Phase II study of reintroduction of oxaliplatin for advanced colorectal cancer in patients previously treated with oxaliplatin and irinotecan: RE-OPEN study

Third-line treatment and beyond in metastatic colorectal cancer: What do we have and what can we expect?

Colorectal cancer remains the third most common cancer worldwide and the second cause of cancer-related death. Treatment advances and precision oncological medicine for these tumours have been stalled in comparison to those for other common tumours such as lung and breast cancer. However, the recent publication of the SUNLIGHT trial results with the trifluridine/tipiracil (TAS-102)-bevacizumab combination and the irruption of new molecular targets with guided treatments have opened new possibilities in third-line metastatic colorectal cancer management. Anti-EGFR rechallenge, anti-HER2 targeted therapies or the promising results of Pressurised Intraperitoneal Aerosol Chemotherapy (PIPAC), are some of the available options that may modify what is presumably third-line colorectal treatment. Hereby, we present the evidence of the different treatment options in third-line colorectal cancer and beyond, as well as the possibilities of sequencing them.

Chemotherapy Rechallenge or Reintroduction Compared to Regorafenib or Trifluridine/Tipiracil for Pretreated Metastatic Colorectal Cancer Patients: A Propensity Score Analysis of Treatment Beyond Second Line (Proserpyna Study)

BACKGROUND

The optimal treatment for metastatic colorectal cancer (mCRC) beyond second line is still questioned. Besides the standard of care agents (regorafenib, REG, or trifluridine/tipiracil, FTD/TPI), chemotherapy rechallenge or reintroduction (CTr/r) are commonly considered in clinical practice, despite weak supporting evidence. The prognostic performance of CTr/r, REG and FTD/TPI in this setting are herein evaluated.

PATIENTS AND METHODS

PROSERpYNa is a multicenter, observational, retrospective study, in which patients with refractory mCRC, progressing after at least 2 lines of CT, treated with CTr/r, REG or FTD/TPI, are considered eligible and were enrolled in 2 independent data sets (exploratory and validation). Primary endpoint was overall survival (OS); secondary endpoints were investigator-assessed progression-free survival (PFS), objective response rate (RR) and safety. A propensity score adjustment was accomplished for survival analyses.

RESULTS

Data referring to patients treated between Jan-10 and Jan-19 from 3 Italian institutions were gathered (341 and 181 treatments for exploratory and validation data sets respectively). In the exploratory cohort, median OS (18.5 vs. 6.5 months), PFS (6.1 vs. 3.5 months) and RR (28.6% vs. 1.4%) were significantly longer for CTr/r compared to REG/FTD/TPI. Survival benefits were retained at the propensity score analysis, adjusted for independent prognostic factors identified at multivariate analysis. Moreover, these results were confirmed within the validation cohort analyses.

CONCLUSIONS

Although the retrospective fashion, CTr/r proved to be a valuable option in this setting in a real-world context, providing superior outcomes compared to standard of care agents at the price of a moderate toxicity.

The salvage lenvatinib-based regimen provides survival benefit in patients with refractory metastatic colorectal cancer

Salvage treatment for refractory metastatic colorectal cancer (mCRC) has yet to be identified. We aimed to evaluate the efficacy of a salvage lenvatinib-based regimen for refractory mCRC. In total, 371 patients were categorized into lenvatinib-based and non-lenvatinib-based groups. In the lenvatinib-based group, patients who received lenvatinib at a dosage of 10 mg/day were categorized into lenvatinib/chemotherapy and lenvatinib/immunotherapy subgroups. We reported overall survival (OS) and progression-free survival (PFS) using the Kaplan-Meier method. OS1 was used to measure the time from disease progression after TAS-102 and regorafenib treatment to death, while OS2 was used to measure the time from TAS-102 or regorafenib treatment to death. Propensity score matching analysis was employed to compare the characteristics between the lenvatinib-based and non-lenvatinib-based groups. Next-generation sequencing (NGS) information was analyzed using R software. The lenvatinib-based group exhibited longer OS than did the non-lenvatinib-based group (OS1, 11.4 vs. 3.7 months; OS2, 27.2 vs. 8.2 months). The disease control rate (DCR) and objective response rate (ORR) of the lenvatinib-based regimens were 69.4% and 6.1%, respectively. Lenvatinib/chemotherapy and lenvatinib/immunotherapy had similar PFS, OS, DCR, and ORR. The adverse effects were manageable. After propensity score matching, the lenvatinib-based group continued to exhibit significantly longer OS1 and OS2 than did the non-lenvatinib-based group. NGS analysis revealed that GNAS and KRAS alterations were associated with a worse treatment response and prolonged survival, respectively. In conclusion, a moderate-dose salvage lenvatinib-based regimen demonstrated promising clinical activity and tolerability in treating refractory mCRC.

Chemotherapy re-use versus anti-angiogenic monotherapy as the third-line treatment of patients with metastatic colorectal cancer: a real-world cohort study

BACKGROUND

There are various recommendations for third-line treatment in mCRC, however, there is no consensus on who is more suitable for particular strategy. Chemotherapy re-use in third-line setting is a common option in clinical practice. This study aimed to investigate the efficacy of third-line chemotherapy re-use by the comparison with that of anti-angiogenic monotherapy, and further find the population more suitable for third-line chemotherapy.

METHODS

Using electronic medical records of patients with mCRC, a retrospective cohort study was conducted. A total of 143 patients receiving chemotherapy and 40 patients receiving anti-angiogenic monotherapy in third-line setting as control group were retrospectively collected. Baseline characteristics were analyzed using the χ² test or the Fisher's exact test. ROC curve and surv_cutpoint function of 'survminer' package in R software were used to calculate the cut-off value. Survival curves were plotted with the Kaplan-Meier method and were compared using the log-rank test. The Cox proportional hazard regression model was used to analyze the potential risk factors.

RESULTS

A total of 143 patients receiving chemotherapy and 40 patients receiving anti-angiogenic monotherapy in third-line setting were retrospectively collected. Chemotherapy rechallenge was recorded in 93 patients (93/143, 65.0%), and the remaining patients chose new chemotherapeutic drugs that had not been previously used, including irinotecan-based (22/50), oxaliplatin-based (9/50), raltitrexed (9/50), gemcitabine (5/50) and other agents (5/50). The ORR and DCR of third-line chemotherapy reached 8.8%, 61.3%, respectively (anti-angiogenic monotherapy group: ORR 2.6%, DCR 47.4%). The mPFS and mOS of patients receiving chemotherapy were 4.9 and 12.0 m, respectively (anti-angiogenic monotherapy group: mPFS 2.7 m, mOS 5.2 m). Subgroup analyses found that patients with RAS/RAF mutation, longer PFS (greater than 10.6 m) in front-line treatment or larger tumor burden had better prognosis with third-line chemotherapy rather than anti-angiogenic monotherapy.

CONCLUSIONS

Third-line chemotherapy re-use was effective in mCRC. Those with more aggressive characteristics (RAS/RAF mutant, larger tumor burden) or better efficacy of previous chemotherapy (longer PFS) were more appropriate for third-line chemotherapy, rather than anti-angiogenic monotherapy.

Efficacy of Chemotherapy Rechallenge Versus Regorafenib or Trifluridine/Tipiracil in Third-Line Setting of Metastatic Colorectal Cancer: A Multicenter Retrospective Comparative Study

PURPOSE

Metastatic colorectal cancer (mCRC) is a significant global health burden. This retrospective study compared the effectiveness of trifluridine/tipiracil (FTD/TPI), regorafenib, and chemotherapy rechallenge for third-line mCRC treatment.

