Comparative Effectiveness of FOLFIRINOX Versus Gemcitabine and Nab-paclitaxel in Initially Unresectable Locally Advanced Pancreatic Cancer: A Population-based Study to Assess Subsequent Surgical Resection and Overall Survival

AIMS

First-line FOLFIRINOX (FOLinic acid, Fluorouracil, IRINotecan, and OXaliplatin) and gemcitabine plus nab-paclitaxel (GnP) have been publicly funded for patients with unresectable locally advanced pancreatic cancer (uLAPC) in Ontario, Canada. We examined the overall survival and surgical resection rate after first-line FOLFIRINOX or GnP and determined the association between resection and overall survival in patients with uLAPC.

MATERIALS AND METHODS

We conducted a retrospective population-based study including patients with uLAPC who received first-line treatment FOLFIRINOX or GnP from April 2015 to March 2019. The cohort was linked to administrative databases to ascertain demographic and clinical characteristics. Propensity score methods were used to balance differences between FOLFIRINOX and GnP. The Kaplan-Meier method was used to calculate overall survival. Cox regression was used to determine the association between receipt of treatment and overall survival, adjusting for time-dependent surgical resections.

RESULTS

We identified 723 patients with uLAPC (mean age = 65.8, 43.5% female) who received FOLFIRINOX (55.2%) or GnP (44.8%). The median overall survival and 1-year overall survival probability were higher for FOLFIRINOX (13.7 months, 54.6%) than for GnP (8.7 months, 34.0%). Post-chemotherapy surgical resection occurred in 89 (12.3%) patients (FOLFIRINOX: 74 [18.5%] versus GnP: 15 [4.6%]), with no difference in survival since surgery between FOLFIRINOX and GnP (P = 0.29). After adjusting time-dependent post-treatment surgical resection, FOLFIRINOX (inverse probability treatment weighting hazard ratio 0.72, 95% confidence interval 0.61, 0.84) was independently associated with improved overall survival.

CONCLUSIONS

In this real-world population-based study of patients with uLAPC, FOLFIRINOX was associated with improved survival and higher resection rates. FOLFIRINOX was associated with improved survival in patients with uLAPC after accounting for the effect of post-chemotherapy surgical resection, suggesting the benefit of FOLFIRINOX was not solely due to improving resectability.

Real-world Safety of Bevacizumab with First-line Combination Chemotherapy in Patients with Metastatic Colorectal Cancer: Population-based Retrospective Cohort Studies in Three Canadian Provinces

AIMS

To examine the real-world safety of adding bevacizumab to first-line irinotecan-based chemotherapy for patients with metastatic colorectal cancer (mCRC).

MATERIALS AND METHODS

Patients diagnosed with CRC in three Canadian provinces (Ontario, Saskatchewan and British Columbia) who received publicly funded bevacizumab and/or irinotecan from 2000 to 2016 were identified from cancer registries. Propensity score 1:1 matching (PSM) and inverse probability of treatment weighting (IPTW) were performed to contemporaneous and historical controls, adjusting for baseline demographic and clinical characteristics. Safety end points evaluated during first-line treatment plus 30 days included mortality within 30 days and all-cause-, chemotherapy- and bevacizumab-related hospitalisations. Chemotherapy- and bevacizumab-related visits were defined as hospitalisations for specific conditions commonly associated with chemotherapy (e.g. infections) or bevacizumab (e.g. arteriovenous thromboembolism) using most responsible diagnosis codes. In PSM and IPTW-weighted cohorts, we assessed event frequencies using odds ratios from logistic regressions and event rate ratios using negative binomial regression models. The results from each province and comparison were pooled using random-effects meta-analysis.

