Oncogenic targets, magnitude of benefit, and market pricing of antineoplastic drugs

Genome-wide DNA methylation status is a predictor of the efficacy of anti-EGFR antibodies in the second-line treatment of metastatic colorectal cancer: Translational research of the EPIC trial

PURPOSE

The genome-wide DNA methylation status (GWMS) predicts of therapeutic response to anti-epidermal growth factor receptor (EGFR) antibodies in treating metastatic colorectal cancer. We verified the significance of GWMS as a predictive factor for the efficacy of anti-EGFR antibodies in the second-line treatment of metastatic colorectal cancer.

METHODS

Clinical data were obtained from a prospective trial database, and a genome-wide DNA methylation analysis was performed. GWMS was classified into high-methylated colorectal cancer (HMCC) and low-methylated colorectal cancer (LMCC). The patients were divided into subgroups according to the treatment arm (cetuximab plus irinotecan or irinotecan alone) and GWMS, and the clinical outcomes were compared between the subgroups.

RESULTS

Of the 112 patients, 58 (51.8%) were in the cetuximab plus irinotecan arm, and 54 (48.2%) were in the irinotecan arm; 47 (42.0%) were in the HMCC, and 65 (58.0%) were in the LMCC group regarding GWMS. Compared with the LMCC group, the progression-free survival (PFS) was significantly shortened in the HMCC group in the cetuximab plus irinotecan arm (median 1.4 vs. 4.1 months, p = 0.001, hazard ratio = 2.56), whereas no significant differences were observed in the irinotecan arm. A multivariate analysis showed that GWMS was an independent predictor of PFS and overall survival (OS) in the cetuximab plus irinotecan arm (p = 0.002, p = 0.005, respectively), whereas GWMS did not contribute to either PFS or OS in the irinotecan arm.

CONCLUSIONS

GWMS was a predictive factor for the efficacy of anti-EGFR antibodies in the second-line treatment of metastatic colorectal cancer.

Clinical Value of Molecular Targets and FDA-Approved Genome-Targeted Cancer Therapies

Importance

The number of new genome-targeted cancer drugs has increased, offering the possibility of personalized therapy, often at a very high cost.

Objective

To assess the validity of molecular targets and therapeutic benefits of US Food and Drug Administration-approved genome-targeted cancer drugs based on the outcomes of their corresponding pivotal clinical trials.

Design and Settings

In this cohort study, all genome-targeted cancer drugs that were FDA-approved between January 1, 2015, and December 31, 2022, were analyzed. From FDA drug labels and trial reports, key characteristics of pivotal trials were extracted, including the outcomes assessed.

Main Outcomes and Measures

The strength of evidence supporting molecular targetability was assessed using the European Society for Medical Oncology (ESMO) Scale for Clinical Actionability of Molecular Targets (ESCAT). Clinical benefit for their approved indications was evaluated using the ESMO-Magnitude of Clinical Benefit Scale (ESMO-MCBS). Substantial clinical benefit was defined as a grade of A or B for curative intent and 4 or 5 for noncurative intent. Molecular targets qualifying for ESCAT category level I-A and I-B associated with substantial clinical benefit by ESMO-MCBS were rated as high-benefit genomic-based cancer treatments.

Results

A total of 50 molecular-targeted drugs covering 84 indications were analyzed. Forty-five indications (54%) were approved based on phase 1 or phase 2 pivotal trials, 45 (54%) were supported by single-arm pivotal trials, and 48 (57%) were approved on the basis of subgroup analyses. By each indication, 46 of 84 primary end points (55%) were overall response rate (median [IQR] overall response rate, 57% [40%-69%]; median [IQR] duration of response, 11.1 [9.2-19.8] months). Among the 84 pivotal trials supporting these 84 indications, 38 trials (45%) had I-A ESCAT targetability, and 32 (38%) had I-B targetability. Overall, 24 of 84 trials (29%) demonstrated substantial clinical benefit via ESMO-MCBS. Combining these ratings, 24 of 84 indications (29%) were associated with high-benefit genomic-based cancer treatments.

Conclusions and Relevance

The results of this cohort study demonstrate that among recently approved molecular-targeted cancer therapies, fewer than one-third demonstrated substantial patient benefits at approval. Benefit frameworks such as ESMO-MCBS and ESCAT can help physicians, patients, and payers identify therapies with the greatest clinical potential.

A modified MethyLight assay predicts the clinical outcomes of anti-EGFR treatment in metastatic colorectal cancer

DNA methylation status correlates with clinical outcomes of anti‐epidermal growth factor receptor (EGFR) treatment. There is a strong need to develop a simple assay for measuring DNA methylation status for the clinical application of drug selection based on it. In this study, we collected data from 186 patients with metastatic colorectal cancer (mCRC) who had previously received anti‐EGFR treatment. We modified MethyLite to develop a novel assay to classify patients as having highly methylated colorectal cancer (HMCC) or low‐methylated colorectal cancer (LMCC) based on the methylation status of 16 CpG sites of tumor‐derived genomic DNA in the development cohort (n = 30). Clinical outcomes were then compared between the HMCC and LMCC groups in the validation cohort (n = 156). The results showed that HMCC had a significantly worse response rate (4.2% vs 33.3%; P = .004), progression‐free survival (median: 2.5 vs 6.6 mo, P < .001, hazard ratio [HR] = 0.22), and overall survival (median: 5.6 vs 15.5 mo, P < .001, HR = 0.23) than did LMCC in patients with RAS wild‐type mCRC who were refractory or intolerable to oxaliplatin‐ and irinotecan‐based chemotherapy (n = 101). The DNA methylation status was an independent predictive factor and a more accurate biomarker than was the primary site of anti‐EGFR treatment. In conclusion, our novel DNA methylation measurement assay based on MethyLight was simple and useful, suggesting its implementation as a complementary diagnostic tool in a clinical setting.