MATERIALS AND METHODS

We reviewed the medical records of 132 patients with mCRC treated with regorafenib, FTD/TPI, or a rechallenge with the initial chemotherapy regimen in a third-line setting from four different institutions. The primary end point was progression-free survival (PFS). Secondary end points were objective response rate and overall survival (OS) across the three treatment approaches.

RESULTS

Twenty-nine patients received chemotherapy rechallenge, and 103 received FTD/TPI or regorafenib. Patients' characteristics were comparable, except for a lower number of left-sided primaries and KRAS wild-type tumors in the FTD/TPI-regorafenib group. The median PFS for the entire group was 3.0 months, and the median OS was 13.7 months. Chemotherapy rechallenge has resulted in a median PFS of 3.1 months and a median OS of 21.2 months, compared with 2.9 months (PFS) and 12.6 months (OS) for the FTD/TPI-regorafenib group. Multivariate analyses identified male sex and an Eastern Cooperative Oncology Group performance status (ECOG PS) of 0-1 as independent prognostic factors for better PFS, whereas chemotherapy rechallenge, localized stage at diagnosis, and an ECOG PS of 0-1 were significant prognostic factors for better OS.

CONCLUSION

This study suggests that chemotherapy rechallenge may provide a survival benefit in the third-line treatment of mCRC. However, patient characteristics, such as sex and ECOG PS, should also be considered in treatment decisions. Further prospective studies are required to confirm our findings.

Comparing the efficacy of regorafenib and 5-fluorouracil-based rechallenge chemotherapy in the third-line treatment of metastatic colorectal cancer

BACKGROUND

The optimal treatment for metastatic colorectal cancer (mCRC) after the second line is still controversial. Regorafenib has been the standard of care in this setting as it improved overall survival (OS) compared to placebo. In real-world practice chemotherapy rechallenge is also a preferred option even though supporting evidence is not enough. We aim to compare the efficacy of regorafenib and 5-fluorouracil-based (5-FU) rechallenge treatment in the third line setting of mCRC.

METHODS

In this retrospective multi-institutional trial, mCRC patients from 21 oncology centers who progressed after 2 lines of chemotherapy were analyzed. Patients who were treated with regorafenib or rechallenge therapy in the third-line setting were eligible. Rechallenge chemotherapy was identified as the re-use of the 5-FU based regimen which was administered in one of the previous treatment lines. OS, disease control rate (DCR), progression free survival (PFS) and toxicity were analyzed.

RESULTS

Three hundred ninety-four mCRC patients were included in the study. 128 (32.5%) were in the rechallenge, and 266 (67.5%) were in the regorafenib group. Median PFS was 5.82 months in rechallenge and 4 months in regorafenib arms (hazard ratio:1.45,95% CI, p = 0.167). DCR was higher in the rechallenge group than regorafenib (77% vs 49.5%, respectively, p =  < 0.001). Median OS after the third-line treatment was 11.99 (95% CI, 9.49-14.49) and 8.08 months (95% CI, 6.88-9.29) for rechallenge and regorafenib groups, respectively (hazard ratio:1.51, 95% CI, p < 0.001). More adverse effects and discontinuation were seen with regorafenib treatment.

CONCLUSION

Our study revealed that higher disease control and OS rates were achieved with rechallenge treatment compared to regorafenib, especially in patients who achieved disease control in one of the first two lines of therapy.

Fecal microbiota transplantation plus tislelizumab and fruquintinib in refractory microsatellite stable metastatic colorectal cancer: an open-label, single-arm, phase II trial (RENMIN-215)

Background

Immunotherapy has revolutionized the treatment of cancer. However, microsatellite stable (MSS) metastatic colorectal cancer (mCRC) shows a low response to PD-1 inhibitors. Antiangiogenic therapy can enhance anti-PD-1 efficacy, but it still cannot meet clinical needs. Increasing evidence supported a close relationship between gut microbiome and anti-PD-1 efficacy. This study aimed to explore the efficacy and safety of the combination of fecal microbiota transplantation (FMT) and tislelizumab and fruquintinib in refractory MSS mCRC.

Methods

In the phase II trial, MSS mCRC patients were administered FMT plus tislelizumab and fruquintinib as a third-line or above treatment. The primary endpoint was progression-free survival (PFS). Secondary endpoints were overall survival (OS), objective response rate (ORR), disease control rate (DCR), duration of response (DoR), clinical benefit rate (CBR), safety and quality of life. Feces and peripheral blood were collected for exploratory biomarker analysis. This study is registered with Chictr.org.cn, identifier ChiCTR2100046768.

Findings

From May 10, 2021 to January 17, 2022, 20 patients were enrolled. Median follow-up was 13.7 months. Median PFS was 9.6 months (95% CI 4.1-15.1). Median OS was 13.7 months (95% CI 9.3-17.7). Median DoR was 8.1 months (95% CI 1.7-10.6). ORR was 20% (95% CI 5.7-43.7). DCR was 95% (95% CI 75.1-99.9). CBR was 60% (95% CI 36.1-80.9). Nineteen patients (95%) experienced at least one treatment-related adverse event (TRAE). Six patients (30%) had grade 3-4 TRAEs, with the most common being albuminuria (10%), urine occult blood (10%), fecal occult blood (10%), hypertension (5%), hyperglycemia (5%), liver dysfunction (5%), hand-foot skin reaction (5%), and hypothyroidism (5%). No treatment-related deaths occurred. Responders had a high-abundance of Proteobacteria and Lachnospiraceae family and a low-abundance of Actinobacteriota and Bifidobacterium. The treatment did not change the structure of peripheral blood TCR repertoire. However, the expanded TCRs exhibited the characteristics of antigen-driven responses in responders.

Interpretation

FMT plus tislelizumab and fruquintinib as third-line or above treatment showed improved survival and manageable safety in refractory MSS mCRC, suggesting a valuable new treatment option for this patient population.

Funding

This study was supported by the National Natural Science Foundation of China (82102954 to Wensi Zhao) and the Special Project of Central Government for Local Science and Technology Development of Hubei Province (ZYYD2020000169 to Yongshun Chen).

[Metastatic colorectal cancer-Modern treatment strategies and sequences]

The treatment of metastatic colorectal cancer (mCRC) has been considerably expanded and relevantly improved in recent years with new strategies, such as resection of liver and/or lung metastases, induction and maintenance treatment, the establishment of targeted therapies and molecularly defined strategies in defined subgroups. This article presents evidence-based treatment options and algorithms, with a focus on systemic treatment.

Clinical Outcomes of Everolimus Rechallenge in Patients with Pancreatic Neuroendocrine Neoplasms with No Other Treatment Options

BACKGROUND

The clinical outcomes of everolimus rechallenge in patients with pancreatic neuroendocrine neoplasms (PNENs) are unknown. This study aimed to investigate the treatment outcomes and safety of everolimus rechallenge treatment with PNENs.

METHODS

Clinical data of everolimus-treated patients with PNENs at two institutions were collected. Patients who underwent everolimus rechallenge were included in the study. We analyzed the progression-free survival (PFS) and treatment response associated with everolimus rechallenge and the adverse events.

RESULTS

Between 2008 and 2020, 117 patients received initial treatment with everolimus, of which 14 patients received everolimus rechallenge. With regard to the grade of PNENs, there were 2 cases of G1, 11 cases of G2, and 1 case of G3. The median rechallenge PFS was 5.7 months. The objective response rate was 21.4%. the disease control rate was 71.4%. The only major grade 3 or 4 adverse event was neutropenia (n = 1, 7.1%). No other severe adverse event was observed.

