Health-related quality of life (HRQoL) associated with fruquintinib in the global phase 3, placebo-controlled, double-blind FRESCO-2 study

67

Background: The global phase 3 FRESCO-2 study, (NCT04322539) demonstrated that fruquintinib (F) vs placebo (P) significantly improved OS (HR=0.66 [95% CI: 0.55-0.80]; p<0.001) and PFS (HR=0.32 [95% CI: 0.27-0.39]; p<0.001) in heavily pre-treated patients (pts) with refractory metastatic colorectal cancer (mCRC). F safety profile was consistent with the established monotherapy profile. Here we report the HRQoL and tolerability results. Methods: Pts were randomized 2:1 to F + BSC or P + BSC. EORTC QLQ-C30 and EQ-5D-5L were assessed at baseline and on Day (D) 1 of each Cycle (C) until treatment discontinuation, and ECOG PS was assessed at baseline, D1 of each C, and D21 of C1 to C3. Least-squares mean (LSM) change from baseline to post-baseline visits and the difference between F and P in QLQ-C30 scale scores (e.g. global health status [GHS]/QoL) and EQ-5D-5L scale scores (e.g. visual analog scale [VAS]) were calculated using mixed model repeated measures approach. For each scale, the appropriate minimally important difference (MID) thresholds were determined to evaluate the improvement or deterioration. Time to deterioration (TTD), defined as worsening from baseline in scale-specific MID or death, was analyzed using Kaplan-Meier method, adjusted log-rank test, and stratified Cox PH model. QLQ-C30 and EQ-5D-5L analyses were conducted on the ITT population, and ECOG PS was on the safety population. Results: 691 pts were randomized (F: 461 vs P: 230) and 686 pts received study drug (F: 456 vs P: 230). Median treatment Cycles received (range) were 3 (1, 20) for F vs 2 (1, 13) for P. More than 79% of pts on both arms had a baseline and ≥1 post-baseline assessment for QLQ-C30, EQ-5D-5L, and ECOG PS. GHS/QoL was similar between F and P at baseline; the LSM differences between F and P were 1.7 (95% CI: -1.7, 5.0) for C2 and 1.6 (95% CI: -3.2, 6.4) for C3. At C4, <30 P patients were available. The % of patients who remained stable (MID -6.38 to <8.43) or improved (≥8.43) was numerically higher for F vs P (C2: 61.5% vs 57.1%; C3: 56.4% vs 50.9%). Median TTD was 2.1 months in F and 1.8 months in P (HR=0.9; 95% CI: 0.7-1.0; P=0.098). EQ-5D VAS was similar between F and P at baseline; the LSM differences between F and P were 0.6 (95% CI: -2.3, 3.5) for C2 and 1.4 (95% CI: -2.8, 5.6) for C3. The % of patients who remained stable (MID -7 to <7) or improved (≥7) was similar for F and P (C2: 64.6% vs 58.3%; C3: 64.2% vs 64.8%). Median TTD was 2.6 months in F and 1.9 months in P (HR=0.8; 95% CI: 0.6-0.9; P=0.001). The % of patients with ≥1-point increase from baseline in ECOG PS was 52.1% in F vs 54.0% in P. Conclusions: HRQoL is not negatively impacted by treatment with F. TTD in health utility instrument EQ-5D is improved for patients receiving F. These results, along with improved OS and PFS and favorable toxicity profile, further support F as a potential new treatment option for patients with refractory mCRC. Clinical trial information: NCT04322539 .

Prognostic Impact of Early Treatment and Oxaliplatin Discontinuation in Patients With Stage III Colon Cancer: An ACCENT/IDEA Pooled Analysis of 11 Adjuvant Trials

PURPOSE

Oxaliplatin-based adjuvant chemotherapy in patients with stage III colon cancer (CC) for 6 months remains a standard in high-risk stage III patients. Data are lacking as to whether early discontinuation of all treatment (ETD) or early discontinuation of oxaliplatin (EOD) could worsen the prognosis.

MATERIALS AND METHODS

We studied the prognostic impact of ETD and EOD in patients with stage III CC from the ACCENT/IDEA databases, where patients were planned to receive 6 months of infusional fluorouracil, leucovorin, and oxaliplatin or capecitabine plus oxaliplatin. ETD was defined as discontinuation of treatment and EOD as discontinuation of oxaliplatin only before patients had received a maximum of 75% of planned cycles. Association between ETD/EOD and overall survival and disease-free survival (DFS) were assessed by Cox models adjusted for established prognostic factors.

RESULTS

Analysis of ETD and EOD included 10,447 (20.9% with ETD) and 7,243 (18.8% with EOD) patients, respectively. Compared with patients without ETD or EOD, patients with ETD or EOD were statistically more likely to be women, with Eastern Cooperative Oncology Group performance status ≥ 1, and for ETD, older with a lower body mass index. In multivariable analyses, ETD was associated with a decrease in disease-free survival and overall survival (hazard ratio [HR], 1.61, P < .001 and HR, 1.73, P < .001), which was not the case for EOD (HR, 1.07, P = .3 and HR, 1.13, P = .1). However, patients who received < 50% of the planned cycles of oxaliplatin had poorer outcomes.

CONCLUSION

In patients treated with 6 months of oxaliplatin-based chemotherapy for stage III CC, ETD was associated with poorer oncologic outcomes. However, this was not the case for EOD. These data favor discontinuing oxaliplatin while continuing fluoropyrimidine in individuals with significant neurotoxicity having received > 50% of the planned 6-month chemotherapy.

Prognostic and predictive molecular biomarkers in advanced colorectal cancer

The revolution of precision medicine has produced unprecedented seismic shifts in the treatment paradigm of advanced cancers. Among the major killers, colorectal cancer (CRC) is far behind the others. In fact, the great successes obtained in breast, NSCLC, melanoma, and genitourinary tract tumors have been observed only in fewer than 5 % metastatic colorectal cancer (mCRC): those with the mismatch repair deficiency (dMMR), a well-known predictive factor for to the outstanding efficacy of checkpoint inhibitors (CPI). The treatment of the remaining vast majority mCRC patients is still based upon only two molecular determinants: the RAS and BRAF mutational status. New promising biomarkers include HER2, tumor mutational burden (TMB) for its possible implications on CPI efficacy, and the extremely rare NTRK fusions. The Consensus Molecular Subtypes classification (CMS) is a good example of the efforts to combine different molecular features of this disease, although its relevance in clinical practice is still under investigation. In this Review, we focus on all these prognostic and predictive biomarkers, analyzing data from the most important clinical trials of the last years. We also try to rank them according to their prognostic and predictive power.

Clinical Trial Endpoints in Metastatic Cancer: Using Individual Participant Data to Inform Future Trials Methodology

Meta-analysis based on individual participant data (IPD) is a powerful methodology for synthesizing evidence by combining information drawn from multiple trials. Hitherto, its principal application has been in questions of clinical management, but an increasingly important use is in clarifying trials methodology, for instance in the selection of endpoints, as discussed in this review. In oncology, the Aide et Recherche en Cancérologie Digestive (ARCAD) Metastatic Colorectal Cancer Database is a leader in the use of IPD-based meta-analysis in methodological research. The ARCAD database contains IPD from more than 38 000 patients enrolled in 46 studies and continues to collect phase III trial data. Here, we review the principal findings of the ARCAD project in respect of endpoint selection and examine their implications for cancer trials. Analysis of the database has confirmed that progression-free survival (PFS) is no longer a valid surrogate endpoint predictive of overall survival in the first-line treatment of colorectal cancer. Nonetheless, PFS remains an endpoint of choice for most first-line trials in metastatic colorectal cancer and other solid tumors. Only substantial PFS effects are likely to translate into clinically meaningful benefits, and accordingly, we advocate an oncology research model designed to identify highly effective treatments in carefully defined patient groups. We also review the use of the ARCAD database in assessing clinical response including novel response metrics and prognostic markers. These studies demonstrate the value of IPD as a tool for methodological studies and provide a reference point for the expansion of this approach within clinical cancer research.

Randomized intermittent or continuous panitumumab plus FOLFIRI (FOLFIRI/PANI) for first-line treatment of patients (pts) with RAS/BRAF wild-type (wt) metastatic colorectal cancer (mCRC): The IMPROVE study

3503

Background: Continuous anti-EGFR-based FOLFIRI is a first-line standard of care in pts with RAS/BRAF wt mCRC. The emergence of resistance and treatment-related toxicity limit the efficacy of continuous treatment. Thus, an intermittent strategy could reduce both toxicity and resistance. Methods: This is a prospective, randomized, non-comparative, open-label, multicenter phase II study. Unresectable, previously untreated RAS/BRAF wt mCRC pts, were randomized to a control arm (A) receiving FOLFIRI/PANI continuously until progression or to the experimental arm (B), receiving 8 cycles of the same regimen followed by a treatment free interval. This lasted untill progressive disease, when another treatment period of up to 8 cycles was restarted. This intermittent strategy was continued until progression occurred on treatment. Tumor assessment was always done every 8 weeks in both arms. Pts were stratified for center, ECOG PS (0-1 vs 2), previous adjuvant therapy (yes or no), sidedness (right vs left) and metastatic sites (1 vs ≥ 2). The primary endpoint was the progression-free survival on treatment (PFSOT) at 1 year. Assuming p1=43% PFSOT at 1 year, corresponding to an expected median PFSOT time ≥ 10 months in the experimental arm, and a 5% drop-out rate, a sample size of 68 pts in each arm granted the study a power of 80%, with a type I error of 10% (binomial test) for rejecting the null hypothesis, p0=30%, corresponding to a median PFSOT time of ≤ 7 months. Secondary endpoints were safety, quality of life, OS and response rate (ORR); ctDNA samples were also collected. No formal comparison between the two arms was planned. Results: From May 2018 to June 2021, 137 pts were randomized (69 arm A/68 arm B). Main pts’ characteristics were (arm A/B): males 59/61%; median age 62/66yrs; PS 0 84/72%; right colon 17/15%; previous adjuvant therapy 22/29%; single metastatic site 33/26%. At a median follow-up of 18 months (IQR: 10-26), median PFS OT was 12.6 months (95% CI: 9.0-16.1) in arm A and 17.6 months (95% CI: 7.5-27.8) in arm B with a 1 year PFSOT rate of 51.7% and 61.3%, respectively. ORR (arm A/B) was 64/56%. Median number of FOLFIRI/PANI cycles administered per patient were (arm A/B) 13/12. Main grade 3-4 toxicities were (arm A/B): skin 27/13%, neutropenia 23/22%; diarrhea 13/15%. Conclusions: The primary endpoint of the study was met with the intermittent FOLFIRI-PANI strategy producing a long PFS with a reduced skin toxicity. These data deserve further investigations in a phase III trial. Clinical trial information: NCT04425239.

Metastatic Colorectal Cancer Outcomes by Age Among ARCAD First- and Second-Line Clinical Trials

BACKGROUND

We evaluated the time to progression (TTP) and survival outcomes of second-line therapy for metastatic colorectal cancer among adults aged 70 years and older compared with younger adults following progression on first-line clinical trials.

METHODS

Associations between clinical and disease characteristics, time to initial progression, and rate of receipt of second-line therapy were evaluated. TTP and overall survival (OS) were compared between older and younger adults in first- and second-line trials by Cox regression, adjusting for age, sex, Eastern Cooperative Oncology Group Performance Status, number of metastatic sites and presence of metastasis in the lung, liver, or peritoneum. All statistical tests were 2-sided.

