VISTOGARD® – An Antidote for 5-FU Overexposure

SUMMARY: VISTOGARD® (Uridine Triacetate) is presently approved in the US for the emergency treatment of adult and pediatric patients, who had severe or life-threatening toxicities within 4 days of treatment, following an overdose of 5-FluoroUracil (5-FU) or XELODA® (Capecitabine). Toxicities related to 5-FU or XELODA® can be caused by impaired drug clearance, Dihydropyrimidine Dehydrogenase deficiency, and other genetic variations in the enzymes that metabolize 5-FU. Additionally, 5-FU overdoses resulting in death can occur because of infusion pump errors, dosage miscalculations and accidental or suicidal ingestion of XELODA®. These toxicities can manifest as severe mucositis, cytopenias, central neurotoxicity and acute cardiomyopathy.

VISTOGARD® is a pyrimidine analog and following oral administration is deacetylated by nonspecific esterases, yielding Uridine in the circulation. Uridine is a direct antagonist of 5-FU and competitively inhibits 5-FU from incorporating in normal tissues, thus reducing cell damage and cell death. The authors reported the efficacy of VISTOGARD® in two open-label clinical trials in which patients who presented with a 5-FU/XELODA® overdose (N=142) or patients with early onset of severe toxicities (N=26), were treated. These patients received VISTOGARD® granules 10 grams every 6 hours for 20 doses, starting within 96 hours after the termination of 5-FU/XELODA® therapy. The median age was 58 years. Because there were no antidotes available for 5-FU toxicity at the time of this study, and the use of a placebo was unethical, the outcomes of this study were compared to a historical cohort of patients gathered from all available literature (control group), who overdosed on 5-FU and received only best supportive care. The primary endpoint of these studies was survival at 30 days or until chemotherapy could resume, if prior to 30 days.

Of the 142 overdose patients treated with VISTOGARD®,137 patients (96%) survived and had a rapid reversal of severe acute cardiotoxicity and neurotoxicity and additionally, mucositis and leukopenia were prevented, or the patients recovered from them. In the historical control cohort, 21 of 25 patients (84%) died. Among the 141 VISTOGARD® treated overdose patients with a diagnosis of cancer, 53 resumed chemotherapy in less than 30 days (median time after 5-FU of 19.6 days), indicating a rapid recovery from toxicity. The most common toxicities in patients receiving VISTOGARD® included, nausea, vomiting and diarrhea.

The authors concluded that VISTOGARD® is a safe and effective antidote for 5-FU overexposure, and can facilitate rapid recovery and resumption of chemotherapy. Patients should take VISTOGARD® as soon as possible after overdose, regardless of symptoms or within 4 days of severe or life threatening toxicity. It should be noted that VISTOGARD® is not recommended for treatment of non-emergency adverse events associated with 5-FU and XELODA®, as this therapy may significantly decrease the efficacy of these chemotherapy agents. Emergency use of uridine triacetate for the prevention and treatment of life-threatening 5-fluorouracil and capecitabine toxicity. Ma WW, Saif WM, El-Rayes BF, et al. Cancer 2017;123:345-356.

Late Breaking Abstract – ASCO 2016 ROVA-T, First Targeted Treatment for Small Cell lung Cancer

SUMMARY: Lung cancer is the second most common cancer in both men and women and the American Cancer Society estimates that for 2016, about 224,390 new cases of lung cancer will be diagnosed and over 158,000 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Small cell lung cancer (SCLC) accounts for approximately 13-15 percent of all lung cancers and is aggressive. The five year survival rate for extensive stage SCLC is less than 5% with a median survival of 9 to 10 months from the time of diagnosis. Patients are often treated with chemotherapy and radiation in the first and second line setting. The Overall Response Rate (ORR) in the third line setting is approximately 18% and the one year Overall Survival is approximately 12%. These patients typically have a poor prognosis with limited treatment options. Delta-like protein 3 also known as DLL3, is encoded by the DLL3 gene and is expressed on the surface of tumor cells but not in normal adult tissues. Patients with high-grade pulmonary NeuroEndocrine Tumors, Small Cell Lung Cancer (SCLC) and Large Cell NeuroEndocrine Carcinoma (LCNEC) have increased expression of DLL3 protein (increased expression seen in approximately 80% of the tumors).

Rovalpituzumab Tesirine (Rova-T) is a first-in-class DLL3-targeted Antibody-Drug Conjugate (ADC) comprised of a humanized anti-DLL3 monoclonal antibody, conjugated to a DNA-damaging PyrroloBenzoDiazepine (PBD) dimer toxin. Rova-T delivers the cytotoxin directly to the DLL3-expressing cancer cells while minimizing toxicity to healthy cells.

