Author: RR

Maintenance LYNPARZA® Improves Progression Free Survival in BRCA Mutated Metastatic Pancreatic Cancer

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SUMMARY: The American Cancer Society estimates that for 2019, about 56,770 people will be diagnosed with pancreatic cancer and about 45,750 people will die of the disease. Pancreatic cancer is the fourth most common cause of cancer-related deaths in the United States and Western Europe. Unfortunately, unlike other malignancies, very little progress has been made and outcome for patients with advanced pancreatic cancer has been dismal, with a 5-year survival rate for metastatic pancreatic cancer of approximately 2%. Pancreatic cancer has surpassed breast cancer as the third leading cause of cancer death in the United States and is on track to surpass colorectal cancer, to move to the second leading cause of cancer related deaths in the United States around 2020.

BRCA1 and BRCA2 are tumor suppressor genes located on chromosome 17 and chromosome 13 respectively. They control cell growth by repairing DNA damage and thus prevent tumor development. Mutations in these genes predispose an individual to develop malignant tumors. It is well established that the presence of BRCA1 and BRCA2 mutations can significantly increase the lifetime risk for developing breast and ovarian cancer, as high as 85% and 40% respectively. BRCA1/2 mutations have been detected in 4-7% of patients with pancreatic cancer, with a 2-6 fold increase in risk, associated with these mutations. These patients tend to be younger. Among pancreatic cancer patients with Ashkenazi Jewish ancestry, the prevalence of BRCA1/2 mutations is 6-19%, with mutations more common for BRCA2. NCCN guideline recommends that germline testing should be considered for all patients with pancreatic cancer and is especially recommended for those with a personal history of cancer, family history or clinical suspicion of a family history of pancreatic cancer. Approximately 10% of pancreatic cancer cases have a familial component. When hereditary cancer syndrome is suspected in patients with pancreatic cancer, genetic counseling should be considered.

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). The BRCA gene plays an important role in DNA repair via Homologous Recombination (HR). Mutation of BRCA gene results in loss of BRCA function and likely deregulates Homologous Recombination (HR) pathway. Majority of patients with Germline BRCA mutations (gBRCA) have HR Deficiency (HRD) resulting in inability to repair double strand breaks. HRD can also occur due to other mechanisms, such as germline mutations, somatic mutations and epigenetic modifications of other genes involved in the HR pathway. Patients with HRD exhibit specific clinical behaviors, and improved responses to treatments, such as platinum-based chemotherapy and PARP Inhibitors. MOA-of-LYNPARZA

The PARP (Poly ADP Ribose Polymerase) family of enzymes include PARP1 and PARP2, which repair damaged DNA. LYNPARZA® is a first-in-class PARP enzyme inhibitor that causes cell death in tumors that already have a DNA repair defect, such as those with BRCA1 and BRCA2 mutations, through the concept of synthetic lethality. Malignancies such as epithelial ovarian cancers with Homologous Recombination Deficiency have demonstrated sensitivity to PARP inhibitors. Recent studies have confirmed that PARP inhibitors are effective not only in ovarian cancers displaying germline or somatic BRCA mutations but also in cancers with HRD caused by other underlying etiologies. LYNPARZA® in a Phase II trial, demonstrated antitumor activity in heavily pretreated metastatic pancreatic cancer patients with a germline BRCA mutation. Maintenance treatment with LYNPARZA® in BRCA mutated ovarian cancer patients resulted in significant improvement in Progression Free Survival.

The POLO (Pancreas Cancer Olaparib Ongoing) trial was conducted to evaluate the efficacy of maintenance therapy with LYNPARZA® in metastatic pancreatic adenocarcinoma patients with a germline BRCA mutation whose disease had not progressed during first-line platinum-based chemotherapy. In this international, multicenter, randomized, double-blind, placebo-controlled Phase III study, 154 patients with BRCA mutant disease were randomly assigned in a 3:2 ratio, to receive maintenance LYNPARZA® tablets 300 mg twice daily (N=92) or matching placebo (N=62). The median patient age was 57 years. Eligible patients should have received at least 16 weeks of continuous first-line platinum-based chemotherapy for metastatic pancreatic cancer and maintenance treatment was initiated 4-8 weeks after the last dose of first-line chemotherapy had been administered. Maintenance intervention was continued until disease progression. Crossover to LYNPARZA® was not permitted during this trial. The Primary end point was Progression Free Survival and Secondary end points included Objective Response Rate (ORR) and Quality of Life.

The median PFS was significantly longer in the LYNPARZA® group compared to the placebo group (7.4 months versus 3.8 months; HR for disease progression or death=0.53; P=0.004). This suggested a 47% reduction in the risk of disease progression or death. At 2 years, 22% of the patients in the LYNPARZA® group did not have disease progression compared with 9.6% of patients in the placebo group. The interim analysis of Overall Survival showed no significant difference, with a median 18.9 months for the LYNPARZA® group and 18.1 months for the placebo group (HR=0.91; P=0.68). Health-related Quality of Life scores were also not significantly different. Grade 3 or higher adverse events were 40% in the LYNPARZA® group and 23% in the placebo group and 5% and 2% of the patients, respectively, discontinued therapy because of an adverse event.

