of increased thromboembolic (TE) events. The planned interim futility analysis when 35 deaths (of 103 analyzable patients) occurred resulted in an OS hazard ratio (HR) of 2.07 that favored the control arm, and the study was closed to accrual. The treatment-related grade 3 to 4 toxicity was significantly increased in the PEGPH20 combination arm relative to control (odds ratio, 2.7; 95% CI, 1.1 to 7.1). The median OS in the mFOLFIRINOX arm was 14.4 months (95% CI, 10.1 to 15.7 months) versus 7.7 months (95% CI, 4.6 to 9.3 months) in the PEGPH20 combination arm. CONCLUSION: Addition of PEGPH20 to mFOLFIRINOX seems to be detrimental in patients unselected for tumor HA status. This combination caused increased toxicity (mostly GI and TE events) and resulted in decreased treatment duration compared with mFOLFIRINOX alone. The median OS in the mFOLFIRINOX control arm (14.4 months) is, to our knowledge, the longest yet reported and can be considered for patients with good PS.

Cetuximab Combined With Induction Oxaliplatin and Capecitabine, Followed by Neoadjuvant Chemoradiation for Locally Advanced Rectal Cancer: SWOG 0713.

BACKGROUND: Neoadjuvant chemoradiation (NCRT) is standard treatment for locally advanced rectal cancer. Pathologic complete response (pCR) has associated with improved survival. In modern phase III trials of NCRT, pCR ranges from 10% to 20%. Cetuximab improves response in KRAS (KRAS proto-oncogene) wild type (wt) metastatic colorectal cancer. S0713 was designed to assess improvement in pCR with additional use of cetuximab with induction chemotherapy and NCRT for locally advanced, KRAS-wt rectal cancer. PATIENTS AND METHODS: Patient eligibility: stage II to III biopsy-proven, KRAS-wt rectal adenocarcinoma; no bowel obstruction; adequate hematologic, hepatic and renal function; performance status of 0 to 2. Target enrollment: 80 patients. TREATMENT: induction chemotherapy with wCAPOX (weekly capecitabine and oxaliplatin) and cetuximab followed by the same regimen concurrent with radiation (omitting day 15 oxaliplatin). If fewer than 7 pCRs were observed at planned interim analysis after 40 patients received all therapy, the study would close. Eighty eligible patients would provide 90% power given a true pCR rate > 35% at a significance of 0.04. The regimen would lack future interest if pCR probability was ≤ 20%. RESULTS: Between February 2009 and April 2013, 83 patients registered. Four were ineligible and 4 not treated, leaving 75 evaluable for clinical outcomes and toxicity, of whom 65 had surgery. Of 75 patients, 20 had pCR (27%; 95% confidence interval [CI], 17%-38%); 19 (25%) had microscopic cancer; 36 (48%) had minor/no response (including 10 without surgery). Three-year disease-free survival was 73% (95% CI, 63%-83%). CONCLUSION: Our trial did not meet the pCR target of 35%. Toxicity was generally acceptable. This regimen cannot be recommended outside the clinical trial setting.

Phase III Prospective Randomized Comparison Trial of Depot Octreotide Plus Interferon Alfa-2b Versus Depot Octreotide Plus Bevacizumab in Patients With Advanced Carcinoid Tumors: SWOG S0518.