RESULTS

Older adults comprised 16.4% of patients on first-line trials (870 total older adults aged >70 years; 4419 total younger adults aged ≤70 years, on first-line trials). Older adults and those with Eastern Cooperative Oncology Group Performance Status >0 were less likely to receive second-line therapy than younger adults. Odds of receiving second-line therapy decreased by 11% for each additional decade of life in multivariable analysis (odds ratio = 1.11, 95% confidence interval = 1.02 to 1.21, P = .01). Older and younger adults enrolled in second-line trials experienced similar median TTP and median OS (median TTP = 5.1 vs 5.2 months, respectively; median OS = 11.6 vs 12.4 months, respectively).

CONCLUSIONS

Older adults were less likely to receive second-line therapy for metastatic colorectal cancer, though we did not observe a statistical difference in survival outcomes vs younger adults following second-line therapy. Further study should examine factors affecting decisions to treat older adults with second-line therapy. Inclusion of geriatric assessment may provide better criteria regarding the risks and benefits of second-line therapy.

Prognostic impact of early treatment discontinuation and early oxaliplatin discontinuation in patients treated with 6 months of oxaliplatin-based adjuvant chemotherapy for stage III colon cancer: an ACCENT/IDEA pooled analysis of 11 trials

11

Background: Six months of oxaliplatin-based adjuvant chemotherapy in patients with stage III colon cancer (CC) remains a standard in high-risk stage III patients. Early treatment discontinuation (ETD) could worsen the prognosis. In addition, there is current lack of data on the prognostic impact of early oxaliplatin only discontinuation (EOD). Methods: We studied the prognostic impact of ETD and EOD in patients with stage III CC who participated in 11 relevant clinical trials of the ACCENT and IDEA databases, where patients were planned to receive 6 months of adjuvant fluoropyrimidine plus oxaliplatin (FOLFOX or CAPOX). ETD was defined as discontinuation of treatment before 75% of cycles of chemotherapy. EOD was defined as discontinuation of oxaliplatin only, while continuing the fluoropyrimidine, before 75% of cycles of oxaliplatin. Association between ETD/EOD and overall survival (OS) and disease-free survival (DFS) was assessed by Cox model adjusted for prognostic factors. Results: ETD analysis included 10,444 patients (FOLFOX n = 7,033; CAPOX n = 3,411), with 20.9% of patients with ETD (17.8% with FOLFOX and 27.2% with CAPOX, p < 0.001). Out of 7,243 patients, 18.8% experienced EOD (17.4% FOLFOX versus 21.4% with CAPOX, p < 0.001). Compared to patients without ETD or EOD, patients with ETD or EOD were statistically more likely to be women, older, with higher ECOG-PS ≥ 1, and in addition for ETD, a Body Mass Index (BMI) < 18.5 kg/m2. In multivariate analyses, ETD was associated with a decrease in DFS and OS in the overall population (HR: 1.40 95%CI 1.23-1.58, p < 0.001 and HR: 1.51 95%CI 1.31-1.74, p < 0.001, respectively). The same pattern was present with FOLFOX and CAPOX regimen, and also in low-risk and high-risk groups for each regimen with the exception of the CAPOX regimen in the low-risk group for DFS and OS. By contrast, EOD was not associated with reduced DFS or OS in the overall population (HR: 1.10 95%CI 0.77-1.58, p = 0.6 and HR: 0.97 95%CI 0.62-1.52, p = 0.9, respectively), in the low-risk group (HR: 0.97 95%CI 0.56-1.66, p = 0.9 and HR: 0.97 95%CI 0.51-1.82, p = 0.9, respectively) and high-risk group (HR: 1.22 95%CI 0.74-2.02, p = 0.4 and HR: 1.05 95%CI 0.53-2.08, p = 0.9, respectively) and for all subgroups of regimen. Conclusions: In patients treated with 6 months of oxaliplatin-based adjuvant chemotherapy for stage III CC, ETD was associated with a decrease in DFS and OS. By contrast, EOD was not significantly associated with poorer outcomes. In case of relevant neurotoxicity during a 6 months schedule, these data are not in favor of continuing oxaliplatin beyond 75% of planned cycles of adjuvant chemotherapy, and demonstrate that fluoropyrimidines remain the cornerstone of adjuvant chemotherapy in localized CC.

Effect of trifluridine/tipiracil in patients treated in RECOURSE by prognostic factors at baseline: an exploratory analysis

Background

The choice of treatment in patients with metastatic colorectal cancer (mCRC) is generally influenced by tumour and patient characteristics, treatment efficacy and tolerability, and quality of life. Better patient selection might lead to improved outcomes.

Methods

This post hoc exploratory analysis examined the effect of prognostic factors on outcomes in the Randomized, Double-blind, Phase 3 Study of trifluridine tipiracil (FTD/TPI) plus Best Supportive Care (BSC) versus Placebo plus BSC in Patients with mCRC Refractory to Standard Chemotherapies (RECOURSE) trial. Patients were redivided by prognosis into two subgroups: those with <3 metastatic sites at randomisation (low tumour burden) and ≥18 months from diagnosis of metastatic disease to randomisation (indolent disease) were included in the good prognostic characteristics (GPC) subgroup; the remaining patients were considered to have poor prognostic characteristics (PPC).

Results

GPC patients (n=386) had improved outcome versus PPC patients (n=414) in both the trifluridine/tipiracil and placebo arms. GPC patients receiving trifluridine/tipiracil (n=261) had an improved median overall survival (9.3 vs 5.3 months; HR (95% CI) 0.46 (0.37 to 0.57), p<0.0001) and progression-free survival (3.3 vs 1.9 months; HR (95% CI) 0.56 (0.46 to 0.67), p<0.0001) than PPC patients receiving trifluridine/tipiracil (n=273). Improvements in survival were irrespective of age, Eastern Cooperative Oncology Group Performance Status (ECOG PS), KRAS mutational status, and site of metastases at randomisation. In the trifluridine/tipiracil arm, time to deterioration of ECOG PS to ≥2 and proportion of patients with PS=0–1 discontinuing treatment were longer for GPC than for PPC patients (7.8 vs 4.2 months and 89.1% vs 78.4%, respectively).

Conclusion

Low tumour burden and indolent disease were factors of good prognosis in late-line mCRC, with patients experiencing longer progression-free survival and greater overall survival.

Early-onset stage II/III colorectal adenocarcinoma in the IDEA database: Treatment adherence, toxicities, and outcomes from adjuvant fluoropyrimidine and oxaliplatin

3517

Background: Incidence of early-onset colorectal cancer (eoCRC, age < 50) is steadily increasing. Decisions on adjuvant treatment (adjTx) regimen and duration should consider tx adherence, toxicity (tox) and expected outcomes in a population with life-expectancy longer than late onset CRC (loCRC, age ≥ 50). Methods: Individual patient data from stage II/III patients (pts) from 6 randomised trials in the IDEA database were used to compare characteristics, tx adherence, and adverse events of eoCRC to loCRC. To reduce the confounder of non-cancer-related deaths due to age/co-morbidities, time-to-recurrence (TTR) and cancer-specific survival (CSS) were compared by stratified Gay k-sample test. 5-year cancer-specific mortality (CSM) rate were estimated by adjusted cumulative incidence function. 3-year relapse-free survival (RFS) rate were compared by stratified and adjusted COX models. Results: Out of 16,349 pts included, 1564 (9.6%) were eoCRC. Compared to loCRC, eoCRC had lower percent of male pts (51% vs 57%, p < 0.01) better performance status (PS0 86% vs 80%, p < 0.01), similar T stage distribution (% T1-3/T4: 76/24 vs 77/23, p = 0.97), higher rate of N2 disease (24% vs 22%, p < 0.01), more likely to complete pre-planned duration of adjTx (83.2% vs 78.2%, p < 0.01) and received a higher tx intensity especially with 6 month tx (mean oxaliplatin dose intensity 75% vs 72%, p < 0.01; capecitabine 85% vs 78%, p < 0.01; 5FU 85% vs 82% p < 0.01). Gastrointestinal tox was more common in eoCRC (any grade nausea 58% vs 45%, p < 0.01; any grade vomiting 22% vs 16%, p < 0.01); haematological tox was more frequent in loCRC (62% vs, 69%, p = < 0.01); any grade neuropathy rate was similar (75%). Significant interaction was found between age and T stage for TTR (p = 0.04). Clinical outcome estimates and comparisons are shown in Table. Notably, high risk stage III (T4/N2) eoCRC had significantly lower 3-y RFS rate (54% vs 64%, HRadj 0.74, p < 0.01). Conclusions: eoCRC have better tx adherence than loCRC, as expected. While in high risk stage II and low risk stage III, cancer-specific outcomes are not different, in high risk stage III young age is negatively prognostic and associated with significantly higher relapse rate and risk of CRC death; this is despite a higher administered adjTx-intensity, suggesting a more aggressive disease biology. Clinical trial information: NCT00749450 (SCOT); NCT00646607 (TOSCA); NCT01150045 (CALGB/SWOG 80702); NCT00958737 (IDEA France) [Table: see text]

Characteristics of patients (pts) and prognostic factors across treatment lines (TL) in metastatic colorectal cancer (mCRC): An analysis from the Analysis and Research in Cancers of the Digestive System (ARCAD) database

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Background: Pts with mCRC frequently receive ≥1 sequential treatment TL. Approximately 50%-60% of pts receive second-line (L2) and 20%-30% third-line (L3) regimens in routine practice. We investigated the pts clinical/tumor characteristics and their prognostic impact across TL. Methods: Data from 37,560 pts enrolled in 48 randomized trials (34 in first (L1), 9 in L2, and 5 in L3) were analyzed. Candidate variables (VAR) measured at enrollment were sex, age, body mass index, performance status (PS), bilirubin, hemoglobin (Hb), platelets (Pl), derived white blood cells-to-absolute neutrophil counts ratio (WBC/ANC), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), primary tumor location, and number and location of metastatic sites (MS). Missing data were imputed. VAR with significant value at all TL were selected to construct a prognostic score of overall survival (OS) in training set (TS, n=30,050; 80%). For each TL, the score was calculated as the sum on the estimations of the VAR’ coefficients from the common multivariate model; Cox’s model was used to define risk groups. The discrimination capability was assessed using the Harrell’s C-index. External validation was done in the validation set (VS, n=7,510; 20%). Results: A total of 26,974 pts in L1, 7,693 pts in L2 and 2,893 pts in L3 were analyzed. The following characteristics increased continuously over TL: ≥2 MS (57%, 72%, 82%), lung metastases (50%, 74%, 91%), lymph nodes metastases (51%, 61%, 80%), KRAS mutation (37%, 47%, 51%) and elevated ALP (46%, 52%, 61%). BRAF mutation decreased (9%, 7%, 5%). In L1 vs L3 trials, 70% vs 89% of patients had primary tumor resection, 10% vs 80% had at least one metastasectomy and 31% vs 78% had a late metachronous (>12 months) metastasis. 7 independent VAR were retained in the prognostic score (PS, Hb, Pl, WBC/ANC, LDH, ALP, and the number of MS); four pt groups with significantly different prognoses were defined (table). This score remained valid when excluding pts with PS 2. Third-line oral drugs (vs placebo) and subsequent line (L2/L1 or L3/L2) were effective in all prognostic groups. Conclusions: Clinical/tumor pt characteristics significantly varied over subsequent TL in patients included in randomized trials. The same prognostic model using practical clinical and biological variables can be used in all TL.[Table: see text]

Duration of Adjuvant Doublet Chemotherapy (3 or 6 months) in Patients With High-Risk Stage II Colorectal Cancer

PURPOSE

As oxaliplatin results in cumulative neurotoxicity, reducing treatment duration without loss of efficacy would benefit patients and healthcare providers.

