Bevacizumab Combined with S-1 and Raltitrexed for Patients with Metastatic Colorectal Cancer Refractory to Standard Therapies: A Phase II Study

Lessons Learned

• Bevacizumab combined with S-1 and raltitrexed demonstrated positive antitumor efficacy and acceptable toxicity.
• This combination might represent a treatment option for refractory metastatic colorectal cancer.

     

A Phase I Clinical Trial of Trametinib in Combination with TAS-102 in Patients with Chemotherapy-Resistant RAS-Mutated (PIK3CA/PTEN-Wild Type) Metastatic Colorectal Cancer

PurposeWe conducted a phase I study to evaluate the maximum tolerated dose (MTD), safety, and efficacy of trametinib in combination with TAS-102 in patients with chemotherapy-refractory KRAS-mutant, wild-type PIK3CA/PTEN metastatic colorectal cancer (mCRC).MethodsA 3+3 dose de-escalation single arm phase I clinical trial was performed in patients with chemorefractory mCRC without priorTAS-102 exposure. Patients received fixed dosing of trametinib 2mg oral daily along with de-escalating doses of TAS-102 beginning at 35 mg/m² twice daily on days 1-5 and days 8-12 every 28 days. Primary endpoint was evaluation of MTD.Results25 eligible patients were enrolled in this study. During the dose de-escalation phase, no dose-limiting toxicities (DLT) were observed at the full doses of trametinib/TAS-102 and the MTD was determined to be TAS-102 35 mg/m² orally twice daily on days 1 to5 and days 8 to12 every 28 days with continuous trametinib dosing at 2mg orally daily. No patients achieved a partial or complete response. 5 of 21 evaluable patients (23.81%) achieved a stable disease response. Median PFS was two months (95% confidence interval [CI] 1.70-4.82) while median OS was 7 months (95% CI 6.36-11.48). Treatments were well tolerated with most common grade ≥ 3 adverse events being anemia (20%), neutropenia (12%), leukopenia (8%), diarrhea (8%), rash (4%), and fatigue (4%).ConclusionsTrametinib in combination with TAS-102 demonstrated a manageable safety profile. However, this combination did not achieve meaningful clinical benefit in patients with RAS-mutated PIK3CA and PTEN wild-type refractory mCRC. Clinical trial information: NCT03317119.     

Cost-effectiveness Analysis of Regorafenib and TAS-102 in Refractory Metastatic Colorectal Cancer in the United States

Background

Regorafenib and TAS-102 are standard treatment options in refractory metastatic colorectal cancer based on improvement in overall survival by 6 and 8 weeks, respectively, when compared with best supportive care alone (BSC). Given the small incremental clinical benefit, we evaluated their cost-effectiveness from a United States payer’s perspective.

Randomized Phase II Open-Label Study of mFOLFOX6 in Combination With Linifanib or Bevacizumab for Metastatic Colorectal Cancer

BackgroundAlthough CRC is the third most commonly diagnosed cancer in the United States, second-line CRC treatment is limited. In this trial we examined the efficacy and safety of linifanib, an oral, potent, selective tyrosine kinase inhibitor of vascular endothelial growth factor and platelet-derived growth factor receptor families, with mFOLFOX6, compared with bevacizumab and mFOLFOX6, in previously treated metastatic CRC.Patients and MethodsOne hundred forty-eight patients with advanced CRC previously treated with fluoropyrimidine or irinotecan received bevacizumab (10 mg/kg, intravenous), low-dose linifanib (7.5 mg), or high-dose linifanib (12.5 mg), with mFOLFOX6. The primary end point was progression-free survival (PFS). Secondary objectives included overall survival (OS), objective response rate (ORR), and safety.ResultsNo statistically significant differences in PFS occurred between bevacizumab and linifanib doses (low, hazard ratio [HR], 1.453 [95% confidence interval [CI], 0.830-2.539]; high, HR, 1.257 [95% CI, 0.672-2.351]). Median OS values were similar for bevacizumab and high-dose linifanib (bevacizumab, 16.5 months [95% CI, 13.0-not available]; high-dose linifanib, 16.4 months [95% CI, 11.9-21.7]; low-dose linifanib, 12.0 months [95% CI, 10.1-13.0]). ORRs were similar (bevacizumab, 34.7% [95% CI, 21.7-49.6]; low-dose linifanib, 24.0% [95% CI, 13.1-38.2]; high-dose linifanib, 22.4% [95% CI, 11.8-36.6]). Median cycles of 5-fluorouracil were reduced in the linifanib arms, versus the bevacizumab arm. Grade 3/4 adverse event occurrences were more frequent with linifanib. Palmar-plantar erythrodysesthesia, hypothyroidism, and thrombocytopenia were more common with high-dose linifanib than bevacizumab.ConclusionCombining linifanib with mFOLFOX6 as a second-line treatment for metastatic CRC did not improve PFS, radiographic findings, or duration of response versus bevacizumab and mFOLFOX6.     

