Category: Precision Oncology

FDA Approves ALUNBRIG® for First Line Treatment of ALK Positive Non Small Cell Lung Cancer

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SUMMARY: The FDA on May 22, 2020 approved approved ALUNBRIG® (Brigatinib) for the first-line treatment of patients with ALK-positive metastatic Non Small Cell Lung Cancer (NSCLC), as detected by an FDA-approved test. Lung cancer is the second most common cancer in both men and women and accounts for about 14% of all new cancers and 27% of all cancer deaths. The American Cancer Society estimates that for 2020, about 228, 820 new cases of lung cancer will be diagnosed and 135,720 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Non-Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers. Of the three main subtypes of NSCLC, 30% are Squamous Cell Carcinomas (SCC), 40% are Adenocarcinomas and 10% are Large Cell Carcinomas. With changes in the cigarette composition and decline in tobacco consumption over the past several decades, Adenocarcinoma now is the most frequent histologic subtype of lung cancer.

The discovery of rearrangements of the Anaplastic Lymphoma Kinase (ALK) gene in some patients with advanced NSCLC and adenocarcinoma histology, led to the development of agents such as XALKORI® (Crizotinib), ZYKADIA® (Ceritinib), ALECENSA® (Alectinib) and ALUNBRIG® (Brigatinib), with promising results. It has become clear that appropriate, molecularly targeted therapy for tumors with a molecular abnormality, results in the best outcomes. According to the US Lung Cancer Mutation Consortium (LCMC), two thirds of patients with advanced adenocarcinoma of the lung, have a molecular driver abnormality. The most common oncogenic drivers in patients with advanced adenocarcinoma of the lung are, KRAS in 25%, EGFR in 21% and ALK in 8% as well as other mutations in BRAF, HER2, AKT1 and fusions involving RET and ROS oncogenes. These mutations are mutually exclusive, and the presence of two simultaneous mutations, are rare.

The new approval for ALUNBRIG® was based on results from the Phase III ALTA 1L (ALK in Lung Cancer Trial of BrigAtinib in 1st Line) trial, which is a global, ongoing, randomized, open-label, comparative, multicenter study, in which investigators compared the efficacy and safety of ALUNBRIG® with XALKORI® (Crizotinib) in 275 patients with Stage IIIB/IV ALK positive, locally advanced or metastatic NSCLC, who have not received prior treatment with an ALK inhibitor, but may have received 1 prior regimen of chemotherapy or no chemotherapy in the advanced setting. Patients were randomized 1:1 to receive either ALUNBRIG® 180 mg orally once daily (N=137), with a 7-day lead-in period at 90 mg, or XALKORI® 250 mg orally twice daily (N=138). Crossover from the XALKORI® arm to receive ALUNBRIG® was permitted at BICR (Blinded Independent Review Committee)-assessed Progression Free Survival (PFS). The median age was 59 years, and 55% of patients were female. Twenty-nine percent had brain metastases at baseline with comparable pre-enrollment central nervous system (CNS) radiotherapy rates among both cohorts. Overall, 27% of patients had prior chemotherapy in the locally advanced or metastatic setting. The Primary endpoint was BIRC assessed PFS and Secondary endpoints included Objective Response Rate (ORR), Intracranial ORR, Intracranial PFS, Overall Survival (OS), safety, and tolerability.

At a median follow up of 25 months, it was noted that ALUNBRIG® reduced the risk of disease progression or death by 51% compared with XALKORI® (HR=0.49; P=0.0007), with a median PFS of 24 months as assessed by a BIRC versus 11 months for XALKORI®. The confirmed ORR as assessed by BIRC was 74% with ALUNBRIG® and 62% for XALKORI®. The median duration of response (DOR) was not reached, and 13.8 months with ALUNBRIG® and XALKORI®, respectively.

After more than two years of follow-up, ALUNBRIG® demonstrated superiority over XALKORI®, with significant anti-tumor activity observed, especially in patients with baseline brain metastases. The confirmed intracranial ORR for patients with measurable brain metastases at baseline, treated with ALUNBRIG® was 78% versus 26% for patients treated with XALKORI®. The median intracranial Duration of Response in confirmed responders with measurable brain metastases at baseline was Not Reached with ALUNBRIG® and 9.2 months with XALKORI®, respectively. The median intracranial PFS was 24 months with ALUNBRIG®, compared with 5.6 months for XALKORI®. ALUNBRIG® reduced the risk of intracranial disease progression or death by 69% in patients who had brain metastases at baseline (HR=0.31).

Additionally, patients in the ALUNBRIG® group also experienced significant improvements in Health-Related Quality of Life, with delay in the median time to worsening in Global Health Score by 27 months versus 8 months with XALKORI®, as well as delay in the time to worsening and prolonged duration of improvement in fatigue, nausea and vomiting, appetite loss, and emotional and social functioning. Further, the duration of improvement in QoL with ALUNBRIG® was Not Reached versus 12 months with XALKORI®.

It was concluded that ALUNBRIG® demonstrated a statistically and clinically significant improvement in Progression Free Survival when compared to XALKORI® in ALK inhibitor-naïve, ALK positive NSCLC, with superior efficacy especially among those with brain metastases at baseline.

Brigatinib vs crizotinib in patients with ALK inhibitor-naive advanced ALK+ NSCLC: Updated results from the phase III ALTA-1L trial. Camidge R, Kim HR, Ahn M, et al. Presented at the 2019 ESMO Asia Congress, November 23, 2019.

FDA Approves RUBRACA® for BRCA-Mutated Metastatic Castrate Resistant Prostate Cancer

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SUMMARY: The FDA on May 15, 2020, granted accelerated approval to RUBRACA® (Rucaparib) for patients with deleterious BRCA mutation (germline and/or somatic)-associated metastatic Castration-Resistant Prostate Cancer (mCRPC), who have been treated with Androgen Receptor-directed therapy and a taxane-based chemotherapy. Prostate cancer is the most common cancer in American men with the exclusion of skin cancer, and 1 in 9 men will be diagnosed with prostate cancer during their lifetime. It is estimated that in the United States, about 191,930 new cases of prostate cancer will be diagnosed in 2020 and 33,330 men will die of the disease.

The development and progression of Prostate cancer is driven by androgens. Androgen Deprivation Therapy (ADT) or testosterone suppression has therefore been the cornerstone of treatment of advanced Prostate cancer and is the first treatment intervention. Androgen Deprivation Therapies have included bilateral orchiectomy or Gonadotropin Releasing Hormone (GnRH) analogues, with or without first generation Androgen Receptor (AR) inhibitors such as CASODEX® (Bicalutamide), NILANDRON® (Nilutamide) and EULEXIN® (Flutamide) or with second-generation, anti-androgen agents, which include, ZYTIGA® (Abiraterone), XTANDI® (Enzalutamide) and ERLEADA® (Apalutamide). ZYTIGA® inhibits CYP17A1 enzyme and depletes adrenal and intratumoral androgens, thereby impairing AR signaling. XTANDI® and ERLEADA® compete with Testosterone and Dihydrotestosterone and avidly bind to the Androgen Receptor, thereby inhibiting AR signaling, and in addition inhibit translocation of the AR into the nucleus and thus inhibits the transcriptional activities of the AR. Approximately 10-20% of patients with advanced Prostate cancer will progress to Castration Resistant Prostate Cancer (CRPC) within five years during ADT, and over 80% of these patients will have metastatic disease at the time of CRPC diagnosis. The estimated mean survival of patients with CRPC is 9-36 months, and there is therefore an unmet need for new effective therapies.