PATIENTS AND METHODS

Four of the six studies in the International Duration of Adjuvant Chemotherapy (IDEA) collaboration included patients with high-risk stage II colon and rectal cancers. Patients were treated (clinician and/or patient choice) with either fluorouracil, leucovorin, and oxaliplatin (FOLFOX) or capecitabine and oxaliplatin (CAPOX) and randomly assigned to receive 3- or 6-month treatment. The primary end point is disease-free survival (DFS), and noninferiority of 3-month treatment was defined as a hazard ratio (HR) of < 1.2- v 6-month arm. To detect this with 80% power at a one-sided type one error rate of 0.10, a total of 542 DFS events were required.

RESULTS

3,273 eligible patients were randomly assigned to either 3- or 6-month treatment with 62% receiving CAPOX and 38% FOLFOX. There were 553 DFS events. Five-year DFS was 80.7% and 83.9% for 3-month and 6-month treatment, respectively (HR, 1.17; 80% CI, 1.05 to 1.31; P [for noninferiority] .39). This crossed the noninferiority limit of 1.2. As in the IDEA stage III analysis, the duration effect appeared dependent on the chemotherapy regimen although a test of interaction was negative. HR for CAPOX was 1.02 (80% CI, 0.88 to 1.17), and HR for FOLFOX was 1.41 (80% CI, 1.18 to 1.68).

CONCLUSION

Although noninferiority has not been demonstrated in the overall population, the convenience, reduced toxicity, and cost of 3-month adjuvant CAPOX suggest it as a potential option for high-risk stage II colon cancer if oxaliplatin-based chemotherapy is suitable. The relative contribution of the factors used to define high-risk stage II disease needs better understanding.

FRESCO-2: A global phase III study of the efficacy and safety of fruquintinib in patients (pts) with metastatic colorectal cancer (mCRC)

TPS154

Background: Pts with mCRC have limited treatment options following progression on standard therapies. Current standard of care (SOC) after pts progress on trifluridine/tipiracil (TAS-102) or regorafenib is re-challenge with previous systemic treatments, enrollment in a clinical trial, or best supportive care (BSC). Fruquintinib (Elunate) is a novel, highly selective, vascular endothelial growth factor (VEGF) receptor (VEGFR)-1, -2, and -3 tyrosine kinase inhibitor (TKI) ( Cancer Biol Ther 2014;15:1635-1645). Fruquintinib is approved in China to treat pts with mCRC who received or are intolerant to fluoropyrimidine-, oxaliplatin-, and irinotecan-based chemotherapy, anti-VEGF therapy, and, if RAS wild type, anti-epidermal growth factor receptor (EGFR) therapy. Approval was based on results of the phase 3 FRESCO study (2013-013-00CH1; NCT02314819; JAMA 2018;319:2486-2496), in which fruquintinib 5 mg daily (QD), 3 weeks on, 1 week off (3 on/1 off), significantly improved overall survival (OS) in pts with mCRC in the 3rd-line+ setting when compared to placebo (median OS 9.3 months [mo] versus 6.6 mo; hazard ratio [HR] 0.65; p < .001). Progression-free survival (PFS) was also superior (median PFS 3.7 mo versus 1.8 mo; HR 0.26; p < .001). The toxicities of fruquintinib were consistent with those of other VEGF TKIs and were manageable. At the time FRESCO was conducted in China, SOC for pts with mCRC differed from that in the US, EU, and Japan. We describe here a global phase 3 study (FRESCO-2; 2019-013-GLOB1; NCT04322539) being conducted to investigate fruquintinib’s efficacy and safety in pts with refractory mCRC and a treatment profile representative of the global SOC. Methods: FRESCO-2 is a randomized, double-blind, placebo-controlled study to compare fruquintinib + BSC to placebo + BSC. Key inclusion criteria are progression on or intolerance to treatment with TAS-102 and/or regorafenib; previous treatment with standard approved therapies including chemotherapy, anti-VEGF therapy, and, if RAS wild type, anti-EGFR therapy. Prior therapy with immune checkpoint or BRAF inhibitors is required for pts with corresponding tumor alterations. Pts (~522) will be randomized 2:1 to receive either fruquintinib 5 mg orally (PO) QD + BSC or placebo 5 mg PO QD + BSC, with a 3 on/1 off schedule. Randomization will be stratified by prior therapy, RAS status, and duration of metastatic disease. The primary endpoint is OS; secondary endpoints include PFS, disease control rate, objective response rate, duration of response, and safety. Final OS analyses will be performed when 364 OS events are observed; futility analysis will be conducted with 1/3 (121) OS events. If enrichment of post-regorafenib pts occurs, enrollment to that strata will be capped at approximately 262. FRESCO-2 will be activated in the US, EU, and Japan; global enrollment is anticipated over 13 mo. Clinical trial information: NCT04322539.

A new prognostic and predictive tool for shared decision making in stage III colon cancer

BACKGROUND

Survival of patients with stage III colon cancer varies widely according to T-N sub-stages. Estimating the benefit of each therapeutic option in each T-N subgroup may provide more accurate information helping doctors and patients in the complex shared decision-making process surrounding adjuvant therapy.

METHODS

The outcomes data of 12,834 patients with stage III colon cancer enrolled in the IDEA trial served as our database. Patients were categorised in 16 sub-stages, based on T-N categories. We created a meta-regression model to predict the expected 5-year DFS within each T-N sub-stage. We then evaluated the efficacy of each therapeutic option in every sub-stage, working backward by subtraction, using an average of the HRs reported in pertinent trial publications as a conversion factor.

RESULTS

Large differences in 5-year DFS rate were observed among the subgroups, ranging from 89% (T1N1a) to 31% (T4N2b) in the overall population. The contribution to the outcome of each therapeutic option in this setting varied widely across sub-stages. According to our model, patients with T1N1a cancers have a projected 5-year DFS of 79.6% with surgery alone. Adjuvant fluoropyrimidine alone results in 5.6% absolute DFS gain; an additional 2.3% and 0.8% gain is seen with oxaliplatin for 3 and 6 months, respectively. Patients with T4N2b cancers show a 13.9% 5-year DFS with surgery alone, and an 11.2%, 6.4%, 2.5% increase with the aforementioned adjuvant options, respectively.

CONCLUSION

The resulting overlay bar graph gives patients and doctors the projected relative benefit of each treatment option and may substantially help the shared decision-making process, although caution must be exercised in using this model due to the significant variance of the estimates.

A new prognostic and predictive tool to enhance shared decision making in stage III colon cancer

4010

Background: Survival outcomes in patients with stage III colon cancer varies widely according to T-N sub-stages. The ability to estimate the benefit of each therapeutic option (surgery alone, fluoropyrimidines alone, oxaliplatin-based doublet for either 3 or 6 months) in each T-N subgroup within stage III, may provide more accurate information helping doctors and patients in the complex shared decision-making process surrounding adjuvant therapy. Methods: Theoutcomedata of 12,834 patients with stage III colon cancer enrolled in the IDEA trial served as our database. Patients were categorized in 16 sub-stages, based on the T-N categories. We created a meta-regression model to predict the expected 3-year DFS within each T-N sub-stage and hence the 5-year DFS rates were projected. We then evaluated the efficacy of each therapeutic option in every sub-stage, working backward by subtraction, using an average of the HRs reported in the pertinent trials publication as conversion factor. Results: Large differences in 3-year DFS rate were observed among the subgroups, ranging from 95% (T1N1a) to 29% (T4N2b) in the overall population. The contribution to outcome of each therapeutic option in this setting varied widely across sub-stages. According to our model, patients with T1N1a cancers have a projected 5-year DFS of 85% with surgery alone. Adjuvant fluoropyrimidine alone results in 4.2% absolute DFS gain; an additional 1.7% and 0.6% gain is seen with oxaliplatin for 3 and 6 months, respectively. Patients with T4N2b cancers show a 4.7% 5-year DFS with surgery alone, and a 7.1%, 5.0%, 2.1% increase with the aforementioned adjuvant options, respectively. Conclusions: The resulting overlay bar graph gives patients and doctors the projected relative benefit of each treatment option and may substantially help the shared decision-making process.

Survival outcomes among older adults (OA) receiving second-line therapy for metastatic CRC (mCRC): 5,289 patients (pts) from the ARCAD Clinical Trials Program

7009

Background: Survival outcomes of 2nd line mCRC therapy for OA are poorly understood. We evaluated the rates and survival outcomes of 2nd line therapy among OA age 70+ compared to younger adults (YA) age < 70 following progression on 1st line clinical trials. Methods: Associations between clinical characteristics of pts with available treatment data after progression on 10 of 23 1st line ARCAD trials, time to initial progression (TTiP) and 2nd line therapy were evaluated. Time to progression (TTP) and overall survival (OS) were compared between OA and YA enrolled on 2nd line trials by Cox regression, adjusting for age, sex, ECOG PS, number of metastatic sites, presence of metastasis in lung/liver/peritoneum. Results: Sixteen percent of 1st line ARCAD trial participants were age 70+ (n = 870). Data for 2nd line therapy was available for 60.6% pts (3206/5289). Each additional decade of life was associated with 11% lower odds of receiving 2nd line therapy in multivariate analysis (p = 0.0117). OA participating in 2nd line trials (7.9% age 75+ of 7921) experience similar TTP and OS to YA (mTTP: 5.1 vs. 5.2mos; mOS 11.6 vs 12.4mos, respectively). Conclusions: We did not observe a statistical difference in survival outcomes by age following 2nd line mCRC therapy. Further study is needed to examine unmeasured comorbidity and use of geriatric assessment to select OA likely to benefit from 2nd line therapy. [Table: see text]

Overall survival (OS) and long-term disease-free survival (DFS) of three versus six months of adjuvant (adj) oxaliplatin and fluoropyrimidine-based therapy for patients (pts) with stage III colon cancer (CC): Final results from the IDEA (International Duration Evaluation of Adj chemotherapy) collaboration