The authors in this open-label, Phase 1a/1b, multicenter study, included seventy four (N=74) patients with SCLC who had progressed after at least one previous systemic therapy. Previous therapies included Platinum/Etoposide (96%) and radiation therapy (82%). The majority of patients (76%) had extensive disease at presentation, with 28% having CNS metastases. Over 85% of patients had DLL3 expression on 1% or more of tumor cells and 67% of the patients had DLL3 expression on 50% or more of tumor cells (DLL3-high expression). Patients received Rova-T at doses ranging from 0.05 to 0.8 mg/kg every 3 or 6 weeks. The median age was 61 years. The primary endpoints of the study were Overall Response Rate (ORR) and Maximum Tolerated Dose and secondary endpoints included Overall Survival (OS) and Progression Free Survival (PFS).

Rova-T demonstrated an Overall Response Rate of 39% and Clinical Benefit Rate (stable disease or better) of 89%, in patients with recurrent or refractory Small Cell Lung Cancer identified with high expression of DLL3. The one year Overall Survival rate was 32% in the patient group identified with high expression of DLL3. The most common adverse events were rash, fatigue, nausea, decreased appetite, pleural effusion, peripheral edema and thrombocytopenia.

The authors concluded that Rovalpituzumab Tesirine (Rova-T) has significant single-agent anti-tumor activity with manageable toxicity, in recurrent or refractory SCLC, and is the first biomarker-directed therapy to be defined, for the treatment of Small Cell Lung Cancer. Safety and efficacy of single-agent rovalpituzumab tesirine (SC16LD6.5), a delta-like protein 3 (DLL3)-targeted antibody-drug conjugate (ADC) in recurrent or refractory small cell lung cancer (SCLC). Rudin CM, Pietanza MC, Bauer TM, et al. J Clin Oncol 34, 2016 (suppl; abstr LBA8505)

ASCO Guideline – Adjuvant Systemic Therapy Decision Making for Early Stage Operable Breast Cancer

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 life time. Approximately, 246,660 new cases of invasive breast cancer will be diagnosed in 2016 and 40,450 women will die of the disease. Patients with early stage breast cancer often receive adjuvant therapy. The ASCO Clinical Practice Guidelines Committee endorsed a set of Cancer Care Ontario guideline recommendations that addressed the role of a range of patient and disease characteristics, in selecting adjuvant therapy for women with early-stage breast cancer. This guideline does not address the selection of optimal adjuvant chemotherapy regimens.

Guideline Question: Which patient and disease factors should be considered in selecting adjuvant therapy for women with early-stage breast cancer?

Target Population: Female patients who are being considered for, or who are receiving systemic therapy for early-stage invasive breast cancer (Stages I–IIA, T1N0–1, T2N0).

RECOMMENDATIONS

Decisions regarding adjuvant therapy should be based on relevant (either prognostic or predictive) information and consideration given to-

1) Lymph node status, T stage, Estrogen Receptor status, Progesterone Receptor status, HER2 status, tumor grade, and presence of tumor lymphovascular invasion.

2) Risk-stratification tools including Oncotype DX score (for hormone receptor-positive, N0 or N1mic or isolated tumor cell, and HER2-negative cancers) and Adjuvant! Online.

3) Patient age, menopausal status, and medical comorbidities.

For patients in whom chemotherapy would likely be tolerated and for whom chemotherapy is acceptable, adjuvant chemotherapy should be considered if the following characteristics are present:

1) Lymph node-positive tumor (at least one node with macrometastatic deposit > 2 mm)

2) Estrogen receptor-negative tumor (> 5 mm)

3) HER2-positive tumor

4) High-risk node-negative tumors (> 5 mm) and another high-risk feature

5) Adjuvant! Online 10-year risk of death from breast cancer > 10%.

Patients with node-negative early stage breast cancer with high risk features who should be considered candidates for chemotherapy include

1) Tumors > 5 mm

2) Grade III histology

3) Triple negative tumors

4) Lymphovascular invasion

5) Oncotype DX recurrence score associated with an estimated distant relapse risk ≥ 15% at 10 years

6) HER2-positive tumors

(The ASCO panel suggested an estimated distant relapse risk > 20% in this setting).

Patients with tumor size < 5 mm, node-negative tumors, and no other high-risk features, may not benefit from adjuvant chemotherapy.

Adjuvant chemotherapy may not be required in patients with HER2-negative, strongly ER-positive, and PR-positive breast cancer and any of the following additional characteristics: positive nodes with micrometastasis only (< 2 mm), or Tumor size < 5 mm, or Oncotype DX recurrence score with an estimated distant relapse risk < 15% at 10 years. (The ASCO panel suggested an estimated distant relapse risk < 10% at 10 years in this setting)

ASCO Panel Discussion Points

Areas that warrant further consideration include-

1) Tumor histology and adjuvant therapy recommendations

2) Risk-stratification tools and proposed Oncotype DX recurrence score thresholds to guide decisions about chemotherapy

3) Patient factors in decision-making.

The panel noted that some uncommon breast cancer subtypes (eg, tubular, mucinous) may have a favorable prognosis and that such histologic information may be relevant for making decisions regarding adjuvant chemotherapy. Additionally, factors such as Grade III disease and lymphovascular invasion generally should not be used in isolation in decision-making but considered within the overall clinical context.