CONCLUSION

The outcomes and safety of everolimus rechallenge were verified, and it was deemed an acceptable treatment. Everolimus rechallenge may provide a new drug therapy for patients with advanced PNENs for whom no other drug treatment option is available.

Phase I Dose-Escalation Trial of an Innovative Chemotherapy Regimen Combining a Fractionated Dose of Irinotecan Plus Bevacizumab, Oxaliplatin, 5-Fluorouracil, and Folinic Acid (bFOLFIRINOX-3) in Chemorefractory Metastatic Colorectal Cancer

Simple Summary

Treatment of non-resectable metastatic colorectal cancer (mCRC) involves chemotherapy based on 5-fluorouracil, oxaliplatin and irinotecan and monoclonal antibodies targeting VEGF or EGFR. After an initial progression, it is usual to change the chemotherapy regimen and targeted therapy, with rather moderate results. Several studies have focused on the interest of using again already used molecules and rechallenge with oxaliplatin and irinotecan bi fractionation (FOLFIRI3) have previously shown efficacy in chemorefractory patients, but desynchronized triplet chemotherapy was never tested. The aim of this study was to evaluate the safety and efficacy of a new regimen so-called: FOLFIRINOX-3 bevacizumab in chemorefractory metastatic colorectal cancer.

Abstract

The care of metastatic colorectal cancers is based on combination chemotherapies including 5-fluorouracil, oxaliplatin, irinotecan, and monoclonal antibodies targeting the epidermal growth factor receptor or vascular endothelial growth factor. The regimen is determined based on the patient’s molecular biology and general condition. Irinotecan bifractionation showed efficacy in chemorefractory patients in a previous study, FOLFIRI-3, but a desynchronized triplet has never been tested. The aim of bFOLFIRINOX-3 is to determine the safety, tolerance, and efficacy of a new regimen (FOLFIRINOX-3 bevacizumab) in chemorefractory patients. The aim of this study was to evaluate the safety and efficacy of FOLFIRINOX-3 bevacizumab in chemorefractory metastatic colorectal cancer (mCRC). A standard phase I, “3 + 3” design study was performed. The standard protocol comprised simplified FOLFOX 4 (folinic acid 400 mg/m²), 5-fluorouracil (a 400 mg/m² bolus followed by 2400 mg/m² for 46 h), oxaliplatin (85 mg/m²) and irinotecan (administered before and after 5-fluorouracil infusion), plus bevacizumab (5 mg/kg). In a “3 + 3” design, three different doses of irinotecan were tested: 60, 70 and 90 mg/m². The primary endpoint was the maximum tolerable dose (MTD) of irinotecan. The secondary endpoints included the objective response (at 8 and 16 weeks) according to the RECIST 1.1 criteria and progression free survival. Thirteen patients were enrolled, and twelve patients were finally evaluated for dose-limiting toxicity (DLT). The dose level defined was 70 mg/m² irinotecan. A total of three DLTs were observed (grade 3 diarrhea): two DLTs at the 90 mg/m² dose level and one at the 70 mg/m² dose level. The most frequently described adverse events were asthenia (93%), diarrhea (77%), nausea (62%) and peripheral sensory neuropathy (46%). The most frequent biological event was thrombopenia (54%). Regarding efficacy, among the 11 evaluable patients, no progression was observed at 8 weeks, and the partial response rate was 18.2%. At 16 weeks, a partial response rate of 27.3% was observed, and five patients had a stable disease. The new regimen of bFOLFIRINOX-3 with irinotecan at 70 mg/m² was well tolerated. In chemorefractory patients, this protocol shows a high response rate.

Continuing Cetuximab vs Bevacizumab plus chemotherapy after first progression in wild-type KRAS, NRAS and BRAF V600E metastatic colorectal cancer: a randomized phase II trial

To evaluate the clinical efficacy of continuing cetuximab vs bevacizumab plus chemotherapy crossover after first progression to cetuximab regimen in wild-type KRAS, NRAS and BRAF V600E mCRC, we conducted this prospective, open-label and randomized phase 2 trial in three cancer centers from Oct 1, 2016 to July 1, 2020. Eligibility criteria included documented progressive disease during or after first-line treatment with cetuximab regimen; second biopsy confirmed as KRAS, NRAS and BRAF V600E wild-type mCRC. Patients were randomized to arm A (cetuximab+chemo) or arm B (bevacizumab+chemo) with second-line chemotherapy crossover. The primary end point was progression free survival (PFS). Secondary end points included objective response rate (ORR), overall survival (OS) and toxicity. Tissue VEGFA, ERBB2 and MET mRNA were examined by real time RT-PCR. A total of 104 patients (53 in arm A and 51 in arm B) were enrolled. Median PFS was 7.7 months (95% CI: 6.5-8.9) for arm A and 6.3 months (95% CI: 4.5-8.1) for arm B (p=0.931). Median OS was 18.2 months (95% CI: 14.5-21.9) for arm A and 16.4 months (95% CI: 14.2-18.6) for arm B (p=0.339). The ORR was 28.3% and 19.6% in arm A and arm B (p=0.31), respectively. MET mRNA was highly expressed in the cetuximab-progressed tumors, but treatment responsiveness to cetuximab or bevacizumab in each arm was not correlated with the MET expression level. The results showed no significant difference in PFS, OS and ORR between the two arms, but a trend in favor of the cetuximab continuation plus chemotherapy crossover was examined in all end points. High expression of MET in cetuximab-progressed tumors may indicate an existence of MET-dependent tumor cell population.

Patient demographics and management landscape of metastatic colorectal cancer in the third-line setting: Real-world data in an australian population

BACKGROUND

Colorectal cancer is the third most common cancer and second leading cause of cancer mortality in Australia, thus carrying a significant disease burden.

AIMS

This analysis aims to explore real-world treatment landscape of metastatic colorectal cancer in the third-line setting.

METHODS

We retrospectively analysed treatment of recurrent and advanced colorectal cancer (TRACC) registry database from 2009 onwards. Patients treated with palliative intent who progressed after two lines of therapies were included. One treatment line was defined as any combination of systemic therapy given until progression.

RESULTS

Out of 1820 patients treated palliatively, 32% (590 patients) met study criteria. Of these, 43% (254 patients) proceeded to third-line therapy, equating to 14% of all metastatic patients. In KRAS mutant or unknown tumours (97 patients), fluoropyrimidine (FP)-oxaliplatin combination was the most common choice (51%), followed by FP-irinotecan (15%), trifluridine/tipiracil (11%), mono-chemotherapy (10%), regorafenib (5%) and others (7%). Majority of FP-doublet (83%) was given as rechallenge. In 157 patients with KRAS wildtype disease, monotherapy with EGFR inhibitor was most commonly used (41%), followed by EGFR inhibitor with chemotherapy (20%), FP-doublet (18%), mono-chemotherapy (6%), trifluridine/tipiracil (6%), regorafenib (1%) and others (8%). Median overall survival was 7.1 months (range 0.4-41.2), and median time on third-line treatment was 3 months (range 0.1-40).

CONCLUSIONS

In real-world Australian population, treatment choices differed based on KRAS status and will likely change with the availability of newer drugs on the pharmaceutical benefits scheme. Survival outcomes are comparable to newer agents in clinical trials for select patients.

Phase II study of an oxaliplatin-based regimen for relapsed colon cancer patients treated with oxaliplatin-based adjuvant chemotherapy (INSPIRE study)

Background

The aim of this study was to evaluate the efficacy and safety of first-line chemotherapy with re-introduction of oxaliplatin (OX) more than 6 months after adjuvant chemotherapy including OX.

