Treatment According to a Comprehensive Molecular Profiling Can Lead to a Better Outcome in Heavily Pretreated Patients With Metastatic Cancer: Data of a Pooled Analysis

Trametinib in Patients With NF1-, GNAQ-, or GNA11-Mutant Tumors: Results From the NCI-MATCH ECOG-ACRIN Trial (EAY131) Subprotocols S1 and S2

PURPOSE

NCI-MATCH is a precision medicine trial using genomic testing to allocate patients with advanced malignancies to targeted treatment subprotocols. This report combines two subprotocols evaluating trametinib, a MEK1/2 inhibitor, in patients with Neurofibromatosis 1 (NF1[S1] or GNA11/Q [S2]) altered tumors.

METHODS

Eligible patients had tumors with deleterious inactivating NF1 or GNA11/Q mutations by the customized Oncomine AmpliSeq panel. Prior MEK inhibitor treatment was excluded. Glioblastomas (GBMs) were permitted, including malignancies associated with germline NF1 mutations (S1 only). Trametinib was administered at 2 mg once daily over 28-day cycles until toxicity or disease progression. Primary end point was objective response rate (ORR). Secondary end points included progression-free survival (PFS) at 6 months, PFS, and overall survival. Exploratory analyses included co-occurring genomic alterations and PTEN loss.

RESULTS

Fifty patients were eligible and started therapy: 46 with NF1 mutations (S1) and four with GNA11 mutations (S2). In the NF1 cohort, nonsense single-nucleotide variants were identified in 29 and frameshift deletions in 17 tumors. All in S2 had nonuveal melanoma and GNA11 Q209L variant. Two partial responses (PR) were noted in S1, one patient each with advanced lung cancer and GBM for an ORR of 4.3% (90% CI, 0.8 to 13.1). One patient with melanoma in S2 had a PR (ORR, 25%; 90% CI, 1.3 to 75.1). Prolonged stable disease (SD) was also noted in five patients (four in S1 and one in S2) with additional rare histologies. Adverse events were as previously described with trametinib. Comutations in TP53 and PIK3CA were common.

CONCLUSION

Although these subprotocols did not meet the primary end point for ORR, significant responses or prolonged SD noted in some disease subtypes warrants further investigation.

The progression-free survival ratio as outcome measure in recurrent ovarian carcinoma patients: Current and future perspectives

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The progression-free survival (PFS) ratio represents a meaningful outcome measure.

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The median PFS-ratio differs significantly between histological subtypes of ovarian carcinoma.

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Thresholds for clinical benefit should be adjusted for clinicopathological factors.

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Treatment response during PFS1 may result in a distorted view of the PFS-ratio.

Objective

Clinical efficacy of cytostatic anticancer agents can be determined with the progression-free survival (PFS) ratio. This outcome measure compares PFS achieved by a new treatment (PFS2) to the PFS of the most recent treatment on which the patient has experienced progression (PFS1). Clinical benefit has been defined as a PFS-ratio (PFS2/PFS1) > 1.3. However, in order to demonstrate significant benefit, trial designs require an assumption on the proportion of patients who reach this ratio during palliative options. For ovarian carcinoma, data is lacking to support this assumption. Therefore in this study, we assess the PFS-ratio in recurrent ovarian carcinoma patients treated with current palliative options.

Methods

We included 67 patients with recurrent high-grade serous (HGSC, 73.1%) or low-grade (LGOC, 26.9%) ovarian carcinoma. We determined the median PFS-ratio and investigated the association with clinicopathological characteristics.

Results

Overall, we observed a median PFS-ratio of 0.69. The proportion of patients with a PFS-ratio > 1.3 was 22.4%. For HGSC patients, the median PFS-ratio was significantly lower than for LGOC patients (respectively, 0.58 and 1.26, p = 0.007). Multivariate logistic regression analysis revealed that the LGOC subtype and CA125 tumor marker concentration were independent factors related to a PFS-ratio > 1.3.

Conclusions

Although the PFS-ratio represents a meaningful outcome measure in studies investigating cytostatic anticancer agents, we conclude that it is influenced by tumor histology and biological behavior. In future research, these factors should be taken into account when determining thresholds for clinical benefit in trial designs.

Moving Molecular Profiling to Routine Clinical Practice: A Way Forward?

Molecular profiling of a patient's tumor to guide targeted treatment selection offers the potential to advance patient care by improving outcomes and minimizing toxicity (by avoiding ineffective treatments). However, current development of molecular profile (MP) panels is often based on applying institution-specific or subjective algorithms to nonrandomized patient cohorts. Consequently, obtaining reliable evidence that molecular profiling is offering clinical benefit and is ready for routine clinical practice is challenging. In particular, we discuss here the problems with interpreting for clinical utility nonrandomized studies that compare outcomes in patients treated based on their MP vs those treated with standard of care, studies that compare the progression-free survival (PFS) seen on a MP-directed treatment to the PFS seen for the same patient on a previous standard treatment (PFS ratio), and multibasket trials that evaluate the response rates of targeted therapies in specific molecularly defined subpopulations (regardless of histology). We also consider some limitations of randomized trial designs. A two-step strategy is proposed in which multiple mutation-agent pairs are tested for activity in one or more multibasket trials in the first step. The results of the first step are then used to identify promising mutation-agent pairs that are combined in a molecular panel that is then tested in the step-two strategy-design randomized clinical trial (the molecular panel-guided treatment for the selected mutations vs standard of care). This two-step strategy should allow rigorous evidence-driven identification of mutation-agent pairs that can be moved into routine clinical practice.

Cost-comparison analysis of a multiplatform tumour profiling service to guide advanced cancer treatment

Background

Tumor profiling is increasingly used in advanced cancer patients to define treatment options, especially in refractory cases where no standard treatment is available. Caris Molecular Intelligence (CMI) is a multiplatform tumor profiling service that is comprehensive of next-generation sequencing (NGS) of DNA and RNA, immunohistochemistry (IHC) and in situ hybridisation (FISH). The aim of this study is to compare costs of CMI-guided treatment with prior or planned treatment options in correlation with outcome results.

Methods

Retrospective data from five clinical trials were collected to define the treatment decision prior to the receipt of the CMI report (n = 137 patients). A systematic review of treatment data from 11 clinical studies of CMI (n = 385 patients) allowed a comparison of planned vs actual (n = 137) and prior vs actual (n = 229) treatment costs.

Results

Treatment plan was changed in 88% of CMI-profiled cases. The actual CMI guided treatment cost per cycle was £995 in 385 treated patients. Planned treatment costs were comparable to actual treatment costs (£979 vs £945; p = 0.7123) and prior treatment costs were not significantly different to profiling-guided treatments (£892 vs £850; p = 0.631).

Conclusions

Caris Molecular Intelligence guided treatment cost per cycle was in the range of prior or planned treatment cost/cycle. Due to beneficial overall survival the additional cost of performing CMI's multiplatform testing to the treatment costs seems to be cost-effective.