DNA damage is a common occurrence in daily life by UV light, ionizing radiation, replication errors, chemical agents, etc. This can result in single and double strand breaks in the DNA structure which must be repaired for cell survival. The two vital pathways for DNA repair in a normal cell are BRCA1/BRCA2 and PARP. The PARP (Poly ADP Ribose Polymerase), family of enzymes include, PARP1, PARP2 and PARP3. BRCA1 and BRCA2 genes recognize and repair double strand DNA breaks via Homologous Recombination (HR) pathway. Homologous Recombination is a type of genetic recombination, and is a DNA repair pathway utilized by cells to accurately repair DNA double-stranded breaks during the S and G2 phases of the cell cycle, and thereby maintain genomic integrity. Homologous Recombination Deficiency (HRD) is noted following mutation of genes involved in HR repair pathway. At least 15 genes are involved in the Homologous Recombination Repair (HRR) pathway including BRCA1, BRCA2 and ATM genes. The BRCA1 gene is located on the long (q) arm of chromosome 17 whereas BRCA2 is located on the long arm of chromosome 13. BRCA1 and BRCA2 are tumor suppressor genes and functional BRCA proteins therefore repair damaged DNA, and play an important role in maintaining cellular genetic integrity. They regulate cell growth and prevent abnormal cell division and development of malignancy.

Recently published data has shown that deleterious germline and/or somatic mutations in BRCA1, BRCA2, ATM, or other Homologous Recombination DNA-repair genes, are present in about 25% of patients with advanced prostate cancer, including mCRPC. Mutations in BRCA1 and BRCA2 also account for about 20-25% of hereditary breast cancers, about 5-10% of all breast cancers, and 15% of ovarian cancers. BRCA mutations can either be inherited (Germline) and present in all individual cells or can be acquired and occur exclusively in the tumor cells (Somatic). Somatic mutations account for a significant portion of overall BRCA1 and BRCA2 aberrations. Loss of BRCA function due to frequent somatic aberrations likely deregulates HR pathway, and other pathways then come in to play, which are less precise and error prone, resulting in the accumulation of additional mutations and chromosomal instability in the cell, with subsequent malignant transformation. HRD therefore indicates an important loss of DNA repair function. PARP is a related enzymatic pathway that repairs single strand breaks in DNA. In a BRCA mutant, the cancer cell relies solely on PARP pathway for DNA repair. In the presence of a PARP inhibitor, there is synthetic lethality because of the loss of both repair pathway genes, leading to cell death. Thus PARP inhibitors are only harmful to cancer cells.MOA-of-RUBRACA

RUBRACA® is an oral, small molecule inhibitor of Poly-Adenosine diphosphate [ADP] Ribose Polymerase (PARP), presently approved by the FDA for ovarian, fallopian tube or primary peritoneal cancers. This recent FDA approval for prostate cancer patients was based on TRITON2, which is an ongoing international, multicenter, open-label, single arm, Phase II trial, in patients with BRCA-mutated mCRPC, who had been treated with Androgen Receptor-directed therapy and taxane-based chemotherapy. In this study, 115 mCRPC patients with either germline or somatic BRCA mutations were enrolled, of whom 62 patients had measurable disease at baseline. Patients received RUBRACA® 600 mg orally twice daily and concomitant GnRH analog or had prior bilateral orchiectomy. Treatment was continued until disease progression or unacceptable toxicity. The median age was 73 years, majority of patients had an ECOG performance status of 0 or 1, 18% of patients had lung metastases, 21% had liver metastases, 24% had metastases to lymph nodes alone and 40% had 10 or more bone lesions at baseline. The major efficacy outcomes of the study were Objective Response Rate (ORR) and Duration of Response (DOR) in the 62 patients with measurable disease. The median duration of follow up was 13.1 months

The confirmed ORR was 44% and the median DOR was not evaluable. Fifty six percent (56%) of patients with confirmed Objective Responses had a DOR of 6 months or more.

It was concluded that RUBRACA® demonstrates promising efficacy in patients with mCRPC with deleterious BRCA mutations. TRITON3 study is evaluating RUBRACA® versus physician’s choice of second-line AR-directed therapy or Docetaxel, in chemotherapy-naïve patients with mCRPC and alterations in BRCA1/2, who progressed on one prior AR-directed therapy.

ESMO 2019: Preliminary Results from the TRITON2 Study of Rucaparib in Patients with DNA Damage Repair-deficient mCRPC: Updated Analyses. Abida W, Campbell D, Patnaik A, et al. 2019 ESMO Annual Meeting, #ESMO19, 27 Sept – 1 Oct 2019 in Barcelona, Spain.

FDA Approves TABRECTA® for Metastatic Non-Small Cell Lung Cancer

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SUMMARY: The FDA on May 6, 2020, granted accelerated approval to TABRECTA® (Capmatinib) for adult patients with metastatic Non-Small Cell Lung Cancer (NSCLC), whose tumors have a mutation that leads to Mesenchymal-Epithelial Transition (MET) exon 14 skipping, as detected by an FDA-approved test. The FDA also approved the FoundationOne CDx assay (Foundation Medicine, Inc.) as a companion diagnostic for TABRECTA®.

MET is a widely expressed Receptor Tyrosine Kinase and plays a pivotal role in cell growth, proliferation and survival. The MET gene encodes for a protein known as the Hepatocyte Growth Factor (HGF) Receptor. Upon binding by Hepatocyte Growth Factor (HGF), the HGF Receptor is activated, with resulting activation of the downstream RAS/RAF/MEK/ERK and PI3K/AKT/mTOR signaling pathways, thereby serving different important biological functions. Alterations in the MET gene leading to abnormal MET signaling, has been identified in different types of cancers including thyroid, lung, breast, liver, colon, kidney, ovary and gastric carcinoma.MET-Signaling-Pathway

Two key MET alterations include MET exon 14 skipping mutations and MET amplification. MET exon 14 skipping mutations occur in approximately 5% of NSCLC patients with enrichment in sarcomatoid lung cancers (22%). MET exon 14 skipping mutation is a recognized oncogenic driver and is a molecular genetic abnormality indicating the presence of a splice site mutation that results in a loss of transcription of exon 14 of the MET gene. Most exon 14 mutations occur in never-smokers and is seen in both squamous and adenocarcinoma histology. Patients whose cancers have MET exon 14 skipping generally have very high response rates to MET inhibitors and molecular testing for MET exon 14 skipping should therefore be performed on all lung cancers, because this is a targetable alteration. MET amplification has been more commonly seen in smokers, and responses in patients with MET-amplified tumors might be more variable and dependent on level of amplification, with higher responses noted in tumors with more than 5-6 fold amplification. Tumors with MET exon 14 skipping mutations usually do not harbor activating mutations in EGFR, KRAS, or BRAF or concurrent ALK, ROS1 or RET translocations. However, it appears that cMET exon 14 skipping is not mutually exclusive with cMET amplification.