RESULTS

We identified 16 250 mCRC patients who received first-line irinotecan-based treatment. In PSM cohorts, bevacizumab was associated with fewer deaths within 30 days of treatment compared with contemporaneous (pooled odds ratio = 0.62; 95% confidence interval 0.50-0.75) and historical controls (pooled odds ratio = 0.73; 95% confidence interval 0.58-0.93). Hospitalisations were more frequent among patients treated with bevacizumab compared with historical controls but similar to contemporaneous controls. As patients receiving bevacizumab were exposed to a longer average treatment duration, across their full treatment duration, patients receiving bevacizumab had significantly lower rates of hospitalisations (contemporaneous pooled rate ratio = 0.56; 95% confidence interval 0.47-0.67; historical pooled rate ratio = 0.73; 95% confidence interval 0.56-0.95). Similar trends were observed for chemotherapy- and bevacizumab-related hospitalisations and in IPTW-weighted cohorts.

DISCUSSION

We did not observe any increase in rates of hospitalisation or death within 30 days of treatment among mCRC patients treated with bevacizumab plus chemotherapy versus chemotherapy alone; these findings should be interpreted with caution due to the risk of residual confounding.

Real-world cost-effectiveness of pertuzumab (P) with trastuzumab + chemo (T+Chemo) in patients (pts) with metastatic breast cancer (MBC): A population-based retrospective cohort study by the Canadian Real-world Evidence for Value in Cancer Drugs (CanREValue) collaboration

1048

Background: Addition of P to T+chemo for MBC pts has been shown to improve overall survival (OS) in a pivotal randomized trial (hazard ratio [HR] = 0.66, 95% CI: 0.52, 0.84) (Baselga et al., NEJM 2012). In Canada, the manufacturer submission to the health technology assessment agency estimated that P produced 0.64 life years gained (LYG) with an incremental cost-effectiveness ratio (ICER) of $187,376/LYG over 10 years (CADTH-pCODR, 2013). This retrospective cohort analysis aims to determine the comparative real-world population-based effectiveness and cost-effectiveness of P among MBC pts in Ontario, Canada. Methods: MBC pts were identified from the Ontario Cancer Registry and linked to the New Drug Funding Program database to identify receipt of treatment between 1/1/2008 and 3/31/2018. Cases received P-T-chemo after universal public funding of P (Nov 2013) and controls received T-chemo before. Demographic (age, socioeconomic, rurality) and clinical (comorbidities, prior adjuvant treatments, prior breast cancer surgery, prior radiation, stage at diagnosis, ER/PR status) characteristics were identified from linked admin databases balanced between cases and controls using propensity score matching. Kaplan-Meier methods and Cox regressions accounting for matched pairs were used to estimate median OS and HR. 5-year mean total costs from the public health system perspective were estimated from admin claims databases using established direct statistical methods and adjusted for censoring of both cost and effectiveness using inverse probability weighting. ICERs and 95% bootstrapped CIs were calculated, along with incremental net benefit (INB) at various willingness-to-pay values using net benefit regression. Results: We identified 1,823 MBC pts with 912 cases and 911 controls (mean age = 55 years), of which 579 pairs were matched. Cases had improved OS (HR = 0.66; 95% CI: 0.57, 0.78), with median 3.4 years, compared to controls median OS of 2.1. P provided an additional 0.63 (95% CI: 0.48 – 0.84) LYG at an incremental cost of $196,622 (95% CI: $180,774, $219,172), with a mean ICER = $312,147/LYG (95% CI: $260,752, $375,492). At threshold of $100,000/LYG, the INB was -$133,632 (95% CI: -$151,525, -$115,739) with < 1% probability of being cost-effective. Key drivers of incremental cost increase between groups included drug and cancer clinic costs. Conclusions: The addition of P to T-chemo for MBC increased survival but at significant costs. The ICER based on direct real-world data was higher than the initial economic model due to higher total costs for pts receiving P. This study demonstrated feasibility to derive ICER from person-level real-world data to inform cancer drug life-cycle health technology reassessment.

Are real-world patient-reported outcomes associated with survival in patients with advanced pancreatic cancer?