Efficacy, safety and tolerability of drugs studied in phase 3 randomized controlled trials in solid tumors over the last decade

Data suggest that for newly approved cancer drugs safety and tolerability are worse than in control arms of registration trials. Less is known about the balance between efficacy and toxicity of drugs studied in unselected phase 3 randomized controlled trials (RCTs) including those not resulting in regulatory approval. We searched Clinicaltrials.gov to identify phase 3 RCTs in patients with advanced breast, colorectal, lung, or prostate cancer completed between January 2005 and October 2016. We extracted efficacy and safety data from publications. For efficacy hazard ratios (HRs) for progression-free survival (PFS) and overall survival (OS) were extracted. For safety, we computed odds ratios (ORs) and 95% confidence intervals (CIs) for toxic death, treatment discontinuation without progression and commonly reported grade 3/4 adverse events (AEs). Data were then pooled in a meta-analysis. Of 377 RCTs identified initially, 143 RCTs comprising 88,603 patients were included in the analysis. Of these, 79 (57%) trials met their primary endpoint. Compared to control groups, both PFS (HR 0.80; 95% CI 0.78–0.82) and OS (HR 0.87; 95% CI 0.85–0.89) were improved with experimental drugs. Toxic death (OR 1.14; 95% CI 1.03–1.27), treatment discontinuation without progression (OR 1.64; 95% CI 1.56–1.71) and grade 3/4 AEs were also more common with experimental drugs compared to respective control group therapy. Just over half of phase 3 RCTs in common solid tumors met their primary endpoint and in nearly half, experimental therapy had worse safety compared to control arms.

Application of Value Frameworks to the Design of Clinical Trials: the Canadian Cancer Trials Group Experience

BACKGROUND

Use of value framework thresholds in the design of clinical trials may increase the proportion of randomized controlled trials (RCTs) that identify clinically meaningful advances for patients. Existing frameworks have not been applied to the research output of a cooperative cancer trials group. We apply value frameworks to the RCT output of the Canadian Cancer Trials Group (CCTG).

METHODS

Statistical design, study characteristics, and results of all published phase III trials of CCTG were abstracted. We applied the European Society for Medical Oncology-Magnitude of Clinical Benefit Scale (ESMO-MCBS) and American Society of Clinical Oncology Net Health Benefit (ASCO-NHB) to study results and the statistical power calculations to identify the proportion of all trials that were designed to detect a substantial clinical benefit.

RESULTS

During 1979-2017, CCTG published 113 phase III trials; 52.2% (59 of 113) of these trials were positive. Half (50.4%, 57 of 113) of trials were conducted in the palliative setting. In 37.2% (42 of 113) of trials the primary endpoint was overall survival; DFS or PFS was used in 38.9% (44 of 113) of trials. The ESMO-MCBS could be applied to the power calculation for 69 trials; 73.9% (51 of 69) of these trials were designed to detect an effect size that could meet ESMO-MCBS thresholds for substantial benefit. Among the 51 positive trials for which the ESMO-MCBS could be applied, 41.1% (21 of 51) met thresholds for substantial benefit.

CONCLUSIONS

Most CCTG phase III trials were designed to detect clinically meaningful differences in outcome, although less than half of positive trials met the threshold for substantial benefit. Application of value frameworks to the design of clinical trials is practical and may improve research efficiency and treatment options for patients.

Association Between Clinical Value and Financial Cost of Cancer Treatments: A Cross-Sectional Analysis

BACKGROUND

The cost of cancer treatment has increased significantly in recent decades, but it is unclear whether these costs have been associated with commensurate improvement in clinical value. This study aimed to assess the association between the cost of cancer treatment and 4 of the 5 NCCN Evidence Blocks (EB) measures of clinical value: efficacy of regimen/agent, safety of regimen/agent, quality of evidence, and consistency of evidence.

METHODS

This is a cross-sectional, observational study. We obtained NCCN EB ratings for all recommended, first-line, and/or maintenance treatments for the 30 most prevalent cancers in the United States and calculated direct pharmacologic treatment costs (drug acquisition, administration fees, guideline-concordant supportive care medications) using Medicare reimbursement rates in January 2019. We used generalized estimating equations to estimate the association between NCCN EB measures and treatment cost with clustering at the level of the treatment indication.

RESULTS

A total of 1,386 treatments were included. Among time-unlimited treatments (those administered on an ongoing basis without a predetermined stopping point), monthly cost was positively associated with efficacy ($3,036; 95% CI, $1,782 to $4,289) and quality of evidence ($1,509; 95% CI, $171 to $2,847) but negatively associated with safety (-$1,470; 95% CI, -$2,790 to -$151) and consistency of evidence (-$2,003; 95% CI, -$3,420 to -$586). Among time-limited treatments (those administered for a predetermined interval or number of cycles), no NCCN EB measure was significantly associated with treatment cost.

CONCLUSIONS

An association between NCCN EB measures and treatment cost was inconsistent, and the magnitude of the association was small compared with the degree of cost variation among treatments with the same EB scores. The clinical value of cancer treatments does not seem to be a primary determinant of treatment cost.

Lapatinib Activates the Kelch-Like ECH-Associated Protein 1-Nuclear Factor Erythroid 2-Related Factor 2 Pathway in HepG2 Cells

The receptor tyrosine kinase inhibitor lapatinib, indicated to treat patients with HER2-positive breast cancer in combination with capecitabine, can cause severe hepatotoxicity. Lapatinib is further associated with mitochondrial toxicity and accumulation of reactive oxygen species. The effect of lapatinib on the Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, the major cellular defense pathway against oxidative stress, has so far not been studied in detail. In the present study, we show that lapatinib (2–20 µM) activates the Keap1-Nrf2 pathway in HepG2 cells, a hepatocellular carcinoma-derived cell line, in a concentration-dependent manner upon 24 h of treatment. Lapatinib stabilized the transcription factor Nrf2 at concentrations ≥5 µM and caused its nuclear translocation. Well-established Nrf2 regulated genes (Nqo1, Gsta1, Gclc, and Gclm) were upregulated at lapatinib concentrations ≥10 µM. Furthermore, cellular and mitochondrial glutathione (GSH) levels increased starting at 10 µM lapatinib. As a marker of oxidative stress, cellular GSSG significantly increased at 10 and 20 µM lapatinib. Furthermore, the gene expression of mitochondrial Glrx2 and SOD2 were increased upon lapatinib treatment, which was also observed for the mitochondrial SOD2 protein content. In conclusion, lapatinib treatment for 24 h activated the Keap1-Nrf2 pathway in HepG2 cells starting at 10 μM, which is a clinically relevant concentration. As a consequence, treatment with lapatinib increased the mRNA and protein expression of antioxidative and other cytoprotective genes and induced GSH synthesis, but these measures could not completely block the oxidative stress associated with lapatinib.