4004

Background: In overall population, IDEA pooled analysis did not demonstrate non-inferiority (NI) regarding 3y DFS in pts with stage III CC receiving 3m vs. 6m of adj FOLFOX/CAPOX. However, in pts treated with CAPOX (especially in low-risk pts), 3m of therapy was as effective as 6m. Results of OS and 5y DFS are reported. Methods: OS was defined as time from enrollment to death due to all causes. OS NI margin was conservatively set to be Hazard Ratio (HR) = 1.11, which is equivalent to: the maximum acceptable loss of OS efficacy, by shortening treatment to 3m, was half of the OS efficacy gained in MOSAIC trial (i.e., 2.26% absolute reduction in 5y OS rate). Pre-planned sub-group analyses included by regimen and risk group for both OS and 5y DFS. NI was to be declared if the one-sided false discovery rate adjusted (FDRa) NI p-value < 0.025. Results: With an overall median survival follow-up of 72 m (range per study, 62 to 84 m), 2584 deaths and 3777 DFS events among 12,835 pts from six trials were observed. Across 6 studies, 39.5% of pts received CAPOX (rate by study, 0% to 75.1%). Overall, the 5y OS rate was 82.4% (3m) and 82.8% (6m), with estimated OS HR of 1.02 (95% confidence interval [CI], 0.95-1.11; FDRa NI p, 0.058) and absolute 5-y OS rate difference of -0.4% (95% CI, -2.1 to 1.3%). Overall, the 5y DFS rate was 69.1% (3m) and 70.8% (6m), with estimated DFS HR of 1.08 (95%CI, 1.01-1.15, FDRa NI p, 0.22). HRs (95% CI) within subgroups see table. Conclusions: 5y OS rate reported in IDEA trials was higher than historical rates, regardless of duration of therapy. While overall survival in IDEA did not meet prior statistical assumptions for NI in overall population, the 0.4% difference in 5y OS should be placed in clinical context. OS and 5y DFS results continue to support the use of 3m adjuvant CAPOX for the vast majority of stage III colon cancer pts. This conclusion is strengthened by the substantial reduction of toxicities, inconveniencies and cost associated with shorter treatment duration. Clinical trial information: NCT01150045; 2009-010384-16; NCT00749450; ISRCTN59757862; 2007-003957-10; UMIN000008543; 2007-000354 . [Table: see text]

The PEGASUS trial: Post-surgical liquid biopsy-guided treatment of stage III and high-risk stage II colon cancer patients

TPS4124

Background: Moving stage III Colon Cancer (CC) into the precision medicine space is a priority in view of the lack of molecular markers driving adjuvant treatment. Retrospective studies have demonstrated the tremendous prognostic impact of circulating tumor DNA (ctDNA) analysis after curative intent surgery, and suggested that lack of conversion of ctDNA from detectable to undetectable after adjuvant chemotherapy reflects treatment failure. With these premises, we have designed the PEGASUS trial (NCT04259944). Methods: PEGASUS is a prospective multicentric study designed to prove the feasibility of using liquid biopsy (LB) to guide the post-surgical and post-adjuvant clinical management in 140 microsatellite stable Stage-III and T4N0 Stage-II CC patients. The LUNAR1 test (Guardant Health, Redwood City, CA, USA) will be used for ctDNA determination. For the efficacy analysis, the PEGASUS cohort will be compared with a 3:1 matched cohort of 420 patients from the TOSCA trial (NCT00646607). A LB executed 2-4 weeks post-surgery will guide a “Molecular Adjuvant” treatment: i) ctDNA+ patients will receive CAPOX for 3 months and ii) ctDNA- patients will receive capecitabine (CAPE) for 6 months but will be retested after 1 cycle, and if found ctDNA+ will be switched to CAPOX treatment. At the end of the “Molecular Adjuvant” treatment a further LB will be performed and instruct subsequent treatment. Positive patients (ctDNA+/+ and ctDNA-/+) will receive an up-scaled “Molecular Metastatic” systemic treatment for 6 months or until radiological progression or toxicity: i) ctDNA+/+ patients will be treated with FOLFIRI; ii) ctDNA-/+ patients with CAPOX. These patients will be subjected to a LB after 3 months and at the end of treatment: in case of positivity will be switched to FOLFIRI. ctDNA+/- patientswill receive a de-escalated treatment with CAPE for 3 months. 3 LB will be performed within 3 months and in case of positivity the patient will be switched to FOLFIRI. Patients with ctDNA-/- will be subjected to an interventional follow-up comprising 2 further LB and in case of positivity they will be switched to CAPOX treatment. PEGASUS is piggybacked to AlfaOmega (NCT04120935), a Master Observational Protocol that will follow patients from diagnosis to 5 years or recurrence/death (whichever comes first), collecting clinical data, radio-images and biological samples. AlfaOmega provides a clinical and logistic ecosystem for the seamless integration of PEGASUS clinical results with the biological underpinning of colon cancer. Clinical trial information: NCT04259944 .

Treatment effects (TEs) of EGFR monoclonal antibodies (mAbs) in metastatic colorectal cancer (mCRC) patients (pts) with KRAS, NRAS, and BRAF mutation (MT) status: Individual patient data (IPD) meta-analysis of randomized trials from the ARCAD database

4090

Background: EGFR mAbs have become incorporated into clinical practice for the management of mCRC over the last decade. KRAS and NRAS mutations are used as predictive biomarkers and BRAF V600E mutations are associated with an adverse prognosis. The observed TE within biomarker subpopulations has varied between studies. Methods: IPD from randomized trials with head-to-head comparison between EGFR mAb versus no EGFR mAb (chemotherapy alone or BSC) in mCRC, across all lines of therapy (first, second and later), were pooled. Biomarker subpopulations are defined in the table. Overall survival (OS) and progression-free survival (PFS) were compared between groups by Cox model, stratified by studies and adjusted by age, gender, and performance status. TEs were estimated by adjusted hazard ratio (HRadj) and 95% confidence interval (CI). Within each biomarker subgroup, EGFR mAb efficacy was explored according to multiple exploratory factors, including line of therapy, type of backbone chemo, gender, sidedness and site of metastasis. Interaction tests were performed. P-values < 0.01 were considered statistically significant to account for multiple comparisons. Results: 5729 pts from 8 studies with data available for ≥ 1 biomarker were analysed. PFS benefits (median 9.2 mos in EGFR mAbs, 8.0 mos in no EGFR mAbs) were confirmed in triple-WT pts, but not for OS (refer to table). No OS/PFS benefits were observed for pts with any of the MT tumors. Exploratory analyses showed a potential detrimental TE of EGFR mAbs in KRAS MT mCRC with liver metastasis (OS: HRadj 1.22, p = .003, pinteraction .0056; PFS: HRadj 1.24, p = .0009, pinteraction .0008). These results were confirmed within the subgroup of pts with all 3 biomarkers available. Conclusions: This is the largest IPD analysis to explore the predictive value of RAS/BRAF biomarkers in mCRC. Our findings demonstrate that there is no evidence of efficacy of EGFR mAbs in KRAS, BRAF and/or NRAS MT mCRC. EGFR mAbs might have a detrimental effect in KRAS MT mCRC with liver metastases. [Table: see text]

Receipt and survival outcomes by age following second-line therapy for metastatic CRC (mCRC): Analysis of 5,289 patients from the ARCAD Clinical Trials Program

6

Background: Rates and survival outcomes for second-line therapy for mCRC for OA vs. YA are poorly understood. Methods: Pts with available subsequent treatment data after progression from 10 1st line trials were included. Associations between key clinical/disease characteristics, time to initial progression (TTiP) and rate of receipt of second-line therapy were evaluated. Time to progression (TTP) and overall survival (OS) were compared between OA and YA who were enrolled on second-line trials by Cox regression, adjusting for age, sex, ECOG PS, number of metastatic sites, presence of metastasis in lung/liver/peritoneum. Results: OA comprised 16.4% of first-line trials. OA and ECOG PS >0 were less likely to receive second-line therapy than YA. Odds of receiving second-line therapy decreased by 11% for each additional decade of life in multivariate analysis (p=0.0117). OA enrolled in second-line trials experience similar mTTP and mOS as YA (5.1 vs. 5.2mos; 11.6 vs 12.4mos, respectively). Conclusions: OA are less likely to receive 2nd line therapy for mCRC. We did not observe a statistical difference in survival outcomes for OA vs. YA following second-line therapy. Further study is needed to examine unmeasured factors, including comorbidity and functional status given observed inferior outcomes among adults with ECOG PS >0, and consideration given to inclusion of geriatric assessment to select OA likely to benefit from 2nd line therapy for mCRC.

[Table: see text]

Prospective pooled analysis of four randomized trials investigating duration of adjuvant (adj) oxaliplatin-based therapy (3 vs 6 months {m}) for patients (pts) with high-risk stage II colorectal cancer (CC)

3501

Background: 6m of oxaliplatin-based treatment is an option as adj chemotherapy for patients with high risk stage II CC (T4, inadequate nodal harvest, poorly differentiated, obstruction, perforation or vascular/perineural invasion). The IDEA collaboration showed shorter treatment duration to be appropriate for most pts with stage III colon cancer. The results of the 4 IDEA studies with stage II pts are presented here. Methods: A prospective, pre-planned pooled analysis of high-risk stage II patients from 4 concurrently conducted randomized phase III trials (SCOT, TOSCA, ACHIEVE-2, HORG) was performed to evaluate non-inferiority (NI) of 3m compared with 6m (ref) of adj FOLFOX/CAPOX (regimen preselected, not randomized). The primary endpoint was disease-free survival (DFS), NI was to be declared if the 2-sided 80% confidence interval (CI) for DFS hazard ratio (HR 3m v 6m) estimated by a stratified Cox model was below 1.2. 542 DFS events were required to provide 80% power to declare NI. NI was also examined within regimen, T4 (Yes v No) and inadequate nodal harvest (Yes v No) as pre-planned subgroups. Results: The primary analysis included 3273 randomised pts of which 1254 had FOLFOX and 2019 had CAPOX. There were 552 events and the median follow-up was 60.2 m. There was significantly less grade 3-5 toxicity with 3m treatment (p < .0001). The 5-year DFS rate was 80.7% and 84.0% for 3m and 6m treatment with an estimated DFS HR of 1.18 (80% CI:1.05-1.31, p for NI = 0.404). For CAPOX the estimated HR was 1.02 (80% CI: 0.88-1.17, p for NI = 0.087) and for FOLFOX the estimated HR was 1.42 (80% CI: 1.19-1.70, p for NI = 0.894). The test for interaction between duration and regimen was not statistically significant (p = .174 adjusted for multiple testing) but was stronger than that for the other subgroups examined. Conclusions: In the overall population non-inferiority for 3m adj treatment in pts with high-risk stage II CC was not shown. As with the stage III population the choice of adj regimen appears important (although this did not reach statistical significance) with a small difference in DFS between 3 and 6 m treatment if CAPOX is used. Clinical trial information: ISRCTN59757862.