Role of patient and disease factors in adjuvant systemic therapy decision making for early-stage, operable breast cancer: Henry NL, Somerfield MR, Abramson VG, et al. American Society of Clinical Oncology endorsement of Cancer Care Ontario guideline recommendations. J Clin Oncol 34:2303-2311, 2016

Influence of Tumor Genetics (MSI) on Prognostic Effect of BRAF and KRAS Mutations in Patients with Colon Cancer

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 135,000 new cases of ColoRectal Cancer will be diagnosed in the United States in 2016 and over 49,000 patients are expected to die of the disease. The role of adjuvant chemotherapy in patients with Stage III ColoRectalCancer (CRC) has been well established, with improvement in Disease Free Survival (DFS) and Overall Survival (OS). However, not all patients equally benefit from this therapy. Patients with MSI (Micro Satellite Instability) tumor phenotype have better survival when cancer is at an earlier stage although this beneficial effect in Stage III colon cancer remains unclear.

The DNA MisMatchRepair (MMR) system is responsible for molecular surveillance and works as an editing tool that identifies errors within the microsatellite regions of DNA and removes them. Defective MMR system leads to MSI (Micro Satellite Instability) and hypermutation, triggering an enhanced antitumor immune response. MSI (Micro Satellite Instability) is therefore a hallmark of defective/deficient DNA MisMatchRepair (MMR) system and occurs in 15% of all colorectal cancers. Defective MisMatchRepair can be a sporadic or heritable event. Approximately 65% of the MSI tumors are sporadic and when sporadic, the DNA MisMatchRepair gene is MLH1. Defective MisMatchRepair can also manifest as a germline mutation occurring in 1 of the 4 MisMatchRepair genes which include MLH1, MSH2, MSH6, PMS2. This produces Lynch Syndrome (Hereditary Nonpolyposis Colorectal Carcinoma – HNPCC), an autosomal dominant disorder and is the most common form of hereditary colon cancer, accounting for 35% of the MSI colorectal cancers. MSI tumors tend to have better outcomes and this has been attributed to the abundance of tumor infiltrating lymphocytes in these tumors from increase immunogenicity. These tumors are susceptible to PD-1 blockade and respond to treatment with checkpoint inhibitors such as Pembrolizumab (N Engl J Med 372:2509-2520, 2015).

MSI (Micro Satellite Instability) testing is performed using a PCR based assay and MSI-High refers to instability at 2 or more of the 5 mononucleotide repeat markers and MSI-Low refers to instability at 1 of the 5 markers. Patients are considered Micro Satellite Stable (MSS) if no instability occurs. MSI-L and MSS are grouped together because MSI-L tumors are uncommon and behave similar to MSS tumors. Tumors considered MSI-H have deficiency of one or more of the DNA MisMatchRepair genes. MMR gene deficiency can be detected by ImmunoHistoChemistry (IHC). MLH1 gene is often lost in association with PMS2.

Patients with stage IV colorectal cancer are now routinely analyzed for extended RAS and BRAF mutations because KRAS mutations are predictive of resistance to EGFR targeted therapy and BRAF V600E is recognized as a marker of poor prognosis in this patient group. BRAF mutations occur in approximately 45% of patients with sporadic colorectal cancer with MSI but not seen in patients with Lynch syndrome. The prognostic effect of these mutations in early stage disease has however remained controversial. This publication is a Post Hoc Analysis of the PETACC-8 study, a randomized phase III trial, in which patients with resected Stage III colon cancer received treatment with adjuvant FOLFOX with or without Cetuximab. The authors in this publication examined the prognostic effect of BRAF and KRAS mutations in this patient population, as it relates to MSI of the tumor.

The PETACC-8 trial enrolled 2559 patients with surgically resected colon cancer, treated with adjuvant FOLFOX chemotherapy regimen. The median age was 60 years. MisMatch Repair, BRAF V600E, and KRAS exon 2 mutational status, were determined on tumor blocks that were collected prospectively from the enrolled patients. MSI phenotype was noted in 9.9% (N=177), KRAS mutations in 33.1% (N=588) and BRAF V600E mutations in 9% (N=148) of the patients. The primary end point was Disease Free Survival (DFS) and Overall Survival (OS), as it relates to these mutations.

In multivariate analysis, MSI and BRAF V600E mutations for DFS were not prognostic, whereas KRAS mutation was associated with significantly shorter DFS (P<0.001) and OS (P=0.008). The subgroup analysis showed that in patients with Micro Satellite Stable (MSS) tumors, DFS and OS was inferior among those with KRAS and BRAF V600E mutation and were independently associated with worse clinical outcomes. In patients with MSI tumors, KRAS status was not prognostic, whereas BRAF V600E mutation was associated with significantly longer DFS (P=0.04), but not OS (P=0.08).