Anticancer drugs approved by the Food and Drug Administration for gastrointestinal malignancies: Clinical benefit and price considerations

BACKGROUND

The cost of new anticancer drugs is rising. We aimed to assess the clinical benefit and price of anti-cancer drugs approved by the US Food and Drug Administration (FDA) for advanced gastrointestinal cancers.

METHODS

Drugs approved between 2006 and 2017 for advanced GI malignancies were identified from FDA.gov, and their updated supporting trial data were searched. Incremental clinical benefit was quantified by using ESMO Magnitude of Clinical Benefit Scale version 1.1 (grade 0-5) and ASCO Value Framework version 2 (score range -20 to 180). Higher scores indicate larger net benefit, and substantial benefit was defined as score 4 or 5 by the European Society for Medical Oncology (ESMO). The Micromedex REDBOOK was used to estimate the monthly average wholesale price (AWP) and total drug price (TDP) over the median treatment duration per patient. Clinical benefit, AWP and TDP of each drug class were assessed.

RESULTS

In total, 16 GI cancer drugs received FDA approval for 24 indications, including five monoclonal antibodies (mAbs), five oral targeted therapies (TT), two immunotherapeutics (IO), three cytotoxic chemotherapies (CT), and one recombinant fusion protein (aflibercept). Most supporting trials (82%) reported overall survival benefit of less than 3 months and no significant improvement in quality of life. Only five agents (including one TT and one IO) with 21% the of approved indications met the ESMO's threshold of substantial clinical benefit. Median incremental benefit scores of TT and IO were comparable to other drug classes. However their median TDP was much higher at $153 402 and $98 208, respectively, compared to $30 330 USD per patient for CT. The estimated TDP did not correlate with clinical benefit scores.

CONCLUSION

Most FDA-approved gastrointestinal cancer drugs do not meet the ESMO threshold of substantial clinical benefit. TT and IO are estimated to carry significant drug costs, and further cost analysis of these drugs is urgently needed.

Value-Added Decisions in Oncology

Registration of new anticancer drugs is decided too often not by their clinical value but by a p value. Approval is granted if the difference in an acceptable time-to-event outcome measure differs between experimental and control arms of a randomized controlled trial, such that the null hypothesis can be rejected based on a statistical test that meets the arbitrary criterion of p < .05. However, as stated by the American Statistical Association, a p value does not measure the size of an effect or the importance of a result; it does not provide a good measure of evidence related to a hypothesis, and policy decisions should not be made on the basis of whether a p value passes a specific threshold. Unfortunately, this statement is ignored by most journals, which emphasize p values in reporting results of clinical trials, and by regulatory agencies, such as the U.S. Food and Drug Administration and the European Medicines Agency; a significant p value is often a necessary and sufficient criterion for granting marketing approval. As a result, pharmaceutical companies often design large trials to increase the probability that a small difference in the primary outcome measure will be "significant." Moreover, the market price set for such drugs bears no relationship to the level of their benefit; drugs with small effects on outcome are sold at roughly the same price as "good drugs" that convey substantial benefit.

Repurposing old drugs in oncology: Opportunities with clinical and regulatory challenges ahead

WHAT IS KNOWN AND OBJECTIVE

In order to expedite the availability of drugs to treat cancers in a cost-effective manner, repurposing of old drugs for oncological indications is gathering momentum. Revolutionary advances in pharmacology and genomics have demonstrated many old drugs to have activity at novel antioncogenic pharmacological targets. We decided to investigate whether prospective studies support the promises of nonclinical and retrospective clinical studies on repurposing three old drugs, namely metformin, valproate and astemizole.

METHODS

We conducted an extensive literature search through PubMed to gather representative nonclinical and retrospective clinical studies that investigated the potential repurposing of these three drugs for oncological indications. We then searched for prospective studies aimed at confirming the promises of retrospective data.

RESULTS AND DISCUSSION

While evidence from nonclinical and retrospective clinical studies with these drugs appears highly promising, large scale prospective studies are either lacking or have failed to substantiate this promise. We provide a brief discussion of some of the challenges in repurposing. Principal challenges and obstacles relate to heterogeneity of cancers studied without considering their molecular signatures, trials with small sample size and short duration, failure consider issues of ethnicity of study population and effective antioncogenic doses of the drug studied.

WHAT IS NEW AND CONCLUSION

Well-designed prospective studies demonstrating efficacy are required for repurposing old drugs for oncology indications, just as they are for new chemical entities for any indication. Early and ongoing interactions with regulatory authorities are invaluable. We outline a tentative framework for a structured approach to repurposing old drugs for novel indications in oncology.

Impact of Availability of Companion Diagnostics on the Clinical Development of Anticancer Drugs

BACKGROUND

Companion diagnostics permit the selection of patients likely to respond to targeted anticancer drugs; however, it is unclear if the drug development process differs between drugs developed with or without companion diagnostics. Identification of differences in study design could help future clinical development.

PATIENTS AND METHODS

Anticancer drugs approved for use in solid tumors between 28 September 2000 and 4 January 2014 were identified using a search of the US FDA website. Phase III trials supporting registration were extracted from the drug label. Each published study was reviewed to obtain information about the phase I and II trials used for the development of the respective drug.

RESULTS

We identified 35 drugs and 59 phase III randomized trials supporting regulatory approval. Fifty-three phase I trials and 47 phase II trials were cited in the studies and were used to support the design of these phase III trials. The approval of drugs using a companion diagnostic has increased over time (p for trend 0.01). Expansion cohorts were more frequently observed with drugs developed with a companion diagnostic (62 vs. 20%; p = 0.005). No differences between drugs developed with or without a companion diagnostic were observed for the design of phase I and II studies.

CONCLUSIONS

The approval of drugs developed with a companion diagnostic has increased over time. The availability of a companion diagnostic was associated with more frequent use of phase I expansion cohorts comprising patients selected by the companion diagnostic.