TABRECTA® (Capmatinib) is a highly potent and selective, reversible inhibitor of MET tyrosine kinase. The present FDA approval was based on the primary findings from the Phase II GEOMETRY mono-1 trial, which is a non-randomized, open-label, multi-cohort, Phase II study, conducted to evaluate the efficacy and safety of single-agent TABRECTA® in adult patients with EGFR wild-type, ALK-negative, metastatic NSCLC, whose tumors have a mutation that leads to MET exon 14 skipping (METex14), as detected by an RNA-based RT-PCR. This study enrolled 97 patients with metastatic NSCLC and confirmed MET exon 14 skipping mutations, 69 of whom were previously treated and, 28 of whom, were treatment naive. The patients received TABRECTA® at 400 mg orally twice daily until disease progression or unacceptable toxicity. The median patient age was 71 years and all NSCLC histologies including sarcomatoid/carcinosarcoma were included. Majority of the patients (75%) were white and 24% were Asian. Previous treatments included immunotherapy (28%) and chemotherapy (94%), and 23% of patients received 2 prior lines of therapy. The main efficacy outcome was Overall Response Rate (ORR) and additional efficacy outcomes included Duration of Response, Time to Response, Disease Control Rate, Progression Free Survival (PFS) and Safety. Thirteen patients (N=13) in this study had brain metastases at baseline.

Among the treatment-naïve patients group, the ORR was 68% with a median Duration of Response of 12.6 months and the percentage of patients with responses for 12 months or longer was 47%. The Disease Control Rate (Complete Response plus Partial Response plus Stable Disease) was 96.4%.

Among the previously treated patients, the ORR was 41%, with a median Duration of Response of 9.7 months and the percentage of patients with responses for 12 months or longer was 32%. The Disease Control Rate was 78.3%. Among those with brain metastases at baseline, 54% had an intracranial response with TABRECTA® with 31% showing complete resolution, 23% showing partial resolution, and the intracranial Disease Control Rate was 92%. The most common adverse events (occurring in at least 20% of patients) were peripheral edema, nausea, fatigue, vomiting, dyspnea, and decreased appetite. TABRECTA® can also cause Interstitial Lung Disease, hepatotoxicity and photosensitivity.

It was concluded that TABRECTA® is a new treatment option for patients with MET exon 14 skipping- mutated advanced NSCLC, regardless of the line of therapy, with deep and durable responses, manageable toxicity profile, and is the first and only FDA approved treatment for this patient group.
Capmatinib (INC280) in METex14-mutated advanced non-small cell lung cancer (NSCLC): Efficacy data from the phase II GEOMETRY mono-1 study. Wolf J, Seto T, Han J, et al. J Clin Oncol. 2019;37(suppl; abstr 9004).

FDA Approves TUKYSA® for HER2+ Breast Cancer

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SUMMARY: The FDA on April 17, 2020, approved TUKYSA® (Tucatinib) in combination with Trastuzumab and XELODA® (Capecitabine), for adult patients with advanced unresectable or metastatic HER2-positive breast cancer, including patients with brain metastases, who have received one or more prior anti-HER2-based regimens in the metastatic setting. Breast cancer is the most common cancer among women in the US and about 1 in 8 women (13%) will develop invasive breast cancer during their lifetime. Approximately 276,480 new cases of invasive female breast cancer will be diagnosed in 2020 and about 42,170 women will die of the disease.

The HER or erbB family of receptors consist of HER1, HER2, HER3 and HER4. Approximately 15-20% of invasive breast cancers overexpress HER2/neu oncogene, which is a negative predictor of outcomes without systemic therapy. Patients with HER2-positive metastatic breast cancer are often treated with anti-HER2 targeted therapy along with chemotherapy, irrespective of hormone receptor status, and this has resulted in significantly improved treatment outcomes. HER2-targeted therapies include HERCEPTIN® (Trastuzumab), TYKERB® (Lapatinib), PERJETA® (Pertuzumab) and KADCYLA® (ado-Trastuzumab emtansine). Dual HER2 blockade with HERCEPTIN® and PERJETA®, given along with chemotherapy (with or without endocrine therapy), as first line treatment, in HER2 positive metastatic breast cancer patients, was shown to significantly improve Progression Free Survival (PFS) as well as Overall Survival (OS). The superior benefit with dual HER2 blockade has been attributed to differing mechanisms of action and synergistic interaction between HER2 targeted therapies. Patients progressing on Dual HER2 blockade often receive KADCYLA® which results in an Objective Response Rate (ORR) of 44% and a median PFS of 9.6 months, when administered after HERCEPTIN® and a taxane. There is however no standard treatment option for this patient population following progression on KADCYLA®.

It is estimated that close to 50% of patients with HER2-positive metastatic breast cancer develop brain metastases. Systemic HER2-targeted agents, including Tyrosine Kinase Inhibitors, as well as chemotherapy have limited antitumor activity in the brain. Local therapeutic interventions for brain metastases include neurosurgical resection and Stereotactic or Whole-Brain Radiation Therapy.

TUKYSA® (Tucatinib) is an oral Tyrosine Kinase Inhibitor that is highly selective for the kinase domain of HER2 with minimal inhibition of Epidermal Growth Factor Receptor. In a Phase 1b dose-escalation trial, TUKYSA® in combination with HERCEPTIN® and XELODA® (Capecitabine) showed encouraging antitumor activity in patients with HER2-positive metastatic breast cancer, including those with brain metastases.

HER2CLIMB is an international, randomized, double-blind trial in which the combination of TUKYSA® plus HERCEPTIN® and XELODA® was compared with placebo plus HERCEPTIN® and XELODA®. A total of 612 patients with unresectable locally advanced or metastatic HER2-positive breast cancer, who were previously treated with HERCEPTIN®, PERJETA® (Pertuzumab) and KADCYLA® (ado-Trastuzumab emtansine) were enrolled. Patients were randomly assigned in a 2:1 ratio to receive either TUKYSA® 300 mg orally twice daily throughout the treatment period (N=410) or placebo orally twice daily (N=201), in combination with HERCEPTIN® 6 mg/kg IV once every 21 days, following an initial loading dose of 8 mg/kg, and XELODA® 1000 mg/m2 orally twice daily on days 1 to 14 of each 21-day cycle. Stratification factors included presence or absence of brain metastases, ECOG Performance Status and geographic region. The median patient age was 54 years and patient demographic as well as disease characteristics at baseline were well balanced between the two treatment groups. In the total treatment population, 47.5% had brain metastases at baseline, 48.3% in the TUKYSA® combination group and 46% in the placebo combination group. The median duration of follow up in the total treatment population was 14 months. The Primary endpoint was Progression Free Survival (PFS) among the first 480 patients who underwent randomization. Secondary end points assessed in the total treatment population (612 patients) included, Overall Survival (OS), PFS among patients with brain metastases, confirmed Objective Response Rate (ORR), and safety.