The authors based on this large analysis of patients with Stage III colon cancer receiving FOFOX adjuvant chemotherapy, concluded that BRAF V600E and KRAS mutations were significantly associated with shorter DFS and OS in patients with Micro Satellite Stable (MSS) tumors, but not in patients with MSI tumors. Prognostic Effect of BRAF and KRAS Mutations in Patients With Stage III Colon Cancer Treated With Leucovorin, Fluorouracil, and Oxaliplatin With or Without Cetuximab. A Post Hoc Analysis of the PETACC-8 Trial. Taieb J, Zaanan A, Le Malicot, et al. JAMA Oncol. 2016;2:643-653.

Late Breaking Abstract – ASH 2016 Dramatic Responses in Patients with Refractory Diffuse Large B-Cell Lymphoma (DLBCL) with anti-CD19 CAR T Cells

SUMMARY: The American Cancer Society estimates that in 2016, about 72,580 people will be diagnosed with Non Hodgkin Lymphoma (NHL) in the United States and about 20,150 individuals will die of this disease. Patients with refractory DLBCL have poor outcomes with chemotherapy, and have a response rate of 20%-30% and median overall survival of approximately 6 months (J Clin Oncol 34, 2016, suppl; abstr. 7516), and thus represents a significant unmet medical need. Chimeric Antigen Receptor (CAR) T-cell therapy is a type of immunotherapy in which T cells are collected from the patient’s own blood and are genetically engineered to produce special receptors on their surface called Chimeric Antigen Receptors (CAR’s). The cytotoxic T cells with these chimeric antigen receptors on their surface are now able to recognize a specific antigen on tumor cells. These engineered CAR T-cells which are grown in the lab are then infused into the patient and they in turn proliferate in the patient’s body and the engineered receptor on their surface help recognize and kill cancer cells that expresses that specific antigen. CD19 antigen is expressed by majority of the B cell malignancies and therefore most studies using CAR T-cell therapy have focused on the treatment of advanced B-cell malignancies such as Chronic Lymphocytic Leukemia (CLL), Acute Lymphoblastic Leukemia (ALL) and Non Hodgkin lymphoma (NHL), such as Diffuse Large B-Cell Lymphoma (DLBCL).

The KTE-C19 (anti-CD19 Chimeric Antigen Receptor (CAR) T cells) construct consists of an extracellular domain which recognizes and targets the CD19 antigen on the surface of tumor cells, and the intracellular domains to avoid activation of hidden signals to the T-cells. ZUMA-1 is a multicenter phase I/II trial of anti-CD19 Chimeric Antigen Receptor (CAR) T cells (KTE-C19) in refractory, aggressive NHL and this study included patients with Diffuse Large B-Cell Lymphoma (DLBCL), Primary Mediastinal B-Cell Lymphoma (PMBCL), and Transformed Follicular Lymphoma (TFL). In the phase I component of this study, 43% of the patients had ongoing Complete Responses at 12 months.

Phase II of ZUMA-1 included 2 patient cohorts based on the tumor type. Cohort 1 included DLBCL and patients in cohort 2 had PMBCL or TFL. Refractory disease was defined as progressive or stable disease as best response to last line of therapy, or disease progression 12 months or less after Autologous Stem Cell Transplant (ASCT). All included patients received a prior anti-CD20 antibody and an Anthracycline-containing regimen. The median age was 58 years, 78% were refractory to 2 or more lines of therapy, 20% relapsed less than 12 months after ASCT. Patients received a low-dose conditioning regimen of Cyclophosphamide 500 mg/m2 IV and Fludarabine 30 mg/m2 IV, daily for 3 days followed by a target dose of 2 × 106 anti-CD19 CAR T cells/kg. The primary endpoint was Objective Response Rate (ORR) and secondary endpoints include Duration of Response, frequency of adverse events (AEs), and levels of CAR T cells and serum cytokines. The authors presented the results of a pre-specified interim analysis from cohort 1 and 51 patients in cohort 1 were eligible for analysis.

The study met its primary endpoint and with a minimal follow up of three months, the ORR was 76% compared with ORR of 20% in historical controls (P<0.0001). Complete Responses were noted in 47% of the patients and Partial Response rate was 29%. Majority of the responses (92%) occurred within the first month, and the Complete Response Rate at 3 months was 33% and 39% of the patients had ongoing responses at 3 months. The treatment benefit was consistent across all subgroups of patients. The most frequent more than grade 3 toxicities were cytopenias, encephalopathy and hypophosphatemia. Grade 3 or more Cytokine Release Syndrome (CRS) and neurologic events occurred in 20-30% of the patients.

The authors concluded that this is the first reported multicenter trial of CAR T cell therapy in patients with refractory aggressive NHL and therapy with KTE-C19 induced a nearly six fold higher Complete Response Rate compared to historical outcomes and efficacy was strongly associated with peak CAR T levels. KTE-C19 (anti-CD19 CAR T Cells) Induces Complete Remissions in Patients with Refractory Diffuse Large B-Cell Lymphoma (DLBCL): Results from the Pivotal Phase 2 ZUMA-1.Neelapu SS, Locke FL, Bartlett NL, et al. Presented at: American Society of Hematology 58th Annual Meeting; December 3-6, 2016; San Diego, CA. Abstract LBA6.