It was concluded that among metastatic pancreatic cancer patients with germline BRCA mutation and whose cancer has not progressed during platinum-based chemotherapy, Progression Free Survival was significantly longer with maintenance LYNPARZA® than with placebo. This study allows identifying patients with metastatic pancreatic cancer who will likely benefit from PARP inhibition. Maintenance Olaparib for Germline BRCA-Mutated Metastatic Pancreatic Cancer. Golan T, Hammel P, Reni M, et al. N Engl J Med 2019; 381:317-327

Antibiotic Treatment Prior to Immune Checkpoint Inhibitor Therapy has a Detrimental Effect on Response Rates and Overall Survival

RR

SUMMARY: The American Cancer Society estimates that in 2019, there will be an estimated 1,762,450 new cancer cases diagnosed and 606,880 cancer deaths in the United States. Immunotherapy with Immune Checkpoint Inhibitors (ICIs) has revolutionized cancer care and has become one of the most effective treatment options by improving Overall Response Rate and prolongation of survival across multiple tumor types. These agents target Programmed cell death protein-1 (PD-1), Programmed cell death ligand-1 (PD-L1), Cytotoxic T-Lymphocyte-Associated protein-4 (CTLA-4), and many other important regulators of the immune system.

Preclinical studies have suggested that immune-based therapies for cancer may have a very complex interplay with the host’s microbiome and there may be a relationship between gut bacteria and immune response to cancer. The crosstalk between microbiota in the gut and the immune system allows for the tolerance of commensal bacteria (normal microflora) and oral food antigens and at the same time enables the immune system to recognize and attack opportunistic bacteria. Immune Checkpoint Inhibitors strongly rely on the influence of the host’s microbiome, and the gut microbial diversity enhances mucosal immunity, dendritic cell function, and antigen presentation. Broad-spectrum antibiotics can alter the bacterial composition and bacterial diversity of our gut, by killing the good bacteria. It has been postulated that this may negate the benefits of immunotherapy and influence treatment outcomes.Unleashing-T-Cell-Function-with-Combination-Immunotherapy

The authors conducted this study to determine whether there was an association between antibiotic therapy administered prior to or concurrently with ICI therapy and Overall Survival (OS) and Response Rates, in patients with cancer, treated with ICIs in routine clinical practice. In this prospective, multicenter cohort study, 196 patients with cancer who received ICI therapy were recruited at two tertiary care centers between January 2015 and April 2018. Majority of enrolled patients had Non-Small Cell Lung Cancer (N=119), but patients with Melanoma (N=38) as well as Urologic and Head and Neck cancers (N=39) were also included in the analysis. The median age was 68 years, and majority of patients had metastatic disease at the time of treatment initiation with ICIs and 96% of patients received anti-PD-1/PD-L1 therapy alone. Broad spectrum antibiotics up to 30 days prior to commencement of ICI qualified as prior antibiotic exposure whereas concurrent treatment with antibiotics was defined as antibiotic treatment from the first day of ICI treatment until cessation. Beta-lactams were the most commonly prescribed antibiotic class, and were given as a single course for less than 7 days. When antibiotics were administered concurrently with ICIs, patients tended to be treated longer and with multiple courses. The common indication for both prior and concurrent antibiotic treatment was respiratory infections, and 15% of patients received antibiotic therapy prior to ICI therapy, whereas 35% of patients received antibiotics concurrently with ICIs. The Primary endpoint was Overall Survival (OS), calculated from the time of ICI therapy commencement and radiologic response to treatment, with disease refractory to ICI therapy defined as progressive disease 6-8 weeks after the first ICI dose, without evidence of pseudoprogression.

In this analysis, antibiotic treatment prior to ICI therapy had a significant adverse effect on Overall Survival, with a median survival of only 2 months for those who received prior antibiotic treatment versus 26 months for antibiotic-naive patients (HR=7.4; P<0.001). Further, patients who had received prior antibiotic treatment had a higher likelihood of primary refractoriness to ICIs, compared to those who did not receive antibiotics (81% versus 44% (P<0.001). The poor OS outcomes when patients received antibiotic treatment prior to ICI therapy were noted, irrespective of tumor site (OS in NSCLC 26 vs 2.5 months, P<0.001, OS in Melanoma 14 vs 3.9 months, P<0.001, OS in other tumors 11 vs 1.1 months, P <0.001). Multivariate analyses confirmed that prior antibiotic therapy and response to ICI therapy were associated with OS, independent of tumor site, disease burden, and performance status. Antibiotic treatment administered concurrently with ICIs however, was not associated with worse Overall Survival.

It was concluded that treatment with antibiotics prior to therapy with Immune Checkpoint Inhibitors in routine clinical practice, is associated with a worse treatment response and Overall Survival in unselected group of patients. This study suggests that timing of antibiotic exposure may be crucial and the authors recommend that studies are urgently required to investigate antibiotic-mediated alterations of gut microbiota as a determinant of poorer outcomes, following treatment with Immune Checkpoint Inhibitors. Association of Prior Antibiotic Treatment With Survival and Response to Immune Checkpoint Inhibitor Therapy in Patients With Cancer. Pinato DJ, Howlett S, Ottaviani D, et al. JAMA Oncol. 2019, Sep 12. doi: 10.1001/jamaoncol.2019.2785. [Epub ahead of print]

Liquid Biopsy DNA Methylation Assay Highly Specific for Cancer Detection and Prognosis

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SUMMARY: Screening both healthy and high-risk populations with a peripheral blood sample (liquid biopsy) has the potential to detect cancer at an early stage, with an increased opportunity to offer curative therapies. Screening assays for cancer should be highly specific with a low rate of false-positive results and overdiagnosis. Analysis of cell-free DNA (cfDNA) with a Liquid Biopsy is presently approved to select EGFR targeted therapies (cobas EGFR mutation test), in patients with advanced Non Small Cell Lung Cancer. However, the role of cell-free DNA analysis for early detection of cancer is not well established.