Relevance of randomised controlled trials in oncology

Well-designed randomised controlled trials (RCTs) can prevent bias in the comparison of treatments and provide a sound basis for changes in clinical practice. However, the design and reporting of many RCTs can render their results of little relevance to clinical practice. In this Personal View, we discuss the limitations of RCT data and suggest some ways to improve the clinical relevance of RCTs in the everyday management of patients with cancer. RCTs should ask questions of clinical rather than commercial interest, avoid non-validated surrogate endpoints in registration trials, and have entry criteria that allow inclusion of all patients who are fit to receive treatment. Furthermore, RCTs should be reported with complete accounting of frequency and management of toxicities, and with strict guidelines to ensure freedom from bias. Premature reporting of results should be avoided. The bar for clinical benefit should be raised for drug registration, which should require publication and review of mature data from RCTs, post-marketing health outcome studies, and value-based pricing.

Failures in Phase III: Causes and Consequences

Phase III randomized controlled trials (RCT) in oncology fail to lead to registration of new therapies more often than RCTs in other medical disciplines. Most RCTs are sponsored by the pharmaceutical industry, which reflects industry's increasing responsibility in cancer drug development. Many preclinical models are unreliable for evaluation of new anticancer agents, and stronger evidence of biologic effect should be required before a new agent enters the clinical development pathway. Whenever possible, early-phase clinical trials should include pharmacodynamic studies to demonstrate that new agents inhibit their molecular targets and demonstrate substantial antitumor activity at tolerated doses in an enriched population of patients. Here, we review recent RCTs and found that these conditions were not met for most of the targeted anticancer agents, which failed in recent RCTs. Many recent phase III RCTs were initiated without sufficient evidence of activity from early-phase clinical trials. Because patients treated within such trials can be harmed, they should not be undertaken. The bar should also be raised when making decisions to proceed from phase II to III and from phase III to marketing approval. Many approved agents showed only better progression-free survival than standard treatment in phase III trials and were not shown to improve survival or its quality. Introduction of value-based pricing of new anticancer agents would dissuade the continued development of agents with borderline activity in early-phase clinical trials. When collaborating with industry, oncologists should be more critical and better advocates for cancer patients.

Strength of Validation for Surrogate End Points Used in the US Food and Drug Administration's Approval of Oncology Drugs

OBJECTIVE

To determine the strength of the surrogate-survival correlation for cancer drug approvals based on a surrogate.

PARTICIPANTS AND METHODS

We performed a retrospective study of the US Food and Drug Administration (FDA) database, with focused searches of MEDLINE and Google Scholar. Among cancer drugs approved based on a surrogate end point, we examined previous publications assessing the strength of the surrogate-survival correlation. Specifically, we identified the percentage of surrogate approvals lacking any formal analysis of the strength of the surrogate-survival correlation, and when conducted, the strength of such correlations.

RESULTS

Between January 1, 2009, and December 31, 2014, the FDA approved marketing applications for 55 indications based on a surrogate, of which 25 were accelerated approvals and 30 were traditional approvals. We could not find any formal analyses of the strength of the surrogate-survival correlation in 14 out of 25 accelerated approvals (56%) and 11 out of 30 traditional approvals (37%). For accelerated approvals, just 4 approvals (16%) were made where a level 1 analysis (the most robust way to validate a surrogate) had been performed, with all 4 studies reporting low correlation (r≤0.7). For traditional approvals, a level 1 analysis had been performed for 15 approvals (50%): 8 (53%) reported low correlation (r≤0.7), 4 (27%) medium correlation (r>0.7 to r<0.85), and 3 (20%) high correlation (r≥0.85) with survival.

CONCLUSIONS

The use of surrogate end points for drug approval often lacks formal empirical verification of the strength of the surrogate-survival association.

Update on Cardiovascular Safety of Tyrosine Kinase Inhibitors: With a Special Focus on QT Interval, Left Ventricular Dysfunction and Overall Risk/Benefit

We previously reviewed the cardiovascular safety of 16 tyrosine kinase inhibitors (TKIs), approved for use in oncology as of 30 September 2012. Since then, the indications for some of them have been widened and an additional nine TKIs have also been approved as of 30 April 2015. Eight of these nine are indicated for use in oncology and one (nintedanib) for idiopathic pulmonary fibrosis. This report is an update on the cardiovascular safety of those 16 TKIs, including the post-marketing data concerning their pro-arrhythmic effects, and reviews the cardiovascular safety of the nine new TKIs approved since (afatinib, cabozantinib, ceritinib, dabrafenib, ibrutinib, lenvatinib, nintedanib, ponatinib, and trametinib). As before, we focus on specific aspects of cardiovascular safety, namely their potential to induce QT interval prolongation, left ventricular (LV) dysfunction and hypertension but now also summarise the risks of arterial thromboembolic events (ATEs) associated with these agents. Of the newer TKIs, cabozantinib and ceritinib have been shown to induce a mild to moderate degree of QTc interval prolongation while cardiac dysfunction has been reported with the use of afatinib, dabrafenib, lenvatinib, ponatinib and trametinib. The label for axitinib was revised to include a new association with cardiac dysfunction. Hypertension is associated with cabozantinib, lenvatinib, nintedanib, ponatinib and trametinib. Ponatinib, within 10 months of its approval in December 2012, required voluntary (temporary) suspension of its marketing until significant safety revisions (restricted indication, additional warnings and precautions about the risk of arterial occlusion and thromboembolic events and amended dose) were made to its label. Compared with the previous 16 TKIs, more of the recently introduced TKIs are associated with the risk of LV dysfunction, and fewer with QT prolongation. Available data on morbidity and mortality associated with TKIs, together with post-marketing experience with lapatinib and ponatinib, emphasise the need for effective pharmacovigilance and ongoing re-assessment of their risk/benefit after approval of these novel agents. If not adequately managed, these cardiovascular effects significantly decrease the quality of life and increase the morbidity and mortality in a population already at high risk. Evidence accumulated over the last decade suggests that their clinical benefit, although worthwhile, is modest and extends only to progression-free survival and complete response without any effect on overall survival. During uncontrolled use in routine clinical practice, their risk/benefit is likely to be inferior to that perceived from highly controlled clinical trials.