Retrospective analysis of overall survival (OS) by subsequent therapy in patients (pts) with RAS wild-type (wt) metastatic colorectal cancer (mCRC) receiving irinotecan ± cetuximab in the EPIC study

3580

Background: The multicenter, open-label, randomized, phase 3 EPIC study (EMR 062202-025) investigated cetuximab + irinotecan vs irinotecan as a second-line (2L) therapy in pts with EGFR-detectable mCRC. A retrospective analysis in the EPIC RAS wt population showed improved overall response rate (29.4% vs 5.0%) and progression-free survival (5.4 vs 2.6 mo) upon the addition of cetuximab to irinotecan. Median OS (mOS) was similar in both treatment arms, possibly due to differences in subsequent therapies. We present OS by post-study therapy in the RAS wt population. Methods: 1298 RAS-unselected pts were enrolled from May 2003 to February 2006. The primary endpoint was OS. RAS status was determined retrospectively in 2018 from existing DNA samples using BEAMing technology; wt status was defined as having a sum of mutated RAS allele frequencies of ≤5%, with all relevant alleles being analyzable. Results: Among the 452 pts with RAS wt mCRC, 231 received cetuximab + irinotecan and 221 received irinotecan. Baseline characteristics were similar in both arms. OS data by post-study therapy are summarized in the Table. No new or unexpected safety signals were observed. Conclusions: Post-study cetuximab was associated with improved OS in both treatment arms compared with post-study therapy without cetuximab and no subsequent therapy, suggesting that cetuximab-based therapy may be suitable as a standard treatment for pts with RAS wt mCRC in the rechallenge setting. Study limitations include a potential bias due to the differences in proportion of subsequent therapies with and without cetuximab between arms (almost 50% of pts in the irinotecan arm received post-study cetuximab) as well as the likelihood for pts who live longer to receive cetuximab in any subsequent therapy line. [Table: see text]

Maximising clinical benefit with adequate patient management beyond the second line in mCRC

New therapeutic options for refractory metastatic colorectal cancer (mCRC) include trifluridine/tipiracil (TAS-102) and regorafenib. However, the optimal chemotherapeutic regimen for use of each agent beyond the second line for patients with mCRC remains unclear and various factors may influence treatment decision. Available efficacy data suggest treatment with either trifluridine/tipiracil or regorafenib may be appropriate as both can extend patient survival. Thus, the safety profiles of each agent, along with patient performance status, are likely to determine treatment choice. The safety profiles of trifluridine/tipiracil and regorafenib are markedly different: higher levels of non-haematological adverse events such as fatigue, diarrhoea, hypertension and hand-foot skin reaction are reported with regorafenib, while haematological events such as neutropaenia are more common with trifluridine/tipiracil. In general, neutropaenia is a manageable treatment-related toxicity, while hand-foot skin reaction can be troublesome for patients, affecting their ability to carry out everyday activities and get on with their lives, while also affecting treatment adherence. Thus, the occurrence of any potential adverse effects and patient adherence should be closely monitored at each clinic visit. As quality of life is an important issue for patients with mCRC, it is important to balance extended survival and the likely quality of this extended life. Likewise, discussing possible side effects along with treatment expectations with patients can greatly facilitate adherence to therapy, and ultimately improve patients’ quality of life and eventual clinical outcomes.

Exploratory analysis of the effect of FTD/TPI in patients treated in RECOURSE by prognostic factors

677

Background: The Phase III RECOURSE trial, in patients (pts) with metastatic colorectal cancer (mCRC) refractory to standard therapies, demonstrated that trifluridine/tipiracil (FTD/TPI) significantly extended overall survival (OS) and progression-free survival (PFS) versus placebo in all subgroups, regardless of age, geographical origin, or KRAS status, with acceptable safety. Literature reports have shown optimal benefit for pts with low tumor burden (< 3 metastatic sites), indolent disease (≥ 18 mo since diagnosis of first metastasis), ECOG PS 0-1, and no liver metastasis when treated in late line mCRC. Methods: This exploratory post hoc analysis of RECOURSE (all ECOG 0-1) compared pts on FTD/TPI or placebo with good prognostic characteristics (GPC; low tumor burden and indolent disease) and poor prognostic characteristics (PPC; high tumor burden and/or aggressive disease). These subgroups were then analyzed by liver metastasis at baseline, ECOG PS, KRAS status and age. Results: Baseline characteristics were generally similar between the two groups. GPC placebo pts performed better than the PPC placebo pts, but worse than the GPC pts treated with FTD/TPI. GPC pts treated with FTD/TPI showed median OS of 9.3 mo versus 5.3 mo in PPC pts (HR 0.46; 95% CI: 0.37, 0.57; p < 0.0001); there was a similar effect for PFS. GPC pts had significantly better mOS and mPFS regardless of age (≥ 65 vs. < 65 y), ECOG PS (0–1), KRAS status (mutant vs. wildtype), and liver metastasis (y/n). No liver metastasis was the best prognostic factor: mOS in such pts treated with FTD/TPI was 16.4 mo and 7.6 mo in the GPC (n = 97) and PPC (n = 35) groups, respectively (HR 0.42; 95% CI: 0.24, 0.74; p < 0.0019); there was a similar effect for PFS. Pts with ECOG PS 0 at baseline remained PS 0-1 at discontinuation in 96% of the GPC group. Conclusions: Low tumor burden and indolent disease indicate good prognosis in late line mCRC. Pts with no liver metastasis have the best prognosis and are likely to have longer OS. GPCs might explain the percentage of long-term responders on FTD/TPI in RECOURSE. Maintenance of ECOG PS 0–1 during treatment is crucial in the continuum of care, allowing pts to benefit from further treatment options. Clinical trial information: NCT01607957.

Consensus statement on essential patient characteristics in systemic treatment trials for metastatic colorectal cancer: Supported by the ARCAD Group

BACKGROUND

Patient characteristics and stratification factors are key features influencing trial outcomes. However, there is substantial heterogeneity in reporting of patient characteristics and use of stratification factors in phase 3 trials investigating systemic treatment of metastatic colorectal cancer (mCRC). We aimed to develop a minimum set of essential baseline characteristics and stratification factors to include in such trials.

METHODS

We performed a modified, two-round Delphi survey among international experts with wide experience in the conduct and methodology of phase 3 trials of systemic treatment of mCRC.

RESULTS

Thirty mCRC experts from 15 different countries completed both consensus rounds. A total of 14 patient characteristics were included in the recommended set: age, performance status, primary tumour location, primary tumour resection, prior chemotherapy, number of metastatic sites, liver-only disease, liver involvement, surgical resection of metastases, synchronous versus metachronous metastases, (K)RAS and BRAF mutation status, microsatellite instability/mismatch repair status and number of prior treatment lines. A total of five patient characteristics were considered the most relevant stratification factors: RAS/BRAF mutation status, performance status, primary tumour sidedness and liver-only disease.

CONCLUSIONS

This survey provides a minimum set of essential baseline patient characteristics and stratification factors to include in phase 3 trials of systemic treatment of mCRC. Inclusion of these patient characteristics and strata in study protocols and final study reports will improve interpretation of trial results and facilitate cross-study comparisons.

The Potential Role of Tomudex in the Treatment of Advanced Colorectal Cancer

Aims and Background

The quinazoline folate analog thymidylate synthase inhibitor, Tomudex, is about to enter the Italian pharmaceutical market. Its place among the therapeutic options for advanced colorectal cancer is discussed.

Methods

The pros and cons of currently available chemotherapeutic regimens are briefly described with special attention to patient's and tumor's determinants of treatment outcome. The mechanism of action and the results of phase I, II and III studies of Tomudex are reviewed.

Results

Not all patients need to be treated. Guidelines are given in this respect. Tomudex at the dose of 3 mg/m2 given i.v. every three weeks has antitumor activity similar to that of currently available regimens, with a favorable toxicity profile.

Conclusions

Current research approaches are unlikely to dramatically improve the treatment outcome of this disease in the near future. What can reasonably be expected is less toxicity and more convenient routes and schedules of drug administration that may translate into better quality of life for our patients. Tomudex has been devised along these lines.

Duration of Adjuvant Chemotherapy for Stage III Colon Cancer

BACKGROUND

Since 2004, a regimen of 6 months of treatment with oxaliplatin plus a fluoropyrimidine has been standard adjuvant therapy in patients with stage III colon cancer. However, since oxaliplatin is associated with cumulative neurotoxicity, a shorter duration of therapy could spare toxic effects and health expenditures.

METHODS

We performed a prospective, preplanned, pooled analysis of six randomized, phase 3 trials that were conducted concurrently to evaluate the noninferiority of adjuvant therapy with either FOLFOX (fluorouracil, leucovorin, and oxaliplatin) or CAPOX (capecitabine and oxaliplatin) administered for 3 months, as compared with 6 months. The primary end point was the rate of disease-free survival at 3 years. Noninferiority of 3 months versus 6 months of therapy could be claimed if the upper limit of the two-sided 95% confidence interval of the hazard ratio did not exceed 1.12.

RESULTS

After 3263 events of disease recurrence or death had been reported in 12,834 patients, the noninferiority of 3 months of treatment versus 6 months was not confirmed in the overall study population (hazard ratio, 1.07; 95% confidence interval [CI], 1.00 to 1.15). Noninferiority of the shorter regimen was seen for CAPOX (hazard ratio, 0.95; 95% CI, 0.85 to 1.06) but not for FOLFOX (hazard ratio, 1.16; 95% CI, 1.06 to 1.26). In an exploratory analysis of the combined regimens, among the patients with T1, T2, or T3 and N1 cancers, 3 months of therapy was noninferior to 6 months, with a 3-year rate of disease-free survival of 83.1% and 83.3%, respectively (hazard ratio, 1.01; 95% CI, 0.90 to 1.12). Among patients with cancers that were classified as T4, N2, or both, the disease-free survival rate for a 6-month duration of therapy was superior to that for a 3-month duration (64.4% vs. 62.7%) for the combined treatments (hazard ratio, 1.12; 95% CI, 1.03 to 1.23; P=0.01 for superiority).

CONCLUSIONS

Among patients with stage III colon cancer receiving adjuvant therapy with FOLFOX or CAPOX, noninferiority of 3 months of therapy, as compared with 6 months, was not confirmed in the overall population. However, in patients treated with CAPOX, 3 months of therapy was as effective as 6 months, particularly in the lower-risk subgroup. (Funded by the National Cancer Institute and others.).

Phase II LAPACT trial of nab-paclitaxel (nab-P) plus gemcitabine (G) for patients with locally advanced pancreatic cancer (LAPC)

204

Background: In the phase 3 MPACT study, treatment with nab-P + G resulted in a > 3-fold reduction in primary pancreatic tumor burden vs G in patients with metastatic PC, suggesting the potential for activity against LAPC. This international, multicenter single arm, phase 2 trial (LAPACT) was designed to evaluate the efficacy and safety of an induction phase regimen of nab-P + G in previously untreated patients with LAPC. Methods: Treatment-naive patients with unresectable LAPC and Eastern Cooperative Oncology Group (ECOG) performance status ≤ 1 were enrolled. The induction phase was designed as 6 cycles of nab-P 125 mg/m2 + G 1000 mg/m2 on D 1, 8, and 15 of each 28-day cycle. After induction, patients without progressive disease or unacceptable adverse events were eligible for continued treatment with nab-P + G, chemoradiation, or surgery per investigator’s choice (IC). Surgery could occur prior to completing 6 induction cycles if the investigator deemed there had been a sufficient tumor response. The primary endpoint was time to treatment failure (TTF) in patients treated with nab-P + G as induction therapy followed by IC treatment. Key secondary endpoints included disease control rate (DCR), overall response rate (ORR), progression-free survival (PFS), and overall survival (OS). Results: Of 107 patients enrolled, 106 were evaluable for the safety analysis. No new toxicities were identified. The most common grade ≥ 3 treatment-emergent adverse events during induction were neutropenia (42%), anemia (11%), and fatigue (10%); grade 3 peripheral neuropathy occurred in 4% of patients. The most frequent reasons for discontinuing induction were adverse events (18%) and progressive disease (7%). Forty-six (43%) patients received IC treatment after induction: 13 (12%) continued nab-P + G, 17 (16%) received chemoradiation, and 16 (15%) underwent surgical resection (R0, n = 7; R1, n = 9). DCR and ORR during induction were 78% and 35%, respectively; with a median TTF of 8.6 months and median PFS of 10.2 months. Conclusion: A nab-P + G induction regimen in LAPC appears tolerable and feasible and is associated with encouraging antitumor activity and promising TTF and PFS. NCT02301143. Clinical trial information: NCT02301143.