Methods

Stage II/III colon cancer patients with neuropathies of grade ≤ 1 who relapsed more than 6 months after adjuvant chemotherapy including OX were considered eligible. Eligible patients were treated with 5-fluorouracil, l-leucovorin and OX plus molecularly targeted agents or capecitabine and OX plus bevacizumab (BV) or S-1 and OX plus BV. The primary endpoint was the progression-free survival (PFS), and the secondary endpoints were the overall survival (OS), response rate (RR) and toxicity.

Results

A total of 50 patients were enrolled between September 2013 and May 2019. Twelve patients received 5-fluorouracil, l-leucovorin and OX (FOLFOX) plus BV, 21 patients received capecitabine and OX plus BV, 10 patients received S-1 and OX plus BV and 7 patients received FOLFOX plus cetuximab or panitumumab. The median PFS was 11.5 months (95% confidence interval [CI] 8.3–16.0), the median OS was 45.4 months (95% CI 37.4–NA), and the RR was 56.0% (95% CI 42.3–68.8). Adverse events of grade ≥ 3 that occurred in ≥ 5% of cases were neutropenia in 6 patients (12%), peripheral sensory neuropathy in 5 patients (10%), diarrhea in 4 patients (8%), hypertension in 4 patients (8%), anorexia in 3 patients (6%) and allergic reactions in 3 patients (6%).

Conclusions

First-line chemotherapy with re-introduction of OX more than 6 months after adjuvant chemotherapy including OX can be used safely with expected efficacy for relapsed colon cancer patients.

Oxaliplatin rechallenge in metastatic colorectal cancer patients with clinically significant oxaliplatin-induced peripheral neurotoxicity

We investigated whether rechallenge with oxaliplatin (OXA) can worsen the pre-existing oxaliplatin-induced peripheral neurotoxicity (OXAIPN) in metastatic colorectal cancer (mCRC) patients. Patients previously treated with OXA, having clinically significant grade 1 or 2 OXAIPN were assessed, after receiving rechallenge with OXA, using the clinical version of the Total Neuropathy Score (TNSc). Peripheral neuropathy was assessed at the end of first OXA exposure and at completion of OXA rechallenge. The first line OXA-based chemotherapy was completed at least 9 months earlier (OXA-free interval). We studied 25 mCRC patients, 14 males and 11 females, with a median age of 63 (35-77) years. After their first exposure to OXA-based chemotherapy, 9 (36%) patients developed grade 1 OXAIPN and 16 patients grade 2 (64%) neurotoxicity. OXA reintroduction with a median of 10 (8-14) cycles led to grade 1 OXAIPN in two patients (8%), grade 2 in 19 patients (76%), and grade 3 neuropathy in 4 (16%) patients Worsening of pre-existing OXAIPN was documented in seven (28%) patients and was significantly associated with higher OXA delivered cumulative dose (P < .001). Median TNSc scores following treatment (10; range 4-18) were significantly increased (P < .001), when compared to the scores recorded at the end of first line treatment (8; range 2-12). Rechallenging OXA appears to relatively worsen the severity of existing OXAIPN. However, the majority of rechallenged patients developed a clinically significant (grade 2) OXAIPN, rather than treatment-emergent grade 3. As such, OXA rechallenge might be a feasible option in patients previously having OXAIPN.

Chemotherapy rechallenge in metastatic colon cancer: A case report and literature review

BACKGROUND

Colorectal cancer (CRC) is the third leading cause of cancer-related death in males and females in the United States. Approximately, 20%-22% of patients have metastatic disease at the time of presentation, and 50%-60% will develop metastasis over the course of their disease. Despite advances in systemic therapies, there remains a paucity of effective third- and later-line therapies for patients with ongoing disease progression. However, rechallenging chemo-resistant CRC tumors with previously administered therapies is an emerging concept that may be a life-prolonging option for heavily treated metastatic colorectal cancer (mCRC).

CASE SUMMARY

A 41-year-old man with no previous medical history initially presented with worsening diffuse abdominal tenderness. Computed tomography was significant for a splenic flexure mass and hepatic lesions concerning for metastatic disease. He underwent a colectomy with anastomosis. Postoperative pathology was diagnostic for moderately to well-differentiated adenocarcinoma (T4bN1bM1a). He received adjuvant 5-fluorouracil, leucovorin, and oxaliplatin (FOLFOX), but therapy was discontinued due to the development of atrial fibrillation. Additional workup indicated a carcinoembryonic antigen level of 508.2 ng/mL, and mutational analysis found that the tumor was microsatellite instability-high and KRAS/BRAF wild-type. He was started on irinotecan with oxaliplatin (IROX), and bevacizumab (14 cycles), developed disease progression, was transitioned to FOLFOX and cetuximab, and then eventually three cycles of pembrolizumab. Following disease progression, he was rechallenged with IROX therapy, as he previously responded well to oxaliplatin-based therapy. The IROX rechallenge provided this patient with a ten-month survival benefit, decreased metastatic burden, and marked improvement in his clinical condition.

CONCLUSION

Rechallenge of previous lines of well-tolerated systemic chemotherapy regimens may be a valuable therapeutic strategy in patients with heavily-treated mCRC.

Previous Use of Anti-Vascular Endothelial Growth Factor Receptor Agents Decreases Efficacy of Fruquintinib in Metastatic Colorectal Cancer Refractory to Standard Therapies

Purpose

Fruquintinib is an anti-vascular endothelial growth factor receptor (VEGFR) agent. The FRESCO trial demonstrated that patients with metastatic colorectal cancer (mCRC) refractory to standard therapies could benefit from fruquintinib with tolerable adverse events (AEs). However, the efficacy and safety of fruquintinib in clinical practice has scarcely been reported, especially in patients with previous use of anti-VEGFR agents.

Methods

This retrospective study investigated the efficacy and safety of fruquintinib in patients with mCRC between January 2019 and December 2019. Progression-free survival (PFS) and overall survival (OS) were assessed by a Kaplan-Meier analysis and log-rank test. A Cox regression model was performed to identify independent prognostic factors.

Results

A total of 46 patients were included. The median PFS and OS were 3.1 months (95% confidence interval [CI], 1.9–4.3 months) and 9.0 months (95% CI, 7.2–10.8 months), respectively. Patients previously treated with anti-VEGFR agents had shorter median PFS compared with those without previous use of anti-VEGFR agents (1.9 vs. 3.7 months, P = 0.006), while the median OS was similar between the two groups (8.5 vs. 9.0 months, P = 0.992). Multivariate analysis revealed that the neutrophil-lymphocyte ratio (NLR) was an independent prognostic factor in PFS (hazard ratio [HR], 2.230; 95% CI, 1.191–4.517, P = 0.014) and OS (HR, 4.221; 95% CI, 1.683–10.586; P = 0.002). The most common non-hematological and hematological AEs were hand-foot syndrome (37.0%) and anemia (39.1%), respectively.

Conclusion

Fruquintinib was an effective third-line therapy in mCRC with tolerable AEs. Efficacy of fruquintinib was decreased in patients with previous use of anti-VEGFR agents. NLR was an independent prognostic factor in PFS and OS in patients treated with fruquintinib.

Oxaliplatin retreatment in metastatic colorectal cancer: Systematic review and future research opportunities

BACKGROUND

Oxaliplatin represents a main component of cytotoxic treatment regimens in colorectal cancer (CRC). Given its efficacy, oxaliplatin is frequently re-administered in the context of the continuum of care in metastatic CRC (mCRC). However, efficacy and tolerability of this therapeutic strategy has not been comprehensively assessed.

METHODS

We performed a systematic review of the literature on September 19th 2020, according to PRISMA criteria 2009. The research was performed on PubMed, ASCO Meeting Library, ESMO library and ClinicalTrials.gov for citations or ongoing trials.