The Primary endpoint of PFS at 1 year was 33.1% in the TUKYSA®-combination group and 12.3% in the placebo-combination group (HR for disease progression or death=0.54; P<0.001), and the median duration of PFS was 7.8 months and 5.6 months, respectively. This represented a 46% reduction in the risk of cancer progression or death in the TUKYSA®-combination group compared to patients who received HERCEPTIN® and XELODA® alone. The Overall Survival at 2 years was 44.9% in the TUKYSA®-combination group and 26.6% in the placebo-combination group (HR for death=0.66; P=0.005), and the median Overall Survival was 21.9 months and 17.4 months, respectively. This represented a 44% reduction in the risk of death in the TUKYSA®-combination group compared to the placebo-combination group. Among the patients with brain metastases, PFS at 1 year was 24.9% in the TUKYSA®-combination group and 0% in the placebo-combination group (HR=0.48; P<0.001), and the median PFS was 7.6 months and 5.4 months, respectively. This represented a 52% reduction in the risk of cancer progression or death in the TUKYSA®-combination group compared to the placebo-combination group. Among the patients with measurable disease at baseline, the confirmed Objective Response Rate was 40.6% in the TUKYSA®-combination group and 22.8% in the placebo-combination group (P<0.001). Common adverse events in the TUKYSA® group included diarrhea, Palmar-Plantar Erythrodysesthesia syndrome, nausea, vomiting and fatigue. Diarrhea and abnormal liver function tests were more common in the TUKYSA®-combination group than in the placebo-combination group.

It was concluded that in heavily pretreated patients with HER2-positive metastatic breast cancer, including those with brain metastases, the addition of TUKYSA® to HERCEPTIN® and XELODA® resulted in clinically significant improvement in PFS and OS, compared to the placebo-combination group. This trial is unique in that it included patients with active brain metastases, either untreated or progressing.

Tucatinib, Trastuzumab, and Capecitabine for HER2-Positive Metastatic Breast Cancer. Murthy RK, Loi S, Okines A, et al. N Engl J Med 2020;382:597-609.

FDA Approves PEMAZYRE®, First Targeted Therapy for Cholangiocarcinoma

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SUMMARY: The FDA on April 17, 2020 granted accelerated approval to PEMAZYRE® (Pemigatinib), for the treatment of adults with previously treated, unresectable locally advanced or metastatic Cholangiocarcinoma with a Fibroblast Growth Factor Receptor 2 (FGFR2) fusion or other rearrangement, as detected by an FDA-approved test. The FDA also approved the FoundationOne® CDX (Foundation Medicine, Inc.), as a companion diagnostic for patient selection.

Bile Duct cancer (Cholangiocarcinoma), comprise about 30% of all primary liver tumors and includes both intrahepatic and extrahepatic bile duct cancers. Klatskin tumor is a type of Cholangiocarcinoma that begins in the hilum, at the junction of the left and right bile ducts. It is the most common type of Cholangiocarcinoma, accounting for more than half of all cases. About 8,000 people in the US are diagnosed with Cholangiocarcinoma each year and approximately 20% of the cases are suitable for surgical resection, whereas a majority of patients at diagnosis have advanced disease. The 5-year survival is less than 10%, with limited progress made over the past two decades. There is therefore an unmet need for new effective therapies.

FGFRs (Fibroblast Growth Factor Receptors) play an important role in tumor cell proliferation and survival, migration and angiogenesis. Activating fusions, rearrangements, translocations and gene amplifications in FGFRs result in dysregulation of FGFR signaling, and may contribute to the pathogenesis of various cancers, including Cholangiocarcinoma. FGFR2 fusions or rearrangements occur almost exclusively in intrahepatic Cholangiocarcinoma, where they are observed in 10-16% of patients. PEMAZYRE® is a potent, selective, oral kinase inhibitor of FGFR isoforms 1, 2 and 3, which in preclinical studies has demonstrated selective pharmacologic activity against cancer cells with FGFR alterations.FGFR-Signaling-Pathway

The FIGHT-202 ((FIbroblast Growth factor receptor in oncology and Hematology Trials) is a Phase II, multi-center, open-label, single-arm study which evaluated the safety and efficacy of PEMAZYRE® (Pemigatinib) in adult patients with previously treated, locally advanced or metastatic Cholangiocarcinoma with documented FGFR2 fusion or rearrangement. Patients were enrolled into one of three cohorts: Cohort A with FGFR2 fusions or rearrangements (N=107), Cohort B with other FGF/FGFR genetic alterations (N=20) or Cohort C with no FGF/FGFR genetic alterations (N=18). All patients received PEMAZYRE® 13.5 mg orally once daily, two weeks on and one week off, on a 21-day cycle, until radiological disease progression or unacceptable toxicity. The median patient age of the entire enrolled patient group was 59 years and patients were scanned every eight weeks to assess response to PEMAZYRE®. The Primary endpoint of FIGHT-202 was Objective Response Rate (ORR) in Cohort A, assessed by Independent Review per RECIST criteria. Secondary endpoints included ORR in Cohorts B, A plus B, and C, Duration of Response (DOR), Disease Control Rate (DCR), Progression Free Survival (PFS), Overall Survival (OS), and safety.

It was noted that PEMAZYRE® monotherapy resulted in an Objective Response Rate of 36%, with Complete Response Rate of 2.8% and a Partial Response Rate of 33%. Among those who had a response, 63% had a response lasting 6 months or longer and 18% had a response lasting 12 months or longer. The median Duration of Response was 7.5 months and the Disease Control Rate (DCR) was 82%. The median PFS and median OS were 6.9 months and 21.1 months, and the OS data was not mature at the time of data cutoff. In Cohorts B and C, none of the patients achieved a response. The most common Adverse Events were hyperphosphatemia, alopecia, diarrhea, fatigue, nail toxicities and dysgeusia. Hyperphosphatemia was managed with diet modifications, phosphate binders, diuretics or dose modifications. Fewer patients discontinued therapy in Cohort A compared to Cohort B and C.

It was concluded that based on Overall Response Rate and Duration of Response, PEMAZYRE® is the first and only FDA-approved treatment for previously treated patients with Cholangiocarcinoma, harboring FGFR2 gene rearrangements or fusions.

Pemigatinib for previously treated, locally advanced or metastatic cholangiocarcinoma: a multicentre, open-label, phase 2 study. Abou-Alfa GK, Sahai V, Hollebecque A, et al. Lancet Oncol. 2020 Mar 20. pii: S1470-2045(20)30109-1. doi: 10.1016/S1470-2045(20)30109-1. [Epub ahead of print]

FDA Approves BRAFTOVI® in Combination with ERBITUX® for Metastatic Colorectal Cancer

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SUMMARY: The FDA on April 8, 2020, approved BRAFTOVI® (Encorafenib) in combination with ERBITUX® (Cetuximab) for the treatment of adult patients with metastatic ColoRectal Cancer (CRC) with a BRAF V600E mutation, detected by an FDA-approved test, after prior therapy. Colorectal Cancer is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 147,950 new cases of CRC will be diagnosed in the United States in 2020 and about 53,200 patients are expected to die of the disease. The lifetime risk of developing CRC is about 1 in 23.