Prospective pooled analysis of six phase III trials investigating duration of adjuvant (adjuv) oxaliplatin-based therapy (3 vs 6 months) for patients (pts) with stage III colon cancer (CC): The IDEA (International Duration Evaluation of Adjuvant chemotherapy) collaboration

LBA1

Background: Since 2004, 6 months (m) of oxaliplatin (oxali)-based treatment has been the standard of care as adjuvant therapy for stage III CC. Since oxali is associated with cumulative neurotoxicity, shorter duration of adjuv therapy could spare pts toxicity and lead to substantial saving in health expenditures. Methods: A prospective, pre-planned pooled analysis of 6 concurrently conducted randomized phase III trials (SCOT, TOSCA, Alliance/SWOG 80702, IDEA France (GERCOR/PRODIGE), ACHIEVE, HORG) was performed to evaluate the non-inferiority (NI) of 3m compared with 6m (ref) of adjuv FOLFOX/XELOX. The primary endpoint was disease-free survival (DFS), defined as time from enrolment to relapse, 2nd CRC, and death (all causes). NI was to be declared if the 2-sided 95% confidence interval (CI) for DFS hazard ratio (HR 3m v 6m) estimated by a stratified Cox model was below 1.12. NI was examined within regimen and stage subgroups as pre-planned. Results: The analysis included 12,834 pts from 12 countries, accrued from 6/07 to 12/15. Stage distribution: 13% T1-2, 66% T3, 21% T4; 28% N2; 40% received XELOX. G3+ neurotoxicity was higher in the 6m v 3m arm (16 v 3% FOLFOX, 9 v 3% XELOX, p<0.0001). With a median follow-up of 39 mos, 3263 DFS events were observed. Overall, the 3 year DFS rate was 74.6% (3m) and 75.5% (6m), with estimated DFS HR of 1.07 (95%CI, 1.00-1.15). The 3m v 6m DFS HRs were 1.16 (95%CI, 1.06-1.26) and 0.95 (95% CI, 0.85-1.06) for FOLFOX and XELOX treated pts, respectively. The 3m v 6m DFS HRs were 1.01 (95%CI, 0.90-1.12) in T1-3 N1, and 1.12 (95%CI, 1.03-1.23) for T4 or N2 pts. Conclusions: While NI was not established for the overall cohort, NI of 3m v 6m oxali-based adjuv therapy was supported for XELOX. As each IDEA trial treated varying proportions of pts with XELOX (0 to 75%), the regimen interaction likely produced the differential outcomes observed between individual studies. Certain substages (T1-3 N1) also showed NI for 3m v 6m. These data provide a framework for discussions on risks and benefits of individualized adjuv therapy approaches. Support: U10CA180821, U10CA180882, U10CA180888, U10CA180835, INCA, PHRC2009, EME 09/800/34, HTA 14/140/84, CRUK C1348/A15960, JFMC. Clinical trial information: NCT01150045.

Assessing outcome differences in the second line treatment of metastatic colorectal cancer (mCRC): An ARCAD analysis comparing sequence after first line trials (SAFL) and dedicated second line trials (DSLT)

3554

Background: There is considerable variability in the outcomes between second line (SL) trials in mCRC. The aim of this analysis is to compare the outcomes of patients (pts) with mCRC treated either on SAFL, with protocol defined SL treatment, or DSLT. Methods: Individual pt data was available on pts with mCRC enrolled in 1 of 10 trials (7 DSLT, 3 SAFL) in the ARCAD database. Regimens included FOLFIRI, FOLFOX, and irinotecan (IRI), since pts did not receive biologic agents in SL on SAFL. For pts on a SAFL, PFS and OS were defined as time from initiation of SL treatment to second progression (SP)/death and death, respectively. Descriptive statistics and multivariable Cox models were used to assess differences in PFS and OS. Results: 5,076 pts were included; 63% were male; median age was 62. See Table for treatment details. Pts treated on SAFL had shorter OS (0.7-1.5 months (mos>) shorter) and PFS (0.6-2.6 mos shorter), compared to those treated on DSLT. These findings were statistically significant and differences in OS did not attenuate after adjustment for age, gender, and prior treatment. PFS differences in FOLFOX became insignificant after multivariable adjustment. Conclusions: There are modest differences in both PFS and OS between pts with mCRC treated on SAFL and those on DSLT, suggesting differences in these pt populations. Caution is needed when applying these data to pts, as we were unable to control for potential confounders (ECOG PS, number and sites of metastases) at initiation of SL in SAFL, which may impact outcomes. [Table: see text]

FOLFOX4/XELOX in stage II–III colon cancer: Efficacy results of the Italian three or six colon adjuvant (TOSCA) trial

3501

Background: Six months of oxaliplatin-based treatment has been the standard of care as adjuvant therapy for stage III colon cancer and an accepted option for high-risk stage II. Given the cumulative neurotoxicity associated to oxaliplatin, a shorter duration of therapy, if equally efficacious, would be advantageous for patients and health-care systems. Methods: TOSCA was an open-label, phase III, multicenter, non-inferiority trial randomizing patients with high-risk stage II or stage III radically resected colon cancer to receive 3 months or 6 months of FOLFOX4/XELOX. Primary end-point was relapse-free survival. Results: From June 2007 to March 2013, 3759 patients were accrued from 130 Italian sites, 64% receiving FOLFOX4 and 36% XELOX in either arm. Two thirds were stage III. At the cut-off time for analysis the median time of follow-up was 62 months and 772 relapses or deaths have been observed. The RFS rate at 8 years is 75%. This analysis was done when 82% of the planned number of events was reached, with a power of 72% instead of 80%. The decision to anticipate the analysis was based on the participation to the IDEA joint collaborative analysis of studies sharing this clinical question. The Hazard Ratio of the 3months vs 6 months for relapse/death was 1.14 (95%CI 0.99-1.31, p for non inferiority = 0.253) and the confidence interval crossed the non inferiority limit of 1.20. Conclusions: TOSCA was not able to demonstrate that 3 months of oxaliplatin-based adjuvant treatment is as efficacious as 6 months. Nevertheless , because the absolute difference in RFS between the two treatment durations is small ( less than 3 % at 5 years ), the decision to complete the whole 6-month program should be individualized based on toxicity and patients’ attitude. This study is registered with ClinicalTrials.gov Registration Number: NCT00646607. It was supported by a grant from AIFA (Agenzia Italiana del Farmaco) Grant Code FARM5RWTWZ. Clinical trial information: NCT00646607.

Prospective pooled analysis of six phase III trials investigating duration of adjuvant (adjuv) oxaliplatin-based therapy (3 vs 6 months) for patients (pts) with stage III colon cancer (CC): The IDEA (International Duration Evaluation of Adjuvant chemotherapy) collaboration

LBA1

The full, final text of this abstract will be available at abstracts.asco.org at 7:30 AM (EDT) on Sunday, June 4, 2017, and in the Annual Meeting Proceedings online supplement to the June 20, 2017, issue of the Journal of Clinical Oncology. Onsite at the Meeting, this abstract will be printed in the Sunday edition of ASCO Daily News.

Radiological imaging markers predicting clinical outcome in patients with metastatic colorectal carcinoma treated with regorafenib: post hoc analysis of the CORRECT phase III trial (RadioCORRECT study)

OBJECTIVE

To identify imaging markers predicting clinical outcomes to regorafenib in metastatic colorectal carcinoma (mCRC).

METHODS

The RadioCORRECT study is a post hoc analysis of a cohort of patients with mCRC treated within the phase III placebo-controlled CORRECT trial of regorafenib. Baseline and week 8 contrast-enhanced CT were used to assess response by RECIST 1.1, changes in the sum of target lesion diameters (ΔSTL), lung metastases cavitation and liver metastases density. Primary and secondary objectives were to develop ex novo univariable and multivariable models to predict overall survival (OS) and progression-free survival (PFS), respectively.

RESULTS

202 patients were enrolled, 134 (66.3%) treated with regorafenib and 68 (33.7%) with placebo. In the univariate analysis, PFS predictors were lung metastases cavitation at baseline (HR 0.50, 95% CI 0.27 to 0.92, p=0.03) and at week 8 (HR 0.58, 95% CI 0.36 to 0.93, p=0.02). Baseline cavitation (HR 0.23, 95% CI 0.08 to 0.66, p=0.007), RECIST 1.1 (HR 0.23, 95% CI 0.14 to 0.4, p <0.0001) and ΔSTL (HR 1.16, 95% CI 1.06 to 1.27, p=0.002) predicted OS. We found an increase of 9% of diameter as the best threshold for discriminating OS (HR 2.64, 95% CI 1.61 to 4.34, p <0.001). In the multivariate analysis, baseline and week 8 cavitation remained significant PFS predictors. Baseline cavitation, RECIST 1.1 and ΔSTL remained predictors of OS in exploratory multivariable models. Assessment of liver metastases density did not predict clinical outcome.

CONCLUSIONS

RECIST 1.1 and ΔSTL predict favourable outcome to regorafenib. In contrast to liver metastases density that failed to be a predictor, lung metastases cavitation represents a novel radiological marker of favourable outcome that deserves consideration.

Onset of neutropenia as an indicator of treatment response in the phase 3 RECOURSE trial of trifluridine/tipiracil (TAS-102) versus placebo in patients with metastatic colorectal cancer

775

Background: TAS-102 is comprised of an antineoplastic thymidine-based nucleoside analog, trifluridine (FTD), and a thymidine phosphorylase inhibitor, tipiracil. Primary results of the RECOURSE trial demonstrated a significant improvement in overall survival (OS) and progression-free survival (PFS) with TAS-102 vs placebo (pbo) in patients (pts) with metastatic colorectal cancer refractory/intolerant to standard therapies. Neutropenia is a common TAS-102–associated adverse event and it has been hypothesized to be associated with a relatively high FTD concentration in pts. Methods: RECOURSE data were analyzed post hoc for correlations between onset of neutropenia (Grade 3/4) and survival benefit. Results: Of 533 pts given TAS-102, 75 (14%) developed Grade 3/4 neutropenia in treatment cycle 1, 86 (16%) for the first time in cycle 2, and 39 (7%) for the first time in cycle ≥3. Onset of neutropenia at any cycle was associated with longer median OS and PFS compared with no neutropenia. A consistent survival benefit was observed regardless of the cycle of initial onset of neutropenia, as demonstrated by the hazard ratio (against cycle-matched pbo control groups) and corresponding median OS differences (Table). Conclusions: An association between occurrence of earliest onset of Grade 3/4 neutropenia and survival benefit was observed. The data indicate that such survival benefit occurred regardless of whether the initial onset of neutropenia occurred after cycle 1, cycle 2, or later. Further analyses are required to fully determine whether FTD pharmacokinetics correlate with TAS-102 efficacy and onset of neutropenia, and whether cycle initiation delays affect response. Clinical trial information: NCT01607957. [Table: see text]

Nintedanib (N) plus best supportive care (BSC) versus placebo plus BSC for the treatment of patients (pts) with metastatic colorectal cancer (mCRC) refractory to standard therapies: Health-related quality of life (HRQoL) results of the Phase III LUME-Colon 1 study