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, observational study 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 20 tumor types and all clinical stages), across 142 sites in the US and Canada. 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’s multi-cancer early detection blood test through three pre-planned sub-studies. The authors in 2018 previously reported that it is possible to detect early-stage lung cancer, with a high degree of specificity, from a simple blood test, using targeted sequencing and whole-genome sequencing. In this substudy, liquid biopsy could accurately detect over 40% of early-stage lung cancers (Stage I-IIIA), with 98% specificity. It was determined that whole-genome bisulfite sequencing for DNA methylation was the most effective approach for early cancer detection. Liquid-Biopsy

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. 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, 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.

In two separate presentations, the authors in this present sub-study reported the results for patients with more than 20 cancer subtypes across all stages and evaluated the prognostic significance of detecting abnormal patterns of cfDNA methylation by whole-genome bisulfite sequencing (WGBS) assay. The goal of targeted methylation assay was to detect both early and advanced disease cancers, and improve clinical outcomes

Liu, MC, et al. reported outcomes for 2,301 participants (1422 had cancer and 879 did not) with more than 20 cancer types (12 prespecified and high-risk cancers included Lung, HR negative Breast, Colorectal, Anorectal, Esophageal, Gastric, Liver, Pancreatic, Head and Neck, Ovary, Myeloma and Lymphoid neoplasms) across all stages. The 12 prespecified cancers account for two thirds of all cancer deaths in the US. At 99% specificity, the sensitivity for these 12 high-risk cancers ranged from 59-86% at early stages (stages I–III). For all 20 cancer types, the overall detection rate across all stages was 55%. Additionally, a Tissue of Origin result was provided for 94% of all cancers detected and of these, the assay correctly identified the Tissue of Origin in 90% of cases, which the authors commented is critical for guiding efficient downstream workup for a positive signal.

Oxnard GR, et al. performed an exploratory longitudinal analysis and reported the results of the Overall Survival of 1,320 participants with more than 20 cancer types in this substudy, thereby evaluating the prognostic significance of detection by this assay. Across all stages of disease, cancers detected by cfDNA whole-genome bisulfite sequencing for DNA methylation were associated with significantly worse survival than those not detected by the blood test. The 2-year Overall Survival was less than 50% among patients whose cancers were detected by the assay compared with 2-year OS of over 90% for those whose cancers were not detected by this assay. The poor prognostic ability of this assay was seen in both cancers that presented with symptoms and those found via screening suggesting that DNA–based detection with this methylation assay may be an indicator of prognosis. In multivariate analysis, cancers detected by this assay had double the risk of death (HR=2.6; P< 0.001) when accounting for clinical stage, cancer type, histologic grade, age, sex, and method of diagnosis and also had comparable prognostic significance to clinical stage (P <0.001).

It was concluded from these two presentations that cfDNA test based on the presence of DNA methylation is highly specific at detecting high-risk malignancies, with very high accuracy for identifying the tissue of origin, and may also have prognostic value.

Genome-wide Cell-free DNA (cfDNA) Methylation Signatures and Effect on Tissue of Origin (TOO) Performance. Liu MC, Jamshidi A, Venn O, et al. 2019 ASCO Annual Meeting. Abstract 3049. Presented June 1, 2019.

Prognostic significance of blood-based cancer detection in plasma cell-free DNA (cfDNA): Evaluating risk of overdiagnosis. Oxnard GR, Chen X, Fung ET, et al. 2019 ASCO Annual Meeting. Abstract 1545. Presented June 3, 2019.

SBRT Superior to Standard Radiotherapy in Stage I Non-Small Cell Lung Cancer

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SUMMARY: 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 2019, about 228,150 new cases of lung cancer will be diagnosed and 142,670 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. Approximately 15% of patients present with early stage (T1-2 N0) disease, and these numbers are likely to increase with the implementation of Lung Cancer screening programs. Patients with early stage disease unless medically unfit, undergo surgical resection with a curative intent. Those who are not surgical candidates are often treated with conventional Radiation Therapy, over a period of 4 to 6 weeks.

Stereotactic Body Radiation Therapy (SBRT) is a non-surgical procedure that allows delivery of significantly higher doses of precisely focused radiation to the tumor, compared to conventional Radiation Therapy, with less collateral damage to the surrounding normal tissue. The technologies used for SBRT include GAMMA KNIFE® which uses highly focused gamma rays, Proton Beam therapy which uses ionized Hydrogen or Protons, Linear Accelerator (LINAC) and CYBER KNIFE® which use Photons, to target the tumor tissue. Because SBRT is fractionated and delivered over 1-5 days, the short-and long-term side effects of radiation therapy are decreased and may allow higher total dosage to be given. Previously published single-arm trials have shown high local control with SBRT, with no significant difference in Overall Survival, compared with conventional Radiotherapy. This Phase III trial was conducted to prospectively assess the effect of SBRT on local control, Overall Survival, toxicity and Quality of Life.SBRT-Treatment

In this multicentre, randomized, Phase III trial, 101 eligible patients with biopsy proven Stage I (T1-T2aN0M0) NSCLC, diagnosed on the basis of FDG PET, who were medically inoperable or had refused surgery, were enrolled. Patients were randomly assigned in a 2:1 ratio to SBRT (54 Gy in three 18 Gy fractions, or 48 Gy in four 12 Gy fractions if the tumor was less than 2 cm from the chest wall)-(N=66) or standard Radiotherapy (66 Gy in 33 daily 2 Gy fractions or 50 Gy in 20 daily 2.5 Gy fractions (N=35), based on institutional preference. The tumor had to be non-central and peripherally located, at least 1 cm in the mediastinum and 2 cm from the bifurcation of the lobar bronchi. Patients were stratified by T stage and operability (medically operable but refused surgery versus inoperable). The Primary endpoint was time to local treatment failure and Secondary endpoints included Overall Survival, treatment related toxicity and Quality of Life. The median follow up for local treatment failure was 2.1 years for standard Radiotherapy group and 2.6 years for those patients assigned to SBRT.