Advanced colon cancer is often incurable and standard chemotherapy when combined with anti EGFR (Epidermal Growth Factor Receptor) targeted monoclonal antibodies such as VECTIBIX® (Panitumumab) and ERBITUX® (Cetuximab) as well as anti VEGF agent AVASTIN® (Bevacizumab), have demonstrated improvement in Progression Free Survival (PFS) and Overall Survival (OS). The benefit with anti EGFR agents however is only demonstrable in patients with metastatic CRC (mCRC), whose tumors do not harbor KRAS mutations in codons 12 and 13 of exon 2 (KRAS Wild Type). It is now also clear that even among the KRAS Wild Type patient group about 15-20% have other rare mutations such as NRAS and BRAF mutations, which confer resistance to anti EGFR agents. Patients with stage IV colorectal cancer are now routinely analyzed for extended RAS and BRAF mutations. KRAS mutations are predictive of resistance to EGFR targeted therapy. Approximately 8-15% of all metastatic CRC tumors present with BRAF V600E mutations and BRAF V600E is recognized as a marker of poor prognosis in this patient group. These patients tend to have aggressive disease with a higher rate of peritoneal metastasis and do not respond well to standard treatment intervention. Approximately 20% of the BRAF-mutated population in the metastatic setting has MSI-High tumors, but MSI-High status does not confer protection to this patient group.BRAF-and-MEK-Inhibition-in-MAPK-Pathway

The Mitogen-Activated Protein Kinase pathway (MAPK pathway) is an important signaling pathway which enables the cell to respond to external stimuli. This pathway plays a dual role, regulating cytokine production and participating in cytokine dependent signaling cascade. The MAPK pathway of interest is the RAS-RAF-MEK-ERK pathway. The RAF family of kinases includes ARAF, BRAF and CRAF signaling molecules. BRAF is a very important intermediary of the RAS-RAF-MEK-ERK pathway. The BRAF V600E mutations results in constitutive activation of the MAP kinase pathway. Inhibiting BRAF can transiently reduce MAP kinase signaling. However, this can result in feedback upregulation of EGFR signaling pathway, which can then reactivate the MAP kinase pathway. This aberrant signaling can be blocked by dual inhibition of both BRAF and EGFR. It should be noted that BRAF V600E-mutated CRC is inherently less sensitive to BRAF inhibition than Malignant Melanoma.

BRAFTOVI® (Encorafenib) is a BRAF inhibitor and has target binding characteristics that differ from other BRAF inhibitors such as ZELBORAF® (Vemurafenib) and TAFINLAR® (Dabrafenib), with a prolonged target dissociation half-life and higher potency. The combination of BRAFTOVI® along with anti-EGFR monoclonal antibody ERBITUX® (Cetuximab) showed promising activity in early-phase clinical trials.

The present FDA approval was based on BEACON CRC (Binimetinib, Encorafenib, and Cetuximab Combined to Treat BRAF-Mutant Colorectal Cancer) trial, which is an international, multicenter, randomized, open-label, Phase III study in which the efficacy and safety of BRAFTOVI® plus ERBITUX® with or without a MEK inhibitor MEKTOVI® (Binimetinib), was compared with the investigators’ choice of ERBITUX® combined with either Irinotecan or Fluorouracil, Folinic acid, and Irinotecan, in patients with BRAF V600E-mutant mCRC, whose disease has progressed after one or two prior regimens. Eligible patients were required to have BRAF V600E mutation-positive metastatic CRC (detected by the Qiagen therascreen® BRAF V600E RGQ PCR kit), with disease progression after one or two prior regimens. In this trial, 665 patients were randomly assigned in a 1:1:1 ratio to receive either triplet therapy of BRAFTOVI® 300 mg orally daily, MEKTOVI® 45 mg orally twice daily, and ERBITUX® 400 mg/m2 IV as an initial dose, then 250 mg/m2 IV weekly (N=224), doublet-therapy of BRAFTOVI® and ERBITUX® administered in the same doses and on the same schedule as the triplet regimen (N=220) or investigators’ choice of ERBITUX® combined with either Irinotecan or Fluorouracil, Folinic acid, and Irinotecan (N=221). Patients were stratified according to previous Irinotecan use and treatment was administered in 28-day cycles until disease progression. The co-Primary end points were Overall Survival (OS) in the triplet-therapy group as compared with the control group and Secondary end points included OS in the doublet-therapy group as compared with the control group, as well as Progression Free Survival, Duration of Response, and Safety in all groups. This study was not powered to compare the triplet-therapy group against the doublet-therapy group. The Overall Response Rate (ORR) and Duration of Response were assessed by blinded Independent Central Review in the subset of the first 220 patients assigned to receive either BRAFTOVI® and ERBITUX® or the control group.

The median OS was 8.4 months in the BRAFTOVI® plus ERBITUX® group, compared to 5.4 months in the control group (HR=0.60; P=0.0003), and this represented 40% reduction in the risk of death among the BRAFTOVI® plus ERBITUX® group. Median PFS was 4.2 months in the BRAFTOVI® plus ERBITUX® group compared to 1.5 months in the control group (HR=0.40; P< 0.0001). The ORR was 20% and 2% respectively. The median Duration of Response was 6.1 months for the BRAFTOVI® plus ERBITUX® group and Not Reached in the control arm. The median OS was 9.0 months in the triplet-therapy group and 5.4 months in the control group (HR for death=0.52; P<0.001). This represented 48% reduction in the risk of death in the triplet-therapy group. Both the triplet and doublet regimens reduced the risk of Quality of Life (QoL) deterioration by about 45% by different QoL assessment instruments, compared with the control regimen. The most common adverse reactions in the BRAFTOVI® plus ERBITUX® group were fatigue, nausea, diarrhea, dermatitis acneiform, abdominal pain, decreased appetite, arthralgia, and rash.

It was concluded from the BEACON CRC trial that a combination of BRAFTOVI®, MEKTOVI® and ERBITUX® as well as a combination of BRAFTOVI® plus ERBITUX® resulted in significantly longer Overall Survival and a higher Response Rate than standard therapy, in patients with metastatic Colorectal Cancer, with the BRAF V600E mutation.
Encorafenib, Binimetinib, and Cetuximab in BRAF V600E-Mutated Colorectal Cancer. Kopetz S, Grothey A, Yaeger R, et al. N Engl J Med 2019; 381:1632-1643