671

Background: N is a multiple angiokinase inhibitor (including VEGFR, PDGFR and FGFR). A randomised Phase III study, LUME-Colon 1 (NCT02149108), evaluated the efficacy and safety of N in pts with refractory mCRC after failure of standard therapies. LUME-Colon 1 showed a statistically significant improvement in PFS (HR [95% CI] 0.58 [0.49–0.69]; p < 0.0001) but no difference in OS (HR [95% CI]: 1.01 [0.86–1.19]; p = 0.8659). Here, we report the HRQoL outcomes. Methods: 768 pts with mCRC adenocarcinoma refractory to standard chemotherapy were randomised 1:1 to receive either N (200 mg bid) + BSC or P (bid) + BSC in 21-day courses until disease progression or undue toxicity. HRQoL was assessed every 21 days using the EORTC QLQ-C30 instrument; the main endpoints of interest were the differences in mean scores up to median follow-up time (treatment difference, TD) for physical functioning (PF) and global health status/QoL (QL) scales using a longitudinal model, with 95% CIs and associated p-values adjusted for baseline stratification factors. Time to deterioration (TTD) of scores and status change ( ≥ 10 point change from baseline) were also assessed. Results: Compliance with questionnaire completion was high ( > 85% in first 12 cycles). Mean baseline (N vs P) PF (80 vs 80) and QL (65 vs 65) scale scores were balanced between treatment arms. The mean TD favoured N vs P for PF scale scores (TD 2.66 [95% CI: 0.97–4.34]; p = 0.0020) and QL scale scores (TD 1.61 [95% CI: −0.04–3.27]; p = 0.0555). TTD of PF (HR 0.84; 95% CI: 0.69–1.03; p = 0.0904) and QL (HR 0.90; 95% CI: 0.75–1.08; p = 0.2674) scores were not significantly different between treatment groups, although the percentage of patients with improved PF (17.2% vs 11.8%; p = 0.0462) and QL scores (30.3% vs 21.6%: p = 0.0102) were both significantly higher for N vs P. Conclusions: In LUME-Colon 1, patient reported outcomes confirmed that overall HRQoL was not impaired by treatment with N. There was evidence for improvement of PF and QL with N vs P, corresponding to the significant increase in PFS observed. Clinical trial information: NCT02149108.

Outcomes in the second line treatment of metastatic colorectal cancer (mCRC): Findings from 6,462 patients (pts) in the ARCAD database

757

Background: Progression free survival (PFS) and overall survival (OS) appear to differ across trials, even when pts receive the same regimen (REG). This analysis aimed to benchmark the clinical outcomes in the 2nd line treatment of metastatic colorectal cancer (mCRC). Methods: Individual patient (pt) data was available on 6,462 pts with mCRC enrolled in 7 2ndline clinical trials (8 REGs) in the ARCAD database. Regimens used in at least two trials included FOLFIRI +/- an EGFR inhibitor (EGFRi), FOLFOX +/- a VEGF inhibitor (VEGFi), and irinotecan (IRI). Descriptive statistics were used to describe pt demographics. Multivariable Cox models were used to assess differences (DIFFs) in PFS and OS, while p-value <0.05 were considered statistically significant (SS). Results: 500-1400 pts received each REG (see Table). Median OS and PFS differed by 0.2 to 4.6 months (mo) and 0.8 to 2.5 mo across trials within the same REG. These DIFFs were SS except for PFS in REGs containing FOLFIRI +/- EGFRi. After multivariable adjustment, all DIFFs in OS were attenuated and non-significant. DIFFs in PFS attenuated for most REGs but remained SS for FOLFOX and IRI. Conclusions: After multivariable adjustment, there were no SS DIFFs in outcomes across trials within the same REG, with the exception of PFS in FOLFOX and IRI. The initial observed DIFFs in outcomes could be due to confounding factors and the remaining SS DIFFs in PFS in FOLFOX and IRI may be due to variation in definition of progression across trials. Therefore, caution is warranted when using historical data to design future trials.[Table: see text]

Time-course evaluation of survival and treatment in FIRE-3 (AIO KRK0306, first-line therapy of KRAS wild-type metastatic colorectal cancer with FOLFIRI plus cetuximab or bevacizumab)

617

Background: FIRE-3 reported overall survival (OS) difference in favour of arm A (FOLFIRI plus cetuximab, N= 297 pts.) compared to arm B (FOLFIRI plus bevacizumab, N= 295 pts.) in the absence of significant differences in progression-free survival and response rate. Methods: We subdivided the study into six-month time intervals, starting at the time point of randomisation and evaluated OS in a time-wise fashion. Within each interval, OS was analyzed by Cox regression. Furthermore, systemic treatment and local interventions were investigated in the respective time-frames. Results: The time-course hazard ratios of OS are summarized in the Table. Pronounced differences in overall survival by time-interval analysis are observed between 24 and 30 months and between 30 and 36 months. Within the interval of 24-30 months, 24.6% (73/297) of pts in arm A and 25.1% (74/295) of pts in arm B received systemic therapy (any treatment-line). In the subsequent interval of 30-36 months, systemic anti-tumor treatment decreased to 18.9% (56/297) of pts in arm A and 16.3% (48/295) of pts in arm B. Median time on treatment was less than 2 months in the intervals of 24-30 months and 30-36 months. Updated data including RAS wild-type population will be presented at the meeting. Conclusions: The differences in OS observed in FIRE-3 are pronounced in time intervals between 24-30 months as well as 30-36 months after randomisation into the study. A small number of patients received rather short courses of anti-tumor therapy in these observation units. The significant difference in OS that manifests in time-frames between 24 and 30 months as well as between 30 and 36 months suggests that underlying effects on OS in FIRE-3 may include multiple factors and cannot be explained by the number of patients on active treatment alone. Clinical trial information: NCT00433927. [Table: see text]

TAS-102 versus placebo plus best supportive care in patients with metastatic colorectal cancer refractory to standard therapies: Final survival results of the phase III RECOURSE trial

634

Background: TAS-102 is comprised of an antineoplastic thymidine-based nucleoside analog, trifluridine, and a thymidine phosphorylase inhibitor, tipiracil hydrochloride. Efficacy and safety of TAS-102 in patients with metastatic colorectal cancer refractory/intolerant to standard therapies were evaluated in the RECOURSE trial. Original results of RECOURSE based on the cut-off date of January 24, 2014, in which 72% of mortality events had occurred, demonstrated a significant improvement in overall survival (OS) with TAS-102 vs placebo. Here we report results of an updated survival analysis from RECOURSE and a retrospective analysis of OS outcomes based on a clinical prognostic risk index. Methods: Patients were randomized 2:1 to receive TAS-102 or placebo. Study treatment continued until disease progression, death, or unacceptable toxicity. The primary endpoint was OS; final survival data were collected on October 8, 2014. A clinical OS prognostic risk score was assessed to evaluate OS effect in patients from low to high prognostic score. Prognostic factors contributing to the risk index were from those prespecified in the multivariate modeling assessment of OS outcome. Results: At data cut-off for the final survival analysis, 89% of the 800 patients randomly assigned to TAS-102 or placebo had died, accounting for 138 events in addition to 574 (72%) events included in the original analysis. The updated results for OS are shown in the Table. Conclusions: An updated survival analysis confirmed that OS benefit with TAS-102 was maintained and increased to a full 2 months; improvement in 1-year survival surpassed 10% in these heavily pretreated patients. OS benefit appears to be maintained for all patients in the trial regardless of prognostic status at trial entry. Clinical trial information: NCT01607957. [Table: see text]

Phase III RECOURSE trial of TAS-102 versus placebo with best supportive care in patients with metastatic colorectal cancer: Geographic subgroups

646

Background: TAS-102 is comprised of an antineoplastic thymidine-based nucleoside analog, trifluridine, and the thymidine phosphorylase inhibitor, tipiracil hydrochloride, at a molar ratio of 1:0.5 (weight ratio, 1:0.471). The efficacy and safety of TAS-102 in patients (pts) with metastatic colorectal cancer refractory/intolerant to standard therapies were evaluated in the RECOURSE trial; enrollment criteria included ≥ 2 prior lines of standard chemotherapy. Primary results of RECOURSE demonstrated a significant improvement in overall survival (OS) and progression-free survival (PFS) with TAS-102 vs placebo (PBO) (hazard ratio [HR] = 0.68 and 0.48 for OS and PFS, respectively; both P< 0.0001). Methods: RECOURSE data were evaluated for efficacy and safety, including rate of hospitalizations, of TAS-102 vs PBO by each geographic subgroup of US, EU, and Japan (JP). Results: Of 768 pts, 99 US (mean age, 60 y), 403 EU (mean age, 62 y), and 266 JP (mean age, 62 y) pts were randomized to receive TAS-102 or PBO. Median OS with TAS-102 vs PBO was 6.5 mo vs 4.3 mo in US pts, 6.8 mo vs 4.9 mo in EU pts, and 7.8 mo vs 6.7 mo in JP pts. HRs for OS and PFS for US, EU, and JP pts all favored TAS-102 (Table). There were no marked differences among the US, EU, and JP subgroups with respect to overall incidence of adverse events (AEs), ≥ Grade 3 AEs, serious AEs (SAEs), or hospitalizations. Conclusions: Similar to the overall RECOURSE population, OS and PFS benefits were observed in each geographic subgroup randomized to TAS-102 vs PBO, with an acceptable safety profile. Clinical trial information: NCT01607957. [Table: see text] [Table: see text]

TAS-102 versus placebo (PBO) in patients (pts) ≥65 years (y) with metastatic colorectal cancer (mCRC): An age-based analysis of the recourse trial

638

Background: TAS-102 is comprised of an antineoplastic thymidine-based nucleoside analog, trifluridine, and the thymidine phosphorylase inhibitor, tipiracil hydrochloride, at a molar ratio of 1:0.5 (weight ratio, 1:0.471). Efficacy and safety of TAS-102 in pts with mCRC refractory to standard therapies were evaluated in the RECOURSE trial; enrollment criteria included ≥2 prior lines of standard chemotherapy. Primary results of RECOURSE demonstrated a significant improvement in overall survival (OS) (TAS-102 7.1 mo vs PBO 5.3 mo; HR=0.68; P<0.0001) and progression-free survival (PFS) (HR=0.48; P<0.0001). Methods: This prespecified analysis compared the efficacy and safety of TAS-102 vs PBO in pts ≥65 y and <65 y with mCRC. A retrospective analysis of pts ≥75 y was also performed. Results: Of 800 randomized pts, 352 (44.0%) were ≥65 y and 60 (7.5%) were ≥75 y. Median OS in pts ≥65 y was 7.0 mo with TAS-102 vs 4.6 mo with PBO (HR=0.62, 95% CI: 0.48-0.80, P=0.0002). PFS HR was 0.41 (95% CI: 0.32-0.52, P<0.0001) for pts ≥65 y, also favoring TAS-102. In pts ≥65 y, disease control rate (complete or partial response or stable disease) was 48.7% with TAS-102 vs 15.5% with PBO. An age-related difference in overall incidence of adverse events (AEs) was not observed in either treatment arm. Treatment-related AEs, ≥ Grade 3 AEs, and severe AEs were generally more common in pts ≥65 y than in pts <65 y (Table). Mean drug exposure was similar among pts ≥65 y and ≥75 y, as was overall safety profile. Conclusions: Significant improvements in OS and PFS were observed in pts ≥65 y who received TAS-102 vs PBO, with a mild increase in toxicity. Pts ≥65 y and <65 y showed a generally favorable safety profile. A significant increase in toxicity in pts ≥75 y was not apparent vs the overall ≥65 y population. Clinical trial information: NCT01607957. [Table: see text]