Local treatment failure was noted in 14% of patients in the SBRT group whereas 31% of patients in the standard Radiotherapy group progressed locally. Freedom from local treatment failure was significantly improved the SBRT group compared with a standard radiotherapy group (HR=0.32, P=0.0077). Median time to local treatment failure was not reached in either group. Median Overall Survival was 5 years in the SBRT group and 3 years in the standard Radiotherapy group (HR=0.53; P=0.027). Overall Survival at 2 years was 77% for those receiving SBRT and 59% for those in the standard Radiotherapy group. Treatment related toxicities were low in both groups and there were no significant differences in Quality of Life between the treatment groups.

It was concluded that in patients with inoperable peripherally located Stage 1 NSCLC, compared with standard Radiotherapy, SBRT resulted in superior local control of the primary disease without an increase in major toxicity, and improvement in Overall Survival. The authors added that these findings suggest that SBRT should be the treatment of choice for this patient group. Stereotactic ablative radiotherapy versus standard radiotherapy in stage 1 non-small-cell lung cancer (TROG 09.02 CHISEL): a phase 3, open-label, randomised controlled trial. Ball D, Tao Mai G, Vinod S, et al. Lancet Oncol 2019;20:494-503

IMBRUVICA® and RITUXAN® Combination Superior to FCR in Patients with CLL

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SUMMARY: The American Cancer Society estimates that for 2019, about 20,720 new cases of Chronic Lymphocytic Leukemia (CLL) will be diagnosed in the US and 3,930 patients will die of the disease. CLL accounts for about 25% of the new cases of leukemia and the average age at the time of diagnosis is around 71 years. B-cell CLL is the most common type of leukemia in adults, accounting for about 11% of all hematologic malignancies. Chemoimmunotherapy with Fludarabine, Cyclophosphamide, and Rituximab (FCR) has long been the gold standard and the most commonly used treatment regimen for younger, fit, treatment naïve patients with CLL.This is based on phase III trial data showing improvement in both Progression Free Survival (PFS) and Overall Survival (OS) compared with chemotherapy alone. FCR regimen however is associated with significant toxicities and cannot be tolerated by all CLL patients. IMBRUVICA® (Ibrutinib) is an oral, irreversible inhibitor of BTK and inhibits cell proliferation and promotes programmed cell death (Apoptosis) by blocking B-cell activation and signaling. IMBRUVICA® in phase III trials showed improved PFS and OS when compared to Chlorambucil in previously untreated, elderly patients with CLL. Nonetheless, the efficacy of IMBRUVICA® as a first-line treatment for younger CLL patients (70 years or younger), compared to the most efficacious regimen such as FCR, is unknown.BCR-Signal-Pathways-and-MOA-of-New-Agents

E1912, led by the ECOG-ACRIN Research Group (ECOG-ACRIN), is a randomized phase III study in which IMBRUVICA® plus RITUXAN® (Rituximab) was compared to Fludarabine, Cyclophosphamide, and RITUXAN® (FCR) chemotherapy regimen, in previously untreated patients aged 70 years or younger with Chronic Lymphocytic Leukemia (CLL) or Small Lymphocytic Lymphoma (SLL). In this trial, 529 patients were randomly assigned in a 2:1 ratio to receive IMBRUVICA® 420 mg orally daily until disease progression along with RITUXAN® 50 mg/m2 on day 1 of cycle 2, 325 mg/m2 on day 2 of cycle 2, 500 mg/m2 on day 1 of cycles 3-7 (N=354) or six courses of Fludarabine 25 mg/m2 IV along with Cyclophosphamide 250 mg/m2 IV days 1-3 and RITUXAN® 50 mg/m2 IV on day 1 of cycle 1, 325 mg/m2 on day 2 of cycle 1, 500 mg/m2 on day 1 of cycles 2-6, given every 28 days (N=175). The median age was 58 years and 40% of the patients were 60 years of age or older. The Primary endpoint was Progression Free Survival (PFS) and the Secondary endpoint was Overall Survival (OS).

With a median follow up of 33.6 months, at the first interim analysis, IMBRUVICA® plus RITUXAN® significantly improved PFS and was 89.4%, compared to 72.9% with FCR, at 3 years (HR=0.35; P<0.0001). This meant a 65% reduction in the risk of progression or death with IMBRUVICA® plus RITUXAN® compared with FCR. The combination of IMBRUVICA® plus RITUXAN® also demonstrated improved OS and was 98.8% at 3 years versus 91.5% with FCR (HR=0.17; P=0.0003). This suggested that IMBRUVICA® plus RITUXAN® combination reduced the risk of death by 83% compared with FCR. In a subgroup analysis, the PFS benefit with IMBRUVICA® plus RITUXAN® was seen independent of age, sex, Performance Status (0-2), disease stage, as well as presence or absence of cytogenetic abnormality, deletion 11q23. At the time of this analysis, IMBRUVICA® plus RITUXAN® was also superior to FCR among IGHV unmutated patients (90.7% versus 62.5% at 3 years,HR=0.26; P<0.0001),suggesting a 74% reduction in the risk of progression or death with IMBRUVICA® plus RITUXAN®, compared to FCR. A statistically significant benefit however was not observed among those with IGHV mutations, although there was a positive trend noted (HR=0.44; P=0.07). Treatment-related Grade 3 or higher toxicities were similar in both treatment groups. FCR however was more frequently associated with Grade 3 or higher infectious complications than IMBRUVICA® plus RITUXAN® combination (20.3% versus 10.5%; P<0.001).