Blood-Based Screening Test Identifies Gastrointestinal Cancers

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SUMMARY: It is estimated that cancers of the esophagus, stomach, pancreas, gallbladder, liver, bile duct, colon and rectum account for approximately 17% of incident cancer diagnoses and 26% of cancer-related deaths in the US. There are currently no screening tests available for cancers of the gallbladder, bile duct, and pancreatic cancer. Although screening tests do exist for other types of GI malignancies such as colorectal and stomach cancer, many of them are invasive. Further, when GI malignancies are diagnosed, they are frequently at advanced stages and are more difficult to treat.
A noninvasive, liquid biopsy assay based on circulating tumor DNA (ctDNA) has the potential to detect cancer in early stages among asymptomatic individuals. ctDNA refers to DNA fragments that are shed into the bloodstream by cancer cells after apoptosis or necrosis. ctDNA can detect almost all molecular alterations present in cancer cells and genotyping circulating cell-free tumor DNA (cfDNA) in the plasma can potentially overcome the shortcomings of repeat biopsies and tissue genotyping, allowing the detection of many more targetable gene mutations, thus resulting in better evaluation of the tumor genome landscape. The proportion of cfDNA that originates from a tumor depends on the anatomic location, tumor burden and cell turnover. cfDNA also allows real-time monitoring for treatment response and resistance.
The Cancer Genome Atlas (TCGA), a landmark cancer genomics program, is a joint effort between the National Cancer Institute and the National Human Genome Research Institute. This program began in 2006 and has molecularly characterized over 20,000 primary cancers and matched normal samples, across 33 different cancer types. After 12 years and contributions from over 11,000 patients, TCGA has deepened our understanding of the molecular basis of cancer, changed the way cancer patients are managed in the clinic, established a rich genomics data resource for the research community, and helped advance health and science technologies.
The Circulating Cell-Free Genome Atlas (CCGA) is a prospective, multi-center, case-control, observational study with longitudinal follow up, and is the largest study ever initiated, to develop a noninvasive, liquid biopsy assay for early cancer detection based on cell-free DNA (cfDNA). This study completed enrollment of approximately 15,000 participants with and without cancer (56% with more than 20 tumor types and all clinical stages), across 142 sites in the US and Canada. The purpose of this study is to collect biological samples from patients with a new diagnosis of cancer (blood and tumor tissue) and from individuals who do not have a diagnosis of cancer (blood), in order to characterize the population heterogeneity in cancer and non-cancer participants, and to develop models for distinguishing cancer from non-cancer. The principal goal is to develop a noninvasive cancer detection assay and the CCGA was designed to characterize the landscape of genomic cancer signals in the blood and to detect and validate GRAIL, Inc.’s multi-cancer early detection blood test through three pre-planned sub-studies. 
GRAIL, Inc., is a healthcare company focused on the early detection of cancer by using the power of Next-Generation Sequencing, population-scale clinical studies, and state-of-the-art computer science and data science to enhance the scientific understanding of cancer biology, and to develop its multi-cancer early detection blood test. GRAIL’s high efficiency methylation technology preferentially targets the most informative regions of the genome, and is designed to use its proprietary database and machine-learning algorithms to both detect the presence of cancer and identify the tumor’s Tissue of Origin. GRAIL’s sequencing database of cancer and non-cancer methylation signatures is believed to be the largest of its kind, and covers approximately 30 million methylation sites across the genome, with more than 20 cancer types across stages represented within the database.
Previously reported data from the first sub-study of CCGA showed GRAIL’s prototype technology could detect the presence of multiple deadly cancer types with a low rate of false positive results (high specificity). In this analysis blood samples from 166 participants who had a cancer diagnosis at the time of enrollment were evaluated, and cancer was detected using the methylation technology. Results showed that GRAIL’s prototype technology correctly identified the tumor’s Tissue of Origin in 87% of the blood samples evaluated (N=144/166), including 96% of breast cancer cases (N=22/23), 88% of lung cancer cases (N=29/33), 90% of liver cancer cases (N=9/10) and 100% of pancreatic cancer cases (N=17/17).
GRAIL has since selected methylation as its preferred approach and evaluated its refined methylation blood test in the second pre-planned sub-study of CCGA. It was determined that whole-genome bisulfite sequencing for DNA methylation was the most effective approach for early cancer detection. DNA methylation is a natural epigenetic mechanism used by cells to regulate gene expression with some regions of hypermethylation and some regions of hypomethylation, and is a chemical modification to DNA, that can change how a gene’s function is carried out by the body without changing the order of the DNA bases. In cancer, abnormal methylation patterns and the resulting changes in gene expression can contribute to tumor growth (hypermethylation can cause tumor-suppressor genes to be inactivated). Methylation patterns or signatures, are unique to the tumor DNA, enabling tumor detection and localization, but are not of value when it comes to precision therapies. This is unlike mutations and copy number changes, which can be detected in white blood cells in individuals without cancer as well, leading to false-positives.
The researches in this second substudy reported the performance of methylation-based cfDNA early multi-cancer detection test, for GastroIntestinal (GI) tract cancers, and also provided data from individuals without known cancer (non-cancer controls). To test the current assay, the second substudy included approximately 4,500 individuals, both with and without cancer, who were split into a training cohort and a validation cohort. Of the 2,185 patients with newly-diagnosed cancer in the second substudy, 447 patients were diagnosed with GI malignancies. Plasma cfDNA was subjected to targeted methylation analysis to develop an algorithm that could identify the presence or absence of cancer, as well as the Tissue of Origin of the cancer. The GI malignancies included Esophagus/Stomach (N=67), Pancreas/Gallbladder/Extrahepatic bile duct (N=95), Liver/Intrahepatic bile duct (N=29), and Colon/Rectum (N=121). To minimize the likelihood of false-positives, the targeted methylation assay was pre-set to yield greater than 99% specificity.
The test showed a sensitivity level of approximately 82% for detecting GI cancers of all stages in the independent validation set. The predicted Tissue of Origin accuracy across all GI cancers was 92%.
It was concluded that this assay performed using a single noninvasive blood sample, has the potential to diagnose a variety of gastrointestinal cancers earlier, when they are more treatable, with good sensitivity and with a low rate of false positives. Performance of a blood-based test for the detection of multiple cancer types. Wolpin BM, Richards DA, Cohn AL, et al. J Clin Oncol. 2020;38(suppl 4; abstr 283).