Purpose Treatment options for neuroendocrine tumors (NETs) remain limited. This trial assessed the progression-free survival (PFS) of bevacizumab or interferon alfa-2b (IFN-α-2b) added to octreotide among patients with advanced NETs. Patients and Methods Southwest Oncology Group (SWOG) S0518, a phase III study conducted in a US cooperative group system, enrolled patients with advanced grades 1 and 2 NETs with progressive disease or other poor prognostic features. Patients were randomly assigned to treatment with octreotide LAR 20 mg every 21 days with either bevacizumab 15 mg/kg every 21 days or 5 million units of IFN-α-2b three times per week. The primary end point was centrally assessed PFS. This trial is registered with ClinicalTrials.gov as NCT00569127. Results A total of 427 patients was enrolled, of whom 214 were allocated to bevacizumab and 213 to IFN-α-2b. The median PFS by central review was 16.6 months (95% CI, 12.9 to 19.6 months) in the bevacizumab arm and was 15.4 months (95% CI, 9.6 to 18.6 months) in the IFN arm (hazard ratio [HR], 0.93; 95% CI, 0.73 to 1.18; P = .55). By site review, the median PFS times were 15.4 months (95% CI, 12.6 to 17.2 months) for bevacizumab and 10.6 months (95% CI, 8.5 to 14.4 months) for interferon (HR, 0.90; 95% CI, 0.72 to 1.12; P = .33). Time to treatment failure was longer with bevacizumab than with IFN (HR, 0.72; 95% CI, 0.58 to 0.89; P = .003). Confirmed radiologic response rates were 12% (95% CI, 8% to 18%) for bevacizumab and 4% (95% CI, 2% to 8%) for IFN. Common adverse events with bevacizumab and octreotide included hypertension (32%), proteinuria (9%), and fatigue (7%); with IFN and octreotide, they included fatigue (27%), neutropenia (12%), and nausea (6%). Conclusion No significant differences in PFS were observed between the bevacizumab and IFN arms, which suggests that these agents have similar antitumor activity among patients with advanced NETs.

Effect of Selumetinib and MK-2206 vs Oxaliplatin and Fluorouracil in Patients With Metastatic Pancreatic Cancer After Prior Therapy: SWOG S1115 Study Randomized Clinical Trial.

IMPORTANCE: KRAS mutations are common in pancreatic cancer, but directly targeting the KRAS protein has thus far been unsuccessful. The aim of this trial was to block the MEK and PI3K/AKT pathways downstream of the KRAS protein as an alternate treatment strategy to slow cancer growth and prolong survival. This was the first cooperative group trial to evaluate this strategy using molecularly targeted oral combination therapy for the treatment of chemotherapy-refractory pancreatic cancer. OBJECTIVE: To compare selumetinib and MK-2206 vs modified FOLFOX (mFOLFOX) in patients with metastatic pancreatic cancer for whom gemcitabine-based therapy had failed. DESIGN, SETTING, AND PARTICIPANTS: SWOG S1115 was a randomized phase 2 clinical trial. Between September 2012 and May 2014, 137 patients with metastatic pancreatic adenocarcinoma for whom gemcitabine-based chemotherapy had failed were randomized to selumetinib plus MK-2206 or mFOLFOX. Patients were randomized in a 1:1 fashion and stratified according to duration of prior systemic therapy and presence of liver metastases. INTERVENTIONS: Patients received selumetinib 100 mg orally per day plus MK-2206 135 mg orally once per week or mFOLFOX (oxaliplatin, 85 mg/m2 intravenous, and fluorouracil, 2400 mg/m2 intravenous infusion over 46-48 hours) on days 1 and 15 of a 28-day cycle. MAIN OUTCOMES AND MEASURES: The primary end point of the study was overall survival. Secondary objectives included evaluating toxic effects, objective tumor response, and progression-free survival. RESULTS: There were 58 patients in the selumetinib plus MK-2206 (experimental) arm (60% male; median [range] age, 69 [54-88] years) and 62 patients in the mFOLFOX arm (35% male; median [range] age, 65 [34-82] years). In the experimental arm, median overall survival was shorter (3.9 vs 6.7 months; HR, 1.37; 95% CI, 0.90-2.08; P = .15), as was median progression-free survival (1.9 vs 2.0 months; HR, 1.61; 95% CI, 1.07-2.43; P = .02). One vs 5 patients had a partial response and 12 vs 14 patients had stable disease in the experimental arm vs mFOLFOX arm. Grade 3 or higher toxic effects were observed in 39 patients treated with selumetinib and MK-2206 vs 23 patients treated with mFOLFOX. More patients in the experimental arm discontinued therapy due to adverse events (13 vs 7 patients). CONCLUSIONS AND RELEVANCE: Dual targeting of the MEK and PI3K/AKT pathways downstream of KRAS by selumetinib plus MK-2206 did not improve overall survival in patients with metastatic pancreatic adenocarcinoma for whom gemcitabine-based chemotherapy had failed. This was the first randomized prospective evaluation of mFOLFOX in the US population that showed comparable results to CONKO-003 and PANCREOX. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01658943.