Access to new cancer medicines in Australia: dispelling the myths and informing a public debate

Despite the high level of spending on cancer medicines in Australia, consumer organisations and the pharmaceutical industry often make claims of delayed or lack of access to new cancer medicines-claims that are frequently supported by prominent coverage in the Australian media. These claims, while morally and psychologically compelling, tend to ignore the complexity of medicines funding decisions. In this commentary we summarise the current situation regarding the registration and funding of cancer medicines in Australia, elucidate the main challenges associated with access to cancer medicines in the Australian context, and describe some of the steps that have been taken to address these challenges.

Population-based trends in systemic therapy use and cost for cancer patients in the last year of life

BACKGROUND

The use of systemic therapy near the end of life can expose cancer patients to severe toxicity for minimal survival gain and comes with a high cost. Early palliative care is recommended, but there is evidence that aggressive care remains common. To better understand those patterns, the present study set out to describe trends in systemic therapy use and cost for cancer patients in the last year of life.

METHODS

Using the BC Cancer Registry, a retrospective population-based cohort of cancer decedents (2002-2007) was identified and linked to systemic therapy records. The outcomes of interest were any systemic therapy use and total systemic therapy costs during the last year of life. Multiple logistic regression (systemic therapy use) and generalized linear regression (costs) were conducted, adjusting for age, sex, and survival. Subgroup analyses were performed for patients with primary colorectal, lung, prostate, or breast cancer.

RESULTS

From 2002 to 2007, use of systemic therapy in the last 12-4 months of life increased by 21% (95% ci: 10% to 33%); no significant change in use in the last 3 months of life was observed. Costs for both periods increased over time, by 48% (95% ci: 36% to 63%) and by 33% (95% ci: 19% to 49%) respectively. The trends varied across cancer sites, with the greatest increases being observed for lung and colorectal cancer patients.

CONCLUSIONS

The use and costs of systemic therapy have generally been increasing, putting pressure on health care providers and payers, but the quality-of-life implications for patients must be better understood.

Kinase inhibitors and monoclonal antibodies in oncology: clinical implications

Molecularly targeted cancer therapies, such as small-molecule kinase inhibitors and monoclonal antibodies, constitute a rapidly growing and an important part of the oncology armamentarium. Unlike conventional (cytotoxic) chemotherapeutics, targeted therapies were designed to disrupt cancer cell pathogenesis at specific biological points essential for the development and progression of the tumour. These agents were developed to disrupt specific targets with the aim of minimizing treatment burden compared with conventional chemotherapy. Nevertheless the increasingly common use of targeted therapies has revealed some unanticipated, often clinically significant toxic effects, as well as compromising effective palliative and end-of-life management approaches. Although patients and clinicians welcome improvements in cancer prognosis, these changes can also impact patient quality-of-life. Therefore, as demand for oncology expertise increases, physicians need to apprise themselves of targeted therapies and their clinical implications, including drug-specific side effects, impact on quality of life, and cost issues, especially in relation to end-of-life care. This Review provides a useful summary and guide for professionals treating patients with malignant diseases.

Impact of a Biomarker-Based Strategy on Oncology Drug Development: A Meta-analysis of Clinical Trials Leading to FDA Approval

BACKGROUND

In order to ascertain the impact of a biomarker-based (personalized) strategy, we compared outcomes between US Food and Drug Administration (FDA)-approved cancer treatments that were studied with and without such a selection rationale.

METHODS

Anticancer agents newly approved (September 1998 to June 2013) were identified at the Drugs@FDA website. Efficacy, treatment-related mortality, and hazard ratios (HRs) for time-to-event endpoints were analyzed and compared in registration trials for these agents. All statistical tests were two-sided.

RESULTS

Fifty-eight drugs were included (leading to 57 randomized [32% personalized] and 55 nonrandomized trials [47% personalized], n = 38 104 patients). Trials adopting a personalized strategy more often included targeted (100% vs 65%, P < .001), oral (68% vs 35%, P = .001), and single agents (89% vs 71%, P = .04) and more frequently permitted crossover to experimental treatment (67% vs 28%, P = .009). In randomized registration trials (using a random-effects meta-analysis), personalized therapy arms were associated with higher relative response rate ratios (RRRs, compared with their corresponding control arms) (RRRs = 3.82, 95% confidence interval [CI] = 2.51 to 5.82, vs RRRs = 2.08, 95% CI = 1.76 to 2.47, adjusted P = .03), longer PFS (hazard ratio [HR] = 0.41, 95% CI = 0.33 to 0.51, vs HR = 0.59, 95% CI = 0.53 to 0.65, adjusted P < .001) and a non-statistically significantly longer OS (HR = 0.71, 95% CI = 0.61 to 0.83, vs HR = 0.81, 95% CI = 0.77 to 0.85, adjusted P = .07) compared with nonpersonalized trials. Analysis of experimental arms in all 112 registration trials (randomized and nonrandomized) demonstrated that personalized therapy was associated with higher response rate (48%, 95% CI = 42% to 55%, vs 23%, 95% CI = 20% to 27%, P < .001) and longer PFS (median = 8.3, interquartile range [IQR] = 5 vs 5.5 months, IQR = 5, adjusted P = .002) and OS (median = 19.3, IQR = 17 vs 13.5 months, IQR = 8, Adjusted P = .04). A personalized strategy was an independent predictor of better RR, PFS, and OS, as demonstrated by multilinear regression analysis. Treatment-related mortality rate was similar for personalized and nonpersonalized trials.

CONCLUSIONS

A biomarker-based approach was safe and associated with improved efficacy outcomes in FDA-approved anticancer agents.