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Background: Advanced pancreatic cancer (APC) patients often have a substantial symptom burden. In Ontario, patients visiting cancer clinics routinely complete the Edmonton Symptom Assessment Scale (ESAS), which screens for 9 symptoms (scale: 0-10). Using ESAS, we explored the association between baseline patient-reported outcomes and overall survival (OS). Methods: APC Patients with ESAS records prior to receiving publicly-funded drugs from November 2008 to March 2016 were identified from Cancer Care Ontario’s New Drug Funding Program and Symptom Management databases. We examined 3 baseline composite ESAS scores: Total Symptom Distress Score (TSDS: all 9 symptoms), Physical Symptom Score (PHS: 6/9 symptoms), and Psychological Symptom Score (PSS: 2/9 symptoms); Composite scores greater than a threshold (defined as number of symptoms in composite score multiplied by clinically relevant score (≥4)) were categorized as High Symptom Burden (TSDS ≥ 36, PHS ≥ 24, PSS ≥ 8). The primary endpoint, OS, was assessed using Kaplan-Meier. Multivariable Cox models were used to adjust for age, gender, income, prior therapies (surgery, adjuvant gemcitabine, radiation), and Charlson's comorbidity. Analysis was repeated in a sub-cohort with identifiable ECOG status and stage. Results: We identified 2,199 APC patients (mean age 64 years, 55% male) with ESAS records prior to receiving gemcitabine (54%), FOLFIRINOX (40%) or gemcitabine/nab-paclitaxel (6%). Crude median survival was 4.5 and 7.3 months for patients with high and low TSDS burden, respectively (HR = 1.50, 95% CI: 1.36, 1.66). After adjustment with multivariable Cox model, high TSDS burden was associated with lower OS (HR = 1.47, 95% CI: 1.33, 1.63). Similar trends were observed for PHS and PSS. When adjusting for both PHS and PSS in a Cox model, only the effect of PHS remained significant. In the sub-cohort (n = 393), high TSDS burden (HR = 1.34, 95% CI: 1.04, 1.73) was associated with lower OS, after adjusting for ECOG and stage. Conclusions: Among APC patients, a higher burden of patient-reported symptoms, via ESAS, at baseline was associated with reduced OS. The effect was prominent for physical symptoms, even after adjusting for treatment, stage and ECOG.

Impact of novel chronic lymphocytic leukemia drugs on public spending

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Title: Impact Of Novel Chronic Lymphocytic Leukemia Drugs On Public Spending Background: Chronic lymphocytic leukemia (CLL) is a common hematologic malignancy that mainly affects the elderly. Over the past five years, the treatment pathway for CLL has dramatically changed with the emergence of multiple novel agents. In Ontario, Canada, the Ontario Drug Benefit (ODB) program and the New Drug Funding Program (NDFP) primarily provide public coverage for CLL drugs. Given advances in treatment, we evaluated utilization trends for publicly-funded CLL drugs over a five year period (fiscal years 2012/13 to 2016/17). Methods: Drugs with primary CLL indications funded under the two public funding programs (i.e., ODB and NDFP) by 16/17 were included (n = 6). Claims and costs data were obtained from the Institute for Clinical Evaluative Sciences and Cancer Care Ontario‘s datasets. Results: Over five years, expenditures on CLL drugs have increased approximately ten-fold (1000 percent), reaching nearly CAD 43 million (i.e., USD 32.8 million) in 16/17. In the front-line setting, spending on rituximab remained consistent over the five years. Spending on single agent bendamustine decreased with the introduction of obinutuzumab which became the main cost driver by 16/17. In the previously-treated CLL population, ibrutinib has dominated expenditures since it was funded in July 2015. By 16/17, ibrutinib accounted for approximately ninety eight percent of spending in the previously-treated population. Conclusions: In the past five years, public spending on CLL drugs increased rapidly and substantially with the introduction of four novel agents, and may continue to evolve as Canadian provinces consider funding additional indications or newer agents. These findings warrant exploring whether the incremental spending is providing survival benefit or improvement in patients’ quality of life in a real-world setting. Declaration of funding: None

Comparative effectiveness and safety of the implementation of universal public funding of FOLFIRINOX (FFX) and gemcitabine (G) + nab-paclitaxel (GnP) in advanced pancreatic cancer (APC): A population-based study