FDA Approves AVASTIN® for Platinum-Sensitive Ovarian Cancer

SUMMARY: The FDA on December 7, 2016 approved AVASTIN® (Bevacizumab), either in combination with Carboplatin and Paclitaxel or in combination with Carboplatin and Gemcitabine chemotherapy, followed by AVASTIN® alone, for the treatment of patients with platinum-sensitive recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer. Platinum-sensitive disease is defined as relapse occurring six months or longer following the last treatment with a platinum-based chemotherapy. The American Cancer Society estimates that over 22,280 women will be diagnosed with ovarian cancer in the United States for 2016 and over 14,240 will die of the disease. Ovarian cancer ranks fifth in cancer deaths among women, accounting for more deaths than any other cancer of the female reproductive system. The FDA had approved AVASTIN® in combination with Paclitaxel, Pegylated Liposomal Doxorubicin, or Topotecan in 2014, for the treatment of patients with Platinum-resistant, recurrent epithelial Ovarian, Fallopian tube, or Primary Peritoneal cancer.

The present approval was based on results from two randomized, controlled Phase III studies, GOG-0213 and OCEANS trial. GOG-0213 is phase III study and was conducted by the Gynecologic Oncology Group (GOG) that enrolled 673 women with platinum-sensitive recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer. This study enrolled 673 patients with predominantly serous adenocarcinoma histology. The patients were randomly assigned to receive combination chemotherapy with Paclitaxel and Carboplatin (N=336) or the same chemotherapy along with Avastin 15 mg/kg IV every 3 weeks (N=337), followed by AVASTIN® maintenance. The median age was 60 years. The Primary endpoint of this study was Overall Survival (OS) and Secondary endpoints included Progression Free Survival (PFS) and Objective Response Rate (ORR).

There was a 5 month improvement in the median Overall Survival with the addition of AVASTIN® to chemotherapy compared with chemotherapy alone (42.6 months vs 37.3 months, respectively; HR=0.84). There was a 3.4 improvement in the median PFS in the AVASTIN® group compared to chemotherapy alone (13.8 months vs 10.4 months, respectively; HR=0.61). The Objective Response Rate (ORR) was 78% with the addition of AVASTIN® to chemotherapy versus 56% with chemotherapy alone.

OCEANS trial is a placebo-controlled, randomized, multicentre Phase III study that evaluated the safety and efficacy of AVASTIN® in combination with Carboplatin and Gemcitabine chemotherapy. This study included 484 patients with platinum-sensitive recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer who were randomly assigned to receive combination chemotherapy with Carboplatin and Gemcitabine along with placebo (N=242) or combination chemotherapy along with Avastin (N=242). The Primary endpoint of the study was Progression Free Survival and Secondary endpoints included Objective Response Rate, Overall Survival and safety.

The addition of AVASTIN® to chemotherapy significantly improved PFS compared to chemotherapy alone (12.4 months vs. 8.4 months; HR=0.46, P<0.0001). The ORR was 78% in the AVASTIN® group compared with 57% in the chemotherapy alone group.

These studies supports the use of AVASTIN® either in combination with Carboplatin and Paclitaxel or in combination with Carboplatin and Gemcitabine chemotherapy, followed by AVASTIN® alone, for patients with platinum-sensitive recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer. A phase III randomized controlled clinical trial of carboplatin and paclitaxel alone or in combination with bevacizumab followed by bevacizumab and secondary cytoreductive surgery in platinum-sensitive, recurrent ovarian, peritoneal primary and fallopian tube cancer (Gynecologic Oncology Group 0213). Coleman RL , Bradya MF, Herzog TJ, et al. Scientific Plenary (Late-Breaking Abstract). SGO 2015. Abstract 3. Presented March 28, 2015

Axillary Lymph Node Dissection Can Be Avoided in Some High Risk Breast Cancer Patients

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 246,660 new cases of invasive breast cancer will be diagnosed in 2016 and 40,450 women will die of the disease. Axillary lymph node evaluation is an important part of breast cancer staging and the presence of axillary lymph metastases decreases the 5-year survival rate by 28-40%. Axillary lymph node status remains the most powerful predictor of breast cancer recurrence and survival. Axillary Lymph Node Dissection (ALND) was first advocated in the 18th century as part of the treatment of invasive breast cancer and has been standard practice until 2 decades back. ALND can be associated with significant morbidities such as upper limb lymphedema, pain, and sensitivity disorders and this can have a major psychological impact on breast cancer patients. Sentinel Lymph Node Biopsy (SLNB) which was introduced into clinical practice in the mid 1990’s, however has now become a standard method of treatment for stage I and II breast cancer. This therapeutic surgical modality facilitates selective histopathological evaluation of the sentinel lymph nodes rather than routine lymphadenectomy, thereby sparing the patient from the morbidities associated with ALND. Several studies have shown no statistically significant difference in the axillary recurrence risk and survival rates, between these two therapeutic surgical modalities.