It was concluded that a combination of IMBRUVICA® and RITUXAN® was superior and significantly improved PFS and OS, when compared to FCR among patients 70 years of age or under, with previously untreated CLL. These findings may have immediate practice changing implications and establish IMBRUVICA®-based therapy as the most effective first-line therapy for untreated patients with CLL. Ibrutinib–Rituximab or Chemoimmunotherapy for Chronic Lymphocytic Leukemia. Shanafelt TD, Wang XV, Kay NE, et al. N Engl J Med 2019; 381:432-443

KISQALI® Improves Overall Survival in Advanced Breast Cancer

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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. About 268,600 new cases of female breast cancer will be diagnosed in 2019 and about 41,760 women will die of the disease. Breast cancer is the second leading cause of cancer death in the US. Approximately 70% of breast tumors express Estrogen Receptors and/or Progesterone Receptors and these patients are often treated with anti-estrogen therapy as first line treatment. The incidence of breast cancer among women under the age of 50 has been increasing by 0.2% per year. Premenopausal breast cancer may be biologically different than post menopausal breast cancer and diagnosis of breast cancer at a young age has been associated with adverse outcomes and less sensitivity to endocrine therapy. Further, premenopausal women are often excluded from hormone therapy trials. The incidence of metastatic disease at the time of diagnosis among patients with Hormone Receptor (HR)- positive breast cancer, has been increasing by about 2% per year.

Cyclin Dependent Kinases (CDK) play a very important role to facilitate orderly and controlled progression of the cell cycle. Genetic alterations in these kinases and their regulatory proteins have been implicated in various malignancies. Cyclin Dependent Kinases 4 and 6 (CDK4 and CDK6) phosphorylate RetinoBlastoma protein (RB), and initiate transition from the G1 phase to the S phase of the cell cycle. RetinoBlastoma protein has antiproliferative and tumor-suppressor activity and phosphorylation of RB protein nullifies its beneficial activities. CDK4 and CDK6 are activated in HR-positive breast cancer, promoting breast cancer cell proliferation. Further, there is evidence to suggest that endocrine resistant breast cancer cell lines depend on CDK4 for cell proliferation. The understanding of the role of Cyclin Dependent Kinases in the cell cycle, has paved the way for the development of CDK inhibitors.Cell-Cycle-Inhibition-by-RIBOCICLIB-A-CDK4-and-CDK6-Inhibitor

There are presently three CDK4/6 inhibitors approved by the FDA and they include KISQALI® (Ribociclib), IBRANCE® (Palbociclib) and VERZENIO® (Abemaciclib). All three agents have demonstrated similar, significantly prolonged Progression Free Survival (PFS) when administered in combination with endocrine therapy, as first-line treatment, in women with HR-positive metastatic breast cancer (MONALEESA-2 with KISQALI®, PALOMA-2 with IBRANCE® and MONARCH-3 with VERZENIO®). These trials for the first-line treatment of advanced breast cancer however excluded premenopausal women. The toxicities were slightly different with neutropenia more commonly encountered in the IBRANCE® and KISQALI® studies and diarrhea more often noted with VERZENIO®. KISQALI® (Ribociclib) is an orally bioavailable, selective, small-molecule inhibitor of CDK4/6 that blocks the phosphorylation of RetinoBlastoma protein, thereby preventing cell-cycle progression and inducing G1 phase arrest. It is four times more selective for CDK4 than for CDK6.

The MONALEESA-7 trial is an international, randomized, double-blind, placebo-controlled, Phase III trial in which KISQALI® in combination with endocrine therapy was compared with placebo in combination with endocrine therapy, in premenopausal or perimenopausal women with HR-positive, HER2- negative advanced breast cancer. Patients (N=672) were randomly assigned in a 1:1 ratio, to receive KISQALI® at 600 mg orally once daily for 21 days of each 28 day cycle (N=335), or matching placebo (N=337). Both groups received ZOLADEX® (Goserelin) 3.6 mg administered subcutaneously on day 1 of each 28 day cycle. Patients also received either a nonsteroidal Aromatase Inhibitor (Letrozole 2.5 mg or Anastrozole 1 mg) or Tamoxifen 20 mg, orally once daily continuously. The choice of endocrine therapy was made on the basis of the patient’s previous adjuvant or neoadjuvant therapy or investigator or patient preference. Crossover was not permitted between the two treatment groups. Patients were stratified according to the presence or absence of liver or lung metastases, previous chemotherapy for advanced disease and endocrine therapy. The Primary end point was Progression Free Survival (PFS) and Secondary endpoint included Overall Survival (OS). The superior PFS data with KISQALI® compared to endocrine therapy alone, was previously reported. The authors herein report the results on Overall Survival.

After a median follow up of 34.6 months, the addition of KISQALI® to endocrine therapy resulted in significantly longer Overall Survival, compared to endocrine therapy alone. The estimated OS at 42 months was 70.2% in the KISQALI® group and 46.0% in the placebo group (HR for death=0.71; P=0.00973), suggesting a 29% reduction in the risk of death. No new safety signals were observed and in the KISQALI® group, more instances of QT-interval prolongation were observed in patients who received Tamoxifen than in those who received an Aromatase Inhibitor, but without symptomatic arrhythmias or Torsades de pointes.

