Comparison of Standard Initial Dose and Reduced Initial Dose Regorafenib for Colorectal Cancer Patients: A Retrospective Cohort Study

Cumulative Dose of Regorafenib in Patients With Metastatic Colorectal Cancer: A Multicenter Cohort Study

PURPOSE

This study aimed to evaluate the prognostic effect of the cumulative dose (CD) of regorafenib on survival in patients with metastatic colorectal cancer (mCRC).

MATERIALS AND METHODS

This retrospective study utilized the Taipei Medical University Clinical Research Database for analysis. Patients aged ≥ 20 years with mCRC who were prescribed regorafenib between January 2014 and December 2021 were identified and then divided into low- and high-CD groups (≤ 4200 mg vs. > 4200 mg). Overall survival (OS), time-to-treatment discontinuation (TTD), and the incidence of five common adverse events were compared between groups. In addition, natural cubic splines were employed to examine the non-linear relationship between cumulative doses and survival in the multivariate Cox regression model.

RESULTS

A total of 259 patients were enrolled, with 130 in the low-CD group and 129 in the high-CD group; the median OS was 4.6 months and 9.8 months, respectively (p < 0.01). The median TTD was 51.5 days for the low-CD group and 72.0 days for the high-CD group (p < 0.01). No significant difference in drug-related adverse events was observed between groups. In the multivariate Cox analysis, a CD ≤ 4200 mg was a negative prognostic factor (hazard ratio 1.41 [95% confidence interval 1.08-1.84], p = 0.01). In addition, patients on a dose range between 4368 and 5376 mg exhibited minimal mortality risk.

CONCLUSION

The cumulative doses of regorafenib > 4200 mg were associated with improved survival. The suggested optimal dose range serves as a reference for dose modification in clinical practice.

"Start low, go slow," a strategy to tailor treatment dosing in older or vulnerable adults with advanced solid cancer: A systematic review and meta-analysis

INTRODUCTION

The use of standard-dose cancer treatment can result in a decline in the functional abilities of older adults with cancer. The "start-low, go-slow" (SLGS) strategy involves initiating cancer treatment at lower-than-standard doses in selected patients who are vulnerable to excess toxicity and escalating based on tolerance. We performed a systematic review and meta-analysis to assess the available data and the effectiveness of the SLGS strategy in the treatment of cancer in older adults with incurable solid cancer.

MATERIALS AND METHODS

The review was registered with PROSPERO. Two independent reviewers (GA and TP) conducted a comprehensive search across multiple databases (PubMed/Medline, Journal of Geriatric Oncology, American Society of Clinical Oncology abstracts, and EMBASE) of prospective studies involving patients with solid tumors who received SLGS. SLGS was defined as starting cancer therapy with a lower than standard dose and dose-escalating, if possible. The main objective of this study was to evaluate overall survival (OS) in patients treated with the SLGS strategy. Secondary objectives were to analyze treatment discontinuation and toxicity in patients treated with the SLGS strategy. Additionally, we aimed to compile a comprehensive report on studies employing the SLGS strategy in solid oncology. We utilized a random-effects meta-analysis model to consider the diversity among patient populations with different cancer stages, types, and treatments. Two researchers independently employed the Newcastle-Ottawa Quality (NOQ) assessment for cohort analysis to evaluate the methodological quality and standard of outcomes reporting in the included studies. The quality of evidence was appraised using the Grading recommendations assessment, development and evaluation GRADE summary of findings tool.

RESULTS

The systematic search identified a total of 12,690 articles. Thirteen studies met criteria for inclusion in the systematic review, totaling 8546 patients. Twelve studies evaluated OS. However, only five studies focused solely on older adults, and the studies involved different types of cancer without following a specific pattern. In meta-analysis of survival among three studies, patients who underwent the SLGS approach had lower mortality (hazar ratio 0.91, 95 % confidence interval [CI] 0.85-0.98, p = 0.01, i2 = 0 %). Toxicity ranged from 5 % to 89 % across studies; SLGS had lower grade 3 and 4 toxicity compared to the standard dose (six studies, meta-analysis relative risk 0.86, 95 % CI 0.75-0.98, p < 0.02, i2 = 30 %). Treatment discontinuation was not different for SLGS vs. standard dose (seven studies, meta-analysis RR 0.96, 95 % CI 0.87-1.05, p = 0.37 i2 = 50 %).