RESULTS

64 records were retrieved and 13 included in the systematic review: 8 full-text articles, 4 abstracts and 1 ongoing clinical trial. According to readministration timing, studies were classified as rechallenge/reintroduction (n = 8) or stop & go/intermittent therapeutic strategies (n = 4). The studies presented wide heterogeneity in terms of efficacy (Response Rate 6-31%; Disease Control Rate 39-79%; median Progression-Free Survival 3.1-7 months). Those patients who received retreatment after prior adjuvant oxaliplatin or exploiting a stop-&-go strategy appeared to achieve better outcomes. However, no formal comparisons on treatment outcomes were feasible. The most frequent grade 3 or higher adverse events were hematologic toxicities (5-27%), peripheral neuropathy (5-14%) and hypersensitivity reactions (5-20%).

CONCLUSIONS

Retreatment with oxaliplatin for mCRC is practiced based on scarce and heterogeneous data indicating efficacy and manageable toxicity. The best strategy to exploit this approach remains to be defined, and the most promising research avenue to improve therapeutic index of oxaliplatin is represented by selection of responder patients whose tumors harbor molecular defects in the DNA damage repair pathway.

Refractory Metastatic Colorectal Cancer: Current Challenges and Future Prospects

Despite advances, patients with metastatic colorectal cancer (mCRC) still have poor long-term survival. Identification of molecular subtypes is important to guide therapy through standard treatment pathways and holds promise for the development of new treatments. Following standard first- and second-line chemotherapy plus targeted agents, many patients retain a reasonable performance status, and thus are seeking further effective treatment to extend life and maintain symptom control. The challenge lies in selecting the most appropriate therapy in the third- and fourth-line settings, from a range of options including the relatively new oral agents TAS-102 and regorafenib, or rechallenge with previous chemotherapy or anti-epidermal growth factor receptor (anti-EGFR) monoclonal antibodies (mAB). Beyond this, therapy consists of trials involving novel agents and new combinations of treatments with theoretical synergy and/or non-overlapping toxicity. There is a great focus on enhancing immunogenicity in mCRC, to reflect the impressive results of immunotherapy drugs in the small cohort with mismatch repair deficient (dMMR) mCRC. Rare molecular subtypes of mCRC are increasingly being identified, including Her2-positive disease, NTRK fusions and others. Clinical trials exploring the efficacy of immunomodulatory and precision agents are plentiful and will hopefully yield clinically meaningful results that can be rapidly translated into routine care.

Trifluridine/tipiracil: A practical guide to its use in the management of refractory metastatic colorectal cancer in Australia

Trifluridine/tipiracil is available on the Australian Pharmaceutical Benefits Scheme for the treatment of patients with metastatic colorectal cancer (mCRC) previously treated with, or not considered candidates for, fluoropyrimidine-, oxaliplatin- and irinotecan-based chemotherapies, anti-vascular endothelial growth factor agents and anti-epidermal growth factor receptor agents. This article reviews trifluridine/tipiracil clinical data and presents practical information on its use in the management of refractory mCRC in Australia. Whereas the primary mechanism of action of fluoropyrimidines such as fluorouracil (5-FU) and capecitabine is enzyme inhibition of nucleotide synthesis, trifluridine/tipiracil primarily acts by incorporation into DNA, resulting in DNA dysfunction. Trifluridine/tipiracil has activity in patients with 5-FU-resistant tumors and can be considered in patients with prior intolerance or toxicity to 5-FU. In the pivotal phase III RECOURSE trial evaluating trifluridine/tipiracil in chemotherapy-refractory mCRC, efficacy benefits were observed across all a priori prognostic subgroups including those defined by age (≥65 and ≥75 years), geographical origin, primary tumor site or KRAS status. Trifluridine/tipiracil therapy benefits appropriately selected patients who have an ECOG performance status of 0 or 1, with no more than mild hepatic impairment or mild-to-moderate renal impairment, and who are capable of adhering to oral therapy safely. Appropriate dosing, monitoring for adverse events and effective management of side effects are essential.

Evaluation of FOLFOX or CAPOX reintroduction with or without bevacizumab in relapsed colorectal cancer patients treated with oxaliplatin as adjuvant chemotherapy (REACT study)

BACKGROUND

Chemotherapy in relapsed colorectal cancer patients treated with oxaliplatin as adjuvant chemotherapy is under debate. REACT study aimed to investigate the efficacy of reintroducing modified FOLFOX6 (mFOLFOX6) or CAPOX with or without bevacizumab in recurrent colorectal cancer patients after oxaliplatin adjuvant chemotherapy.

METHODS

Patients that participated in this trial had a medical history of adjuvant chemotherapy, including oxaliplatin with a cumulative dose greater than 400 mg/m², and recurrence that was diagnosed more six months post adjuvant chemotherapy. Primary endpoints were response rate (RR) and disease control rate (DCR), while key secondary endpoints were time to treatment failure (TTF), progression-free survival (PFS), overall survival (OS), and safety.

RESULTS

A total of 31 patients were enrolled between October 2012 and October 2016. Of the 29 eligible patients, 7 received mFOLFOX6 and 22 received CAPOX. The RR was 62.1% (95% confidence interval 42.3-79.3) and the DCR was 82.8% (95% confidence interval 64.2-94.2). The RR for oxaliplatin-free interval was 100.0% in months 6-12 and 56.0% after 12 months. Median TTF, PFS, and OS were 6.3, 10.8, and 28.7 months, respectively. Grade 3 or worse peripheral sensory neuropathy developed in 6.5%. Allergic reactions occurred in 12.9% of the patients, with one (3.2%) grade 3 episode. There were no other severe treatment-related adverse events.

CONCLUSION

Reintroduction of oxaliplatin was feasible and achieved high RR or DCR in patients after more than 6 months post oxaliplatin adjuvant chemotherapy.

Current Options for Third-line and Beyond Treatment of Metastatic Colorectal Cancer. Spanish TTD Group Expert Opinion

Colorectal cancer (CRC) is a public health problem: it is the third most common cancer in men (746,000 new cases/year) and the second in women (614,000 new cases/year), representing the second leading cause of death by cancer worldwide. The survival of patients with metastatic CRC (mCRC) has increased prominently in recent years, reaching a median of 25 to 30 months. A growing number of patients with mCRC are candidates to receive a treatment in third line or beyond, although the optimal drug regimen and sequence are still unknown. In this situation of refractoriness, there are several alternatives: (1) To administer sequentially the 2 oral drugs approved in this indication: trifluridine/tipiracil and regorafenib, which have shown a statistically significant benefit in progression-free survival and overall survival with a different toxicity profile. (2) To administer cetuximab or panitumumab in treatment-naive patients with RAS wild type, which is increasingly rare because these drugs are usually indicated in first- or second-line. (3) To reuse drugs already administered that were discontinued owing to toxicity or progression (oxaliplatin, irinotecan, fluoropyrimidine, antiangiogenics, anti-epidermal growth factor receptor [if RAS wild-type]). High-quality evidence is limited, but this strategy is often used in routine clinical practice in the absence of alternative therapies especially in patients with good performance status. (4) To use specific treatments for very selected populations, such as trastuzumab/lapatinib in mCRC human epidermal growth factor receptor 2-positive, immunotherapy in microsatellite instability, intrahepatic therapies in limited disease or primarily located in the liver, although the main recommendation is to include patients in clinical trials.