Biomarkers May Predict Response to BRAF and MEK inhibitors in Malignant Melanoma

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Biomarkers May Predict Response to BRAF and MEK inhibitors in Malignant Melanoma 
SUMMARY: It is estimated that in the US, approximately 100,350 new cases of malignant melanoma will be diagnosed in 2020 and about 6850 patients are expected to die of the disease. The incidence of melanoma has been on the rise for the past three decades. Surgical resection with a curative intent is the standard of care for patients with early stage melanoma, with a 5-year survival rate of 98% for Stage I disease and 90% for Stage II disease. Patients with locally advanced or metastatic melanoma historically have had poor outcomes. With the development and availability of immune checkpoint inhibitors and BRAF and MEK inhibitors, this patient group now has significantly improved outcomes. In treatment naïve patients receiving anti-PD-1 therapies such as KEYTRUDA® (Pembrolizumab) or OPDIVO® (Nivolumab) in Phase III trials, the Progression Free Survival (PFS) rates have ranged from 27-31%, with an Overall Survival (OS) rate of 46% at 4 years. The 5-year OS among patients receiving KEYTRUDA® was 43%, and in those treated with a combination of OPDIVO® plus YERVOY® (Ipilimumab), 4-year PFS and OS rates were 37% and 53%, respectively.BRAF-MEK-Inhibition-in-MAPK-Pathway
The Mitogen-Activated Protein Kinase pathway (MAPK pathway) is an important signaling pathway which enables the cell to respond to external stimuli. This pathway plays a dual role, regulating cytokine production and participating in cytokine dependent signaling cascade. The MAPK pathway of interest is the RAS-RAF-MEK-ERK pathway. The RAF family of kinases includes ARAF, BRAF and CRAF signaling molecules. BRAF is a very important intermediary of the RAS-RAF-MEK-ERK pathway. BRAF mutations have been detected in 6-8% of all malignancies. The most common BRAF mutation in melanoma is at the V600E/K site and is detected in approximately 50% of melanomas, and result in constitutive activation of the MAPK pathway.
TAFINLAR® (Dabrafenib), is a selective oral BRAF inhibitor and MEKINIST® (Trametinib) is a potent and selective inhibitor of MEK gene, which is downstream from RAF in the MAPK pathway. Long term survival data pooled from two randomized Phase III COMBI-d and COMBI-v trials, which involved previously untreated, unresectable or metastatic melanoma patients, with BRAFV600E or V600K mutation who had received TAFINLAR® along with MEKINIST® showed PFS rates of 21% at 4 years and 19% at 5 years. The OS rates were 37% at 4 years and 34% at 5 years. The 5-year OS rate was 71% among patients who had a Complete Response and 55% among those who had a normal LDH level plus fewer than three metastatic organ sites at baseline.
With the approval of multiple therapeutic options for the management of patients with BRAF-mutant melanoma, treatment decisions have become increasingly complex. In patients with limited disease burden, immunotherapy with checkpoint inhibitors is favored by most clinicians based on the long term data supporting the durability of responses with immunotherapies. On the contrary, BRAF-targeted agents are utilized in patients with extensive, symptomatic disease and active brain metastases. The optimal sequence of these therapeutic strategies in order to improve long-term patient outcome, has remained unclear. 
COMBI-AD is an international, multi-center, randomized, double-blind, placebo-controlled, Phase III trial, in which 870 patients with completely resected, Stage III melanoma and with BRAF V600E or V600K mutations were enrolled. Patients were randomly assigned in a 1:1 to receive TAFINLAR® 150 mg orally twice daily in combination with MEKINIST® 2 mg orally once daily (N=438) or two matched placebos (N=432). Treatment was given for 12 months. At a median follow up of 2.8 years, the estimated 3-year Relapse Free Survival (RFS) rate was 58% with a combination of TAFINLAR® and MEKINIST® and 39% in the placebo group (HR=0.47; P<0.001), and this represented a 53% lower risk of relapse. The risk of distant metastases or death was reduced by 49% with the combination therapy versus placebo (HR=0.51; P<0.001). A prespecified exploratory outcome of this trial was assessment of biomarkers. The authors assessed intrinsic tumor genomic features in 368 patients using Next-Generation DNA sequencing, and tumor microenvironment characteristics were assessed in 507 patients by use of a NanoString RNA assay, in an attempt to provide prognostic and predictive information. Median follow up at data cutoff was 44 months in the TAFINLAR® plus MEKINIST® group and 42 months in the placebo group.
Baseline MAPK pathway genomic alterations did not affect treatment benefit or outcomes in either treatment groups. An Interferon Gamma gene expression signature higher than the median was prognostic for prolonged RFS in both treatment groups. Tumor Mutational Burden (TMB) was independently associated with better RFS in the placebo group (HR for top third versus bottom third of TMB values=0.56; P=0.0056), but this benefit was not seen in the TAFINLAR® plus MEKINIST® group (HR= 0.83; P=0.44). However, patients with TMB in the lower two terciles who received TAFINLAR® plus MEKINIST® combination had improved RFS compared to those who received placebo (HR=0.49: P<0.0001). Patients with high TMB appeared to have a less pronounced benefit with TAFINLAR® plus MEKINIST® targeted therapy, compared to placebo, especially if they had an Interferon Gamma gene expression signature lower than the median. 
It was concluded from this biomarker analysis that high Tumor Mutational Burden was independently associated with better Relapse Free Survival in the placebo group but not in the TAFINLAR® plus MEKINIST® combination group, and an Interferon Gamma gene expression signature higher than the median was prognostic for prolonged RFS in both treatment groups. Adjuvant dabrafenib plus trametinib versus placebo in patients with resected, BRAFV600-mutant, stage III melanoma (COMBI-AD): exploratory biomarker analyses from a randomised, phase 3 trial. Dummer R, Brase JC, Garrett J, et al. The Lancet Oncology. Published:January 30, 2020DOI:https://doi.org/10.1016/S1470-2045(20)30062-0

Multigene Testing for All Patients with Breast Cancer Could Identify Many More Mutation Carriers

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SUMMARY: Breast cancer is the most common cancer among women in the US and about 1 in 8 women (12%) will develop invasive breast cancer during their lifetime. Approximately 279,100 new cases of invasive breast cancer will be diagnosed in 2020 and about 42,690 individuals will die of the disease. DNA can be damaged due to errors during its replication or as a result of environmental exposure to ultraviolet radiation from the sun or other toxins. The tumor suppressor genes such as BRCA1 (Breast Cancer 1) and BRCA2 help repair damaged DNA and thus play an important role in maintaining cellular genetic integrity, failing which these genetic aberrations can result in malignancies. The BRCA1 gene is located on the long (q) arm of chromosome 17 whereas BRCA2 is located on the long arm of chromosome 13. These mutations can be inherited from either of the parents in an Autosomal Dominant pattern and a child has a 50% chance of inheriting this mutation, and the deleterious effects of the mutations are seen even when an individual’s second copy of the gene is normal.
It is estimated that BRCA1/2 gene mutations occur in approximately 1 in 400 women in the general population and account for 20-25% of hereditary breast cancers, about 5-10% of all breast cancers and 15% of ovarian cancers. Mutations in the BRCA1/2 genes increase breast cancer risk 45-65% by age 70 years. The risk of ovarian, fallopian tube, or peritoneal cancer, increases to 39% for BRCA1 mutations, and 10-17% for BRCA2 mutations. PALB2 (Partner And Localizer of BRCA2) gene provides instructions to make a protein that works along with the BRCA2 protein, to repair damaged DNA. PALB2 mutation is rare in sporadic breast cancer, and is considered a high-penetrance breast cancer predisposing gene associated with 14% risk of developing breast cancer by age 50 and a 35% risk of developing breast cancer by age 70. Women with a PALB2 mutation face an increased risk of triple negative breast cancer and higher risk of death from breast cancer. PALB2 gene mutations have also been implicated in ovarian, pancreatic and other malignancies.
Current guidelines recommend genetic testing in women with breast cancer who fulfill recognized or established family history or clinical criteria. However, patients with breast cancer and genetic pathogenic variants do not always have a positive family history, and these criteria miss approximately 50% of pathogenic variant carriers. Further, genetic testing based on family history or clinical criteria depends on the awareness and understanding both by the health care providers and patients, and appropriate referrals to genetic counselors. Because of limited awareness and restricted access to genetic testing and counseling services, only 20-30% of eligible patients undergo genetic testing, and 97% of estimated carriers in the general population remain unidentified, thereby missing substantial opportunities for primary prevention. 
Knowledge of a patient’s genetic pathogenic variant status has important therapeutic and prognostic implications. Identifying unaffected relatives carrying pathogenic variants enables early diagnosis and cancer prevention by offering risk management options such as enhanced MRI imaging and mammography screening, risk-reducing surgeries such as prophylactic mastectomy, salpingo-oopherectomy and chemoprevention with Selective Estrogen Receptor Modulators.
The authors in this study estimated the downstream health effects, costs and cost-effectiveness of multigene testing for all patients with breast cancer, compared with current practice of BRCA testing based on clinical criteria or family history alone. In this modeling study, data was incorporated from four large breast cancer clinical trials and/or research cohorts in the United States, United Kingdom, and Australia. This analysis included 11,836 women with invasive breast cancer, regardless of the family history, and compared lifetime costs and effects of high-risk BRCA1/BRCA2/PALB2 (multigene) testing of all unselected patients with breast cancer (Strategy A) with BRCA1/BRCA2 testing based on family history or clinical criteria (Strategy B), in UK and US populations, from January 1, 2018, through June 8, 2019.
Affected patients with BRCA/PALB2 mutations could undertake contralateral preventive mastectomy and BRCA carriers could choose Risk-Reducing Salpingo-Oophorectomy (RRSO). If patients had a BRCA1/BRCA2/PALB2 pathogenic variant, their first-degree relatives undergo testing for the familial pathogenic variant. If the first-degree relative had a BRCA1/BRCA2/PALB2 pathogenic variant, second-degree relatives undergo testing. Unaffected relative carriers could undergo MRI or mammography screening, chemoprevention, or risk-reducing mastectomy for breast cancer risk and RRSO for ovarian cancer risk. This analysis incorporated lifetime risks and long-term consequences to provide a lifetime horizon. Incidence of ovarian cancer, breast cancer, excess deaths due to heart disease, and the overall population effects were estimated.
Multigene testing was restricted to BRCA1/BRCA2/PALB2, to comply with the ACCE framework for genetic testing, which was advocated for clinical applicability of genetic testing. The ACCE framework includes Analytic validity which is technical test performance, Clinical validity which is the ability of a genetic test to identify or predict accurately and reliably the clinically defined disorder or phenotype of interest, Clinical utility which is evidence that a genetic test improves clinical outcomes measurably and that it adds value for patient management decision making compared with current management without genetic testing, and ELSI which are the complex Ethical, Legal, and Social Implications associated with genetic tests.
This study showed that unselected BRCA1/BRCA2/PALB2 testing for all patients at breast cancer diagnosis was extremely cost-effective compared with BRCA1/BRCA2 testing based on clinical criteria or family history for both UK and US health systems, with incremental cost-effectiveness ratios of £10,464 or £7,216 and $65,661 or $61,618 per Quality-Adjusted Life-Year, respectively. Quality-Adjusted Life-Year (QALY) is a measurement of health outcomes in economic evaluations recommended by NICE (National Institute of Health and Clinical Excellence). This is well below UK and US cost-effectiveness thresholds. The authors estimated that one year’s unselected panel genetic testing could prevent 1142 cases of breast cancer, 959 cases of ovarian cancer, and 633 deaths related to breast or ovarian cancer in the UK. In the US, one year’s unselected panel genetic testing could prevent 5478 cases of breast cancer, 4255 cases of ovarian cancer, and 2406 deaths related to breast or ovarian cancer. 
It was concluded from this analysis that unselected, high-risk multigene testing for all women with breast cancer is extremely cost-effective, compared with testing based on family history or clinical criteria, and could identify many more mutation carriers who can benefit from precision prevention. The authors added that these findings support changing current policy to expand genetic testing to all women with breast cancer. A Cost-effectiveness Analysis of Multigene Testing for All Patients with Breast Cancer. Sun L, Brentnall A, Patel S, et al. JAMA Oncol. 2019;5:1718-1730