A Phase I/II Study of XELIRI Plus Bevacizumab as Second‐Line Chemotherapy for Japanese Patients With Metastatic Colorectal Cancer (BIX Study)

Background.

Capecitabine is used mainly with oxaliplatin to treat metastatic colorectal cancer (mCRC). Results from capecitabine plus irinotecan (XELIRI) with or without bevacizumab (BV) have been reported in Europe but not in Japan. Consequently, the safety and efficacy of XELIRI plus BV in Japanese patients with mCRC were assessed in a single-arm phase II study.

Methods.

Eligible patients had had prior chemotherapy containing BV for mCRC and wild-type or heterozygous UGT1A1. Therapy in each 21-day treatment cycle consisted of capecitabine (800 mg/m² twice daily on days 1–15), irinotecan (200 mg/m² on day 1), and BV (7.5 mg/kg on day 1). The primary endpoint was dose-limiting toxicity in phase I and progression-free survival (PFS) in phase II.

Results.

A total of 34 patients (6 in phase I, 28 in phase II) were enrolled from May 2010 to June 2011. Baseline characteristics included a median age of 60 years (range: 22–74 years) for 24 men and 10 women. No dose-limiting toxicities appeared in phase I. Median PFS was 240 days (95% confidence interval: 179–311 days). Overall response rate was 18.1%, and the disease-control rate was 90.9%. The incidence of adverse events frequently associated with irinotecan and capecitabine were neutropenia (any grade, 55.9%; grade 3 or 4, 11.8%), diarrhea (any grade, 50%; grade 3 or 4, 5.9%), and hand-foot syndrome (any grade, 61.8%; grade 3 or 4, 5.9%).

Conclusion.

Our results suggest that XELIRI plus BV is well tolerated and effective as a second-line treatment for mCRC in Japanese patients. This regimen could be especially appropriate for patients resistant to oxaliplatin-based regimens.     

Phase II Study of Olaparib (AZD‐2281) After Standard Systemic Therapies for Disseminated Colorectal Cancer

Background.

Effective new agents for patients with colorectal cancer (CRC) with disease progression during standard therapy regimens are needed. We hypothesized that poly ADP ribose polymerase (PARP) inhibitor therapy in patients with CRC and inefficient tumor DNA repair mechanisms, such as those with high-level microsatellite instability (MSI-H), would result in synthetic lethality.

Methods.

This was an open-label phase II trial testing olaparib 400 mg p.o. b.i.d. for patients with disseminated, measurable CRC failing standard therapies with centrally confirmed tumor MSI status. The primary endpoint was the tumor response, assessed by RECIST, version 1.0. The secondary endpoints were safety/toxicity, progression-free survival (PFS), and overall survival (OS).

Results.

Thirty-three patients (20 microsatellite stable [MSS], 13 MSI-H) were enrolled. The median age for all patients was 57 years and for MSS and MSI-H patients was 51 and 61 years, respectively. All patients received at least one 28-day cycle of olaparib. No patient had a complete or partial response. Nausea (48%), fatigue (36%), and vomiting (33%) were the most commonly reported treatment-related adverse events. The median PFS for all patients was 1.84 months. No statistically significant differences were found in the median PFS or OS for the MSS group compared with the MSI-H group.

Conclusion.

Single-agent olaparib delivered after failure of standard systemic therapy did not demonstrate activity for CRC patients, regardless of microsatellite status. Future trials, testing PARP inhibitors in patients with CRC should focus on the use of DNA-damaging chemotherapy and/or radiation therapy, combined with PARP inhibitors, remembering the toxicity reported in the present study.

Implications for Practice:

Microsatellite instability (MSI-H) colorectal tumors exhibit hypermethylation in tumor mismatch repair genes, or have mutations in one or more of these genes resulting from a germ-line defect (Lynch syndrome). PARP inhibitors such as olaparib are most effective in tumors associated with inability to repair DNA damage. However, in this trial, single agent olaparib failed to elicit responses in patients with MSI-H colorectal tumors, and in those with microsatellite-stable tumors. It is possible that by adding olaparib to radiation therapy, or to a systemic DNA damaging agent, tumor lethality could be obtained. However, the price would be increased toxicity.     