It was concluded that KISQALI® along with endocrine therapy significantly prolonged Overall Survival, compared to endocrine therapy alone, among pre and perimenopausal patients with advanced HR-positive, HER2-negative breast cancer and these findings represent a major treatment advance in this patient group. Overall Survival with Ribociclib plus Endocrine Therapy in Breast Cancer. Im S-A, Lu Y-S, Bardia A, et al. N Engl J Med 2019; 381:307-316.

MUCOSITIS

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Mucositis or inflammation of the mucous membranes is one of the most common complications of cancer treatment. This condition is often underestimated and involves the entire gastrointestinal tract. Oral mucositis can result in significant morbidity and for this reason properly managing oral mucositis can have a significant impact on the patient’s quality of life. With the breakdown in the mucosal barrier, patients with severe myelosuppression and mucositis can potentially contract serious infections, requiring hospitalization1. Further, appropriate management of oral mucositis will allow optimal treatment of the patient’s cancer without treatment interruptions.

Pathogenesis of Mucositis

It involves the production of reactive oxygen species (ROS) which damages the mucosal cells and its vasculature, followed by active inflammation, ulceration, and subsequent healing2,3. Genetics may also play a role in increasing the incidence and duration of mucositis in certain individuals4,5.

WHO (World Health Organization) Mucositis Scale

Grade 1 – Oral Soreness,Erythema

Grade 2 – Ulcers but able to eat solids

Grade 3 – Oral ulcers and able to take liquids only

Grade 4 – Oral alimentation impossible

The risk to develop mucositis can be Treatment Related or Patient Related

Risk Factors-Treatment Related

1. Multiple cycles of chemotherapy with agents such as 5-FU, Methotrexate, Cisplatin and Cyclophosphamide.

2. Concurrent chemotherapy and radiation

3. Myeloablative therapy and Transplantation

Risk Factors-Patient Related

1. Women are at a greater risk6

2. African Americans tend to have a lower incidence of mucositis with Fluorouracil than Caucasians7

3. Oral mucosa dryness

4. Irritation and trauma caused by ill fitting dentures

5. Dental hygiene

Prevention of Oral Mucositis

• Oral hygiene should be rigorously maintained by flossing every day, brushing teeth with a soft toothbrush twice a day and rinsing the mouth with bland rinses such as normal saline, baking soda or water.

• Cryotherapy (Ice chips) for 30 minutes before and for 4 to 6 hours after therapy. Cryotherapy causes vasoconstriction resulting in decreased drug delivery to the oral mucosa8.

• KEPIVANCE® (Palifermin), a keratinocyte growth factor, given IV, only for patient’s undergoing myeloablative therapy and transplantation9. This agent increases the thickness of the mucosa.

• ETHYOL® (Amifostine), an organic, thiophosphate given IV, which scavenges reactive oxygen species (ROS), thereby reducing toxicity to the normal mucosa. It is recommended for prevention of xerostomia associated with head and neck radiation, as well as mucositis associated with high-dose melphalan. It is also approved for the prevention of renal toxicity associated with platinum compounds10.

Treatment of Oral Mucositis

• Bland rinses as mentioned above

• Topical anesthetics such as lidocaine viscous or gel

• Magic mouthwash, which is a combination of viscous lidocaine, nystatin, diphenhydramine, and dyclonine magnesium hydroxide. When using topical anesthetics, patients should be instructed not to swallow or gargle, as this can impair the gag reflex and put the patient at a risk for aspiration pneumonia. No more than 25 ml of topical anesthetic is recommended over a 24 hr period, as there is a chance for systemic absorption.

• Other agents that may benefit include GELCLAIR®, MUGARD®, CAPHOSOL®, and MUCOTROL®.

• Myelosuppressed patients with severe mucositis can be at an increased risk of contracting viral and fungal infections. Prophylactic antiviral and antifungal agents must be considered along with prophylactic antibiotics and hematopoietic growth factors.

• Severe mucositis can be associated with pain. If narcotics are indicated, transdermal or liquid preparations should be considered. Managing constipation while on narcotics should not be overlooked.

• Some patients receiving radiation treatment for head and neck cancer may benefit from a prophylactic percutaneous endoscopy gastrostomy (PEG) tube.

• Patient’s with excess oral secretions secondary to mucositis may benefit from antihistamines and scopolamine patches.

• Chlorhexidine and alcohol-containing mouthwashes should be avoided.

• It is important that these patients are adequately hydrated and nourished, avoiding any food products that could traumatize the mucosa.

Reference List

1. Elting LS, Cooksley C, Chambers M, Cantor SB, Manzullo E, Rubenstein EB. The burdens of cancer therapy. Clinical and economic outcomes of chemotherapy-induced mucositis. Cancer 2003; 98(7):1531-1539.

2. Sonis ST. Pathobiology of oral mucositis: novel insights and opportunities. J Support Oncol 2007; 5(9 Suppl 4):3-11.

3. Sonis ST. The pathobiology of mucositis. Nat Rev Cancer 2004; 4(4):277-284.

4. Ulrich CM, Yasui Y, Storb R et al. Pharmacogenetics of methotrexate: toxicity among marrow transplantation patients varies with the methylenetetrahydrofolate reductase C677T polymorphism. Blood 2001; 98(1):231-234.

5. Zhang X, Diasio RB. Regulation of human dihydropyrimidine dehydrogenase: implications in the pharmacogenetics of 5-FU-based chemotherapy. Pharmacogenomics 2007; 8(3):257-265.

6. Chansky K, Benedetti J, Macdonald JS. Differences in toxicity between men and women treated with 5-fluorouracil therapy for colorectal carcinoma. Cancer 2005; 103(6):1165-1171.