Neoadjuvant chemotherapy is considered standard practice in women with locally advanced breast cancer. This intervention increases the possibility of breast conserving surgery in women with locally advanced breast cancer and for tumors more than 3 cm in diameter, with good cosmetic outcomes. Close to half of the patients treated with neoadjuvant chemotherapy have no axillary lymph node involvement at the time of surgery. GANEA 2 trial was conducted to assess the feasibility and safety of SLNB, a less invasive procedure, for patients treated with neoadjuvant chemotherapy.

The researchers enrolled 590 patients with large, operable breast tumors who had no cancer in the lymph nodes as determined by axillary sonography with fine needle cytology. All patients received neoadjuvant chemotherapy, and then underwent surgery and Sentinel Lymph Node Biopsy. Cancer cells were detected in the Sentinel Lymph Node Biopsy specimens of 139 patients and these patients underwent Axillary Lymph Node Dissection.

No cancer cells were detected in the Sentinel Lymph Node Biopsy samples from 432 patients. Follow-up data was available for 416 of these patients. The median follow-up was 35.8 months. The Disease Free Survival at 3 years in the patient group who had no cancer cells in the Sentinel Lymph Node Biopsy sample, and therefore did not receive Axillary Lymph Node Dissection, was 94.8%. The Overall Survival rate was 98.7%.

The authors concluded that Axillary Lymph Node Dissection could be avoided in patients who have no signs of cancer involvement in the axillary lymph nodes, based on sonographic axillary assessment, prior to neoadjuvant chemotherapy and Sentinel Lymph Node Biopsy findings after neoadjuvant chemotherapy. In this study, the Disease Free Survival and Overall Survival rates for the patients who underwent only a Sentinel Lymph Node Biopsy after neoadjuvant chemotherapy, were comparable with the historical survival rates for patients in this situation who had Axillary Lymph Node Dissection rather than Sentinel Lymph Node Biopsy. Classe JM, Loaec C, Alran S, et al. Sentinel node detection after neoadjuvant chemotherapy in patient without previous axillary node involvement (GANEA 2 trial): follow-up of a prospective multi-institutional cohort. Presented at: 2016 San Antonio Breast Cancer Symposium; December 6-10, 2016; San Antonio, TX. Abstract S2-07.

FDA Approves TECENTRIQ® for Non-Small Cell Lung Cancer

SUMMARY: The FDA on October 18, 2016, approved TECENTRIQ® (Atezolizumab) for the treatment of patients with metastatic non-small cell lung cancer (NSCLC) whose disease progressed during or following platinum-containing chemotherapy. Lung cancer is the second most common cancer in both men and women and accounts for about 13% of all new cancers and 27% of all cancer deaths. The American Cancer Society estimates that for 2016 about 224,390 new cases of lung cancer will be diagnosed and over 158,000 patients will die of the disease. Non Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers. The treatment paradigm for malignancies has been rapidly evolving, with a better understanding of the Immune checkpoints or gate keepers. Immune checkpoints are cell surface inhibitory proteins/receptors that are expressed on activated T cells. They harness the immune system and prevent uncontrolled immune reactions. Survival of cancer cells in the human body may be to a significant extent related to their ability to escape immune surveillance, by inhibiting T lymphocyte activation. The T cells of the immune system therefore play a very important role in modulating the immune system. Under normal circumstances, Immune checkpoints or gate keepers inhibit an intense immune response by switching off the T cells of the immune system. With the recognition of Immune checkpoint proteins and their role in suppressing antitumor immunity, antibodies are now available that target the membrane bound inhibitory Immune checkpoint proteins/receptors such as CTLA-4 (Cytotoxic T-Lymphocyte Antigen 4, also known as CD152), PD-1(Programmed cell Death 1), as well as Programmed cell Death Ligands (PD-L1), that are expressed by cells in the tumor micro environment. By targeting the Immune check point proteins or their ligands, T cells are unleashed, resulting in T cell proliferation, activation and a therapeutic response.

TECENTRIQ® (Atezolizumab) is an anti PD-L1 monoclonal antibody designed to directly bind to PD-L1 expressed on tumor cells and tumor-infiltrating Immune Cells, thereby blocking its interactions with PD-1 and B7.1 receptors and thus enabling the activation of T cells and restoring tumor-specific T-cell immunity. The approval of TECENTRIQ® was based two international, clinical trials (OAK and POPLAR trials). TECENTRIQ® demonstrated survival benefit compared to Docetaxel in a multicenter, randomized, phase II study (POPLAR trial). In this study, the median Overall Survival was 12.6 months and 9.7 months (HR=0.69) for the TECENTRIQ® and Docetaxel groups respectively.