Treatment of Rectal Cancer-Induced Disseminated Carcinomatosis of the Bone Marrow with FOLFOX plus Cetuximab and Panitumumab

Disseminated carcinomatosis of the bone marrow (DCBM) in colorectal cancer is an extremely rare complication with a poor prognosis. Here, we report a case of DCBM due to rectal cancer successfully treated with a combination of FOLFOX and an anti-epidermal growth factor receptor (EGFR) agent. The patient was a 38-year-old man diagnosed with rectal cancer with multiple bone and para-aortic lymph node metastases complicated by disseminated intravascular coagulation (DIC). He first recovered from DIC following cotreatment with FOLOX plus cetuximab; subsequently, the second attack was successfully treated with FOLFOX plus panitumumab. His initial condition was extremely poor, but he survived with two FOLFOX plus anti-EGFR regimens and died 333 days after introduction of chemotherapy.

A phase I study to determine the maximum tolerated dose of trifluridine/tipiracil and oxaliplatin in patients with refractory metastatic colorectal cancer: LUPIN study

Background The effectiveness of reintroducing oxaliplatin for metastatic colorectal cancer (mCRC) refractory to both oxaliplatin and irinotecan was previously reported in a phase II study (RE-OPEN). We conducted a phase I study to determine the maximum tolerated dose of oxaliplatin plus trifluridine/tipiracil (FTD/TPI) in patients with refractory mCRC. Patients and Methods Three dosages of intravenous oxaliplatin (50, 65 and 85 mg/m²) on days 1 and 15 and a fixed dose of FTD/TPI 35 mg/m² twice daily (bid) on days 1-5 and 15-19 every 4 weeks were investigated in patients with refractory mCRC using a 3 + 3 design. Eligible patients had received prior oxaliplatin-based treatment that achieved a response or stable disease followed by confirmed disease progression at least 6 months before entering the study. Results Twelve patients were enrolled in the study. Three of six patients in the oxaliplatin 85 mg/m² cohort had dose-limiting toxicities (DLTs) with treatment delays during the second cycle at ≥8 days due to grade ≥ 2 neutropenia or grade 2 AST/ALT increased. No DLTs were observed in the other cohorts. Grade ≥ 3 AEs were neutropenia (n = 3), thrombocytopenia (n = 1), anorexia (n = 1), and nausea (n = 1). There was no evidence of allergic reaction to oxaliplatin or severe peripheral sensory neuropathy. Conclusions A combination of FTD/TPI 35 mg/m² bid on days 1-5 and 15-19 and oxaliplatin 85 mg/m² on days 1 and 15 every 4 weeks could be a suitable regimen for the recommended dose of FTD/TPI plus oxaliplatin in patients with refractory mCRC.

Combination of Irinotecan, Oxaliplatin and 5-Fluorouracil as a Rechallenge Regimen for Heavily Pretreated Metastatic Colorectal Cancer Patients

PURPOSE

Our objective was to evaluate the benefit of re-exposing patients with refractory metastatic colorectal cancer (mCRC) to a combination of oxaliplatin, irinotecan and 5-fluorouracil treatment.

METHODS

We retrospectively analysed patients with mCRC who received a combination of oxaliplatin, irinotecan and fluorouracil as a rechallenge regimen after progressing on the same drugs. Both FOLFOXIRI and FOLFIRINOX were used. Toxicity was evaluated for each treatment cycle, and survival analysis was performed using the Kaplan-Meier method.

RESULTS

A total of 21 patients who were treated between January 2011 and December 2013 were selected for this study. Most of the patients (95.2%) had an ECOG status of 0-1. The median age at diagnosis was 52.1 years (range 36-77 years), and 14 (66.6%) patients had wild-type KRAS. Thirteen patients received FOLFIRINOX, and eight received FOLFOXIRI. Most patients had previously received at least three regimens, with 80% receiving anti-VEGF and 66% anti-EGFR antibodies. The response rate was 38%, and 24% patients had stable disease. The median time to disease progression was 4.0 months (range 1.0-9.1 months), and the median overall survival duration was 8.6 months (range 6.3-11.5 months). Most patients required dose adjustment and treatment delays. One patient experienced grade 5 neutropenic sepsis.

CONCLUSIONS

Both FOLFIRINOX and FOLFOXIRI are active and potentially feasible rechallenge treatment options for heavily pretreated patients with good performance status. With dose reduction and close monitoring for toxicity, the risk of serious adverse events can be minimised.

Regorafenib or rechallenge chemotherapy: which is more effective in the third-line treatment of metastatic colorectal cancer?

PURPOSE

To assess the efficacy and safety of regorafenib versus rechallenge chemotherapy in previously treated mCRC patients in third-line setting.

MATERIALS AND METHODS

The data of 104 patients diagnosed with mCRC enrolled from 2010 to 2017 in six oncology centers were analyzed. Tumor treatment options were obtained from follow-up and treatment files. Rechallenge chemotherapy was identified as the re-use of the regimen which was previously administered to patients in one of the therapy lines and obtained disease control, these were the patients whose disease did not progress within 3 months.

RESULTS

A total of 104 patients had received previously two lines of chemotherapy regimens for mCRC. Of these, 73 patients with mCRC who received regorafenib and 31 those who received rechallenge chemotherapy in third-line therapy were analyzed. Overall survival was better with rechallenge than it was with regorafenib (HR 0.29 95% CI 0.16-0.54, p < 0.001). Median OS was 12.0 months (95% CI 8.1-15.9) in rechallenge versus 6.6 months (95% CI 6.0-7.3) in regorafenib group (p < 0.001). Progression-free survival in the rechallenge group showed a higher median value of 9.16 months (95% CI 7.15-11.18) versus with that recorded in the regorafenib group of 3.41 months (95% CI 3.01-3.82), in favor of rechallenge chemotherapy. The most common adverse events of regorafenib was liver function test abnormality and hand-foot syndrome. Although grade 3 or 4 adverse events were similar, non-hematologic toxicities were more common than those of rechallenge.

CONCLUSIONS

Rechallenge is still a valuable option against regorafenib in patients who achieved disease control in one of the first two lines of therapy. Even though mCRC patients treated with regorafenib benefited clinically from this treatment, we revealed that chemotherapy rechallenge compared to regorafenib was more effective in the third-line treatment for mCRC patients.

Chemotherapy re-challenge response rate in metastatic colorectal cancer

Background

There are few treatment options in metastatic colorectal cancer (mCRC) after progression on standard chemotherapy. Third and fourth line therapies typically consist of regorafenib or trifluridine-tipiracil, however, clinical benefit of these medications is limited, as progression free survival is approximately 1.9 months for regorafenib (Grothey et al. 2013) and 2.0 months for trifluridine-tipiracil (Mayer et al. 2015). Another choice in this setting may include the re-initiation of previously used chemotherapy, therefore in this study we assessed the efficacy and tolerability of chemotherapy re-challenge.

Methods

This was a retrospective, cohort study assessing patients with mCRC who were 18-89 years of age and treated with re-challenge chemotherapy. Re-challenge chemotherapy was defined as re-initiation of oxaliplatin or irinotecan-based regimens at least nine months from the end of initial exposure. A minimum of four chemotherapy cycles was required to qualify as initial exposure. The key endpoints of this study were clinical benefit rate (CBR), defined as the proportion of patients with partial response or stable disease, and time to progression (TTP).

Results

A total of 67 chemotherapy re-challenges were accounted for in 51 patients. The overall CBR was 70.7%. Partial responses occurred in 50.7% cases. The TTP was 6.0 months. For the 51 cases of first re-challenge, the CBR was 75.5% and TTP was 6.5 months. Fourteen patients had a second re-challenge, and in these patients, the CBR was 61.5% and TTP was 4.1 months.