7. McCollum AD, Catalano PJ, Haller DG et al. Outcomes and toxicity in african-american and caucasian patients in a randomized adjuvant chemotherapy trial for colon cancer. J Natl Cancer Inst 2002; 94(15):1160-1167.

8. Tartarone A, Matera R, Romano G, Vigliotti ML, Di RN. Prevention of high-dose melphalan-induced mucositis by cryotherapy. Leuk Lymphoma 2005; 46(4):633-634.

9. Spielberger R, Stiff P, Bensinger W et al. Palifermin for oral mucositis after intensive therapy for hematologic cancers. N Engl J Med 2004; 351(25):2590-2598.

10. Kouvaris JR, Kouloulias VE, Vlahos LJ. Amifostine: the first selective-target and broad-spectrum radioprotector. Oncologist 2007; 12(6):738-747.

US Preventive Services Task Force Recommendations on BRCA Mutation Testing

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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. About 268,600 new cases of female breast cancer will be diagnosed in 2019 and about 41,760 women will die of the disease. Breast cancer is the second leading cause of cancer death in the US. 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 percent 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 5-10% of breast cancer cases and 15% of ovarian cancer cases. The estimated prevalence of potentially harmful BRCA1/2 mutations is 6% in women with cancer onset before age 40 years, and 2.1% among Ashkenazi Jewish women. Among individuals with a family history of breast or ovarian cancer, BRCA1 mutation prevalence is approximately 13%, BRCA2 mutation prevalence is about 8%, and prevalence of either mutation is about 20%. Mutations in the BRCA1/2 genes increase breast cancer risk by 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.

The US Preventive Services Task Force (USPSTF) in this publication updated the 2013 recommendations on risk assessment, genetic counseling, and genetic testing for BRCA-related cancer. These recommendations are based on the evidence of both the benefits and harms of the service and this assessment does not consider the costs of providing a service.

The USPSTF reviewed the evidence on risk assessment, genetic counseling, and genetic testing for potentially harmful BRCA1/2 mutations in asymptomatic women who have never been diagnosed with BRCA-related cancer, as well as those with a previous diagnosis of breast, ovarian, tubal, or peritoneal cancer who have completed treatment and are considered cancer free. In addition, the USPSTF reviewed interventions to reduce the risk for breast, ovarian, tubal, or peritoneal cancer in women with potentially harmful BRCA1/2 mutations, including intensive cancer screening, medications, and risk-reducing surgery.

Recommendations

1) The USPSTF recommended that primary care clinicians assess women with a personal or family history of breast, ovarian, tubal, or peritoneal cancer or who have an ancestry associated with BRCA1/2 gene mutations, with an appropriate brief familial risk assessment tool. Women with a positive result on the risk assessment tool should receive genetic counseling and, if indicated after counseling, genetic testing.

2) The USPSTF recommends against routine risk assessment, genetic counseling, or genetic testing for women whose personal or family history or ancestry is not associated with potentially harmful BRCA1/2 gene mutations.

Risk Assessment

Clinicians should obtain medical and family history specifically inquiring patients about specific types of cancer, primary cancer sites, which family members were affected, whether relatives had multiple types of primary cancer, the age at diagnosis, age at death, and sex of affected family members, both immediate (parents and siblings) as well as more distant (aunts, uncles, grandparents, and cousins). Women who have a family or personal history of breast, ovarian, tubal, or peritoneal cancer should be evaluated by clinicians, to determine the need for in-depth genetic counseling, using appropriate familial risk assessment tools, recognized by the USPSTF. Familial risk assessment factors include breast cancer diagnosis before age 50 years, bilateral breast cancer, presence of both breast and ovarian cancer in one individual, male family members with breast cancer, multiple cases of breast cancer in the family, one or more family members with 2 primary types of BRCA-related cancer (such as ovarian cancer), and Ashkenazi Jewish ancestry. Breast cancer risk assessment models such as the National Cancer Institute Breast Cancer Risk Assessment Tool, which is based on the Gail model are not designed to identify BRCA-related cancer risk and should not be used for this purpose.

Genetic Counseling

Genetic counseling includes detailed kindred analysis and risk assessment for potentially harmful BRCA1/2mutations, identification of individuals for testing, discussion of the benefits and harms of genetic testing, interpretation of results after testing, and discussion of management options. Genetic counseling should be performed by trained health professionals, including suitably trained primary care clinicians.

Genetic Testing

Testing for BRCA1/2 mutations should be performed only when an individual with history suggesting inherited cancer susceptibility, is willing to talk with a qualified health professional, trained to provide genetic counseling and interpret test results, and when test results will aid in decision-making. BRCA mutation testing should begin with a relative with known BRCA-related cancer, including male relatives, to determine if a clinically significant mutation is detected in the family, before testing individuals without cancer. If an affected family member with a BRCA-related cancer is not available, then the relative with the highest probability of mutation should be tested. Reporting BRCA1/2 mutations identified by genetic tests should include a 5-tier terminology system, using the terms “pathogenic,” “likely pathogenic,” “uncertain significance,” “likely benign,” and “benign.

Treatment and Interventions for women with harmful BRCA1/2 mutations

The USPSTF recommends that clinicians offer intensive screening and risk-reducing medications such as Tamoxifen, Raloxifene, or Aromatase Inhibitors to women at increased risk for breast cancer and at low risk for adverse medication effects. General care for these individuals may include risk-reducing mastectomy and salpingo-oophorectomy.

US Preventive Services Task Force. Risk Assessment, Genetic Counseling, and Genetic Testing for BRCA-Related Cancer: US Preventive Services Task Force Recommendation Statement. JAMA. 2019;322:652-665.