OAK trial is a global, multicentre, open-label, randomized, controlled Phase III study in which 1225 patients with locally advanced or metastatic NSCLC, whose disease had progressed following previous treatment with platinum-containing chemotherapy, were enrolled. Patients with both squamous and non-squamous histology were randomized in a 1:1 ratio to receive either TECENTRIQ® 1200 mg IV every 3 weeks or Docetaxel 75 mg/m2 IV every 3 weeks. Patients were stratified according to PD-L1 status, number of prior chemotherapy regimens and histology. The median age was 64 years, 25% had 2 prior lines of therapy and 26% had squamous histology. The co-primary endpoints were Overall Survival (OS) in all randomized patients and in a PD-L1 selected subgroup in the primary analysis population. Secondary endpoints included Progression Free Survival, Objective Response Rate, Duration of Response and Safety.

The primary efficacy analysis was conducted and reported in the first 850 of 1225 total enrolled patients. The median Overall Survival was 13.8 months in the TECENTRIQ® group compared to 9.6 months in the Docetaxel group (HR=0.74; P=0.0004), with a 26% improvement in Overall Survival in the patient group who received TECENTRIQ®. This benefit was seen regardless of their PD-L1 expression levels, including patients whose tumors displayed PD-L1 expression of less than 1%. Patients with high PD-L1 expression had more pronounced benefit with TECENTRIQ® with a 59% improvement in OS compared with Docetaxel (HR=0.41; P<0.0001). The OS benefit was similar in patients with squamous or non-squamous histology. The most common adverse reactions in patients in patients treated with TECENTRIQ® were fatigue, decreased appetite, dyspnea, cough, nausea, musculoskeletal pain, and constipation.

The authors concluded that TECENTRIQ® offers a new second-line therapeutic strategy for patients with Non Small Cell Lung Cancer, with Overall Survival benefit, regardless of the PD-L1 status of the tumor. Primary analysis from OAK, a randomized phase III study comparing atezolizumab with docetaxel in 2L/3L NSCLC. Barlesi F, Park K, Ciardiello F et al. Abstract LBA44_PR. Presented at: 2016 ESMO Congress; October 7–11 (2016) Copenhagen, Denmark.

Late Breaking Abstract – ASH 2016 Superior Efficacy Data with Pacritinib in Myelofibrosis

SUMMARY: 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). 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.

Pacritinib is a potent JAK2 inhibitor, without significant JAK1 inhibition. It additionally targets FLT3, IRAK1, and CSF1R. Preliminary studies have shown minimal myelosuppression with Pacritinib. JAKAFI® (Ruxolitinib) is a potent JAK1 and JAK2 inhibitor approved by the FDA in 2011 to treat intermediate or high-risk Myelofibrosis. It is however not indicated for patients with platelet counts under 50,000/μl, and this group represents approximately one third of Myelofibrosis patients and have limited or no treatment options. Previously published PERSIST-1 trial showed that Pacritinib significantly reduced Spleen Volume and Myelofibrosis associated symptoms, in patients with low platelet count, when compared to Best Available Therapy (excluding JAKAFI®).

PERSIST-2 is an open label, phase III study in which the safety and efficacy of Pacritinib was compared with currently available therapies, including JAKAFI®, thus expanding the definition of Best Available Therapy (BAT). A total of 311 patients with platelet counts 100,000/μl or less were randomly assigned in a 1:1:1 ratio to receive Pacritinib 200 mg BID (N=107), 400 mg QD (N=104) or Best Available Therapy (N=100). The efficacy population in the Intent To Treat group included a total of 221 patients. Approximately half of the study population had platelet counts of less than 50,000/μl. Over 40% of the patients in both the treatment groups had prior therapy with JAKAFI®. About 60-70% of the patients had a diagnoses of Primary Myelofibrosis, and half of the patients fell in the International Prognostic Scoring System (IPSS) Intermediate-2 risk category. The two coprimary endpoints were the proportion of patients achieving 35% or greater reduction in Spleen Volume (SVR) as measured by MRI or CT scan and the proportion achieving a 50% or more improvement in symptoms such as fatigue, bone pain, itching, and abdominal pain after 24 weeks of follow up. The secondary objectives were to compare Pacritinib BID and Pacritinib QD, individually to BAT.

It was noted that 18% of patients who received Pacritinib achieved a 35% or greater reduction in Spleen Volume from baseline to week 24, compared to 3% of those in the BAT group (P=0.001). In the patient group who received Pacritinib twice daily, 32% reported a 50% or more reduction in symptoms compared with 14% in the BAT group (P=0.01). Further, patients treated with Pacritinib required fewer red blood cell transfusions and additionally, patients who received Pacritinib twice daily had substantially greater improvement in platelet count among those who had platelets counts 50,000/μl or less at enrollment. The most common adverse events related to Pacritinib included nausea, vomiting, diarrhea, anemia, and low platelets.