375

Background: FFX has been universally publicly funded in Ontario, Canada, for metastatic pancreatic cancer (mPC) and unresectable locally advanced pancreatic cancer (uLAPC) since 11/2011 and 04/2015, respectively. GnP has been publicly funded for uLAPC and mPC (APC) since 04/2015. We examined the real world comparative effectiveness and safety of implementing funding of FFX and GnP for patients with APC. Methods: Patients with APC who received first-line FFX, GnP, or G from 01/2008-03/2016 were identified in CCO’s New Drug Funding Program database and divided into 3 periods: 01/2008-10/2011 (P1), 11/2011-03/2015 (P2), and 04/2015-03/2016 (P3). Data were linked with the Ontario Cancer Registry and others to ascertain demographics, comorbidities, and outcomes. Matching weights of propensity score to simultaneously compare three periods were generated using multinomial logistic regression. Crude and adjusted survival analyses were conducted to assess overall survival (OS) using Kaplan-Meier and weighted Cox regression methods.Weighted negative binomial models were used to estimate rate ratios (RR) for all-cause hospitalization (H) and ED visits. Results: We identified 3696 patients (1250 in P1, 1891 in P2, 555 in P3) (overall mean age 65, female 46%). In P2, 49% received FFX. In P3, 53% received FFX and 35% received GnP. Median OS was 5.7, 7.0, and 7.5 months for P1, P2, and P3, respectively. Median OS for FFX and GnP in mPC were 8.8 and 5.5 months, respectively. OS was improved in P2 vs. P1 (HR = 0.84, 0.78-0.90) and in P3 vs. P2 (HR = 0.82, 0.73-0.92). ED visits were similar compared P2 vs. P1 (RR=1.02, p = 0.75) and P3 vs. P2 (RR=1.04, p = 0.48), and H was reduced in P2 vs. P1 (RR = 0.86, p = 0.01), but similar in P3 vs. P2 (RR = 0.98, p = 0.78). H for febrile neutropenia (FN) was increased in P2 vs. P1 (RR = 2.18, p = 0.04) but not in P3 vs. P2 (RR = 1.32, p = 0.45). Conclusions: Implementation of universal public funding of FFX for mPC improved OS and reduced the rates H overall, but increased FN-related H. Funding of FFX for uLAPC and GnP for APC improved OS without increased in ER and H.

Chemotherapy choice in advanced pancreatic cancer: What patient and disease factors influence prescription patterns?

327

Background: FOLFIRINOX (FFX), gemcitabine+nab-paclitaxel (GnP) and gemcitabine monotherapy (Gem)) are universally funded as first-line chemotherapy regimens for advanced pancreatic cancer (APC) in Ontario, Canada. However, there is scarce real-world data on factors that may influence choice of chemotherapy regimens in APC. Methods: Patients who received first-line chemotherapy for APC between April 2015-March 2016 in Ontario were identified from CCO’s New Drug Funding Program database and linked to the Ontario Cancer Registry and other provincial databases to ascertain baseline factors. Multinomial logistic regressions were used to examine the associations between the prescribed chemotherapy regimen and baseline factors. Results: 546 patients were identified, with a mean age of 65 and 43.6% female. 9.9% and 9.7% had received adjuvant gemcitabine and radiation treatment respectively. 17.6% had previous pancreatic resection. 68.3% had zero Charlson score and 30.6% had ECOG performance status (PS) of 0. 72.7% had metastatic disease. The majority of the patients received FFX (52.4%) compared to GnP (35.7%) and Gem (11.9%). Age and ECOG PS were strongly associated with choice of chemotherapy regimens. (See Table) Conclusions: In Ontario, increased patient age and worse ECOG PS are strongly associated with choice of Gem compared to GnP and FFX. Previous treatments and stage of disease also impact chemotherapy choice. Understanding how providers choose chemotherapy in APC aids in comprehending our practices. Odds ratio (OR) and p value from multinomial logistic regressions. [Table: see text]

Outcomes of FOLFIRINOX (FFX) and gemcitabine+nab-paclitaxel (GnP) in initially unresectable locally advanced pancreatic cancer (uLAPC): A population-based study