FDA Approves INREBIC® for Myelofibrosis

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SUMMARY: The FDA on August 16, 2019, approved INREBIC® (Fedratinib) for adults with Intermediate-2 or High-risk Primary or Secondary (post-Polycythemia Vera or post-Essential Thrombocythemia) Myelofibrosis (MF).

Myelofibrosis is a MyeloProliferative Neoplasm (MPN) characterized by ineffective hematopoiesis, progressive fibrosis of the bone marrow and potential for leukemic transformation. This stem cell disorder is Philadelphia Chromosome negative and manifestations include anemia, splenomegaly and related symptoms such as abdominal distension and discomfort with early satiety. Cytokine driven debilitating symptoms such as fatigue, fever, night sweats, weight loss, pruritus and bone or muscle pain can further impact an individual’s quality of life. Myelofibrosis can be Primary (PMF) or Secondary to Polycythemia Vera (PV) or Essential Thrombocythemia (ET).JAK-STAT-Signaling-Pathway The JAK-STAT signaling pathway has been implicated in the pathogenesis of Myelofibrosis. This pathway normally is responsible for passing information from outside the cell through the cell membrane to the DNA in the nucleus, for gene transcription. Janus Kinase (JAK) family of tyrosine kinases are cytoplasmic proteins and include JAK1, JAK2, JAK3 and TYK2. JAK1 helps propagate the signaling of inflammatory cytokines whereas JAK2 is essential for growth and differentiation of hematopoietic stem cells. These tyrosine kinases mediate cell signaling by recruiting STAT’s (Signal Transducer and Activator of Transcription), with resulting modulation of gene expression. In patients with MPN, the aberrant myeloproliferation is the result of dysregulated JAK2-STAT signaling as well as excess production of inflammatory cytokines associated with this abnormal signaling. These cytokines contribute to the symptoms often reported by patients with MF. JAK2 mutations such as JAK2 V617F are seen in approximately 60% of the patients with PMF and ET and 95% of patients with PV. Unlike CML where the BCR-ABL fusion gene triggers the disease, JAK2 mutations are not initiators of the disease and are not specific for MPN. Further, several other genetic events may contribute to the abnormal JAK2-STAT signaling. Currently, JAKAFI® (Ruxolitinib) is the only drug that has been approved by the FDA for Myelofibrosis.

INREBIC® is a highly selective JAK2 inhibitor and is active against a broader family of kinases and kinase mutants. This is unlike JAKAFI® which is a JAK1/2 inhibitor. The approval of INREBIC®was based on findings from the Phase III JAKARTA-2 study, which evaluated INREBIC® in patients with Primary or Secondary Myelofibrosis. In this double-blind, randomized, placebo-controlled trial, 289 patients with Intermediate-2 or High-risk MF, post-Polycythemia Vera MF, or post-Essential Thrombocythemia MF with splenomegaly, were randomized to receive either INREBIC® 500 mg (N=97), 400 mg (N=96) or placebo (N=96), once daily for at least 6 consecutive 4-week cycles. The Primary endpoint was the proportion of patients achieving 35% or more reduction in spleen volume from baseline at the end of cycle 6 measured by MRI or CT, with a follow up scan 4 weeks later. Secondary end point was symptom response (50% or more reduction in total symptom score, assessed using the modified Myelofibrosis Symptom Assessment Form).

The Primary end point was achieved by 37% of the patients receiving INREBIC® at the 400 mg dose compared with 1% of patients who were in the placebo group (P <0.0001). The median duration of spleen response was 18.2 months for the INREBIC® 400 mg group. Further, 40% of patients who received INREBIC® at the 400 mg dose, experienced a 50% or more reduction in Myelofibrosis-related symptoms, whereas only 9% of patients receiving placebo experienced a decrease in these symptoms (P<0.0001). The most common adverse reactions seen in 20% or more patients who received INREBIC® were diarrhea, nausea, anemia, and vomiting.

In conclusion, INREBIC® therapy significantly reduced splenomegaly and symptom burden in patients with Myelofibrosis. This FDA approval represents an important milestone for patients with Myelofibrosis and clinicians now have a new treatment option for these patients, including those previously treated with JAKAFI®. https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-fedratinib-myelofibrosis

Dramatic Increase in ColoRectal Cancer Incidence among Young Adults

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Even though the incidence of Colorectal cancer (CRC) in the United States has been rapidly declining overall, primarily driven by screening, the incidence however has been increasing among adults younger than 50 years of age, according to data in the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) program. Based on these findings, the American Cancer Society in 2018 updated its guidelines to include a “qualified recommendation” to begin CRC screening at the age of 45 yrs. 

In a recently published retrospective study, the proportion of the total number of patients diagnosed with CRC under the age of 50 yrs rose from 10% in 2004 to 12.2% in 2015 (P<0.0001). Younger adults presented with more advanced stage of disease (Stage III/IV) than those 50 yrs or older (51.6% versus 40.0% respectively). When racial and ethnic groups were stratified by sex, among men with a diagnosis of CRC before age 50, non‐Hispanic whites showed a proportional increase in diagnosis (P<0.0001), whereas among women, both Hispanic whites (P<0.05) and non‐Hispanic whites (P<0.001) had increases in the proportion of CRC diagnosed before age 50. The rates of CRC diagnosis in young adults increased over time, regardless of income level (P<0.001).The highest proportion of young adult CRC diagnoses occurred in the highest income group. The proportion of CRC cases diagnosed in younger individuals rose in urban areas (P<0.001), but not in rural areas. Health Care Providers should be mindful of these data, when screening guidelines are discussed with patients.