A Phase 1B Study of Dulanermin in Combination With Modified FOLFOX6 Plus Bevacizumab in Patients With Metastatic Colorectal Cancer

ObjectivesThe study objectives were to evaluate the safety, tolerability, and preliminary efficacy of multiple doses of dulanermin in combination with modified FOLFOX6 and bevacizumab in previously untreated patients with locally advanced, recurrent, or metastatic colorectal cancer.Patients and MethodsA total of 23 patients received dulanermin at dosages of 4.5 or 9 mg/kg/d given on days 1 to 3 of each 14-day cycle along with standard dosing of modified FOLFOX6 plus bevacizumab. Dose-limiting toxicities, adverse events (AEs), maximum tolerated dose, and response according to Response Evaluation Criteria in Solid Tumors were assessed.ResultsIn the first cohort (3 patients given dulanermin at 4.5 mg/kg/d) and second cohort (6 patients given dulanermin at 9 mg/kg/day), no dose-limiting toxicities were observed. The subsequent 14 patients were treated with a dulanermin dosage of 9 mg/kg/d. Patients (N = 23) received 2 to 42 cycles of dulanermin (median 15). The most common grade 3 or 4 AEs were neutropenia (39%), hypertension (17%), peripheral neuropathy (17%), hand-foot syndrome (13%), and pulmonary embolism (13%). Three patients (13%) discontinued the study because of serious AEs. Overall, a best response of partial response was observed in 13 patients (57%) (9 confirmed, 4 unconfirmed), stable disease was observed in 7 patients (30%), and disease progression was observed in 3 patients (13%). The median progression-free survival was 9.9 months (95% confidence interval, 7.0-12.7).ConclusionsOverall, the addition of dulanermin to first-line FOLFOX plus bevacizumab was well tolerated in patients with advanced colorectal cancer, with similar AEs that would be expected from FOLFOX plus bevacizumab. A randomized study is required to assess the clinical efficacy of dulanermin in this patient population.     

Value-Based Analysis of Therapies in Refractory Metastatic Colorectal Cancer in US

BackgroundRecent phase 2 trials have provided data supporting regorafenib dose optimization (ReDO) and trifluridine/tipiracil (TAS-102) with bevacizumab (TAS-BEV) as treatment options in refractory metastatic colorectal cancer (mCRC). Historically, regorafenib standard dose (RSD) and TAS-102 have been utilized as third-line options in mCRC. Given the incorporation of ReDO and TAS-BEV as treatment options, we sought to evaluate relative cost-effectiveness of ReDO vs. RSD, TAS-102, and TAS-BEV for mCRC from a payer perspective.MethodsA Markov model was constructed to estimate total costs and quality-adjusted life-years (QALYs) for ReDO, RSD, TAS-102, and TAS-BEV. Clinical parameters were obtained from phase 2 and 3 trials for comparators. Health state utility values were from the RSD phase 3 clinical trial. Incremental cost-effectiveness ratios (ICERs) were utilized to compare treatments. Model robustness was checked with one-way and probabilistic sensitivity analyses.ResultsIn the base case, ReDO was dominant over TAS-BEV (ie provided a higher QALY at a lower cost). ReDO produced an ICER of $104,308 per QALY relative to RSD and $37,966 relative to TAS-102. In one-way sensitivity analyses, monthly drug cost of TAS-BEV was the most influential parameter determining relative cost-effectiveness between TAS-BEV and ReDO. When TAS-102 and RSD were independently compared to ReDO, the most influential parameters were related to duration of OS and PFS and costs of managing AEs.ConclusionsThe optimum dosing strategy for regorafenib has improved its benefit-to-toxicity ratio and relative cost-effectiveness compared to RSD, TAS-102, and TAS-BEV.     