Clinical management of breast cancer heterogeneity

Traditionally, intertumour heterogeneity in breast cancer has been documented in terms of different histological subtypes, treatment sensitivity profiles, and clinical outcomes among different patients. Results of high-throughput molecular profiling studies have subsequently revealed the true extent of this heterogeneity. Further complicating this scenario, the heterogeneous expression of the oestrogen receptor (ER), progesterone receptor (PR), and HER2 has been reported in different areas of the same tumour. Furthermore, discordance, in terms of ER, PR and HER2 expression, has also been reported between primary tumours and their matched metastatic lesions. High-throughput molecular profiling studies have confirmed that spatial and temporal intratumour heterogeneity of breast cancers exist at a level beyond common expectations. We describe the different levels of tumour heterogeneity, and discuss the strategies that can be adopted by clinicians to tackle treatment response and resistance issues associated with such heterogeneity, including a rationally selected combination of agents that target driver mutations, the targeting of deleterious passenger mutations, identifying and eradicating the 'lethal' clone, targeting the tumour microenvironment, or using adaptive treatments and immunotherapy. The identification of the most-appropriate strategies and their implementation in the clinic will prove highly challenging and necessitate the adoption of radically new practices for the optimal clinical management of breast malignancies.

Risk of incremental toxicities and associated costs of new anticancer drugs: a meta-analysis

PURPOSE

There are increasing reports of rare but serious toxicities caused by new anticancer drugs, and there are costs associated with their management.

METHODS

We identified anticancer drugs approved by the U.S. Food and Drug Administration from 2000 to 2011 and pivotal trials supporting their registration. Twelve frequent grade 3 to 4 adverse event (AEs) were weighted and pooled in a meta-analysis. Estimates of incremental drug prices and incremental costs for management of AEs were calculated according to type of new agent based on target specificity.

RESULTS

We identified 41 studies comprising 27,539 patients and evaluating 19 experimental drugs. Agents directed against a specific molecular target on cancer cells had a lower incidence of grade 3 to 4 toxicities compared with controls (median risk ratio [RR], 0.67; P = .22), whereas less-specific targeted agents, including angiogenesis inhibitors (median RR, 3.39; P < .001) and chemotherapeutic agents (median RR, 1.73; P < .001), were more toxic. Risk was increased regardless of whether the control arm contained active treatment (RR, 2.11; P < .001) or not (RR, 3.02; P < .001). Median incremental drug price for experimental agents was $6,000 per patient per month. Median cost of managing toxicity was low compared with drug costs but higher than controls for treatment with less-specific targeted agents and chemotherapies.

CONCLUSION

Newly approved anticancer drugs are associated with increased toxicity, except for agents with a specific molecular target on cancer cells. Management of toxicity leads to a small increase in overall cost of treatment. Frequency of toxicity and associated costs are likely higher in less-selected patients treated in general oncologic practice. Development of biomarker-driven agents should be encouraged.

Evolution of costs of cancer drugs in a Portuguese hospital

AIM: To analyze the costs of cancer drugs administered in a Portuguese Hospital compared with the Karolinska Institute study.

METHODS: To evaluate spending on cancer drugs, we retrospectively analyzed data on the overall costs of cancer drugs, obtained at the Department of Medical Oncology of the Centro Hospitalar de Entre Douro e Vouga, between 2004 and 2010. In this comparative study we selected only drugs belonging to the following groups: chemotherapy, targeted therapy, immunotherapy and endocrine therapy. The selected drugs were further grouped according to their market placement year: ≤ 1998, 1999 to 2002, 2003 to 2005, and 2006 to 2010. Drugs used as supportive therapy and bisphosphonates were excluded.

RESULTS: The overall costs of cancer drugs increased gradually between 2004 and 2008 (from €1911947 to €3666284), with an increase in the number of patients treated during this period. The expenditure decreased in 2009 (€3438155) and increased again in 2010 (€3673116), but the costs increment was not the same as in previous years. Chemotherapy and targeted therapy were responsible for most of the expenditure. Drugs placed on the national market before 1999 accounted for more than 50% of the expenditure up to 2007. From 2008, these drugs represented less than 50% of the total expenditure. Cancer drugs placed between 1999 and 2002 accounted for 25%-35% of the costs in all the years studied, while drugs placed between 2003 and 2005 accounted for less than 30%. Drugs placed between 2006 and 2010 were responsible for less than 10% of the expenditure.

CONCLUSION: In this study, older drugs were responsible for most of the expenditure up to 2007, which is in agreement with the Karolinska study.

Activation of the PI3K/mTOR/AKT pathway and survival in solid tumors: systematic review and meta-analysis

BACKGROUND

Aberrations in the phosphatidylinositol 3-kinase (PI3K)/mammalian target of rapamycin (mTOR)/AKT pathway are common in solid tumors. Numerous drugs have been developed to target different components of this pathway. However the prognostic value of these aberrations is unclear.

METHODS

PubMed was searched for studies evaluating the association between activation of the PI3K/mTOR/AKT pathway (defined as PI3K mutation [PIK3CA], lack of phosphatase and tensin homolog [PTEN] expression by immunohistochemistry or western-blot or increased expression/activation of downstream components of the pathway by immunohistochemistry) with overall survival (OS) in solid tumors. Published data were extracted and computed into odds ratios (OR) for death at 5 years. Data were pooled using the Mantel-Haenszel random-effect model.

RESULTS

Analysis included 17 studies. Activation of the PI3K/mTOR/AKT pathway was associated with significantly worse 5-year survival (OR:2.12, 95% confidence intervals 1.42-3.16, p<0.001). Loss of PTEN expression and increased expression/activation of downstream components were associated with worse survival. No association between PIK3CA mutations and survival was observed. Differences between methods for assessing activation of the PI3K/mTOR/AKT pathway were statistically significant (p = 0.04). There was no difference in the effect of up-regulation of the pathway on survival between different cancer sites (p = 0.13).

CONCLUSION

Activation of the PI3K/AKT/mTOR pathway, especially if measured by loss of PTEN expression or increased expression/activation of downstream components is associated with poor survival. PIK3CA mutational status is not associated with adverse outcome, challenging its value as a biomarker of patient outcome or as a stratification factor for patients treated with agents acting on the PI3K/AKT/mTOR pathway.

Applications for oncologic drugs: a descriptive analysis of the oncologic drugs advisory committee reviews

BACKGROUND

Despite advances in cancer research, the majority of drug applications submitted to the U.S. Food and Drug Administration (FDA) are not approved. It is important to identify the concerns of the Oncologic Drugs Advisory Committee (ODAC) from rejected applications.