DISCUSSION

This systematic review and meta-analysis suggests that a SLGS approach to systemic therapy dosing may reduce toxicity without affecting survival among older patients with solid tumors, although results are limited by a limited number of prospective studies. Additional research is needed to understand better the effects of SLGS in older adults receiving palliative chemotherapy.

Real-world dosing of regorafenib and outcomes among patients with metastatic colorectal cancer: a retrospective analysis using US claims data

BACKGROUND

The randomized, dose-optimization, open-label ReDOS study in US patients with metastatic colorectal cancer (CRC) showed that, compared with a standard dosing approach, initiating regorafenib at 80 mg/day and escalating to 160 mg/day depending on tolerability increased the proportion of patients reaching their third treatment cycle and reduced the incidence of adverse events without compromising efficacy. Subsequently, the ReDOS dose-escalation strategy was included as an alternative regorafenib dosing option in the National Comprehensive Cancer Network (NCCN) Clinical Practice Guidelines. A retrospective analysis was conducted using a US claims database to assess whether inclusion of this dose-escalation strategy in NCCN Guidelines has influenced the use of flexible dosing in routine US clinical practice, and to describe clinical outcomes pre- and post-inclusion in NCCN Guidelines.

METHODS

Patients with CRC in the Optum's de-identified Clinformatics® Data Mart database initiating regorafenib for the first time between January 2016 and June 2020 were stratified based on whether they initiated regorafenib pre- or post-inclusion of ReDOS in NCCN Guidelines, and in two groups: flexible dosing (< 160 mg/day; < 84 tablets in the first treatment cycle) and standard dosing (160 mg/day; ≥ 84 tablets in the first treatment cycle). The primary endpoints were the proportion of patients who initiated their third treatment cycle and the mean number of treatment cycles per group.

RESULTS

703 patients initiated regorafenib during the study period, of whom 310 (44%) initiated before and 393 (56%) initiated after inclusion of ReDOS in NCCN Guidelines. After inclusion in the guidelines, the proportion of patients who received flexible dosing increased from 21% (n = 66/310) to 45% (n = 178/393), the proportion who received standard dosing decreased from 79% (n = 244/310) to 55% (n = 215/393), the proportion who initiated their third treatment cycle increased from 36% (n = 113/310) to 46% (n = 179/393), and the mean (standard deviation) number of treatment cycles increased from 2.6 (2.9) to 3.2 (3.1).

CONCLUSIONS

Following inclusion of ReDOS in NCCN Guidelines, real-world data suggest that US clinicians have markedly increased use of flexible dosing in clinical practice, potentially maximizing clinical benefits and safety outcomes for patients with metastatic CRC receiving regorafenib.

Appropriate dose of regorafenib based on body weight of colorectal cancer patients: a retrospective cohort study

PURPOSE

Previous randomized studies have shown a survival benefit of using regorafenib but a high rate of adverse events in unresectable colorectal cancer patients. To reduce these adverse events and improve the tolerability, we examined the appropriate dose of regorafenib based on body weight.

METHODS

We used a nationwide claims database in Japan and examined the efficacy and safety of regorafenib for patients with metastatic colorectal cancer between groups divided by body weight (60 kg) and median average dose (120 mg) between 2013 and 2018. We also assessed overall survival (OS) and adverse events between these groups.

RESULTS

We identified 2530 Japanese patients (heavy weight/high dose: 513, light weight/low dose: 921, heavy weight/low dose: 452, and light weight/high dose: 644). There was no significant difference in the adverse events and OS after inverse probability treatment weighting (IPTW) adjustment between heavy weight/high dose group and light weight/low dose group (hazard ratio, HR=0.97). Among the light-weight patients, higher average dose was associated with shorter OS (IPTW adjusted HR=1.21, 95% CI 1.05 - 1.39, Table 3) while among the heavy-weight patients, there was no significant difference in OS between high and low dose groups (IPTW adjusted HR=1.14, 95% CI 0.95 - 1.37).

CONCLUSION

The findings suggest that a low dose of regorafenib for light-weight patients may be as safe and effective as high doses for heavy-weight patients. Further studies should be conducted to identify an appropriate dose based on each patient's physique and condition.

Efficacy and Safety of Regorafenib with or without PD-1 Inhibitors as Second-Line Therapy for Advanced Hepatocellular Carcinoma in Real-World Clinical Practice

Background

Regorafenib is the first oral targeted drug as a second-line agent in patients with advanced hepatocellular carcinoma (HCC) who progressed on sorafenib treatment. Recently, several studies demonstrated that the combination of regorafenib and PD-1 inhibitors showed a synergistic effect. Our study aimed to evaluate the efficacy of regorafenib with PD-1 inhibitors (RP) and regorafenib alone (R) as second-line treatment for advanced HCC.