Economic Evaluation of Adding Bevacizumab to Chemotherapy for Metastatic Colorectal Cancer (mCRC) Patients in Indonesia

Objective: Since 2016, bevacizumab has been widely used to treat metastatic colorectal cancer (mCRC) in Indonesia. Nevertheless, the high cost of bevacizumab has raised the question of whether the therapy is considered cost-effective and should be included in the national health insurance system. This study aimed to assess the cost-effectiveness of bevacizumab plus chemotherapy versus chemotherapy alone for the treatment of mCRC patients. Methods: A Markov model was applied using the perspective of the Indonesian healthcare system to assess cost-effectiveness. The health outcomes were expressed in terms of quality-adjusted life years (QALY) using the validated EuroQoL-5D-5L instrument. Data for medical costs were collected from hospital billings in four hospitals located in three different cities in Indonesia. Meanwhile, data for utility were obtained from interviewing 90 patients who came to the hospital. We compared those mCRC patients who received chemotherapy alone either with FOLFOX or FOLFIRI, versus patients who received the addition of bevacizumab. Results: With the perspective of societal, the incremental cost-effectiveness ratio (ICER) of adding bevacizumab was USD 49,312 per QALY gained using secondary data and USD 28,446 per QALY using real world data. Conclusion: Using either a healthcare or societal perspective, the addition of bevacizumab for mCRC treatment was considered not cost-effective.     

Regorafenib Is Associated With Increased Skeletal Muscle Loss Compared to TAS-102 in Metastatic Colorectal Cancer

BackgroundCurrent guidelines of the National Comprehensive Cancer Network and the European Society of Medical Oncology recommend regorafenib or trifluridine/tipiracil (TAS-102) for third-line therapy of metastatic colorectal cancer (mCRC). We evaluated the impact of regorafenib and TAS-102 treatment on skeletal muscle dynamics and sarcopenia.Patients and MethodsThis retrospective analysis was based on unselected, consecutive mCRC patients treated with regorafenib and/or TAS-102 during third or later line of therapy at our tertiary-care cancer center in Salzburg, Austria. The skeletal muscle index (SMI, cm²/m²) and sarcopenia were evaluated from cross-sectional computed tomographic images at the level of the third lumbar vertebra.ResultsBetween January 2013 and April 2018, a total of 45 patients had received regorafenib and/or TAS-102. At initial mCRC diagnosis and at initiation of third-line therapy, 24% and 54% of patients presented with sarcopenia. A statistically significant skeletal muscle loss was observed during regorafenib treatment (median SMI change: −2.75 cm²/m² [−6.3%]; P < .0001), which was not the case during TAS-102 therapy (−1.5 cm²/m² [−3.5%]; P = .575). Furthermore, subclassification of patients into 3 groups—normal muscle mass, stable sarcopenia, and new-onset sarcopenia—at initiation of third-line therapy permitted discrimination of overall survival, with 1-year overall survival rates of 61%, 29%, and 16%, respectively (P = .04).ConclusionThe frequency of sarcopenia increases during the course of mCRC and negatively affects survival. In contrast to TAS-102, regorafenib is associated with increased skeletal muscle loss during mCRC treatment and should therefore be used with caution in mCRC patients with preexisting sarcopenia or a history of recent weight loss.     

A Multicenter Clinical Phase II Study of FOLFOXIRI Plus Bevacizumab as First-line Therapy in Patients With Metastatic Colorectal Cancer: QUATTRO Study

Background

FOLFOXIRI (Fluorouracil, folinate, oxaliplatin, and irinotecan) plus bevacizumab improved progression-free survival (PFS) and overall survival in patients with metastatic colorectal cancer (mCRC), compared with FOLFIRI (fluorouracil, folinate, and irinotecan) plus bevacizumab, but significantly increased the incidences of adverse events. The efficacy and safety profiles of FOLFOXIRI plus bevacizumab in ethnic Asian patients have not been established yet.

Efficacy and Safety of Bevacizumab in Chinese Patients with Metastatic Colorectal Cancer

Objective: To evaluate the efficacy and safety of bevacizumab in the treatment of patients with metastatic colorectal cancer (mCRC). Methods: In a single-center, observational study of 91 Chinese patients with mCRC who received bevacizumab in combination with chemotherapy was conducted. Objective response rates (ORRs), progression-free survival (PFS), overall survival (OS) and adverse events were recorded, and the relationships between various clinical factors and PFS or OS were evaluated by Cox proportional hazards models. Results: Treatment with bevacizumab and chemotherapy was effective and tolerable. Univariate analysis showed that PFS and OS were significantly associated with the Eastern Cooperative Oncology Group performance status (ECOGPS) score, duration of bevacizumab exposure, and whether chemotherapy was continued after discontinuation of bevacizumab treatment. A multivariate analysis showed that the duration of bevacizumab exposure and whetherchemotherapy was continued after discontinuation of bevacizumab were independent prognostic factors for PFS and OS. Conclusion: In Chinese mCRC population, the shorter the duration of exposure to bevacizumab and chemotherapy, the worse the prognosis is.