Immunomodulatory switch maintenance therapy in metastatic colorectal carcinoma: The phase III IMPALA study

TPS785

Background: The Toll-like receptor 9 agonist MGN1703 was compared to placebo in 59 metastatic CRC (mCRC) patients with disease control after standard induction chemotherapy in the double-blind randomized phase 2 IMPACT study. MGN1703 showed a superior effect over placebo, with a hazard ratio (HR) for the primary endpoint “PFS on maintenance” of 0.55 (p = 0.041) by local assessment and 0.56 (p = 0.070) by independent radiological review. Exploratory PFS analyses identified patients with objective RECIST response, normalized CEA and presence of activated NKT cells at the end of induction treatment to benefit the most from MGN1703. The OS evaluation showed a HR of 0.40 (median 24.5 vs. 15.1 months) for patients with RECIST response after induction therapy. Furthermore, at time of IMPACT study closure, 4 MGN1703 patients were still without progressive disease and continued treatment in compassionate use. As of August 2015, 3 patients were still receiving MGN1703 treatment in excess of three years (47-55 months), with 2 objective responses ongoing over 46 months. Methods: The international, multicenter, open-label phase 3 IMPALA study is conducted in collaboration with the AIO, TTD and GERCOR cooperative groups. In IMPALA, mCRC patients having achieved an objective tumor response following any type of first line induction therapy are randomized to receive MGN1703 switch maintenance monotherapy in the experimental arm or local standard of care in the control arm. In case of relapse, patients will reintroduce induction treatment whenever feasible, with those in the experimental arm continuing to receive MGN1703 therapy in the weeks without infusional chemotherapy. The primary endpoint of the study will be OS. Secondary endpoints include PFS, response rates, safety, and QoL in selected centers. Induction treatment, CEA and activated NKT at baseline are stratification factors and will be prospectively assessed. All randomized patients take part in a comprehensive immune monitoring plan evaluating cytokines and chemokines in serum and the activation status of immune cell populations. Recruitment started in September 2014 and the study is expected to recruit 540 patients within 24 months in 8 European countries. Clinical trial information: NCT02077868.

LAPACT: An open-label, multicenter phase II trial of nab-paclitaxel (nab-P) plus gemcitabine (Gem) in patients (pts) with locally advanced pancreatic cancer (LAPC)

TPS477

Background: In pts with LAPC, more effective systemic therapies may be associated with improved local control, delay of metastasis, and overall survival (OS). The phase III MPACT trial in pts with metastatic PC demonstrated longer OS (median, 8.7 vs 6.6 mos; HR, 0.72; P < 0.001) and an ≈ 3-fold greater shrinkage of primary tumors with nab-P + Gem vs Gem alone (−22.15% vs −7.02%), raising the possibility of improved local PC control with nab-P + Gem. LAPACT will assess the efficacy and safety of nab-P + Gem in LAPC. Methods: LAPACT will enroll treatment-naive pts (planned n ≈ 110) in the United States, Canada, and Europe with Eastern Cooperative Oncology Group performance status ≤ 1, confirmed unresectable LAPC, no distant metastases, and adequate organ function. Pts with mixed-origin tumors, any other malignancy within 5 years, peripheral neuropathy grade > 1, or clinically significant ascites are ineligible. Pts will receive nab-P 125 mg/m2 + Gem 1000 mg/m2 on days 1, 8, and 15 of each 28-day cycle. Pts without progressive disease (PD) or unacceptable toxicity after 6 cycles will receive investigator’s choice of surgery, chemoradiotherapy, or continued nab-P + Gem. If a major response is observed, surgery may occur prior to completing 6 cycles of nab-P + Gem. The primary endpoint is time to treatment failure (TTF; time from first therapy dose to discontinuation due to PD, start of a new non–protocol-defined anti-cancer therapy, or death). The study design allows for 80% power at a 1-sided α of 0.05 to detect a 30% increase over the 5.1-month median TTF observed for nab-P + Gem in the MPACT study. The secondary endpoints are disease control rate (DCR) after 6 cycles, overall response rate, progression-free survival, OS, safety, and quality of life. The exploratory endpoint is correlation of changes in circulating nucleic acids with PD and treatment response. An interim DCR analysis will occur after all pts have completed 6 cycles of nab-P + Gem, discontinued therapy due to PD, died, or started a new non–protocol-defined therapy before completing 6 cycles of therapy. Enrollment is ongoing (first pt enrolled in April 2015). Clinical trial information: NCT02301143.

Analysis of KRAS/NRAS Mutations in a Phase III Study of Panitumumab with FOLFIRI Compared with FOLFIRI Alone as Second-line Treatment for Metastatic Colorectal Cancer

PURPOSE

We evaluated the influence of RAS mutation status on the treatment effect of panitumumab in a prospective-retrospective analysis of a randomized, multicenter phase III study of panitumumab plus fluorouracil, leucovorin, and irinotecan (FOLFIRI) versus FOLFIRI alone as second-line therapy in patients with metastatic colorectal cancer (mCRC; ClinicalTrials.gov, NCT0039183).

EXPERIMENTAL DESIGN

Outcomes were from the study's primary analysis. RAS mutations beyond KRAS exon 2 (KRAS exons 3, 4; NRAS exons 2, 3, 4; BRAF exon 15) were detected by bidirectional Sanger sequencing in wild-type KRAS exon 2 tumor specimens. Progression-free survival (PFS) and overall survival (OS) were coprimary endpoints.

RESULTS

The RAS ascertainment rate was 85%; 18% of wild-type KRAS exon 2 tumors harbored other RAS mutations. For PFS and OS, the hazard ratio (HR) for panitumumab plus FOLFIRI versus FOLFIRI alone more strongly favored panitumumab in the wild-type RAS population than in the wild-type KRAS exon 2 population [PFS HR, 0.70 (95% confidence interval [CI], 0.54-0.91); P = 0.007 vs. 0.73 (95% CI, 0.59-0.90); P = 0.004; OS HR, 0.81 (95% CI, 0.63-1.03); P = 0.08 vs. 0.85 (95% CI, 0.70-1.04); P = 0.12]. Patients with RAS mutations were unlikely to benefit from panitumumab. Among RAS wild-type patients, the objective response rate was 41% in the panitumumab-FOLFIRI group versus 10% in the FOLFIRI group.

CONCLUSIONS

Patients with RAS mutations were unlikely to benefit from panitumumab-FOLFIRI and the benefit-risk of panitumumab-FOLFIRI was improved in the wild-type RAS population compared with the wild-type KRAS exon 2 population. These findings support RAS testing for patients with mCRC. Clin Cancer Res; 21(24); 5469-79. ©2015 AACR.See related commentary by Salazar and Ciardiello, p. 5415.

Ziv-aflibercept (Z) in combination with FOLFIRI for second-line treatment of patients with metastatic colorectal cancer (mCRC): Interim safety data from the global Aflibercept Safety and Quality-of-Life Program (ASQoP and AFEQT) in patients age 65 or older

588

Background: The prespecified analysis of patients (pts) ≥65 y in the VELOUR study demonstrated a safety profile similar to that of ziv-aflibercept (Z) (known as aflibercept outside the United States) plus FOLFIRI in the overall VELOUR population. The global ASQoP/AFEQT Program comprises 2 clinical studies (ASQoP [NCT01571284]; AFEQT [NCT01670721]) designed to capture QoL and safety data from a population similar to VELOUR but treated in a real-life setting. We report safety data from the fourth interim analysis of pts ≥65 y. Methods: ASQoP/AFEQT are single-arm, open-label trials evaluating Z in metastatic colorectal cancer pts previously treated with an oxaliplatin-containing regimen. Eligible pts received Z (4 mg/kg) q2w on day 1 of each cycle followed by FOLFIRI until disease progression, unacceptable toxicity, death, or investigator/pt decision. Initial starting doses of FOLFIRI and dose modifications are at treating physician’s discretion. The % of pts ≥65 y with grade (G) 3 or 4 AEs in the combined safety population of ASQoP/AFEQT are compared with the prespecified analysis in pts ≥65 y from the Z + FOLFIRI arm of VELOUR. Results: At data cutoff, the overall safety population comprised 688 pts with ≥1 completed treatment cycle; 303 (44.1%) were ≥65 y. In the overall safety population ≥1 G3/4 AE was reported in 72.2% of pts vs. 83.5% in overall VELOUR. Most G3/4 AEs were G3. There were no reports of G4 hypertension, diarrhea, or fatigue. Median number of cycles was 6 in ASQoP/AFEQT and 9 in the Z + FOLFIRI arm of VELOUR. Table shows summary of AEs in pts ≥65 y. Conclusions: This interim analysis from ASQoP/AFEQT in pts ≥65 y has identified no new safety signals and provides additional safety data suggesting an acceptable toxicity profile in this real-life setting. Clinical trial information: NCT01571284. [Table: see text]

Ziv-aflibercept (Z) in combination with FOLFIRI for second-line treatment of patients (pts) with metastatic colorectal cancer (mCRC): Interim safety data from the global Aflibercept Safety and Quality-of-Life Program in pts pretreated with bevacizumab (B)

528

Background: In the VELOUR study, adding ziv-aflibercept (Z) (known as aflibercept outside the United States) to FOLFIRI resulted in improved OS, PFS, and RR in metastatic colorectal cancer (mCRC) patients (pts) who had received prior oxaliplatin. Prior treatment with bevacizumab (B) did not appear to impact safety profile of Z. The global ASQoP/AFEQT studies are 2 clinical studies (ASQoP [NCT01571284]; AFEQT [NCT01670721]) designed to capture QoL and safety data from a population similar to VELOUR but treated in a real-life setting. We report safety data from the 4th interim analysis in B-pretreated pts. Methods: ASQoP/AFEQT are single-arm, open-label trials of Z in mCRC pts previously treated with an oxaliplatin-containing regimen. Eligible pts receive Z (4 mg/kg) q2w on day 1 of each cycle followed by FOLFIRI until disease progression, unacceptable toxicity, death, or investigator/pt decision. Initial starting doses of FOLFIRI and subsequent modifications are at treating physician’s discretion. % of pts with grade (G) 3 or 4 AEs in the combined B-pretreated safety population of ASQoP/AFEQT is compared with B-pretreated pts in the Z + FOLFIRI arm of VELOUR. Results: At data cutoff, overall safety population comprised 688 pts with ≥1 completed treatment cycle; 343 (49.9%) were B-pretreated. Currently, median number of cycles administered to ASQoP/AFEQT pts is 6; in VELOUR, pts in Z + FOLFIRI arm had a median of 9. Table shows summary of TEAEs in B-pretreated pts. Conclusions: Thisinterim safety analysis of ASQoP/AFEQT in B-pretreated pts identified no new safety signals for Z and a trend toward decreased G3/4 events. The analysis provides additional safety data suggesting an acceptable toxicity profile in a real-life setting. Clinical trial information: NCT01571284. [Table: see text]