Conclusions

Oxaliplatin or irinotecan-based re-challenge should be considered as a third or fourth line treatment option in select patients with mCRC. CBR and especially TTP compare favorably to approved third line therapies such as regorafenib or trifluridine-tipiracil.

Rechallenge with oxaliplatin and peripheral neuropathy in colorectal cancer patients

BACKGROUND

Oxaliplatin (OXA) is a cornerstone in the treatment of colorectal cancer (CRC). Retreatment with OXA is frequently considered as salvage treatment. OXA-induced neuropathy (OIN) is the most frequent and feared long-term side effect.

PATIENTS AND METHODS

CRC patients receiving at least twice OXA-based chemotherapy lines at our institution between June 2000 and July 2016 were reviewed. The aim of this study was to investigate whether retreatment with OXA increases the risk of developing new or worsening previous neuropathy. OIN was assessed by National Cancer Institute-Common Toxicity Criteria for Adverse Events (NCI), Total Neuropathy Score© (TNS) and nerve-conduction studies.

RESULTS

106 patients were included in the analysis. Median age at OXA-based retreatment was 61.5 (20-83) years. After the first OXA-based chemotherapy treatment, 63.4% of patients developed OIN, 30.7 and 8.9% grades 2 and 3, respectively, after a median of 11 (1-17) cycles. After 30 (11-90) months of median to retreatment with a median of 8 (1-14) OXA cycles, 39.6, 22.6, and 0% of patients developed grade 1, 2, and 3 OIN, respectively. Worsening of the previous OIN was observed in one-third (31.1%) of all patients. OXA-cumulative dose was independently associated with greater risk of worsening OIN (p < 0.001). Non-significant trend towards higher TNSc© scores after retreatment was observed [5 (0-11) vs 6 (3-13), p = 0.083].

CONCLUSION

Retreatment with OXA in CRC patients is a feasible option even in patients who previously developed moderate or severe OIN. One-third of patients' OIN was worsened by retreatment. Neurological monitoring should be considered.

Rechallenge of oxaliplatin-containing regimens in the third- or later-line therapy for patients with heavily treated metastatic colorectal cancer

Purpose

The third- or later-line therapy available often yield poor survival benefit in patients metastatic colorectal cancer (mCRC). The retrospective study aimed to evaluate efficacy of rechallenge of oxaliplatin-containing regimens.

Patients and methods

Patients with mCRC who progressed from fluoropyrimidine, oxaliplatin, and irinotecan in the first- and second-line chemotherapy, were treated by reexposure to oxaliplatin-containing regimen. Patients treated by anti-epidermal growth factor receptor (EGFR) antibodies with irinotecan were included in the control arm.

Results

Ninety-five and 29 patients were treated with either oxaliplatin reexposure or anti-EGFR antibodies with irinotecan, respectively, as the third- or later-line therapy. The median time to treatment failure (TTF) and overall survival (OS) was 3.77 and 12.17 months in the oxaliplatin arm, with 4.77 months of TTF and 11.37 months of OS in the control arm; there was no significance between the 2 arms (p>0.05). Oxaliplatin reexposure resulted in 6.3% objective response rate with no complete response, 6 partial response, 39 stable disease, and 37 progressive disease. The disease control rate was 47.4% (45/95). The multivariate analysis found that patients who achieved disease control by oxaliplatin reexposure had a superior TTF (6.13 vs 1.7 months, p<0.001) and OS (15.73 vs 6.27 months, p<0.001) compared with those presenting with progressive disease.

Conclusion

This study showed that rechallenge of oxaliplatin-containing chemotherapy in the third- or later-line therapy may lead to tumor control and improved survival in mCRC patients, which was equivalent to that of anti-EGFR antibodies with irinotecan.

Clinical significance

Rechallenge of oxaliplatin-containing regimens in the third- or later-line of therapy is a common practice, despite few evidence available. The present study found that rechallenge of oxaliplatin-containing regimens produced equivalent tumor control and survival benefit to that of anti-EGFR antibodies with irinotecan in mCRC.

Oxaliplatin rechallenge in metastatic colorectal cancer patients after prior oxaliplatin treatment

Because the number of cytotoxic agents available for the treatment of metastatic colorectal cancer (mCRC) is limited, rechallenge with the same chemotherapy agents can provide a continuum of treatment. This study investigated the efficacy and feasibility of oxaliplatin rechallenge in mCRC patients who had been previously exposed to oxaliplatin-based chemotherapy. Patients were included if they had mCRC and evaluable disease, had remained disease-free or progression-free for at least 6 months after the last dose of prior oxaliplatin-based therapy, and were retreated with oxaliplatin therapy. Between January 2009 and May 2014, 110 patients were retreated with oxaliplatin-based regimens; of these, 42 (38.2%) had received prior oxaliplatin as adjuvant chemotherapy and 68 (61.8%) as palliative chemotherapy. The overall response rate to oxaliplatin rechallenge was 30.9% (34/110), and the disease control rate was 68.2% (75/110), with one patient achieving complete response, 33 achieving partial response, and 41 having stable disease. Median progression-free survival and overall survival following oxaliplatin rechallenge were 5.9 months (95% confidence interval [CI], 4.4-7.4 months) and 18.5 months (95% CI, 14.0-23.0 months), respectively. Sixteen patients experienced grade 2 or 3 neuropathy. Ten patients experienced any grade hypersensitivity reaction within four cycles of treatment, including six who stopped treatment due to grade 3 or 4 hypersensitivity reactions. Rechallenge with oxaliplatin-based therapy may be an option for patients who achieve at least 6 months of disease-free or progression-free survival with prior oxaliplatin-based chemotherapy. However, neurotoxicity and hypersensitivity reactions should be carefully monitored in this setting.

Beyond second-line therapy in patients with metastatic colorectal cancer: a systematic review

Background

The optimal chemotherapeutic regimen for use beyond the second line for patients with metastatic colorectal cancer (mCRC) remains unclear.

Materials and methods

We systematically searched the Cochrane Database of Systematic Reviews, EMBASE and Medline for records published between January 2002 and May 2017, and cancer congress databases for records published between January 2014 and June 2017. Eligible studies evaluated the efficacy, safety and patient-reported outcomes of monotherapies or combination therapies at any dose and number of treatment cycles for use beyond the second line in patients with mCRC. Studies were assessed for design and quality, and a qualitative data synthesis was conducted to understand the impact of treatment on overall survival and other relevant cancer-related outcomes.

Results

The search yielded 938 references of which 68 were included for qualitative synthesis. There was limited evidence to support rechallenge with chemotherapy, targeted therapy or both. Compared with placebo, an overall survival benefit for trifluridine/tipiracil (also known as TAS-102) or regorafenib has been shown for patients previously treated with conventional chemotherapy and targeted therapy. There was no evidence to suggest a difference in efficacy between these treatments. Patient choice and quality of life at this stage of treatment should also be considered when choosing an appropriate therapy.

Conclusions

These findings support the introduction of an approved agent such as trifluridine/tipiracil or regorafenib beyond the second line before any rechallenge in patients with mCRC who have failed second-line treatment.

Propensity Score Analysis of Regorafenib Versus Trifluridine/Tipiracil in Patients with Metastatic Colorectal Cancer Refractory to Standard Chemotherapy (REGOTAS): A Japanese Society for Cancer of the Colon and Rectum Multicenter Observational Study

BACKGROUND

This study compared the efficacy of regorafenib and trifluridine/tipiracil (TFTD) in patients with metastatic colorectal cancer (mCRC) who are refractory to standard chemotherapy, because despite their clinical approval, it still remains unclear which of these two drugs should be used as initial treatment.