Phase 2 study of MK-2206, an allosteric inhibitor of AKT, as second-line therapy for advanced gastric and gastroesophageal junction cancer: A SWOG cooperative group trial (S1005).

BACKGROUND: The AKT inhibitor MK-2206 at a dose of 60 mg every other day was evaluated in gastric/gastroesophageal junction cancers. METHODS: Patients who had progressed after first-line treatment were eligible. Pertinent eligibility criteria included adequate organ function, a fasting serum glucose level ≤ 150 mg/dL, and less than grade 2 malabsorption or chronic diarrhea. MK-2206 was given orally (60 evaluable patients required). The primary endpoint was overall survival, and a median survival of 6.5 months (power, 89%; significance level, 0.07) was considered encouraging for further investigation. RESULTS: Seventy patients were included in the final analyses. The median age was 59.8 years (range, 30.4-86.7 years); 70% were male, 89% were white, and 7% were Asian. There were 2 deaths possibly related to the study drug (cardiac arrest and respiratory failure). Grade 4 adverse events included hyperglycemia, anemia, and lung infection (1 each). Grade 3 adverse events occurred in < 5% of patients except for fatigue (6%). Other adverse events (all grades) included anemia (17%), anorexia (30%), diarrhea (26%), fatigue (50%), hyperglycemia (30%), nausea (40%), vomiting (22%), dry skin (19%), maculopapular rash (30%), and acneiform rash (13%). The response rate was 1%, the median progression-free survival was 1.8 months (95% confidence interval, 1.7-1.8 months), and the median overall survival was 5.1 months (95% confidence interval, 3.7-9.4 months) CONCLUSIONS: MK-2206 as second-line therapy was well tolerated by an unselected group of patients with gastric/gastroesophageal junction cancers, but it did not have sufficient activity (response rate, 1%; overall survival, 5.1 months) to warrant further testing in this population.

SWOG0919: a Phase 2 study of idarubicin and cytarabine in combination with pravastatin for relapsed acute myeloid leukaemia.

Inhibition of cholesterol synthesis and uptake sensitizes acute myeloid leukaemia (AML) blasts to chemotherapy. A Phase 1 study demonstrated the safety of high dose pravastatin given with idarubicin and cytarabine in patients with AML and also demonstrated an encouraging response rate. The Southwestern Oncology Group (SWOG) trial, SWOG S0919, was a Phase 2 trial evaluating the complete remission (CR) rate in a larger number of patients with relapsed AML treated with idarubicin, cytarabine and pravastatin. This study closed to accrual after meeting the defined criterion for a positive study. Thirty-six patients with a median age of 59 years (range 23-78) were enrolled. The median time from diagnosis to registration was 18 months. Relapse status was first relapse, 17 patients (47%); second relapse, 15 patients (42%); third relapse, two patients (5·5%) and fourth relapse, two patients (5·5%). The response rate was 75% [95% confidence interval: 58-88%; 20 CRs, 7 CR with incomplete count recovery (CRi)], and the median overall survival was 12 months. The P-value comparing 75-30% (the null response rate based on prior SWOG experience) was 3·356 × 10(-4) . Given the encouraging CR/CRi rate, this regimen should be considered for testing in a prospective randomized trial against best conventional therapy.

SWOG S0910: a phase 2 trial of clofarabine/cytarabine/epratuzumab for relapsed/refractory acute lymphocytic leukaemia.

Precursor B-acute lymphoblastic leukaemias (pre-B ALLs) comprise the majority of ALLs and virtually all blasts express CD22 in the cytoplasm and on the cell surface. In the present study (Southwestern Oncology Group S0910), we evaluated the addition of epratuzumab, a humanized monoclonal antibody against CD22, to the combination of clofarabine and cytarabine in adults with relapsed/refractory pre-B ALL. The response rate [complete remission and complete remission with incomplete count recovery] was 52%, significantly higher than our previous trial with clofarabine/cytarabine alone, where the response rate was 17%. This result is encouraging and suggests a potential benefit to adding epratuzumab to chemotherapy for ALL; however, a randomized trial will be needed to answer this question.