Methods

From October 2018 to January 2022, our retrospective study evaluated advanced HCC patients who received regorafenib with PD-1 inhibitors or regorafenib alone as a second-line treatment at the Second Affiliated Hospital of Nanchang University, China. The efficacy and safety were compared between RP and R groups.

Results

In total, 78 patients were enrolled in our study and were separated into two groups – RP group (48) and R group (30) – according to the criteria. The ORR of RP group and R group was 18.8% and 10%, respectively, and the DCR was 66.7% and 43.3%, respectively. The RP group had a longer mPFS (5.9 months vs 3.0 months, P<0.001) and mOS (12.9 months vs 10.3 months, P=0.010) than the R group. Regorafenib monotherapy is an independent prognostic factor for OS and PFS. In OS, subgroup analysis showed that patients with AFP ≥ 400ng/mL, BCLC C stage and extrahepatic metastasis may benefit from RP, while in PFS, subgroup analysis showed that patients with BCLC C stage, AFP ≥ 400ng/mL, extrahepatic metastasis, ALBI ≥-2.60 and first-line treatment of sorafenib may benefit from RP. The incidence of grade 3/4 adverse reaction in the two groups was 22.9% and 23.3%, respectively, with no significant statistically difference (P=0.966).

Conclusion

In the second-line therapy of advanced HCC, compared to regorafenib alone, the combination of regorafenib and PD-1 inhibitors showed promising efficacy and tolerable drug toxicity.

Clinical epidemiology and pharmacoepidemiology studies with real-world databases

Hospital-based registry data, including patients' information collected by academic societies or government based research groups, were previously used for clinical research in Japan. Now, real-world data routinely obtained in healthcare settings are being used in clinical epidemiology and pharmacoepidemiology. Real-world data include a database of claims originating from health insurance associations for reimbursement of medical fees, diagnosis procedure combinations databases for acute inpatient care in hospitals, a drug prescription database, and electronic medical records, including patients' medical information obtained by doctors, derived from electronic records of hospitals. In the past ten years, much evidence of clinical epidemiology and pharmacoepidemiology studies using real-world data has been accumulated. The purpose of this review was to introduce clinical epidemiology and pharmacoepidemiology approaches and studies using real-world data in Japan.

Dose reduction and discontinuation of standard-dose regorafenib associated with adverse drug events in cancer patients: a systematic review and meta-analysis

Background

Regorafenib (REG) is an oral multikinase inhibitor used in colorectal cancer, gastrointestinal stromal tumour and hepatocellular carcinoma. Several adverse events (AEs) are commonly reported during REG administration, and strategies for managing AEs in everyday clinical practice include supportive care, dose modifications and, when necessary, treatment withdrawal. We performed a systematic review and meta-analysis to assess the schedule treatment modifications of REG associated with AEs across randomized controlled clinical trials (RCTs).

Methods

Eligible studies included RCTs assessing standard dose REG versus placebo. Outcomes of interest included: AE-related permanent discontinuation, dose interruptions and dose reductions.

Results

We retrieved all the relevant RCTs through PubMed/Med, Cochrane library and EMBASE: 7 eligible studies involving a total of 2099 patients (Regorafenib: 1362; placebo: 737) were included in our analysis. The use of REG was associated with higher incidence and risk of all outcomes of interest when compared with placebo. The incidences of permanent discontinuation, dose interruptions and dose reductions in patients receiving REG were 9.7%, 57.2% and 47%, respectively, versus 3.3%, 16.7% and 7.7% of placebo group; compared with placebo, the summary relative risks (RRs) of permanent discontinuation, dose interruptions and dose reductions in REG arm were 2.80 (95% CI 1.85-4.22), 3.21 (95% CI 2.59-3.99) and 6.02 (95% CI 3.28-11.03), respectively.

Conclusions

Treatment with REG at the standard dose of 160 mg is associated with a significant increase in AE-related permanent discontinuation, dose interruptions and dose reductions. Prompt identification and management of AEs seem mandatory to obtain maximal benefit from REG treatment. In the current landscape, dose personalization of REG may have the potential to improve quality of life, minimize treatment discontinuation and maximize patient outcomes.