METHODS

All applications referred to the ODAC from 2001 to 2012 were reviewed.

RESULTS

Of 46 applications, 31 (67%) were for full and 15 (33%) were for supplemental approval, 34 (74%) were for solid and 12 (26%) were for hematologic tumors. In all, 22 (48%) were not approved. ODAC comments addressed missing or inadequate data (65%), excessive toxicity (55%), inappropriate study endpoints (45%), poor study design (40%), and insufficient sample size (30%). To define efficacy, 19 applications used response rates (RR) (median = 38%), and 19 applications used hazard ratios (HR) (median = 0.67). For all organ systems combined, the median cumulative grade 3 or 4 toxicity was 64%. Drugs with higher RR, lower HR, and lower toxicity were more likely to be approved versus other drugs (89% vs. 45%; p = .02). Over time (2001-2004, 2005-2008, 2009-2012), there was an increase in the following: number of applications submitted for review (from 11 to 12 to 23, respectively), number of approvals (from 6 to 6 to 12, respectively), and proportion of trials using progression-free survival as a primary endpoint (from 0% to 50% to 70%, respectively; p = .01).

CONCLUSION

Of all applications, common ODAC concerns included inadequate data, excessive toxicity, and inappropriate study endpoints. Over time, there was an approximate doubling of FDA application submissions and approved oncology drugs.

Delivering maximum clinical benefit at an affordable price: engaging stakeholders in cancer care

Cancer costs continue to increase alarmingly despite much debate about how they can be reduced. The oncology community needs to take greater responsibility for our own practice patterns, especially when using expensive tests and treatments with marginal value: we cannot continue to accept novel therapeutics with very small benefits for exorbitant prices. Patients, payers, and pharmaceutical communities should be constructively engaged to communicate medically and economically possible goals, and eventually, to reduce use and costs. Diagnostic tests and treatments should have to show true value to be added to existing protocols. In this article, we discuss three key drivers of costs: end-of-life care patterns, medical imaging, and drugs. We propose health-care models that have the potential to decrease costs and discuss solutions to maintain clinical benefit at an affordable price.

Hepatotoxicity of tyrosine kinase inhibitors: clinical and regulatory perspectives

The introduction of small-molecule tyrosine kinase inhibitors (TKIs) in clinical oncology has transformed the treatment of certain forms of cancers. As of 31 March 2013, 18 such agents have been approved by the US Food and Drug Administration (FDA), 15 of these also by the European Medicines Agency (EMA), and a large number of others are in development or under regulatory review. Unexpectedly, however, their use has been found to be associated with serious toxic effects on a number of vital organs including the liver. Drug-induced hepatotoxicity has resulted in withdrawal from the market of many widely used drugs and is a major public health issue that continues to concern all the stakeholders. This review focuses on hepatotoxic potential of TKIs. The majority of TKIs approved to date are reported to induce hepatic injury. Five of these (lapatinib, pazopanib, ponatinib, regorafenib and sunitinib) are sufficiently potent in this respect as to require a boxed label warning. Onset of TKI-induced hepatotoxicity is usually within the first 2 months of initiating treatment, but may be delayed, and is usually reversible. Fatality from TKI-induced hepatotoxicity is uncommon compared to hepatotoxic drugs in other classes but may lead to long-term consequences such as cirrhosis. Patients should be carefully monitored for TKI-induced hepatotoxicity, the management of which requires individually tailored reappraisal of the risk/benefit. The risk is usually manageable by dose adjustment or a switch to a suitable alternative TKI. Confirmation of TKI-induced hepatotoxicity can present challenges in the presence of hepatic metastasis and potential drug interactions. Its diagnosis in a patient with TKI-sensitive cancer requires great care if therapy with the TKI suspected to be causal is to be modified or interrupted as a result. Post-marketing experience with drugs such as imatinib, lapatinib and sorafenib suggests that the hepatotoxic safety of all the TKIs requires diligent surveillance.

Benefit and harms of new anti-cancer drugs

Phase III randomized controlled trials (RCTs) assess clinically important differences in endpoints that reflect benefit to and harm of patients. Defining benefit of cancer drugs can be difficult. Overall survival and quality of life are the most relevant primary endpoints, but difficulty in measuring these mean that other endpoints are often used, although their surrogacy or clinical relevance has not always been established. In general, advances in drug development have led to numerous new drugs to enter the market. Pivotal RCT of several new drugs have shown that benefit appeared greater for targeted anticancer agents than for chemotherapeutic agents. This effect seems particularly evident with targeted agents evaluated in biomarker-driven studies. Unfortunately, new therapies have also shown an increase in toxicity. Such toxicity is not always evident in the initial reports of RCTs. This may be a result of a statistical inability to detect differences between arms of RCTs, or occasionally due to biased reporting. There are several examples where reports of new toxicities could only be found in drug labels. In some cases, the small improvement in survival has come at a cost of substantial excess toxicity, leading some to consider such therapy as having equipoise.

Tyrosine kinase inhibitors: their on-target toxicities as potential indicators of efficacy

Tyrosine kinase inhibitors (TKIs) have revolutionized the treatment of certain forms of cancers, raising hopes for many patients with otherwise unresponsive tumours. While these agents are generally well tolerated, clinical experience with them has highlighted their unexpected association with serious toxic effects on various organs such as the heart, lungs, liver, kidneys, thyroid, skin, blood coagulation, gastrointestinal tract and nervous system. Many of these toxic effects result from downstream inhibition of vascular endothelial growth factor or epidermal growth factor signalling in cells of normal organs. Many of these undesirable effects such as hypertension, hypothyroidism, skin reactions and possibly proteinuria are on-target effects. Since tyrosine kinases are widely distributed with specific functional roles in different organs, this association is not too surprising. Various studies suggest that the development of these on-target effects indicates clinically desirable and effective inhibition of the corresponding ligand-mediated receptor linked with oncogenesis. This is reflected as improved efficacy in the subgroup of patients who develop these on-target adverse effects compared with those who do not. Inevitably, issues arise with respect to the regulatory assessment of efficacy and risk/benefit of the TKIs as well as the clinical approach to managing patients who develop these effects. Routine subgroup analysis of efficacy data from clinical trials (patients with and without on-target toxicity) may enable more effective clinical use of TKIs since (i) discontinuing or reducing the dose of the TKI has a negative impact if the tumour is TKI-responsive; and (ii) it is usually possible to manage these undesirable on-target effects with conventional clinical approaches. Prospective studies are needed to investigate this proposition further.