394

Background: Data regarding the benefits of FFX and GnP in patients (pts) with initially uLAPC is limited. FFX and GnP have been universally publicly funded for first-line uLAPC in Ontario, Canada, since April 2015. The aims of this study are to determine (1) the overall survival (OS) of pts receiving FFX and GnP, (2) the surgical conversion rate of FFX and GnP, and (3) whether resection is associated with better OS in pts with uLAPC in an unselected, real world population. Methods: All pts in Ontario who started first-line FFX, GnP or gemcitabine (G) for uLAPC between April 2015 and March 2016 were identified in Cancer Care Ontario’s New Drug Funding Program database. They were linked to the Ontario Cancer Registry and other population-based databases to ascertain baseline characteristics (age, sex, performance status (PS), locating of tumor, income quintile, and rural residence) and outcomes (pancreatic cancer resection and vital status). Crude and adjusted models of OS were generated using Kaplan-Meier the method and Cox regression. Surgical resection was modelled as a time-dependent variable to examine its association with OS. Results: We identified 147 pts with uLAPC (mean age = 65, 44% female, 31% ECOG PS 0, 61% PS 1, 60% pancreatic head). Ninety (61.2%), 40 (27.2%) and 17 (11.6%) patients were treated with FFX, GnP and G, respectively. With a median follow-up of 7.5 months, median OS was not reached. The 6-month OS rate was 87.8%, 75.1% and 76.4% for FFX, GnP and G, respectively (p = 0.33). Resection occurred in 12 (8.2%) patients, with 10 (11.1%) and 2 (5.0%) treated with FFX and GnP, respectively ( p= 0.34). Surgical resection after initial chemotherapy was not associated with better OS in multivariable analysis (HR 0.26, 95%CI 0.03-1.98, p= 0.19). Conclusions: Pts with uLAPC treated with FFX and GnP appeared to have a reasonable OS in the real world, with > 75% of pts alive at 6 months. Surgical conversion rate in this unselected population appeared to be less than other single institutional studies. The current findings do not appear to show an early surgical benefit, but longer follow-up will be required to assess the potential long-term benefit of surgery.

Systemic treatment patterns in small bowel and appendiceal adenocarcinomas (SBA and AA): A population-based study

242

Background: There is uncertainty regarding the optimal systemic treatment for patients with SBA and AA due to the limited available evidence for these uncommon malignancies and conflicting recommendations in existing guidelines. However, on the basis of biologic similarities between SBA, AA and colorectal cancer (CRC), common practice is to use the same systemic therapies as for CRC. We compared the utilization of chemotherapeutic agents for SBA and AA to that of CRC patients in Ontario, Canada. Methods: The provincial tumour registry in Ontario, Canada was used to identify patients diagnosed with SBA, AA or CRC from 2010-2014. Subsequent chemotherapy utilization and costs were captured from single-payer government administrative databases. We studied the use of oxaliplatin, irinotecan, capecitabine, bevacizumab, cetuximab, panitumumab, and raltitrexed, which are funded for CRC treatment. Patients were excluded if they had multiple primary cancer sites, morphology codes inconsistent with adenocarcinomas, or missing identification data. Statistical analyses were used to report and test patterns of utilization and average costs per patient. Results: Our cohort consisted of 30,946 patients over a 5-year period. On average, 160 and 80 patients were diagnosed annually in Ontario with SBA and AA, respectively, together representing less than 4% of the total diagnoses each year. Among SBA and AA patients, 30-40% initiated therapy with the selected systemic therapies, similar to the proportion in CRC. SBA and AA patients were less likely to receive adjuvant oxaliplatin (SBA 9%, AA 13%) compared to CRC (18%) patients, but more likely to use first and second-line oxaliplatin or irinotecan for metastatic disease. Bevacizumab was added to first-line therapy for SBA and AA patients in fewer cases than CRC (SBA 29%, 45% AA, 72% CRC). Third-line EGFR inhibitors panitumumab and cetuximab were used infrequently in all groups ( < 2% of those diagnosed). Average per patient costs were similar across disease sites (p > 0.05). Conclusions: On a population level, SBA and AA patients appear to be managed similarly to CRC patients and at similar cost. Future research will evaluate survival outcomes.