MATERIALS AND METHODS

The clinical data of patients with mCRC who were treated with regorafenib or TFTD and those of drug-naive patients, between June 2014 and September 2015, were retrospectively collected from 24 institutions in Japan. Overall survival (OS) was evaluated using the Cox's proportional hazard models based on propensity score adjustment for baseline characteristics.

RESULTS

A total of 550 patients (223 patients in the regorafenib group and 327 patients in the TFTD group) met all criteria. The median OS was 7.9 months (95% confidence interval [CI], 6.8-9.2) in the regorafenib group and 7.4 months (95% CI, 6.6-8.3) in the TFTD group. The propensity score adjusted analysis showed that OS was similar between the two groups (adjusted hazard ratio [HR], 0.96; 95% CI, 0.78-1.18). In the subgroup analysis, a significant interaction with age was observed. Regorafenib showed favorable survival in patients aged <65 years (HR, 1.29; 95% CI, 0.98-1.69), whereas TFTD was favored in patients aged ≥65 years (HR, 0.78; 95% CI, 0.59-1.03).

CONCLUSION

No significant difference in OS between regorafenib and TFTD was observed in patients with mCRC. Although the choice of the drug by age might affect survival, a clearly predictive biomarker to distinguish the two drugs should be identified in further studies.

IMPLICATIONS FOR PRACTICE

Previous studies of patients with metastatic colorectal cancer refractory to standard chemotherapy had demonstrated that both regorafenib and trifluridine/tipiracil could result in increased overall survival compared with placebo, but there are no head-to-head trials. This large, multicenter, observational study retrospectively compared the efficacy of regorafenib and trifluridine/tipiracil in 550 patients with metastatic colorectal cancer refractory to standard chemotherapy who had access to both drugs. Although no difference in overall survival was found between the two drugs in adjusted analysis using propensity score, regorafenib showed favorable survival in patients aged <65 years, whereas trifluridine/tipiracil was favored in patients aged ≥65 years in the subgroup analysis.

REOX: Evaluation of the Efficacy of Retreatment With an Oxaliplatin-containing Regimen in Metastatic Colorectal Cancer: A Retrospective Single-center Study

BACKGROUND

Treatment of metastatic colorectal adenocarcinoma (mCRC) has evolved, and survival is over 30 months in contemporary trials. Nevertheless, there is a paucity of effective regimes after the first or second-line treatment. Thus, reexposure to previously used drugs has become a treatment strategy for some patients. We aimed to evaluate the efficacy of retreatment with an oxaliplatin-containing regimen in mCRC and correlate this with clinicopathologic features.

PATIENTS AND METHODS

We retrospectively analyzed 83 patients with mCRC who underwent reexposure to oxaliplatin (REOX). REOX was defined as a second trial of an oxaliplatin-containing regimen after a previous failure. Primary endpoint was time to treatment failure (TTF).

RESULTS

The median age was 53.5 years, and the female/male ratio was 51.8%/48.2%. The site of the primary tumor was colon (67.5%) and rectal (32.5%). KRAS was mutated in 39.8%. Liver-limited metastasis was found in 19.3% of patients. The main regimen was 5-fluorouracil, levoleucovorin, and oxaliplatin (mFOLFOX6) (84.3%). Bevacizumab and cetuximab were used in 42.2% and 6% of patients, respectively. REOX was used in the third and fourth lines in 48.2% and 25.3% of patients, respectively. The median TTF after REOX was 6.04 months. Overall survival (OS) was 10.04 months. Disease control (complete response + partial response + stable disease) was observed in 56.6%, whereas 42.2% had progressive disease. Partial response + complete response to previous oxaliplatin was predictive of prolonged OS. Patients who attained disease control had better median OS compared with those with progressive disease (14.5 vs. 6.24 months; P < .0001).

CONCLUSION

In the setting of heavily pretreated patients with mCRC, REOX was an effective treatment, with mTTF of 6.04 months in our cohort. Selection of patients with the longest time since previous oxaliplatin can translate in better outcome. Further studies should be conducted to confirm our data.

Dual Inhibition of EGFR and c-Src by Cetuximab and Dasatinib Combined with FOLFOX Chemotherapy in Patients with Metastatic Colorectal Cancer

Purpose: Aberrant activation of the intracellular tyrosine kinase Src has been implicated as a mechanism of acquired chemotherapy resistance in metastatic colorectal cancer (mCRC). Here, the oral tyrosine kinase Src inhibitor, dasatinib, was investigated in combination with FOLFOX and cetuximab.Experimental Design: We performed a phase IB/II study of 77 patients with previously treated mCRC. Primary objectives were to determine the maximum tolerated dose, dose-limiting toxicities (DLT), pharmacodynamics, and efficacy. Using a 3 + 3 design, patients received FOLFOX6 with cetuximab and escalating doses of dasatinib (100, 150, 200 mg daily), followed by a 12-patient expansion cohort at 150 mg. Phase II studies evaluated FOLFOX plus dasatinib 100 mg in KRAS c12/13^mut patients or in combination with cetuximab if KRAS c12/13^WT FAK and paxillin were utilized as surrogate blood biomarkers of Src inhibition, and paired biopsies of liver metastases were obtained in patients in the expansion cohort.Results: In phase IB, the DLTs were grade 3/4 fatigue (20%) and neutropenia (23%). In phase II, grade 3/4 fatigue (23%) and pleural effusions (11%) were present. Response rates were 20% (6 of 30) in the phase IB escalation and expansion cohort and 13% (3 of 24) and 0% (0 of 23) in the KRAS c12/13^WT and mutant cohorts of phase II, respectively. Median progression-free survival was 4.6, 2.3, and 2.3 months, respectively. There was no evidence of Src inhibition based on surrogate blood biomarkers or paired tumor biopsies.Conclusions: The combination of dasatinib plus FOLFOX with or without cetuximab showed only modest clinical activity in refractory colorectal cancer. This appears to be primarily due to a failure to fully inhibit Src at the achievable doses of dasatinib. The combination of dasatinib plus FOLFOX with or without cetuximab did not show meaningful clinical activity in refractory colorectal cancer due to failure to fully inhibit Src. Clin Cancer Res; 23(15); 4146-54. ©2017 AACR.

Onivyde for the therapy of multiple solid tumors

Drug delivery system based on nanobiotechnology can improve the pharmacokinetics and therapeutic index of chemotherapeutic agents, which has revolutionized tumor therapy. Onivyde, also known as MM-398 or PEP02, is a nanoliposomal formulation of irinotecan which has demonstrated encouraging anticancer activity across a broad range of malignancies, including pancreatic cancer, esophago-gastric cancer, and colorectal cancer. This up-to-date review not only focuses on the structure, pharmacokinetics, and pharmacogenetics of Onivyde but also summarizes clinical trials and recommends Onivyde for patients with advanced solid tumors.

Advances and Challenges of Liposome Assisted Drug Delivery

The application of liposomes to assist drug delivery has already had a major impact on many biomedical areas. They have been shown to be beneficial for stabilizing therapeutic compounds, overcoming obstacles to cellular and tissue uptake, and improving biodistribution of compounds to target sites in vivo. This enables effective delivery of encapsulated compounds to target sites while minimizing systemic toxicity. Liposomes present as an attractive delivery system due to their flexible physicochemical and biophysical properties, which allow easy manipulation to address different delivery considerations. Despite considerable research in the last 50 years and the plethora of positive results in preclinical studies, the clinical translation of liposome assisted drug delivery platforms has progressed incrementally. In this review, we will discuss the advances in liposome assisted drug delivery, biological challenges that still remain, and current clinical and experimental use of liposomes for biomedical applications. The translational obstacles of liposomal technology will also be presented.