Sticker shock

A recent plea by oncologists condemning inflated prices for some cancer drugs has ignited a debate on this topic between clinicians and pharmaceutical companies and highlights the need for a broader assessment of drug valuation.

Phase III trials of targeted anticancer therapies: redesigning the concept

Randomized phase III trials provide the gold-standard evidence for the approval of new drugs: an experimental treatment is compared with the current standard of care to identify clinically relevant differences in a predefined endpoint. However, there are several problems relating to the current role of phase III trials in drug development including the limited clinical benefit observed for some approved agents, the necessity for large trials to detect these differences, the inability of such trials to identify rare but important toxicities, and high cost. The design of phase III trials evaluating drug combinations, and those including biomarkers, presents additional challenges. Here, we review these problems and suggest that phase III trials with adaptive designs in selected prescreened populations could reduce these limitations.

Targeted agent use in cancer patients at the end of life

CONTEXT

The use of targeted therapy at the end of life has not been well characterized.

OBJECTIVES

To determine the frequency and predictors of targeted therapy use in the last days of life.

METHODS

All adult patients residing in the Houston area who died of advanced cancer between September 1, 2009 and February 28, 2010 and had contact with our institution within the last three months of life were included. We collected baseline demographics and data on chemotherapy and targeted agents.

RESULTS

Eight hundred sixteen patients were included: average age 62 years (range 21-97), female 48% and white 61%. The median interval between the last treatment and death was 47 (interquartile range [IQR] 21-97) days for targeted agents and 57 (IQR 26-118) days for chemotherapeutic agents. Within the last 30 days of life, 116 (14%) patients received targeted agents and 147 (18%) received chemotherapy. Regimens given in the last 30 days of life included a median of one (IQR 1-2) chemotherapeutic or targeted agent and 43 (5%) patients receiving targeted agents had concurrent chemotherapy. The most common targeted agents in the last 30 days of life were erlotinib (n = 25), bevacizumab (n = 20), rituximab (n = 11), gemtuzumab (n = 8), and temsirolimus (n = 8). On multivariate analysis, younger age (odds ratio [OR] 0.98 per year, P = 0.01), hematologic malignancy (OR = 6.1, P < 0.001), and lung malignancy (OR = 2.6, P = 0.05) were associated with increased targeted agent use in the last 30 days of life.

CONCLUSION

Targeted agents were used as often as chemotherapy at the end of life, particularly among younger patients and those with hematologic malignancies. Guidelines on targeted therapy use at the end of life are needed.

Targeted therapy in metastatic colorectal cancer -- an example of personalised medicine in action

In metastatic colorectal cancer (mCRC), an improved understanding of the underlying pathology and molecular biology has successfully merged with advances in diagnostic techniques and local/systemic therapies as well as improvements in the functioning of multidisciplinary teams, to enable tailored treatment regimens and optimized outcomes. Indeed, as a result of these advancements, median survival for patients with mCRC is now in the range of 20-24months, having approximately tripled in the last 20years. The identification of KRAS as a negative predictive marker for activity of epidermal growth factor receptor (EGFR)-targeted monoclonal antibodies (mAbs), such as panitumumab (Amgen, Thousand Oaks, USA) and cetuximab (ImClone, Branchburg, USA), has perhaps had the greatest impact on patient management. This meant that, for the first time, mCRC patients unlikely to respond to a targeted therapy could be defined ahead of treatment. Ongoing controversies such as whether patients with KRAS G13D- (or BRAF V600-) mutated tumours can still respond to EGFR-targeted mAbs and the potential impact of inter- and intra-tumour heterogeneity on tumour sampling show that the usefulness of KRAS as a biomarker has not yet been exhausted, and that other downstream biomarkers should be considered. Conversely, a predictive biomarker for anti-angiogenic agents such as bevacizumab (Genentech, San Francisco, USA) in the mCRC setting is still lacking. In this review we will discuss the discovery and ongoing investigation into predictive biomarkers for mCRC as well as how recent advances have impacted on clinical practice and ultimately the overall cost of treatment for these patients.

The price we pay for progress: a meta-analysis of harms of newly approved anticancer drugs

PURPOSE

Registration of new anticancer drugs is usually based on results of randomized controlled trials (RCTs) showing improved efficacy when compared with standard therapy. There is relatively less emphasis on toxicity. In our study, we analyze serious toxicities of newly approved anticancer drugs reported in pivotal RCTs used for drug registration.

PATIENTS AND METHODS

We identified RCTs evaluating agents for the treatment of solid tumors approved by the US Food and Drug Administration between 2000 and 2010. Odds ratios (OR) and 95% CI were computed for three end points of safety and tolerability: treatment-related death, treatment-discontinuation related to toxicity, and grade 3 or 4 adverse events (AEs). These were then pooled in a meta-analysis. Correlations between these end points and the hazard ratios for overall survival (OS) and progression-free survival (PFS) were also assessed.

RESULTS

Thirty-eight RCTs were analyzed. Compared with control groups, the odds of toxic death was greater for new agents (OR, 1.40; 95% CI, 1.15 to 1.70; P < .001) as were the odds of treatment-discontinuation (OR, 1.33; 95% CI, 1.22 to 1.45, P < .001). Grade 3 or 4 AEs (OR, 1.52; 95% CI, 1.35 to 1. 71; P < .001) were also more common with new agents, especially nonhematologic AEs such as diarrhea, skin reactions, and neuropathy. There were no significant correlations between safety end points and OS or PFS.

CONCLUSION

New anticancer agents that lead to improvements in time-to-event end points also increase morbidity and treatment-related mortality. The balance between efficacy and toxicity may be less favorable in clinical practice because of selection of fewer patients with good performance status and limited comorbidities. Patients' baseline health characteristics should be considered when choosing therapy.