The authors concluded that this is the only randomized trial to date in patients with Myelofibrosis and thrombocytopenia that enrolled patients who had prior therapy with a JAK2 inhibitor. Regardless, Pacritinib was more effective at Spleen Volume Reduction than BAT and Pacritinib given BID was even more effective than QD dosing. Results of the Persist-2 Phase 3 Study of Pacritinib (PAC) Versus Best Available Therapy (BAT), Including Ruxolitinib (RUX), in Patients (pts) with Myelofibrosis (MF) and Platelet Counts <100,000/µl. Hoffman R, Talpaz M, Gerds AT, et al. 58th ASH Annual Meeting and Exposition; San Diego, California; December 2-6, 2016. Abstract LBA-5.

Late Breaking Abstract – ESMO 2016 FASLODEX® Superior to ARIMIDEX® as Initial Therapy in Advanced Breast Cancer

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 246,660 new cases of invasive breast cancer will be diagnosed in 2016 and 40,450 women will die of the disease. Estrogen Receptor (ER) positive breast cancer cells are driven by estrogens. Approximately 60-65% of breast tumors express Estrogen Receptors and/or Progesterone Receptors and this is a predictor of response to endocrine therapy. These patients are often treated with anti-estrogen therapy as first line treatment. In premenopausal woman, the ovary is the main source of estrogen production, whereas in postmenopausal women, the primary source of estrogen is the Aromatase enzyme mediated conversion of androstenedione and testosterone to estrone and estradiol, in extragonadal/peripheral tissues. NOLVADEX® (Tamoxifen) is a nonsteroidal Selective Estrogen Receptor Modulator (SERM) and works mainly by binding to the Estrogen Receptor and thus blocks the proliferative actions of estrogen on the mammary tissue. ARIMIDEX® (Anastrozole), FEMARA® (Letrozole) and AROMASIN® (Exemestane) are Aromatase Inhibitors (AIs) that binds to the Aromatase enzyme and inhibit the conversion of androgens to estrogens in the extra-gonadal tissues. FASLODEX® (Fulvestrant) is an estrogen antagonist and like NOLVADEX®, binds to estrogen receptors (ERs) competitively, but unlike NOLVADEX® causes rapid degradation and loss of ER protein (ER downregulator), and is devoid of ER agonist activity.

The superiority of ARIMIDEX® over NOLVADEX® was first established in the year 2000 following the publication of the results of a North American Multicenter Randomized Trial. In this study, ARIMIDEX® as first-line treatment in postmenopausal women with advanced breast cancer resulted in a significant increase in Time To Progression and a lower incidence of thromboembolic events and vaginal bleeding, compared to NOLVADEX®. In a previously reported phase II study (FIRST trial), first-line treatment with FASLODEX® significantly improved Time To disease Progression and Overall Survival compared with ARIMIDEX®, in patients with hormone receptor (HR) positive advanced breast cancer.

The FALCON trial is a phase III study conducted to confirm findings from the FIRST trial. This study included 462 postmenopausal women, with locally advanced or metastatic hormone receptor positive, HER2-negative, endocrine-therapy naive breast cancer. Patients were randomized to receive FASLODEX® IM at 500 mg on days 0, 1, and 28 and then every 28 days (N=230) or ARIMIDEX® 1 mg PO daily (N=232). Treatment was continued until disease progression or unacceptable toxicity. The primary endpoint was Progression Free Survival (PFS), and secondary endpoints included Overall Survival, Objective Response Rate, Clinical Benefit Rate, Duration of Response, health-related Quality of Life, and safety.

It was noted that FASLODEX® provided better disease control with a median PFS of 16.6 months compared to 13.8 months with ARIMIDEX® (P=0.048). Subgroup analysis showed that FASLODEX® was markedly superior to ARIMIDEX® in patients with non-visceral disease with a median Progression Free Survival of 22.3 months compared with 13.8 months for ARIMIDEX®. There was no significant improvement in the Overall Response Rate between the treatment groups. However, the median Duration of Response was 20.0 months with FASLODEX® compared to 13.2 months with ARIMIDEX®. Expected Duration of response and expected Duration of Clinical Benefit were in favor of FASLODEX® (11.4 vs 7.5 months; P=0.001) and (21.9 vs 17.5 months; P=0.001), respectively. There was no difference in Overall Survival at the time of this analysis. Rates of adverse events were similar in both treatment groups.

The authors concluded that FASLODEX® was superior to ARIMIDEX® as initial treatment of hormone receptor positive, endocrine therapy naive, advanced breast cancer. Patients with non-visceral and low volume disease, as well as elderly patients, may benefit the most with FASLODEX®, as this therapy is well tolerated with a low toxicity profile. FALCON: a phase III randomised trial of fulvestrant 500 mg vs. anastrozole for hormone receptor-positive advanced breast cancer. Ellis MJ, Bondarenko I, Trishkina E, et al. Presented at: 2016 ESMO Congress; October 7-11, 2016; Copenhagen, Denmark. Abstract LBA14.