Circulating Tumor DNA in the Peripheral Blood Predicts Recurrence Risk After Surgery and Adjuvant Chemotherapy in Stage III Colon Cancer

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SUMMARY: ColoRectal Cancer (CRC) is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 145,600 new cases of CRC were diagnosed in the United States in 2019 and about 51,020 patients died of the disease. The lifetime risk of developing CRC is about 1 in 23. Adjuvant chemotherapy for patients with resected, locally advanced, node-positive (Stage III) colon cancer has been the standard of care since the 1990s. Adjuvant treatment with an ELOXATIN® (Oxaliplatin) based chemotherapy regimen has been considered standard intervention since 2004, for patients with Stage III colon cancer, following surgical resection, and has been proven to decrease the chance of recurrent disease. Chemotherapy regimens have included (FOLFOX – Leucovorin, 5-FluoroUracil, ELOXATIN®) or CAPOX/XELOX (XELODA®/Capecitabine and ELOXATIN®), given over a period of 6 months. In spite of these advancements, defining patient subsets at high risk of recurrence following standard adjuvant therapy remains challenging and treatment failure can only be acknowledged when clinical recurrence is documented.
Cell-free DNA (cfDNA) refers to DNA molecules that circulate in the bloodstream after cell apoptosis or necrosis. A specific portion of cfDNA that originates from tumor cells is referred to as circulating tumor DNA (ctDNA), which can be detected in the cell-free component of peripheral blood samples in almost all patients with advanced solid tumors including advanced colorectal cancer. ctDNA is a valuable biomarker and allows early detection of relapse. Several studies have shown that detectable ctDNA following surgery for early stage cancers, is associated with a very high risk of recurrence. The authors in this publication report on the results of a correlative biomarker study in patients with Stage III colon cancer, undergoing standard adjuvant chemotherapy.
A multicenter, population-based, cohort study was conducted to determine whether serial post-surgical and post-chemotherapy ctDNA analysis could provide a real-time indication of efficacy of adjuvant therapy in Stage III colon cancer. In this study, 100 patients with newly diagnosed Stage III colon cancer who were planned to receive 24 weeks of adjuvant chemotherapy were enrolled. Patients had R0 resection with no evidence of metastatic disease on staging CT of the chest, abdomen, and pelvis before surgery. The chemotherapy regimen was chosen by the treating physician, who was blinded to the ctDNA result. High-risk patients were defined as those having pT4 and/or pN2 disease according to the pTNM staging system. Blood samples for ctDNA and CEA (CarcinoEmbryonic Antigen) analysis were collected 4-10 weeks after surgery prior to commencement of adjuvant chemotherapy and at the completion of adjuvant therapy, within 6 weeks of the final cycle of chemotherapy. All patients had a surveillance CT scan 4-8 weeks after completion of adjuvant chemotherapy. Follow up surveillance included clinical exam every 3 months along with CEA measurement and annual CT imaging for 3 years. Serial plasma samples were collected after surgery and after chemotherapy. Somatic mutations in individual patient tumors were identified by massively parallel sequencing of 15 genes commonly mutated in colorectal cancer, and personalized assays were designed to quantify ctDNA. For each patient, one mutation identified in the tumor tissue was assessed in the plasma for the presence of ctDNA. The median duration of follow up was 28.9 months and the primary aim of this study was to demonstrate the association between postsurgical and post-chemotherapy ctDNA detection and the risk of recurrence.
Among the 96 evaluable patients, circulating tumor DNA was detectable in 20 of 96 (21%) post-surgical samples and these patients had an increased risk of recurrence with associated inferior Recurrence-Free Survival, (HR=3.8; P<0.001). The estimated 3 year Recurrence Free Interval (RFI) for patients with positive ctDNA findings was 47% and for those with ctDNA-negative findings was 76%. Circulating tumor DNA was detectable in 15 of 88 (17%) post-chemotherapy samples. The estimated 3 year RFI was 30% when ctDNA was detectable after chemotherapy and 77% when ctDNA was undetectable (HR=6.8; P<0.001). Postsurgical ctDNA status was an independent predictor of disease recurrence after adjusting for known clinicopathologic risk factors (HR=7.5; P<0.001).
The authors concluded that post-surgical and post-chemotherapy circulating tumor DNA analyses is a promising prognostic marker in Stage III colon cancer, and may identify patients at high risk of recurrence, despite completing standard adjuvant treatment. This high-risk population presents a unique opportunity to explore additional therapeutic approaches. Circulating Tumor DNA Analyses as Markers of Recurrence Risk and Benefit of Adjuvant Therapy for Stage III Colon Cancer. Tie J, Cohen JD, Wang Y, et al. JAMA Oncol. 2019;5:1710-1717.