Adapting Health Technology Assessment agency standards for surrogate outcomes in early stage cancer trials: what needs to happen?

INTRODUCTION

An avalanche of early stage cancer clinical trials is coming. The majority of these solely use surrogate outcomes that have not been validated against a target outcome of interest (e.g. overall survival). Current HTA guidance on surrogate outcome validation are not methodologically or practically conducive to this scenario.

AREAS COVERED

We provide a high-level overview of methods, approaches, and conceptual thinking for making better use of limited evidence within early stage cancer HTA submissions. We outline regulatory and HTA issues and emphasize how evidence transitions from one to another, what major gaps currently exist, and how these may be bridged. We summarize current methodologies and practices, their pros and cons. We outline how complementary measurements strengthen evaluations and address fallacies and biases of conventional statistical methods for surrogate outcomes validation. The value of real-world data to support some of the necessary validity components is discussed. Lastly, we address the importance of the patient voice for better understanding which surrogate outcomes may appropriately inform HTA.

EXPERT OPINION

Conventional surrogate outcome validation represents a fraught and sub-optimal framework for HTA purposes, particularly for early stage cancer. Tools for optimizing use of limited evidence exist. Education of stakeholders is highly needed.

Real-world treatment patterns and survival outcomes for treated biliary tract cancer patients using administrative databases in Ontario

Background

There are limited data available on treatment patterns and outcomes of biliary tract cancers (BTCs) in Canada. The aim of this study was to understand treatment patterns, survival outcomes and healthcare resource use of BTC patients in Ontario, Canada.

Methods

We conducted a retrospective population-level study using administrative data of patients diagnosed with advanced or metastatic BTC between January 1, 2010 and December 31, 2019.

Results

A total of 2,142 BTC patients were identified; 702 (32.8%) with intrahepatic cholangiocarcinoma, 688 (32.1%) with extrahepatic cholangiocarcinoma, 363 (16.9%) with gallbladder cancer, 174 (8.1%) with ampulla of Vater cancer, and 215 (10.0%) with other types of BTC. In total, 1,314 patients (61.3%) were recurrent cases, and 828 (38.7%) were diagnosed with de novo advanced disease. A total of 1,727 patients (80.6%) received first-line systemic treatment of cisplatin plus gemcitabine (75.2%), FOLFOX [5-fluorouracil (5-FU), folinic acid (FA), and oxaliplatin] or FOLFIRI (5-FU, FA, and irinotecan) (11.5%), carboplatin plus gemcitabine (7.6%), or gemcitabine plus taxane (5.7%). Five hundred and twelve patients (29.6%) went on to receive a second-line treatment. Mean and median overall survival from diagnosis was 20.6 and 11.0 months, respectively. Mean and median overall survival from diagnosis was much higher among patients who received a systemic treatment at 23.8 and 14.1 months, respectively compared to 7.0 and 3.3 months, respectively for untreated patients (P<0.0001).

Conclusions

Platinum and gemcitabine combinations are the most common first-line treatments. However, only a small proportion of patients go on to receive subsequent treatments. Survival in treated patients is higher than that in untreated patients. Our findings highlight the unmet need for effective systemic therapies for BTC.

Real-world treatment patterns, clinical outcomes, and health care resource utilization in advanced unresectable hepatocellular carcinoma

BACKGROUND: The incidence of advanced unresectable hepatocellular carcinoma (HCC) is increasing in developed countries and the prognosis of advanced HCC remains poor. Real-world evidence of treatment patterns and outcomes can highlight the unmet clinical need. METHODS: We conducted a retrospective population-based cohort study of patients with advanced unresectable HCC diagnosed in Alberta, Canada (2008-2018) using electronic medical records and administrative claims data. A chart review was conducted on patients treated with systemic therapy to capture additional information related to treatment. RESULTS: A total of 1,297 advanced HCC patients were included of whom 555 (42.8%) were recurrent cases and the remainder were unresectable at diagnosis. Median age at diagnosis was 64 (range 21-94) years and 82.1% were men. Only 274 patients (21.1%) received first-line systemic therapy and, of those, 32 patients (11.7%) initiated second-line therapy. Nearly all of the patients received sorafenib (>96.4%) in first-line, and these patients had considerably higher median survival (12.23 months; 95% CI 10.72-14.10) compared with patients not treated with systemic therapy (2.66 months; 95% CI 2.33-3.12; log-rank p <0.001). Among patients treated with systemic therapy, overall survival was higher for recurrent cases, patients with Child-Pugh A functional status, and patients with HCV or multiple known HCC risk factors (p <0.05). CONCLUSIONS: In a Canadian real-world setting, patients who received systemic therapy had greater survival than those who did not, but outcomes were universally poor. These results underscore the need for effective front-line therapeutic options.

Glutamate Cysteine Ligase Catalytic Subunit Promoter Polymorphisms and Associations with Type 1 Diabetes Age-at-onset and GAD65 Autoantibody Levels

The purpose of this study was to test the hypothesis that glutamate cysteine ligase catalytic subunit (GCLC) promoter polymorphisms are susceptibility factors for type 1 diabetes (T1D), T1D age-at-onset and T1D autoantibodies. T1D patients and control subjects from the Swedish Childhood Diabetes Registry and the Swedish Diabetes Incidence Study registry were genotyped for two GCLC promoter polymorphisms; the GCLC -129 C to T single nucleotide polymorphism (GCLC -129 SNP) and the GCLC GAG trinucleotide repeat polymorphism (GCLC TNR). Glutamate decarboxylase antibody (GAD65Ab) positive T1D patients with the GCLC -129 SNP C/T genotype have increased GAD65Ab levels (p-value, <0.05) compared to the GCLC -129 SNP C/C genotype. T1D patients with an age-at-onset of 14-35 years who possess the GCLC -129 SNP T/T genotype have a higher GAD65Ab index than T1D patients with the GCLC -129 SNP C/C genotype (p-value <0.05). In addition, T1D patients with an age-at-onset of 14-35 years possess the GCLC TNR 7/8 genotype at a lower frequency than the control subjects (OR, 0.33, 95% CI, 0.13-0.82). The GCLC -129 SNP and GCLC TNR appear to be in linkage disequilibrium (p-value<0.0001). These results suggest that GCLC promoter polymorphisms may influence GAD65Ab levels and may influence the age at which T1D is diagnosed.